Human organ evolution (Introduction)
by David Turell 
, Friday, April 20, 2018, 15:16 (2407 days ago)
Deep divers have big spleens:
https://www.the-scientist.com/?articles.view/articleNo/52347/title/Free-Divers-From-Sou...
Researchers have identified a genetic variant that likely results in larger spleens among the Bajau people in Southeast Asia, conferring better endurance for free diving in the ocean. The study, published today (April 19) in Cell, is an uncommon example of natural selection in modern humans that likely occurred on the order of hundreds or thousands of years.
“'This is a fascinating example of how humans can, in a relatively short amount of time, adapt to a local environment,” says study coauthor Rasmus Nielsen of the University of California, Berkeley.
"The Bajau people live in villages scattered throughout Southeast Asia, spending much of their day using traditional spears and other simple equipment to collect fish and shellfish by free diving—holding their breath. They have subsisted on this hunting method for more than 1,000 years.
"The human body has a few tricks to increase the time spent underwater in an oxygen-deficient environment. One way is to boost red blood cell production, which allows for more efficient oxygen delivery to organs and tissues, or to expand their lung capacity. A third adaptation—which the authors describe for the first time today—is increasing the size of the spleen, which stores oxygenated red blood cells and contracts during diving to release the blood cells into circulation. (another article says it boosts oxygenated red cells by 9%)
***
"Ilardo and her colleagues found that the spleens of the Bajau people were about 50 percent larger compared to the Saluans, even while taking into account individuals’ gender, age, weight, and height.
"Next, the team compared the genomic sequences of Bajau and Saluan participants to those of the Han Chinese as a control, unrelated group. Scanning for variants, the group identified the top 25 polymorphisms that were unique to the Bajau genomes, suggesting natural selection pressures were at work. The study authors created a phylogenetic tree, calculating that the Bajau and Saluans diverged about 15,000 years ago, suggesting that the Bajau-unique genetic variants evolved some time after this divergence.
***
“'This work provides the first evidence for genetic adaptation in diving human populations and elucidates genetic pathways important in hypoxia tolerance,” Tatum Simonson, who studies the physiology and genetics of high-altitude adaptation at the University of California, San Diego Health Sciences, and was not involved in the work, writes in an email to The Scientist.
"The team’s top hit, a variant adjacent to the BDKRB2 gene, is the only other gene that has previously been found to be associated with a human diving response, but not with spleen size. “We have no idea what it does to change the diving reflex. That is something we would like to explore next,” says Nielsen."
Comment: This is an organ adaptation, not a change in the human species.
Human organ evolution
DAVID: Deep divers have big spleens:
https://www.the-scientist.com/?articles.view/articleNo/52347/title/Free-Divers-From-Sou...
DAVID’s comment: This is an organ adaptation, not a change in the human species.
Yes indeed, but it confirms a pattern which runs through so many of these threads. Adaptation to the environment causes changes to the body, but we don’t know the extent to which the body can change itself. The divers didn’t tell their spleens to get bigger. Of course it may be that natural selection caused bigger spleens to outlive smaller spleens, but an alternative would be the process already observed elsewhere, i.e. that concentrated usage results in expansion of the organs used. With musicians and taxi drivers it’s parts of the brain, and with the divers it’s the spleen. One can envisage the same process occurring when land animals entered the water, and limbs became fins, or vice versa, with fish evolving legs out of fins. Not proven, of course, but there is a satisfying consistency in this hypothesis, and it still allows for your God as the inventor of the mechanism that makes it all possible.
Human organ evolution
by David Turell , Saturday, April 21, 2018, 15:19 (2406 days ago) @ dhw
DAVID: Deep divers have big spleens:
https://www.the-scientist.com/?articles.view/articleNo/52347/title/Free-Divers-From-Sou...DAVID’s comment: This is an organ adaptation, not a change in the human species.
dhw: Yes indeed, but it confirms a pattern which runs through so many of these threads. Adaptation to the environment causes changes to the body, but we don’t know the extent to which the body can change itself. The divers didn’t tell their spleens to get bigger. Of course it may be that natural selection caused bigger spleens to outlive smaller spleens, but an alternative would be the process already observed elsewhere, i.e. that concentrated usage results in expansion of the organs used. With musicians and taxi drivers it’s parts of the brain, and with the divers it’s the spleen. One can envisage the same process occurring when land animals entered the water, and limbs became fins, or vice versa, with fish evolving legs out of fins. Not proven, of course, but there is a satisfying consistency in this hypothesis, and it still allows for your God as the inventor of the mechanism that makes it all possible.
It is possible that the explanation lies with the first that dived. Those with larger spleens were more productive and produced more divers. The process repeated over and over made the folks we have today. Pure Darwin which makes sense in this case. I see no parallel in those mammals that took to water. That has to be saltation.
Human organ evolution
DAVID: Deep divers have big spleens:
https://www.the-scientist.com/?articles.view/articleNo/52347/title/Free-Divers-From-Sou...
DAVID’s comment: This is an organ adaptation, not a change in the human species.
dhw: Yes indeed, but it confirms a pattern which runs through so many of these threads. Adaptation to the environment causes changes to the body, but we don’t know the extent to which the body can change itself. The divers didn’t tell their spleens to get bigger. Of course it may be that natural selection caused bigger spleens to outlive smaller spleens, but an alternative would be the process already observed elsewhere, i.e. that concentrated usage results in expansion of the organs used. With musicians and taxi drivers it’s parts of the brain, and with the divers it’s the spleen. One can envisage the same process occurring when land animals entered the water, and limbs became fins, or vice versa, with fish evolving legs out of fins. Not proven, of course, but there is a satisfying consistency in this hypothesis, and it still allows for your God as the inventor of the mechanism that makes it all possible.
DAVID: It is possible that the explanation lies with the first that dived. Those with larger spleens were more productive and produced more divers. The process repeated over and over made the folks we have today. Pure Darwin which makes sense in this case.
Yes, as I said above (now bolded), that is natural selection. Nice to see you defending Darwin for a change! But the alternative origin seems equally possible to me: that usage resulted in expansion, which was passed on to following generations.
DAVID: I see no parallel in those mammals that took to water. That has to be saltation.
If particular usage can change the structure of the brain, and exercise can expand muscles, I don’t see why it can’t change other structures too, but the question is always to what extent, and in this case how quickly. The answer is that we don’t know. Given the choice between your God changing pre-whales’ legs into fins before they entered the water, and pre-whales entering the water with legs, and legs then changing into fins, I would opt for the latter, saltation or not. But of course that is a subjective view.
Human organ evolution
by David Turell , Sunday, April 22, 2018, 15:20 (2405 days ago) @ dhw
DAVID: Deep divers have big spleens:
https://www.the-scientist.com/?articles.view/articleNo/52347/title/Free-Divers-From-Sou...DAVID’s comment: This is an organ adaptation, not a change in the human species.
dhw: Yes indeed, but it confirms a pattern which runs through so many of these threads. Adaptation to the environment causes changes to the body, but we don’t know the extent to which the body can change itself. The divers didn’t tell their spleens to get bigger. Of course it may be that natural selection caused bigger spleens to outlive smaller spleens, but an alternative would be the process already observed elsewhere, i.e. that concentrated usage results in expansion of the organs used. With musicians and taxi drivers it’s parts of the brain, and with the divers it’s the spleen. One can envisage the same process occurring when land animals entered the water, and limbs became fins, or vice versa, with fish evolving legs out of fins. Not proven, of course, but there is a satisfying consistency in this hypothesis, and it still allows for your God as the inventor of the mechanism that makes it all possible.
DAVID: It is possible that the explanation lies with the first that dived. Those with larger spleens were more productive and produced more divers. The process repeated over and over made the folks we have today. Pure Darwin which makes sense in this case.
dhw: Yes, as I said above (now bolded), that is natural selection. Nice to see you defending Darwin for a change! But the alternative origin seems equally possible to me: that usage resulted in expansion, which was passed on to following generations.
Yes, possible.
DAVID: I see no parallel in those mammals that took to water. That has to be saltation.dhw: If particular usage can change the structure of the brain, and exercise can expand muscles, I don’t see why it can’t change other structures too, but the question is always to what extent, and in this case how quickly. The answer is that we don’t know. Given the choice between your God changing pre-whales’ legs into fins before they entered the water, and pre-whales entering the water with legs, and legs then changing into fins, I would opt for the latter, saltation or not. But of course that is a subjective view.
Enlargement of muscles is a process unique to muscles. Brain plasticity is unique to the brain. Water habitat requires enormous anatomical and physiological changes well beyond the muscle or brain changes.
Human evolution; influence of our biome
by David Turell , Saturday, June 23, 2018, 19:48 (2343 days ago) @ David Turell
Resident good bacteria have influenced our evolution:
https://www.sciencedaily.com/releases/2018/06/180621172437.htm
"Research tells us that the commensal or "good" bacteria that inhabit our intestines help to regulate our metabolism.
"In the intestine, digestive cells use an innate immune pathway to respond to harmful bacteria. But other intestinal cells, enteroendocrine cells, use the same pathway, known as IMD, to respond to "good" bacteria -- by fine-tuning body metabolism to diet and intestinal conditions.
"'Some innate immune pathways aren't just for innate immunity," says Watnick. "Innate immune pathways are also listening to the 'good' bacteria -- and responding metabolically."
"Watnick and her colleagues knew from their previous research that bacteria living in flies' intestines make a short-chain fatty acid, acetate, that is essential for the flies' own lipid metabolism and insulin signaling. Flies with no bacteria in their intestines (and hence, no acetate) accumulated fat droplets in their digestive cells. The lab of Norbert Perrimon, PhD, at Harvard Medical School had previously found similar fat droplets in flies whose enteroendocrine cells lacked tachykinin, an insulin-like protein important in growth, lipid metabolism and insulin signaling.
"'When there's a problem processing glucose or lipids, fats get stuck in these droplets in cells that are not designed for fat storage," she says.
***
"Watnick believes these fat droplets, whether caused by loss of intestinal bacteria, loss of tachykinin or loss of the innate immune pathway, are the equivalent of fatty liver. Their accumulation is a sign that the body cannot properly metabolize carbohydrates and fats. In essence, Watnick thinks these flies have metabolic syndrome, commonly associated with obesity and type 1 diabetes.
"How are intestinal bacteria, the innate immune system and metabolism related? Through a series of experiments, the team began to tease out exactly how bacteria exert their metabolic influence. They showed that:
"The innate immune pathway spurs enteroendocrine cells to produce tachykinin.
"In the absence of either bacteria or their breakdown product, acetate, no tachykinin is made.
When germ-free flies are given acetate, the innate immune pathway is reactivated and their metabolism normalizes.
"A specific innate immune receptor on enteroendocrine cells, PGRP-LC, is required to receive the acetate signal.
"'We know bacteria control our metabolism, but no one realized that bacteria were interacting with innate immune signaling pathways in enteroendocrine cells," says Watnick. "Maybe these pathways are really a system that allows cells to recognize bacteria for different reasons."
***
"Though Watnick would now like to confirm these findings in a mammalian model, the study further sketches out what appears to be a two-pronged interaction between our microbiome and our metabolism. Good bacteria ferment nutrients in our diet and release short-chain fatty acids like acetate, which help us optimize our use and storage of nutrients. Pathogenic "bad" bacteria do the opposite: They consume fatty acids, impeding healthful metabolism. An imbalance in our intestinal microbiome has been linked to obesity and sometimes contributes to malnutrition."
Comment: since is seen in fruit flies, it more than likely the bacterial mechanism was present in early primate ancestors and passed on to us. Both viruses and bacteria guided evolution.
Human evolution; our complex speech mechanism, 1
by David Turell , Tuesday, July 03, 2018, 23:41 (2333 days ago) @ David Turell
Until it is understood how complex is our ability to speak, how the changes from the ape form are so different and require obviously a tremendous number of mutations, it becomes obvious we are highly different from apes, and much more than primates. We are a giant highly different step beyond. Please read the article for completeness provided by the diagrams and for the voluminous text which has new research beyond the book I've quoted from 1992:
https://www.the-scientist.com/features/why-human-speech-is-special--64351?utm_campaign=...
"as most speech scientists agree, there is no such thing as pure phonemes (though some linguists still cling to the idea). Discrete phonemes do not exist as such in the speech signal, and instead are always blended together in words. Even “stop consonants,” such as , [p], [t], and [g], don’t exist as isolated entities; it is impossible to utter a stop consonant without also producing a vowel before or after it. As such, the consonant [t] in the spoken word tea, for example, sounds quite different from that in the word to. To produce the vowel sound in to, the speakers’ lips are protruded and narrowed, while they are retracted and open for the vowel sound in tea, yielding different acoustic representations of the initial consonant.
***
"computer systems that recognize and synthesize human speech are commonplace. All of these programs, such as the digital assistant Siri on iPhones, work at the word level. What linguists now know about how the brain functions to recover words from streams of speech now supports this word-level approach to speech reproduction. How humans process speech has also been molded by the physiology of speech production. Research on the neural bases of other aspects of motor control, such as learned hand-arm movements, suggests that phonemes reflect instruction sets for commands in the motor cortex that ultimately control the muscles that move our tongues, lips, jaws, and larynxes as we talk. But that remains a hypothesis. What is clear about language, however, is that humans are unique among extant species in the animal kingdom. From the anatomy of our vocal tracts to the complexity of our brains to the multifarious cultures that depend on the sharing of detailed information, humans have evolved the ability to communicate like no other species on Earth.
***
" In the human body, the lungs serve as the bellows, providing the source of acoustic energy for speech production. The supra-laryngeal vocal tract (SVT), the airway above the larynx, acts as the pipes, determining the formant frequencies that are produced.
***
"During speech, however, the diaphragm is immobilized and alveolar air pressure is maintained at an almost uniform level until the end of expiration, as a speaker adjusts her intercostal and abdominal muscles to “hold back” against the force generated by the elastic recoil of the lungs.
"This pressure, in combination with the tension of the muscles that make up the vocal cords of the larynx, determines the rate at which the vocal cords open and close—what’s known as the fundamental frequency of phonation (F0), perceived as the pitch of a speaker’s voice.
***
Adult women produced formant frequencies that were higher for the same vowels because their SVTs were shorter than the men’s. Adolescents’ formant frequencies were higher still. Nonetheless, human listeners are typically able to identify these spoken vowel sounds thanks to a cognitive process known as perceptual normalization, by which we unconsciously estimate the length of a speaker’s SVT and correct for the corresponding shift in formant frequencies.
***
"In short, people unconsciously take account of the fact that formant frequency patterns, which play a major role in specifying words, depend on the length of a speaker’s vocal tract. And both the fossil record and the ontogenetic development of children suggest that the anatomy of our heads, necks, and tongues have been molded by evolution to produce the sounds that clearly communicate the intended information.
***
"In addition to the anatomy of the SVT, humans have evolved increased synaptic connectivity and malleability in certain neural circuits in the brain important for producing and understanding speech. Specifically, circuits linking cortical regions and the subcortical basal ganglia appear critical to support human language."
Comment: Go to 2
Human evolution; our complex speech mechanism, 2
by David Turell , Tuesday, July 03, 2018, 23:51 (2333 days ago) @ David Turell
The Evolution of this system is complex:
"In On the Origin of Species, Darwin noted “the strange fact that every particle of food and drink which we swallow has to pass over the orifice of the trachea, with some risk of falling into the lungs.” Because of this odd anatomy, which differs from that of all other mammals, choking on food remains the fourth leading cause of accidental death in the United States. This species-specific problem is a consequence of the mutations that crafted the human face, pharynx, and tongue so as to make it easier to speak and to correctly interpret the acoustic speech signals that we hear.
"At birth, the human tongue is flat in the mouth, as is the case for other mammals. The larynx, which rests atop the trachea, is anchored to the root of the tongue. As infants suckle, they raise the larynx to form a sealed passage from the nose to the lungs, allowing them to breathe while liquid flows around the larynx. Most mammalian species retain this morphology throughout life, which explains why cats or dogs can lap up water while breathing. In humans, however, a developmental process that spans the first 8 to 10 years of life forms the adult version of the SVT. First, the skull is reshaped, shortening the relative length of the oral cavity. The tongue begins to descend down into the pharynx, while the neck increases in length and becomes rounded in the back. Following these changes, half the tongue is positioned horizontally in the oral cavity (and thus called the SVTh), while the other half (SVTv) is positioned vertically in the pharynx. The two halves meet at an approximate right angle at the back of the throat. The tongue’s extrinsic muscles, anchored in various bones of the head, can move the tongue to create an abrupt 10-fold change in the SVT’s cross-sectional area. (See illustration)
***
" This gives the adult human supralaryngeal vocal tract (SVT) two parts of nearly equal lengths that meet at a right angle: the horizontal portion of the oral cavity and the vertical portion associated with the pharynx. At the intersection of these two segments occur abrupt changes in the cross-sectional area of the SVT that allow humans to produce a range of sounds not possible for infants and nonhuman animals.
"As it turns out, the configuration of the adult human tongue’s oral and pharyngeal proportions and shape allow mature human vocal tracts to produce the vowels , , and [a] (as in the word ma). These quantal vowels produce frequency peaks analogous to saturated colors, are more distinct than other vowels, and are resistant to small errors in tongue placement.5 Thus, while not required for language, these vowel sounds buffer speech against misinterpretation. This may explain why all human languages use these vowels.
"This anatomy also begins to answer long-standing questions in language research: How did human speech come to be, and why don’t other animals talk? In 1969, my colleagues and I used a computer modeling technique to calculate the formant frequency patterns of the vowels that a rhesus macaque’s SVT could produce, based on an estimated range of tongue shapes and positions. We found that even when the monkeys’ tongues were positioned as far as possible toward the SVT configurations used by adult human speakers to yield the vowels , , and [a], the animals could not produce the appropriate formant frequencies. Three years later, using X-ray videos showing the movement of the vocal tract during newborn baby cries, we refined and replicated this study and found that, although chimpanzees and human newborns (which start life with a monkey-like SVT) produce a range of vowels, they could not produce s or s. This finding has since been replicated in independent studies, including in 2017 by the University of Vienna’s Tecumseh Fitch and colleagues. Those scientists used current computer techniques that readily model every vocal tract shape that a macaque could produce, and the research team confirmed that monkey vocal tracts were incapable of producing these vowels.
***
"It is now apparent that a massive epigenetic restructuring of the genes that determine the anatomy of the head, neck, tongue, larynx, and mouth enhanced our ability to talk after anatomically modern humans split from Neanderthals and Denisovans more than 450,000 years ago. A few years ago, David Gokhman, then at Hebrew University of Jerusalem, and colleagues reconstructed the methylated genomic regions of a 40,000-year-old Neanderthal fossil, an older Denisovan fossil, four ancient humans who lived 7,000 to 40,000 years ago, and six chimpanzees, comparing these with a methylation map of human bone cells assembled from more than 55 present-day humans. This comparison enabled the team to identify differentially methylated regions (DMRs) between the human and Neanderthal-Denisovan groups, and between humans and chimps.9,10 The researchers found that the genes that were most affected were those that controlled development of the larynx and pharynx, suggesting that epigenetic regulatory changes allowed the human vocal tract to morph into a shape that is optimal for speech.
"Of course, the fact that monkeys don’t talk like humans isn’t purely due to the physical limitations of their vocal tracts. They also lack the neural networks necessary for producing and processing speech. "
Comment: See 3 which covers mutations and neural change.
Human evolution; our complex speech mechanism, 3
by David Turell , Wednesday, July 04, 2018, 00:04 (2333 days ago) @ David Turell
Mutation changes:
"One key contributor to the evolution of human speech is the FOXP2 transcription factor. Humans, Neanderthals, and Denisovans share a mutation in the gene for FOXP2 that nonhuman primates lack. Early evidence of FOXP2’s role in human speech and language comes from studies of the KE family, a large extended family living in London in the second half of the 20th century. Some members had only one copy of FOXP2 and had extreme difficulty talking; their speech was unintelligible, and problems extended to orofacial motor control. They also had difficulties forming and understanding English sentences.
"The importance of FOXP2 has been further confirmed by knock-in mouse studies. When the human version of the gene for the FOXP2 transcription factor is inserted into mouse embryos, the animals exhibited enhanced synaptic connectivity and malleability in cortical–basal ganglia neural circuits that regulate motor control, including speech. The evolution of these circuits appears to have a deep evolutionary history going back to the Permian age, 300 million years ago. Avian versions of the FOXP1 and FOXP2 transcription factors act on the basal ganglia circuits involved when songbirds learn and execute songs.
"Exactly how the brain dictates the movement of the vocal tract to produce speech remains murky. Many studies have shown that “matrisomes” of neurons in the motor cortex are instruction sets for the motor commands that orchestrate a learned act. Assemblies of neurons in the motor cortex are formed when a task is learned, and these assemblies guide coordinated muscle activity. To sip a cup of coffee or type at a keyboard, for example, hand, arm, wrist, and other movements are coded in matrisomes. Similar matrisomes likely govern the muscles that move the tongue, lips, jaw, and larynx and control lung pressure during speech, but researchers are just starting to explore this idea. In short, brains and anatomy were both involved in the evolution of human speech and language.
"In 1971, Yale’s Edmund Crelin and I published our computer modeling study of a reconstructed Neanderthal vocal tract.14 We concluded that Neanderthals had vocal tracts that were similar to those of newborn human infants and monkeys and hence could not produce the quantal vowels [a], , and . However, the available archaeological evidence suggested that their brains were quite advanced, and that, unlike monkeys, they could talk, albeit with reduced intelligibility. We concluded that Neanderthals possessed both speech and language. In short, current research suggests a deep evolutionary origin for human language and speech, with our ancestors possessing capabilities close to our own as long as 300,000 years ago.
"Speech is an essential part of human culture, and thus of human evolution. In the first edition of On the Origin of Species, Darwin stressed the interplay of natural selection and ecosystems: human culture acts as an agent to create new ecosystems, which, in turn, directs the course of natural selection. Language is the mechanism by which the aggregated knowledge of human cultures is transmitted, and until very recent times, speech was the sole medium of language. Humans have retained a strange vocal tract that enhances the robustness of speech. We could say that we are because we can talk. "
Comment: Different folks do very different things with their languages which shows how flexible the speech mechanism can be: Hawaiian has almost no consonants, just 'l' and 'k'. In the Kalahari of Africa the bushmen use a click language. About 7,000 languages are recognized! The last paragraph indicates that we are much more than primates from a functional standpoint. We may look like apes, but the relationship stops there. Please read the whole article for deeper appreciation of my point: we are tremendously different in kind.
Human evolution; our complex speech mechanism, 3
DAVID: Until it is understood how complex is our ability to speak, how the changes from the ape form are so different and require obviously a tremendous number of mutations, it becomes obvious we are highly different from apes, and much more than primates. We are a giant highly different step beyond.
I greatly appreciate the research you do and the vast variety of articles you provide to give me and others an ongoing education, but you really don’t have to go to all these lengths to demonstrate that we are “highly different from apes” and are a “giant highly different step beyond”. It is blindingly obvious from everything that we have created (and destroyed). Thank you for all the information, but there is nothing in these posts for us to discuss.
Human evolution; our complex speech mechanism, 3
by David Turell , Wednesday, July 04, 2018, 17:33 (2332 days ago) @ dhw
DAVID: Until it is understood how complex is our ability to speak, how the changes from the ape form are so different and require obviously a tremendous number of mutations, it becomes obvious we are highly different from apes, and much more than primates. We are a giant highly different step beyond.
dhw: I greatly appreciate the research you do and the vast variety of articles you provide to give me and others an ongoing education, but you really don’t have to go to all these lengths to demonstrate that we are “highly different from apes” and are a “giant highly different step beyond”. It is blindingly obvious from everything that we have created (and destroyed). Thank you for all the information, but there is nothing in these posts for us to discuss.
I agree. I present these posts as evidence to be considered in the discussions about the presence of God and His role in evolution in line with the purposes of this website.
Human evolution; from several starting points in Africa
by David Turell , Saturday, July 14, 2018, 01:09 (2322 days ago) @ David Turell
A new theory proposes H. sapiens sprung up in several places in Africa and gradually coalesced into our current form:
https://www.theguardian.com/science/2018/jul/11/no-single-birthplace-of-mankind-say-sci...
" a team of prominent scientists is now calling for a rewriting of this traditional narrative, based on a comprehensive survey of fossil, archaeological and genetic evidence. Instead, the international team argue, the distinctive features that make us human emerged mosaic-like across different populations spanning the entire African continent. Only after tens or hundreds of thousands of years of interbreeding and cultural exchange between these semi-isolated groups, did the fully fledged modern human come into being.
***
"This continental-wide view would help reconcile contradictory interpretations of early Homo sapiens fossils varying greatly in shape, scattered from South Africa (Florisbad) to Ethiopia (Omo Kibish) to Morocco (Jebel Irhoud).
***
"The latest analysis suggests that this patchwork emergence of human traits can be explained by the existence of multiple populations that were periodically separated for millennia by rivers, deserts, forests and mountains before coming into contact again due to shifts in the climate. “These barriers created migration and contact opportunities for groups that may previously have been separated, and later fluctuation might have meant populations that mixed for a short while became isolated again,” said Scerri.
"The trend towards more sophisticated stone tools, jewellery and cooking implements also supports the theory, according to the paper...
***
“'Someone finds a skull somewhere and that’s the source of humanity. Someone finds some tools somewhere, that’s the source of humanity,” she said, describing the latest approach as: “‘Let’s be inclusive and construct a model based on all the data we have available.”
"The analysis also paints a picture of humans as a far more diverse collection of species and sub-populations than exists today. Between 200,000 and 400,000 years ago, our own ancestors lived alongside a primitive human species called Homo naledi, found in southern Africa, a larger brained species called Homo heidelbergensis in central Africa and perhaps myriad other humans yet to be discovered."
Comment: It is a strange thought to imagine various types of humans evolving everywhere from their ape-like ancestors, all to end up as one surviving type. Sounds like a purposeful drive. A major problem is the paucity of wide-spread homo fossils to fill in the story.
Human evolution; from several starting points in Africa
by Balance_Maintained , U.S.A., Saturday, July 14, 2018, 02:15 (2322 days ago) @ David Turell
A new theory proposes H. sapiens sprung up in several places in Africa and gradually coalesced into our current form:
https://www.theguardian.com/science/2018/jul/11/no-single-birthplace-of-mankind-say-sci...
" a team of prominent scientists is now calling for a rewriting of this traditional narrative, based on a comprehensive survey of fossil, archaeological and genetic evidence. Instead, the international team argue, the distinctive features that make us human emerged mosaic-like across different populations spanning the entire African continent. Only after tens or hundreds of thousands of years of interbreeding and cultural exchange between these semi-isolated groups, did the fully fledged modern human come into being.
***
"This continental-wide view would help reconcile contradictory interpretations of early Homo sapiens fossils varying greatly in shape, scattered from South Africa (Florisbad) to Ethiopia (Omo Kibish) to Morocco (Jebel Irhoud).
***
"The latest analysis suggests that this patchwork emergence of human traits can be explained by the existence of multiple populations that were periodically separated for millennia by rivers, deserts, forests and mountains before coming into contact again due to shifts in the climate. “These barriers created migration and contact opportunities for groups that may previously have been separated, and later fluctuation might have meant populations that mixed for a short while became isolated again,” said Scerri.
"The trend towards more sophisticated stone tools, jewellery and cooking implements also supports the theory, according to the paper...
***
“'Someone finds a skull somewhere and that’s the source of humanity. Someone finds some tools somewhere, that’s the source of humanity,” she said, describing the latest approach as: “‘Let’s be inclusive and construct a model based on all the data we have available.”
"The analysis also paints a picture of humans as a far more diverse collection of species and sub-populations than exists today. Between 200,000 and 400,000 years ago, our own ancestors lived alongside a primitive human species called Homo naledi, found in southern Africa, a larger brained species called Homo heidelbergensis in central Africa and perhaps myriad other humans yet to be discovered."
David: Comment: It is a strange thought to imagine various types of humans evolving everywhere from their ape-like ancestors, all to end up as one surviving type. Sounds like a purposeful drive. A major problem is the paucity of wide-spread homo fossils to fill in the story.
Sounds like the scattering at Babel. Within a few generations the dominant morphological traits of the group would be pretty much set. It would also explain a lot of other non-biological mysteries.
--
What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.
Human evolution; from several starting points in Africa
by David Turell , Saturday, July 14, 2018, 04:43 (2322 days ago) @ Balance_Maintained
A new theory proposes H. sapiens sprung up in several places in Africa and gradually coalesced into our current form:
https://www.theguardian.com/science/2018/jul/11/no-single-birthplace-of-mankind-say-sci...
" a team of prominent scientists is now calling for a rewriting of this traditional narrative, based on a comprehensive survey of fossil, archaeological and genetic evidence. Instead, the international team argue, the distinctive features that make us human emerged mosaic-like across different populations spanning the entire African continent. Only after tens or hundreds of thousands of years of interbreeding and cultural exchange between these semi-isolated groups, did the fully fledged modern human come into being.
***
"This continental-wide view would help reconcile contradictory interpretations of early Homo sapiens fossils varying greatly in shape, scattered from South Africa (Florisbad) to Ethiopia (Omo Kibish) to Morocco (Jebel Irhoud).
***
"The latest analysis suggests that this patchwork emergence of human traits can be explained by the existence of multiple populations that were periodically separated for millennia by rivers, deserts, forests and mountains before coming into contact again due to shifts in the climate. “These barriers created migration and contact opportunities for groups that may previously have been separated, and later fluctuation might have meant populations that mixed for a short while became isolated again,” said Scerri.
"The trend towards more sophisticated stone tools, jewellery and cooking implements also supports the theory, according to the paper...
***
“'Someone finds a skull somewhere and that’s the source of humanity. Someone finds some tools somewhere, that’s the source of humanity,” she said, describing the latest approach as: “‘Let’s be inclusive and construct a model based on all the data we have available.”
"The analysis also paints a picture of humans as a far more diverse collection of species and sub-populations than exists today. Between 200,000 and 400,000 years ago, our own ancestors lived alongside a primitive human species called Homo naledi, found in southern Africa, a larger brained species called Homo heidelbergensis in central Africa and perhaps myriad other humans yet to be discovered."
David: Comment: It is a strange thought to imagine various types of humans evolving everywhere from their ape-like ancestors, all to end up as one surviving type. Sounds like a purposeful drive. A major problem is the paucity of wide-spread homo fossils to fill in the story.
Tony: Sounds like the scattering at Babel. Within a few generations the dominant morphological traits of the group would be pretty much set. It would also explain a lot of other non-biological mysteries.
To reach one cohesive phenotype, there would have to be inter group cross breeding. How does that happen if they are scattered into small enclaves?
Human evolution; from several starting points in Africa
by Balance_Maintained , U.S.A., Saturday, July 14, 2018, 05:47 (2322 days ago) @ David Turell
A new theory proposes H. sapiens sprung up in several places in Africa and gradually coalesced into our current form:
https://www.theguardian.com/science/2018/jul/11/no-single-birthplace-of-mankind-say-sci...
" a team of prominent scientists is now calling for a rewriting of this traditional narrative, based on a comprehensive survey of fossil, archaeological and genetic evidence. Instead, the international team argue, the distinctive features that make us human emerged mosaic-like across different populations spanning the entire African continent. Only after tens or hundreds of thousands of years of interbreeding and cultural exchange between these semi-isolated groups, did the fully fledged modern human come into being.
***
"This continental-wide view would help reconcile contradictory interpretations of early Homo sapiens fossils varying greatly in shape, scattered from South Africa (Florisbad) to Ethiopia (Omo Kibish) to Morocco (Jebel Irhoud).
***
"The latest analysis suggests that this patchwork emergence of human traits can be explained by the existence of multiple populations that were periodically separated for millennia by rivers, deserts, forests and mountains before coming into contact again due to shifts in the climate. “These barriers created migration and contact opportunities for groups that may previously have been separated, and later fluctuation might have meant populations that mixed for a short while became isolated again,” said Scerri.
"The trend towards more sophisticated stone tools, jewellery and cooking implements also supports the theory, according to the paper...
***
“'Someone finds a skull somewhere and that’s the source of humanity. Someone finds some tools somewhere, that’s the source of humanity,” she said, describing the latest approach as: “‘Let’s be inclusive and construct a model based on all the data we have available.”
"The analysis also paints a picture of humans as a far more diverse collection of species and sub-populations than exists today. Between 200,000 and 400,000 years ago, our own ancestors lived alongside a primitive human species called Homo naledi, found in southern Africa, a larger brained species called Homo heidelbergensis in central Africa and perhaps myriad other humans yet to be discovered."
David: Comment: It is a strange thought to imagine various types of humans evolving everywhere from their ape-like ancestors, all to end up as one surviving type. Sounds like a purposeful drive. A major problem is the paucity of wide-spread homo fossils to fill in the story.
Tony: Sounds like the scattering at Babel. Within a few generations the dominant morphological traits of the group would be pretty much set. It would also explain a lot of other non-biological mysteries.
David: To reach one cohesive phenotype, there would have to be inter group cross breeding. How does that happen if they are scattered into small enclaves?
Trade, most likely.
--
What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.
Human evolution; from several starting points in Africa
by David Turell , Saturday, July 14, 2018, 15:18 (2322 days ago) @ Balance_Maintained
"The analysis also paints a picture of humans as a far more diverse collection of species and sub-populations than exists today. Between 200,000 and 400,000 years ago, our own ancestors lived alongside a primitive human species called Homo naledi, found in southern Africa, a larger brained species called Homo heidelbergensis in central Africa and perhaps myriad other humans yet to be discovered."
David: Comment: It is a strange thought to imagine various types of humans evolving everywhere from their ape-like ancestors, all to end up as one surviving type. Sounds like a purposeful drive. A major problem is the paucity of wide-spread homo fossils to fill in the story.
Tony: Sounds like the scattering at Babel. Within a few generations the dominant morphological traits of the group would be pretty much set. It would also explain a lot of other non-biological mysteries.
David: To reach one cohesive phenotype, there would have to be inter group cross breeding. How does that happen if they are scattered into small enclaves?
Tony: Trade, most likely.
Trade has been recognized as contact points.
Human evolution; from several starting points in Africa
by David Turell , Sunday, March 24, 2019, 20:39 (2069 days ago) @ David Turell
Mainly from East Africa with an influence from South Africa according to new research:
https://www.sciencedaily.com/releases/2019/03/190320101957.htm
"Modern Homo sapiens first arose in Africa more than 300,000 years ago, but there is great controversy amongst scholars about whether the earliest such people would have been 'just like us' in their mental capacities -- in the sense that, if they were brought up in a family from Yorkshire today, for example, would they be indistinguishable from the rest of the population? Nevertheless, archaeologists believe that people very like us were living in small communities in an Ice Age refuge on the South African coast by at least 100,000 years ago.
"Between around 100,000 and 70,000 years ago, these people left plentiful evidence that they were thinking and behaving like modern humans -- evidence for symbolism, such as the use of pigments (probably for body painting), drawings and engravings, shell beads, and tiny stone tools called microliths that might have been part of bows and arrows. Some of this evidence for what some archaeologists call "modern human behaviour" goes back even further, to more than 150,000 years.
***
"The Huddersfield-Minho team of geneticists, led by Professor Martin Richards at Huddersfield and Dr Pedro Soares in Braga, along with the eminent Cambridge archaeologist Professor Sir Paul Mellars, have studied the maternally-inherited mitochondrial DNA from Africans in unprecedented detail, and have identified a clear signal of a small-scale migration from South Africa to East Africa that took place at just that time, around 65,000 years ago. The signal is only evident today in the mitochondrial DNA. In the rest of the genome, it seems to have been eroded away to nothing by recombination -- the reshuffling of chromosomal genes between parents every generation, which doesn't affect the mitochondrial DNA -- in the intervening millennia.
"The migration signal makes good sense in terms of climate. For most of the last few hundred years, different parts of Africa have been out of step with each other in terms of the aridity of the climate. Only for a brief period at 60,000-70,000 years ago was there a window during which the continent as a whole experienced sufficient moisture to open up a corridor between the south and the east. And intriguingly, it was around 65,000 years ago that some of the signs of symbolism and technological complexity seen earlier in South Africa start to appear in the east.
"The identification of this signal opens up the possibility that a migration of a small group of people from South Africa towards the east around 65,000 years ago transmitted aspects of their sophisticated modern human culture to people in East Africa. Those East African people were biologically little different from the South Africans -- they were all modern Homo sapiens, their brains were just as advanced and they were undoubtedly cognitively ready to receive the benefits of the new ideas and upgrade. But the way it happened might not have been so very different from a modern isolated stone-age culture encountering and embracing western civilization today.
"In any case, it looks as if something happened when the groups from the South encountered the East, with the upshot being the greatest diaspora of Homo sapiens ever known -- both throughout Africa and out of Africa to settle much of Eurasia and as far as Australia within the space of only a few thousand years."
Comment: Adds to our knowledge as to how the different parts of Africa participated. Why the diapora at that point in time? Ready for it? Climate change?
Human evolution; migration to North America
by David Turell , Friday, October 06, 2023, 16:53 (412 days ago) @ Balance_Maintained
About 21,000 years ago:
https://www.science.org/doi/full/10.1126/science.adk2495?utm_source=sfmc&utm_medium...
"Footprints scattered across what is now the desert of New Mexico were trod by human feet no earlier than 21,500 years ago, new research has confirmed.
"The venerable age of these ancient traces in White Sands, New Mexico was revealed in 2021, to much awe and more than a little skepticism. Now, a team including some of the same scientists has performed more rigorous dating, confirming the controversial result.
***
"'The immediate reaction in some circles of the archeological community was that the accuracy of our dating was insufficient to make the extraordinary claim that humans were present in North America during the Last Glacial Maximum," explains geologist Jeff Pigati of the US Geological Survey (USGS), who co-led the new effort.
"'But our targeted methodology in this current research really paid off."
"The original dating, which found the footprints dated to between 21,000 and 23,000 years ago, was based on radiocarbon dating of seeds of an aquatic plant called Ruppia cirrhosa – spiral ditchgrass – that were found embedded in the fossilized prints.
"Radiocarbon is a radioactive form of carbon, or C-14, that forms high up in Earth's atmosphere as cosmic rays collide with nitrogen. Earth is being constantly, gently rained on by C-14, which is taken up into plants and animals while they live.
"Since C-14 decays into stable carbon at a known rate, scientists can look at the ratios of C-14 to stable carbon in a sample and determine the age of that sample.
"The team's 2021 findings were questioned because of the aquatic nature of the plant on which they based their findings.
***
"The team collected conifer pollen from the same geological layer as the ditchgrass seeds, meaning that it was likely deposited at the same time. However, conifers are terrestrial, which means any carbon fixed therein would have been atmospheric carbon, and is not subject to the same error margin as aquatic carbon.
"For each of three samples, the team isolated around 75,000 pollen grains, and performed radiocarbon dating.
"They also performed a different kind of dating on quartz found in the footprint layers. Optically stimulated luminescence is a dating technique that allows scientists to determine how long ago a mineral sample was last exposed to sunlight.
"Both results were entirely consistent with the earlier findings. The conifer pollen ranged from 22,600 to 23,400 years ago, and the quartz last saw sunlight around 21,500 years ago.
"Add those results to the ditchgrass and we have three separate lines of evidence pointing to the same conclusion – a conclusion that can help us better understand the history of human migration and habitation on this ever-changing planet.
"'Our new ages, combined with the strong geologic, hydrologic, and stratigraphic evidence," Springer says, "unequivocally support the conclusion that humans were present in North America during the last Glacial Maximum.'"
Comment: human migration always was out of Africa moving East. New Mexico is an inland state, which means the true arrival was several thousand years before the footprint dates.
Human evolution; our complex speech mechanism
by David Turell , Sunday, November 18, 2018, 15:06 (2195 days ago) @ David Turell
As explored by an artificial simulation of how the brain probably handles language grammar:
http://maxplanck.nautil.us/article/341/brainwaves-encode-the-grammar-of-human-language?...
"Every day you hear at least some utterances you’ve never heard before. That you can understand them is partly due to the fact that they are structured according to grammatical rules. Scientists have found that the human brain may use the relative timing of brainwaves to encode and decode the structures in a sentence.
"Grammar is a way of structuring information that makes language an efficient way to communicate. Knowing the grammatical rules of our language allows us to say pretty much anything we want, including things we have never heard before by combining words to (new) sentences. Being able to learn and use grammar is unique to humans. But it also creates a challenge for the science of how the brain processes human language—how do our brains, essentially a bunch of cells in a network, represent something as abstract as grammatical rules?
"Scientists at the University of Edinburgh and the Max Planck Institute for Psycholinguistics study this question with the help of computer-based models. They constructed an artificial neural network that simulates key features of the brain, such as densely connected populations of neurons that show neural oscillations. Neural oscillations are wave-like patterns of activity that happen at different frequencies, some very fast and some slow. The relative timing of these neural oscillations can help the brain encode grammatical relationships between words in a sentence, as Andrea Martin and Leonidas Doumas report in a paper in PLOS Biology.
"By encoding words in one oscillation, and phrases in another, the brain can keep track of words and phrases at the same time. This demonstrates how something as complex as a sentence can be encoded in the neural currency of oscillations. A key finding of the new study is that these artificial neural networks, when fed example sentences, give off patterns of energy that mimic what the brain does when it processes a sentence. Martin, lead author of the study, says: “This work helps us understand how the brain solves a complex puzzle and why it gives off the activity patterns that it does when processing language.”
"In this exciting age of the brain, where we know more about our brains than ever before, being able to link basic experiences like speaking and understanding language directly to brain function is especially important. Linking our brains to our behaviors holds the key to understanding not only what it means to be human, but also to understanding how the (arguably) most complex computing device in the universe, the human brain, gives rise to our daily experiences. Such knowledge may also lead to biologically inspired advances in human-like artificial intelligence and computation."
Comment: A computer simulation that actually mimics the actual brain wave patterns, suggests this result is a true representation of how brain plasticity has adapted to handle language grammar. In describing the brain as 'arguably' the most complex, the article fudges on accepting that the brain is obviously the most complex result of evolution.
Human evolution; our complex speech mechanism
QUOTE: "In this exciting age of the brain, where we know more about our brains than ever before, being able to link basic experiences like speaking and understanding language directly to brain function is especially important. Linking our brains to our behaviors holds the key to understanding not only what it means to be human, but also to understanding how the (arguably) most complex computing device in the universe, the human brain, gives rise to our daily experiences."
DAVID’s comment: A computer simulation that actually mimics the actual brain wave patterns, suggests this result is a true representation of how brain plasticity has adapted to handle language grammar. In describing the brain as 'arguably' the most complex, the article fudges on accepting that the brain is obviously the most complex result of evolution.
Perhaps more to the point in the context of so many of our discussions, it fudges on the origin of the consciousness that determines what use we make of language. It states explicitly that the brain gives rise to our daily experiences. I think most dualists would argue that our daily experiences are the result of the interaction between brain and soul. (I remain neutral on the subject.)
Human evolution; our complex speech mechanism
by David Turell , Monday, November 19, 2018, 15:08 (2194 days ago) @ dhw
QUOTE: "In this exciting age of the brain, where we know more about our brains than ever before, being able to link basic experiences like speaking and understanding language directly to brain function is especially important. Linking our brains to our behaviors holds the key to understanding not only what it means to be human, but also to understanding how the (arguably) most complex computing device in the universe, the human brain, gives rise to our daily experiences."
DAVID’s comment: A computer simulation that actually mimics the actual brain wave patterns, suggests this result is a true representation of how brain plasticity has adapted to handle language grammar. In describing the brain as 'arguably' the most complex, the article fudges on accepting that the brain is obviously the most complex result of evolution.
dhw: Perhaps more to the point in the context of so many of our discussions, it fudges on the origin of the consciousness that determines what use we make of language. It states explicitly that the brain gives rise to our daily experiences. I think most dualists would argue that our daily experiences are the result of the interaction between brain and soul. (I remain neutral on the subject.)
The article has obvious limitations, since it is a reductionist study of how the brain has modified to handle language and speech.
Human evolution; stone tools very early in Asia
by David Turell , Tuesday, November 20, 2018, 18:49 (2193 days ago) @ David Turell
A type of advanced stone tool is now found in Asia and dated to as much as 130-180,000 years ago:
https://www.sciencedaily.com/releases/2018/11/181119160256.htm
"A study by an international team of researchers, including from the University of Washington, determines that carved stone tools, also known as Levallois cores, were used in Asia 80,000 to 170,000 years ago. Developed in Africa and Western Europe as far back as 300,000 years ago, the cores are a sign of more-advanced toolmaking -- the "multi-tool" of the prehistoric world -- but, until now, were not believed to have emerged in East Asia until 30,000 to 40,000 years ago.
"With the find -- and absent human fossils linking the tools to migrating populations -- researchers believe people in Asia developed the technology independently, evidence of similar sets of skills evolving throughout different parts of the ancient world.
***
"Levallois-shaped cores -- the "Swiss Army knife of prehistoric tools," Marwick said -- were efficient and durable, indispensable to a hunter-gatherer society in which a broken spear point could mean certain death at the claws or jaws of a predator. The cores were named for the Levallois-Perret suburb of Paris, where stone flakes were found in the 1800s.
***
"The researchers analyzed more than 2,200 artifacts found at Guanyindong Cave, narrowing down the number of Levallois-style stone cores and flakes to 45. Among those believed to be in the older age range, about 130,000 to 180,000 years old, the team also was able to identify the environment in which the tools were used: an open woodland on a rocky landscape, in "a reduced rainforest area compared to today," the authors note.
"In Africa and Europe these kinds of stone tools are often found at archaeological sites starting from 300,000 and 200,000 years ago. They are known as Mode III technology, part of a broad evolutionary sequence that was preceded by hand-axe technology (Mode II) and followed by blade tool technology (Mode IV). Archaeologists thought that Mode IV technologies arrived in China by migration from the West, but these new finds suggest they could have been locally invented. At the time people were making tools in Guanyindong Cave, the Denisovans -- ancestors to Homo sapiens and relative contemporaries to Neandertals elsewhere in the world -- roamed East Asia. But while hundreds of fossils of archaic humans and related artifacts, dating as far back as more than 3 million years ago, have been found in Africa and Europe, the archaeological record in East Asia is sparser.
***
"In the evolution of tools, Levallois cores represent something of a middle stage. Subsequent manufacturing processes yielded more-refined blades made of rocks and minerals that were more resistant to flaking, and composites that, for example, combined a spear point with blades along the edge. The appearance of blades later in time indicates a further increase in the complexity and the number of steps required to make the tools.
"'The appearance of the Levallois strategy represents a big increase in the complexity of technology because there are so many steps that have to work in order to get the final product, compared to previous technologies," Marwick said."
Comment: It looks as if advanced H. sapiens were more widespread over the world than just Africa and then Europe.
Human evolution; exercise helps the brain
by David Turell , Friday, November 23, 2018, 21:03 (2190 days ago) @ David Turell
We are still hunter-gatherers who evolved bodies to be maintained by exercise activities:
https://www.the-scientist.com/features/this-is-your-brain-on-exercise-64934
"Researchers have long recognized that exercise sharpens certain cognitive skills. Indeed, Maejima and his colleagues have found that regular physical activity improves mice’s ability to distinguish new objects from ones they’ve seen before. Over the past 20 years, researchers have begun to get at the root of these benefits, with studies pointing to increases in the volume of the hippocampus, development of new neurons, and infiltration of blood vessels into the brain. Now, Maejima and others are starting to home in on the epigenetic mechanisms that drive the neurological changes brought on by physical activity.
***
" Moses Chao, a molecular neurobiologist at the New York University School of Medicine, and colleagues recently found that mice that ran frequently on wheels had higher levels of BDNF and of a ketone that’s a byproduct of fat metabolism released from the liver. Injecting the ketone into the brains of mice that did not run helped to inhibit histone deacetylases and increased Bdnf expression in the hippocampus. The finding shows how molecules can travel through the blood, cross the blood-brain barrier, and activate or inhibit epigenetic markers in the brain.
***
"The result also offers support for the 58 clinical trials currently being done on exercise, cognition, and Alzheimer’s disease. There are nearly 100 ongoing trials, including Petzinger’s, investigating exercise’s role in easing Parkinson’s symptoms, and hundreds more looking at exercise as an intervention against depression. Some researchers are even testing the effects of exercise on aging.
“'An active lifestyle is not going to turn a 70-year-old brain into a 30-year-old brain,” says Petzinger. “But studying exercise’s effect on the nervous system could help researchers identify the best and most efficient strategy—whether it’s activity alone or activity paired with drugs—to maintain brain health as we age.'”
Comment: And the same thought applies to muscle health, since we are now not hunter-gatherers:
https://www.the-scientist.com/features/how-muscles-age--and-how-exercise-can-slow-it-64708
"In 1988, Tufts University’s Irwin Rosenberg coined the term “sarcopenia” from Greek roots to describe this age-related lack (penia) of flesh (sarx). Muscle aging likely has several underlying factors, including decreased numbers of muscle stem cells, mitochondrial dysfunction, a decline in protein quality and turnover, and hormonal deregulation. Loss of muscle mass is associated with—and possibly preceded by—muscle weakness, which can make carrying out daily activities, such as climbing stairs or even getting up from a chair, difficult for many seniors. This can lead to inactivity, which itself leads to muscle loss at any age. Thus, older people can enter a vicious cycle that will eventually lead to an increased risk of falls, a loss of independence, and even premature death.
"The good news is that exercise can stave off and even reverse muscle loss and weakness. Recent research has demonstrated that physical activity can promote mitochondrial health, increase protein turnover, and restore levels of signaling molecules involved in muscle function. But while scientists know a lot about what goes wrong in aging, and know that exercise can slow the inevitable, the details of this relationship are just starting to come into focus.
***
"Although the causes of muscle loss are numerous and complex, there is now copious evidence to suggest that exercise may prevent or reverse many of these age-related changes, whereas inactivity will accelerate muscle aging. Earlier this year, for example, Janet Lord of the University of Birmingham and Steven Harridge at King’s College London examined the muscles of 125 male and female amateur cyclists and showed that a lifetime of regular exercise can slow down muscle aging: there were no losses in muscle mass or muscle strength among those who were older and exercised regularly. More surprisingly, the immune system had not aged much either.
"Exercise’s influence on muscle health likely acts through as many mechanisms as those underlying age-related muscle loss and weakness. For example, the number of satellite cells can be increased by exercise, and active elderly people have more of these cells than more-sedentary individuals do. This is the reason why exercise prior to hip and knee surgery can speed up recovery in the elderly.
"Physical activity also affects the muscle’s mitochondria. A lack of exercise decreases the efficiency and number of mitochondria in skeletal muscle, while exercise promotes mitochondrial health.
***
"For now, regular exercise combined with good nutrition is still the most effective way to fight sarcopenia, and possibly aging overall."
Comment: The articles are filled with biochemical studies, if interested.
Human evolution; our complex speech mechanism
by David Turell , Sunday, November 25, 2018, 19:18 (2188 days ago) @ David Turell
Recognizing speech starts in the womb. We are obviously programmed for language:
http://maxplanck.nautil.us/article/342/from-a-babys-cry-to-goethes-faust?utm_source=Nau...
"Speech is generally believed to start with our very first cry at the moment we enter the world. In fact, however, it begins much earlier. We can already understand individual sounds in the womb. From then on, it would appear that speech develops paradoxically in the course of life: We reach many milestones at a blazing pace in the first three years of life, while other language skills do not develop fully until adulthood. For the first time, scientists at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig have described the exact nature of this path in a comprehensive model. The model is based on an innovative method that sheds light on how a 3-year-old’s brain processes speech.
"It might appear paradoxical: On the one hand, even newborn babies are able to distinguish acoustically between individual syllables such as “ma” and “pa,” and 3-year-olds can already understand simple sentences effortlessly. On the other hand, the ability to understand complicated formulations without difficulty, even if they consist of simple words, only develops in adulthood.
***
“'The regions of the brain responsible for processing speech and the connection between them, a kind of data highway, mature at different rates,” as Angela D. Friederici, director of the Leipzig-based Max Planck Institute, explains.
***
"According to the model, a specific region of the cerebrum is involved in speech processing from the outset. Known as the left temporal lobe of the cerebrum, it enables us to differentiate “mama” from “papa” automatically in the space of just a few thousandths of a second. It can already process simple sentences consisting of a few words. Until around the age of 3, the temporal lobe is therefore the epicenter of speech.
"Only then is it gradually joined by a second central speech region, which forms part of the overall speech network, namely Broca’s area, which is located in the frontal region of the cerebrum. It is here that complex linguistic information is processed.
***
"With increasing age, Broca’s area is not only more strongly activated during speech processing, but also becomes more closely integrated in the overall speech network. This ability crucially depends on a bundle of nerve fibers known as the arcuate fasciculus, which forms a connection between these two speech centers, the left temporal lobe and Broca’s area. Only when this bundle of nerve fibers is mature are we able to process complicated sentences as quickly and efficiently as simple sentences. That does not happen until roughly toward the end of puberty.
***
"The findings were obtained thanks to an innovative method that was elaborated at the Max Planck Institute in Leipzig. “For a long time, our knowledge of how the brain develops the ability to process complex language was sketchy. It seemed impossible to look into the brains of young children while they are processing speech,” she explains. It was thought that the usual technique of magnetic resonance imaging (MRI) is unsuitable for young children—especially because they find it difficult to hold their head still during the procedure.
"Friederici and her team succeeded in refining MRI measurements to the extent that it is now possible to peer into the brains of 3-year-olds. The key idea behind their method was to combine business with pleasure. They practiced keeping still with children as a game while the children watched an animated film. “This method paved the way for our current understanding of the development of our speech network,” she adds."
Comment: We come into this world ready to learn how to understand language. Of course I think designed that way .
Human evolution; our complex speech mechanism
QUOTES: “'The regions of the brain responsible for processing speech and the connection between them, a kind of data highway, mature at different rates,” as Angela D. Friederici, director of the Leipzig-based Max Planck Institute, explains.
***
"According to the model, a specific region of the cerebrum is involved in speech processing from the outset. Known as the left temporal lobe of the cerebrum, it enables us to differentiate “mama” from “papa” automatically in the space of just a few thousandths of a second. It can already process simple sentences consisting of a few words. Until around the age of 3, the temporal lobe is therefore the epicenter of speech.
"Only then is it gradually joined by a second central speech region, which forms part of the overall speech network, namely Broca’s area, which is located in the frontal region of the cerebrum. It is here that complex linguistic information is processed.”
I can only go on thanking you for the astonishing range of articles you keep presenting to us, bringing us up to date with the latest findings in so many areas of our discussions.
This article makes me wonder if the current individual evolution of the brain does not mirror its historical evolution. Leaving aside the great divide between dualism and materialism, we have concepts requiring expression and the brain developing as the range of concepts expands. Currently these concepts are learned, but each one originally had to be invented. The implementation of each invention historically would have required new neurons and new connections, and now individually the learning does the same. Similarly, the embryo itself starts out as a throwback to our animal ancestry and then “evolves” into our current human form. (In passing, this can also be seen as a clear pointer to common descent.)
Human evolution; our complex speech mechanism
by David Turell , Monday, November 26, 2018, 19:05 (2187 days ago) @ dhw
QUOTES: “'The regions of the brain responsible for processing speech and the connection between them, a kind of data highway, mature at different rates,” as Angela D. Friederici, director of the Leipzig-based Max Planck Institute, explains.
***
"According to the model, a specific region of the cerebrum is involved in speech processing from the outset. Known as the left temporal lobe of the cerebrum, it enables us to differentiate “mama” from “papa” automatically in the space of just a few thousandths of a second. It can already process simple sentences consisting of a few words. Until around the age of 3, the temporal lobe is therefore the epicenter of speech.
"Only then is it gradually joined by a second central speech region, which forms part of the overall speech network, namely Broca’s area, which is located in the frontal region of the cerebrum. It is here that complex linguistic information is processed.”dhw: I can only go on thanking you for the astonishing range of articles you keep presenting to us, bringing us up to date with the latest findings in so many areas of our discussions.
This article makes me wonder if the current individual evolution of the brain does not mirror its historical evolution. Leaving aside the great divide between dualism and materialism, we have concepts requiring expression and the brain developing as the range of concepts expands. Currently these concepts are learned, but each one originally had to be invented. The implementation of each invention historically would have required new neurons and new connections, and now individually the learning does the same. Similarly, the embryo itself starts out as a throwback to our animal ancestry and then “evolves” into our current human form. (In passing, this can also be seen as a clear pointer to common descent.)
The brain is designed to provide these necessary areas to take over the jobs required by language: speech, writing, reading, typing, etc. The chimp does none of this, but has comparative areas they never put use, because they cannot. Our brain advances are not explained by chance evolution. We are obviously designed.
Human evolution; our complex speech mechanism
Dhw: This article makes me wonder if the current individual evolution of the brain does not mirror its historical evolution. Leaving aside the great divide between dualism and materialism, we have concepts requiring expression and the brain developing as the range of concepts expands. Currently these concepts are learned, but each one originally had to be invented. The implementation of each invention historically would have required new neurons and new connections, and now individually the learning does the same. Similarly, the embryo itself starts out as a throwback to our animal ancestry and then “evolves” into our current human form. (In passing, this can also be seen as a clear pointer to common descent.)
DAVID: The brain is designed to provide these necessary areas to take over the jobs required by language: speech, writing, reading, typing, etc. The chimp does none of this, but has comparative areas they never put use, because they cannot. Our brain advances are not explained by chance evolution. We are obviously designed.
My post has nothing to do with chance versus design. I am pointing out the parallel between the development of the current individual brain and the historical development of the brain from pre-sapiens to sapiens. In each case the implementation of new concepts is what changes the structure. This can actually be observed today, and there is no reason to suppose that the same process did not take place in pre-humans.
My “in passing” comment could be added to the discussion under “Innovation, Speciation”.
Human evolution; our complex speech mechanism
by David Turell , Tuesday, November 27, 2018, 17:21 (2186 days ago) @ dhw
Dhw: This article makes me wonder if the current individual evolution of the brain does not mirror its historical evolution. Leaving aside the great divide between dualism and materialism, we have concepts requiring expression and the brain developing as the range of concepts expands. Currently these concepts are learned, but each one originally had to be invented. The implementation of each invention historically would have required new neurons and new connections, and now individually the learning does the same. Similarly, the embryo itself starts out as a throwback to our animal ancestry and then “evolves” into our current human form. (In passing, this can also be seen as a clear pointer to common descent.)
DAVID: The brain is designed to provide these necessary areas to take over the jobs required by language: speech, writing, reading, typing, etc. The chimp does none of this, but has comparative areas they never put use, because they cannot. Our brain advances are not explained by chance evolution. We are obviously designed.
dhw: My post has nothing to do with chance versus design. I am pointing out the parallel between the development of the current individual brain and the historical development of the brain from pre-sapiens to sapiens. In each case the implementation of new concepts is what changes the structure. This can actually be observed today, and there is no reason to suppose that the same process did not take place in pre-humans.
What can a new concept to act upon or do if the newly needed structure is not in place? Cart before horse.
Human evolution; our complex speech mechanism
Dhw: This article makes me wonder if the current individual evolution of the brain does not mirror its historical evolution. Leaving aside the great divide between dualism and materialism, we have concepts requiring expression and the brain developing as the range of concepts expands. Currently these concepts are learned, but each one originally had to be invented. The implementation of each invention historically would have required new neurons and new connections, and now individually the learning does the same. Similarly, the embryo itself starts out as a throwback to our animal ancestry and then “evolves” into our current human form. (In passing, this can also be seen as a clear pointer to common descent.)
DAVID: The brain is designed to provide these necessary areas to take over the jobs required by language: speech, writing, reading, typing, etc. The chimp does none of this, but has comparative areas they never put use, because they cannot. Our brain advances are not explained by chance evolution. We are obviously designed.
dhw: My post has nothing to do with chance versus design. I am pointing out the parallel between the development of the current individual brain and the historical development of the brain from pre-sapiens to sapiens. In each case the implementation of new concepts is what changes the structure. This can actually be observed today, and there is no reason to suppose that the same process did not take place in pre-humans.
DAVID: What can a new concept to act upon or do if the newly needed structure is not in place? Cart before horse.
It is implementation of concepts new to the individual that creates new neurons and new connections as the person learns. I thought you had accepted this, as it was clearly illustrated by the examples of the Indian women, taxi drivers, musicians. We do not know where the original concepts come from, but I am not trying to restart the discussion on materialism versus dualism, and should not have opened the door to that particular subject. My apologies. I am simply wondering (pure conjecture) whether the “evolution” of the individual’s brain as it adds and complexifies through childhood and into adulthood mirrors the evolution of the brain through history, with its additions and complexifications – just as the “evolution” of the individual embryo appears to relive (that might be a better term) at least part of the history of human evolution. It’s just a thought that struck me. Maybe the idea is too fanciful?
Human evolution; our complex speech mechanism
by David Turell , Wednesday, November 28, 2018, 18:15 (2185 days ago) @ dhw
Dhw: This article makes me wonder if the current individual evolution of the brain does not mirror its historical evolution. Leaving aside the great divide between dualism and materialism, we have concepts requiring expression and the brain developing as the range of concepts expands. Currently these concepts are learned, but each one originally had to be invented. The implementation of each invention historically would have required new neurons and new connections, and now individually the learning does the same. Similarly, the embryo itself starts out as a throwback to our animal ancestry and then “evolves” into our current human form. (In passing, this can also be seen as a clear pointer to common descent.)
DAVID: The brain is designed to provide these necessary areas to take over the jobs required by language: speech, writing, reading, typing, etc. The chimp does none of this, but has comparative areas they never put use, because they cannot. Our brain advances are not explained by chance evolution. We are obviously designed.
dhw: My post has nothing to do with chance versus design. I am pointing out the parallel between the development of the current individual brain and the historical development of the brain from pre-sapiens to sapiens. In each case the implementation of new concepts is what changes the structure. This can actually be observed today, and there is no reason to suppose that the same process did not take place in pre-humans.
DAVID: What can a new concept to act upon or do if the newly needed structure is not in place? Cart before horse.
dhw: It is implementation of concepts new to the individual that creates new neurons and new connections as the person learns. I thought you had accepted this, as it was clearly illustrated by the examples of the Indian women, taxi drivers, musicians. We do not know where the original concepts come from, but I am not trying to restart the discussion on materialism versus dualism, and should not have opened the door to that particular subject. My apologies. I am simply wondering (pure conjecture) whether the “evolution” of the individual’s brain as it adds and complexifies through childhood and into adulthood mirrors the evolution of the brain through history, with its additions and complexifications – just as the “evolution” of the individual embryo appears to relive (that might be a better term) at least part of the history of human evolution. It’s just a thought that struck me. Maybe the idea is too fanciful?
You've jumped to minor plasticity in newly literate Indian women using a very complex brain they were given and plastically changed a little. Speech requires the complexity of the human brain starting 300,000 years ago. The eventually completed complex brain takes until 25 years old and may in part (I agree with you) mimic evolution of it.
Human evolution; our complex speech mechanism
DAVID: What can a new concept to act upon or do if the newly needed structure is not in place? Cart before horse.
dhw: It is implementation of concepts new to the individual that creates new neurons and new connections as the person learns. I thought you had accepted this, as it was clearly illustrated by the examples of the Indian women, taxi drivers, musicians. We do not know where the original concepts come from, but I am not trying to restart the discussion on materialism versus dualism, and should not have opened the door to that particular subject. My apologies. I am simply wondering (pure conjecture) whether the “evolution” of the individual’s brain as it adds and complexifies through childhood and into adulthood mirrors the evolution of the brain through history, with its additions and complexifications – just as the “evolution” of the individual embryo appears to relive (that might be a better term) at least part of the history of human evolution. It’s just a thought that struck me. Maybe the idea is too fanciful?
DAVID: You've jumped to minor plasticity in newly literate Indian women using a very complex brain they were given and plastically changed a little. Speech requires the complexity of the human brain starting 300,000 years ago. The eventually completed complex brain takes until 25 years old and may in part (I agree with you) mimic evolution of it.
No one would doubt that speech requires greater complexity than non-speech, but we needn’t go over all that again. Thank you for your agreement that individual evolution may mirror/relive/mimic historical evolution. This ties in with a vague concept I have of microcosms mirroring macrocosms, but this would be a colossal field that you are certainly better equipped to explore than I am.
Human evolution; our complex speech mechanism
by David Turell , Thursday, November 29, 2018, 15:23 (2184 days ago) @ dhw
DAVID: What can a new concept to act upon or do if the newly needed structure is not in place? Cart before horse.
dhw: It is implementation of concepts new to the individual that creates new neurons and new connections as the person learns. I thought you had accepted this, as it was clearly illustrated by the examples of the Indian women, taxi drivers, musicians. We do not know where the original concepts come from, but I am not trying to restart the discussion on materialism versus dualism, and should not have opened the door to that particular subject. My apologies. I am simply wondering (pure conjecture) whether the “evolution” of the individual’s brain as it adds and complexifies through childhood and into adulthood mirrors the evolution of the brain through history, with its additions and complexifications – just as the “evolution” of the individual embryo appears to relive (that might be a better term) at least part of the history of human evolution. It’s just a thought that struck me. Maybe the idea is too fanciful?
DAVID: You've jumped to minor plasticity in newly literate Indian women using a very complex brain they were given and plastically changed a little. Speech requires the complexity of the human brain starting 300,000 years ago. The eventually completed complex brain takes until 25 years old and may in part (I agree with you) mimic evolution of it.
dhw: No one would doubt that speech requires greater complexity than non-speech, but we needn’t go over all that again. Thank you for your agreement that individual evolution may mirror/relive/mimic historical evolution. This ties in with a vague concept I have of microcosms mirroring macrocosms, but this would be a colossal field that you are certainly better equipped to explore than I am.
It is certainly true that a bacterium in its membrane lives and does many of the same things our bodies with its trillions of different cells does. Simple yeast cells teach us much about how cells work. 'Nough said.
Human evolution; our complex speech mechanism
Dhw: Thank you for your agreement that individual evolution may mirror/relive/mimic historical evolution. This ties in with a vague concept I have of microcosms mirroring macrocosms, but this would be a colossal field that you are certainly better equipped to explore than I am.
DAVID: It is certainly true that a bacterium in its membrane lives and does many of the same things our bodies with its trillions of different cells does. Simple yeast cells teach us much about how cells work. 'Nough said.
Thank you. An excellent example. It’s a theme I would love to develop, ranging from microorganisms to the universe itself and, of course, a possible God. But it is too vast for me to embark on.
Human evolution; our complex speech mechanism
by David Turell , Friday, November 30, 2018, 15:41 (2183 days ago) @ dhw
Dhw: Thank you for your agreement that individual evolution may mirror/relive/mimic historical evolution. This ties in with a vague concept I have of microcosms mirroring macrocosms, but this would be a colossal field that you are certainly better equipped to explore than I am.
DAVID: It is certainly true that a bacterium in its membrane lives and does many of the same things our bodies with its trillions of different cells does. Simple yeast cells teach us much about how cells work. 'Nough said.
dhw: Thank you. An excellent example. It’s a theme I would love to develop, ranging from microorganisms to the universe itself and, of course, a possible God. But it is too vast for me to embark on.
The universe started with a Big Bang. Are the first living cells a 'big bang' start for life?
Human evolution; our complex speech mechanism
Dhw: Thank you for your agreement that individual evolution may mirror/relive/mimic historical evolution. This ties in with a vague concept I have of microcosms mirroring macrocosms, but this would be a colossal field that you are certainly better equipped to explore than I am.
DAVID: It is certainly true that a bacterium in its membrane lives and does many of the same things our bodies with its trillions of different cells does. Simple yeast cells teach us much about how cells work. 'Nough said.
dhw: Thank you. An excellent example. It’s a theme I would love to develop, ranging from microorganisms to the universe itself and, of course, a possible God. But it is too vast for me to embark on.
DAVID: The universe started with a Big Bang. Are the first living cells a 'big bang' start for life?
I’m not sure if the universe started with a Big Bang, but it’s nice that you’re also looking for parallels.
Human evolution; our complex speech mechanism
by David Turell , Saturday, December 01, 2018, 18:19 (2182 days ago) @ dhw
Dhw: Thank you for your agreement that individual evolution may mirror/relive/mimic historical evolution. This ties in with a vague concept I have of microcosms mirroring macrocosms, but this would be a colossal field that you are certainly better equipped to explore than I am.
DAVID: It is certainly true that a bacterium in its membrane lives and does many of the same things our bodies with its trillions of different cells does. Simple yeast cells teach us much about how cells work. 'Nough said.
dhw: Thank you. An excellent example. It’s a theme I would love to develop, ranging from microorganisms to the universe itself and, of course, a possible God. But it is too vast for me to embark on.
DAVID: The universe started with a Big Bang. Are the first living cells a 'big bang' start for life?
dhw: I’m not sure if the universe started with a Big Bang, but it’s nice that you’re also looking for parallels.
At least we are looking at two of the most major starts of all starts. Can you think of a third?
Human evolution; our complex speech mechanism
Dhw: Thank you for your agreement that individual evolution may mirror/relive/mimic historical evolution. This ties in with a vague concept I have of microcosms mirroring macrocosms, but this would be a colossal field that you are certainly better equipped to explore than I am.
DAVID: It is certainly true that a bacterium in its membrane lives and does many of the same things our bodies with its trillions of different cells does. Simple yeast cells teach us much about how cells work. 'Nough said.
dhw: Thank you. An excellent example. It’s a theme I would love to develop, ranging from microorganisms to the universe itself and, of course, a possible God. But it is too vast for me to embark on.
DAVID: The universe started with a Big Bang. Are the first living cells a 'big bang' start for life?
dhw: I’m not sure if the universe started with a Big Bang, but it’s nice that you’re also looking for parallels.
DAVID: At least we are looking at two of the most major starts of all starts. Can you think of a third?
The start of our solar system and Planet Earth was pretty major for you and me, but an eternal and infinite universe could have had an infinite number of major starts.
Human evolution; our complex speech mechanism
by David Turell , Sunday, December 02, 2018, 15:16 (2181 days ago) @ dhw
Dhw: Thank you for your agreement that individual evolution may mirror/relive/mimic historical evolution. This ties in with a vague concept I have of microcosms mirroring macrocosms, but this would be a colossal field that you are certainly better equipped to explore than I am.
DAVID: It is certainly true that a bacterium in its membrane lives and does many of the same things our bodies with its trillions of different cells does. Simple yeast cells teach us much about how cells work. 'Nough said.
dhw: Thank you. An excellent example. It’s a theme I would love to develop, ranging from microorganisms to the universe itself and, of course, a possible God. But it is too vast for me to embark on.
DAVID: The universe started with a Big Bang. Are the first living cells a 'big bang' start for life?
dhw: I’m not sure if the universe started with a Big Bang, but it’s nice that you’re also looking for parallels.
DAVID: At least we are looking at two of the most major starts of all starts. Can you think of a third?
dhw: The start of our solar system and Planet Earth was pretty major for you and me, but an eternal and infinite universe could have had an infinite number of major starts.
Up to this point we were talking about possibilities with significant evidence. The eternal and infinite universe is pure hypothesis and without a smidgen of evidence.
Human evolution; our complex speech mechanism
DAVID: The universe started with a Big Bang. Are the first living cells a 'big bang' start for life?
dhw: I’m not sure if the universe started with a Big Bang, but it’s nice that you’re also looking for parallels.
DAVID: At least we are looking at two of the most major starts of all starts. Can you think of a third?
dhw: The start of our solar system and Planet Earth was pretty major for you and me, but an eternal and infinite universe could have had an infinite number of major starts.
DAVID: Up to this point we were talking about possibilities with significant evidence. The eternal and infinite universe is pure hypothesis and without a smidgen of evidence.
Fair comment. I should have stuck to our solar system and planet. Apologies for taking us off onto a different track. An interesting one, though. One has to ask: what was there before the Big Bang, if it ever happened? Nothing at all is also pure hypothesis, as is an eternal mind without a beginning. There is no way we shall ever know, unless your pure hypothesis is correct and your God reveals himself!
Human evolution; our complex speech mechanism
by David Turell , Monday, December 03, 2018, 16:55 (2180 days ago) @ dhw
DAVID: The universe started with a Big Bang. Are the first living cells a 'big bang' start for life?
dhw: I’m not sure if the universe started with a Big Bang, but it’s nice that you’re also looking for parallels.
DAVID: At least we are looking at two of the most major starts of all starts. Can you think of a third?
dhw: The start of our solar system and Planet Earth was pretty major for you and me, but an eternal and infinite universe could have had an infinite number of major starts.
DAVID: Up to this point we were talking about possibilities with significant evidence. The eternal and infinite universe is pure hypothesis and without a smidgen of evidence.
dhw: Fair comment. I should have stuck to our solar system and planet. Apologies for taking us off onto a different track. An interesting one, though. One has to ask: what was there before the Big Bang, if it ever happened? Nothing at all is also pure hypothesis, as is an eternal mind without a beginning. There is no way we shall ever know, unless your pure hypothesis is correct and your God reveals himself!
According to Guth and his cohorts there is no 'before' before the Big Bang, proven mathematically in a paper presented in 2002 at Hawkings 60th birthday party/ symposium, my book, page 63. Put simply, time starts with the BB. Just as life starts with the first functional living cell. Both starts are followed by an evolutionary process which are too complex to be the result of chance. If there is a cause for each event, it is simpler to attribute them to one source than to conjure up two causes for two such pivotal creations.
Human evolution; our complex speech mechanism
dhw: The start of our solar system and Planet Earth was pretty major for you and me, but an eternal and infinite universe could have had an infinite number of major starts.
DAVID: Up to this point we were talking about possibilities with significant evidence. The eternal and infinite universe is pure hypothesis and without a smidgen of evidence.
dhw: Fair comment. I should have stuck to our solar system and planet. Apologies for taking us off onto a different track. An interesting one, though. One has to ask: what was there before the Big Bang, if it ever happened? Nothing at all is also pure hypothesis, as is an eternal mind without a beginning. There is no way we shall ever know, unless your pure hypothesis is correct and your God reveals himself!
DAVID: According to Guth and his cohorts there is no 'before' before the Big Bang, proven mathematically in a paper presented in 2002 at Hawkings 60th birthday party/ symposium, my book, page 63. Put simply, time starts with the BB. Just as life starts with the first functional living cell. Both starts are followed by an evolutionary process which are too complex to be the result of chance. If there is a cause for each event, it is simpler to attribute them to one source than to conjure up two causes for two such pivotal creations.
A strange volte face. According to you, your God caused the BB, and so he existed before the BB. Before, now and after are one concept of time. Nobody can possibly prove anything about what happened before the BB (if it happened). I agree that one cause is simpler than two causes. The one cause may be an eternal and infinite universe of energy and matter constantly changing itself. No, I don’t believe it, and I don’t disbelieve it, just as I don’t believe or disbelieve in a single, conscious, sourceless, eternal mind. Maybe the complex evolutionary process was created (top down), or maybe it evolved (bottom up).
Human evolution; hominins late in Arabia
by David Turell , Tuesday, December 04, 2018, 18:01 (2179 days ago) @ dhw
New stone tool findings:
https://www.livescience.com/64203-ancient-hominins-saudi-arabia.html?utm_source=lsa-new...
"Ancient human relatives lived on the Arabian Peninsula for an astonishingly long time — from about 240,000 to 190,000 years ago — and spread into the heart of the region by following its blue rivers and lakes, a new study found.
"These early human relatives persisted for so long that they could have run into some modern humans, or Homo sapiens, along the way, the researchers said in the study,
***
"'Early hominins had small brains and made crude tools," Scerri told Live Science. "However, later hominins had bigger brains and were more sophisticated. Instead of crudely banging rocks together to produce sharp-edged stone flakes, they created beautiful, symmetrical artifacts called hand axes."
"Large, expertly shaped cutting tools (such as hand axes) made by hominins are known as Acheulean tools. These instruments — called the "the Swiss army knife of prehistory" — date to 1.5 million years ago; they come from the longest-lasting tool-making tradition in prehistory, Scerri said. Because it's rare to find hominin bones, Acheulean tools are a great stand-in for hominins when trying to figure out when and where they lived, the researchers said.
"It's unclear which hominins made the hand axes in Saudi Arabia. "However, hominins that have been found with Acheulean tools include Homo erectus, who was probably a direct ancestor of humans," Scerri said.
***
"The dating revealed that hominins lived in Saffaqah as recently as 188,000 years ago, making it the youngest Acheulean site in southwest Asia, the researchers found. This finding is remarkable, because it shows that the Arabian Acheulean ended just before or at the same time as the earliest H. sapiens made it to the region, the researchers said.
"The international team used luminescence dating to determine the age of the tools. This method measures how much light is emitted from energy stored in certain types of rock and soils, as certain minerals store energy from the sun at a known rate, Scerri said.
"When these minerals are buried, they can no longer store this energy," she said. "By heating the minerals, the stored energy becomes emptied, and the amount of energy that is emptied gives a measure of a point in time when that mineral was last exposed to daylight."
"The research also revealed that these hominins spread throughout Saudi Arabia's landscape via its blue waterways. Although Arabia is a vast desert today, it was greener during several brief periods in the past.
"'The hominins making the Acheulean tools at Saffaqah seemed to have made their way into the heart of Arabia when these now-dry river networks and channels were active," Scerri said.
"But Saudi Arabia was turning dry again by about 188,000 years ago, she said. So, it's likely that "the hominins responsible for these stone tools were quite resilient in the face of environmental challenges," she said. "Although the site of Saffaqah was not a desert when these Acheulean hominins were there, it was probably still quite an arid environment.'"
Comment: Disappearance of a hominin type is not like turning off a light bulb. They die off slowly. That H. sapiens and H. erectus lived side by side suggests sapiens appeared with no intermediate forms. H. sapiens by direct creation is possible.
Human evolution; savannah theory fading
by David Turell , Saturday, July 09, 2022, 19:25 (866 days ago) @ David Turell
More and more evidence of forest and jungle usage:
https://aeon.co/essays/we-are-creatures-of-tropical-jungles-as-much-as-the-savannah?utm...
"The earliest hominins, dating from around 7 to 5 million years ago, show that our ancestors’ first experiments with bipedalism occurred in mixed forest and woodland settings...Not only that, but analyses of fossil hominin skeletons dating between 5 to 2 million years ago, including that of ‘Lucy’ and those of our own genus, show that many of them still had arms, shoulders and hands adapted to climbing (a skill necessary for life in the forest) even as their interactions with terra firma increased.
***
"Researchers once assumed that bipedalism was driven by an expansion of grasslands. It was believed that, as those habitats spread, hominin physiology changed as it adapted to a new life on the open savannah. For this theory to hold water, these landscapes would have needed to expand roughly at the same time that physiological changes appear in hominin fossils. However, sediments from deep-sea marine cores show that ancient tropical African grasslands had already expanded by 10 million years ago, long before the first hominins took their first bipedal strides around 7 to 5 million years ago.
***
"Although open environments played a major role in early human evolution, tropical forests and forest patches still provided a significant backdrop for our first hominin ancestors as they emerged in the tropics of Africa. They likely took their first tentative steps as bipedal mammals in tropical forests, or at least mixed forest habitats. Right until the appearance of the genus Homo, between 3 to 2 million years ago, tropical forests and woodlands remained an important source of food, and perhaps offered protection from predators.
***
"There is growing evidence for the role of tropical forests in our species’ evolution and dispersal, and Batadomba-lena cave, where we started this essay, is a key site. This cave has rewritten tropical forests into European and North American accounts of human history. Over the course of the past two decades, tropical sites like Batadomba-lena (alongside nearby caves Fa-Hien Lena and Kitulgala Beli-lena) have produced some of the most important archaeological and anthropological insights into the evolution, behaviour and capabilities of early Homo sapiens. These caves in Sri Lanka have demonstrated that the first humans who arrived on this island did not head straight for the coasts or the open grasslands. Instead, the first human traces and fossils found here, dating back 45,000 years, come from dense tropical rainforests. Well-preserved fossils and artefacts in these cool cave environments have shown that humans hunted monkeys and giant squirrels with bow and arrow technology. They used carbohydrate-rich nuts and nearby freshwater streams. And they may even have made clothes to protect themselves – not from the cold, but from a myriad of vampiric pests.
***
"In 2021, amazing discoveries at a Sulawesi limestone cave called ‘Leang Bulu’ Sipong 4’ found that tropical forests are home to the oldest cave art ever recorded, dating to at least 45,500 years ago. These drawings show figures hunting wild pigs – animals known to enjoy forest habitats. Tropical forests were not just a key part of our species’ experimentation with different ecologies, but also cultural materials and perhaps also an important setting for the emergence of storytelling.
***
"Of course, other habitats are critical to the human story as well. There is now evidence that humans were making themselves at home in deserts, high mountains, and the Arctic circle by 45,000 years ago. Evidence found in tropical forests, as well as these other places, is encouraging archaeologists and anthropologists to move away from an exclusive focus on savannahs and coasts. They’re recognising that studying a plethora of Pleistocene climates and environments might provide the best clues to our origin story – and to what it means to be human.
***
"Thanks to the array of revolutionary findings discussed above, the ‘savannah hypothesis’ is becoming increasingly unattractive in palaeoanthropological and archaeological discourse. Instead, environments such as tropical forests are playing a critical role in highlighting that climatic and environmental variability provided the setting for the grand evolutionary romp of our species and its hominin ancestors.
***
"But it would be wrong to assume that palaeontologists and archaeologists are the only ones championing this new view of our diverse past. For centuries, if not millennia, Indigenous peoples have emphasised the long human history of tropical forests and the cultural heritage locked within them, though they have often been marginalised or ignored."
Comment: The idea that savannahs drove our evolution is shown as being much too simplistic. Not surprising as new research challenges old ideas. The evidence in this article shows we evolved to take advantage of new environments not as the result of new environments.
Human evolution; savannah theory fading
Savannah theory fading
DAVID: The idea that savannahs drove our evolution is shown as being much too simplistic. Not surprising as new research challenges old ideas.
Thank you for this fascinating article. I wonder what new research in say a thousand years' time might challenge old ideas about mysteries such as the Cambrian. Who knows? Meanwhile, however, I must say, I AM surprised by this discovery, but it all makes perfect sense.
QUOTE: Although open environments played a major role in early human evolution, tropical forests and forest patches still provided a significant backdrop for our first hominin ancestors as they emerged in the tropics of Africa. They likely took their first tentative steps as bipedal mammals in tropical forests, or at least mixed forest habitats[.
The first sentence is crucial. The implication seems to be that our intelligent ancestors learned to take full advantage of whatever conditions they found themselves in. They were therefore not forced into change by the loss of their original forest habitat, but instead exploited BOTH environments.
DAVID: The evidence in this article shows we evolved to take advantage of new environments not as the result of new environments.
Sorry, but I don’t see any difference. New environments require new skills, so we could hardly develop the new skills until the new environments were there. The implication is that like all other cell communities that speciated, ours had the (perhaps God-given) intelligence and the plasticity to TAKE ADVANTAGE of new conditions (in my posts I often use the word “exploit”) in order to innovate and not just to adapt. However, the article doesn’t talk expressly of new environments. The last sentence of the quote leaves it open: the forests were definitely still there, but if open environments played a “major role”, then we certainly can’t discount “mixed” habitats.
Human evolution; savannah theory fading
by David Turell , Sunday, July 10, 2022, 16:21 (865 days ago) @ dhw
Savannah theory fading
DAVID: The idea that savannahs drove our evolution is shown as being much too simplistic. Not surprising as new research challenges old ideas.
dhw: Thank you for this fascinating article. I wonder what new research in say a thousand years' time might challenge old ideas about mysteries such as the Cambrian. Who knows? Meanwhile, however, I must say, I AM surprised by this discovery, but it all makes perfect sense.
Why surprised? Rethinking Darwin theories today is common.
QUOTE: Although open environments played a major role in early human evolution, tropical forests and forest patches still provided a significant backdrop for our first hominin ancestors as they emerged in the tropics of Africa. They likely took their first tentative steps as bipedal mammals in tropical forests, or at least mixed forest habitats[.dhw: The first sentence is crucial. The implication seems to be that our intelligent ancestors learned to take full advantage of whatever conditions they found themselves in. They were therefore not forced into change by the loss of their original forest habitat, but instead exploited BOTH environments.
DAVID: The evidence in this article shows we evolved to take advantage of new environments not as the result of new environments.
dhw: Sorry, but I don’t see any difference. New environments require new skills, so we could hardly develop the new skills until the new environments were there. The implication is that like all other cell communities that speciated, ours had the (perhaps God-given) intelligence and the plasticity to TAKE ADVANTAGE of new conditions (in my posts I often use the word “exploit”) in order to innovate and not just to adapt. However, the article doesn’t talk expressly of new environments. The last sentence of the quote leaves it open: the forests were definitely still there, but if open environments played a “major role”, then we certainly can’t discount “mixed” habitats.
The point still is, and you haven't changed it, we evolved to use all sorts of environments in a warm jungle area (AFRICA) and then migrated all over to every climate on the Earth to easily adapt. The jungle origin did not provide that degree of adaptability for future use. The new big brain did just that and appeared in advance of migrations as the article shows.
Human evolution; savannah theory fading
QUOTE: Although open environments played a major role in early human evolution, tropical forests and forest patches still provided a significant backdrop for our first hominin ancestors as they emerged in the tropics of Africa. They likely took their first tentative steps as bipedal mammals in tropical forests, or at least mixed forest habitats
dhw: The first sentence is crucial. The implication seems to be that our intelligent ancestors learned to take full advantage of whatever conditions they found themselves in. They were therefore not forced into change by the loss of their original forest habitat, but instead exploited BOTH environments.
DAVID: The evidence in this article shows we evolved to take advantage of new environments not as the result of new environments.
dhw: Sorry, but I don’t see any difference. New environments require new skills, so we could hardly develop the new skills until the new environments were there. The implication is that like all other cell communities that speciated, ours had the (perhaps God-given) intelligence and the plasticity to TAKE ADVANTAGE of new conditions (in my posts I often use the word “exploit”) in order to innovate and not just to adapt. However, the article doesn’t talk expressly of new environments. The last sentence of the quote leaves it open: the forests were definitely still there, but if open environments played a “major role”, then we certainly can’t discount “mixed” habitats.
DAVID: The point still is, and you haven't changed it, we evolved to use all sorts of environments in a warm jungle area (AFRICA) and then migrated all over to every climate on the Earth to easily adapt. The jungle origin did not provide that degree of adaptability for future use. The new big brain did just that and appeared in advance of migrations as the article shows.
The “point” of the article actually shifts from the origin of bipedalism to much wider considerations, and you have chosen to focus on the brain, but the sentence I have bolded moves in the same direction. The brain - which incidentally is a community of cell communities - had the (perhaps God-given) ABILITY to adapt and innovate, and it used this ABILITY to cope with and exploit new environments. Why do you say the “new big brain”? The early ancestors “dating from around 7 to 5 million years ago” had tiny brains compared to ours! We know that the brain responds to new requirements by complexifying, and so each exploitation/innovation (possibly triggered by migration to new environments), would have increased the brain’s complexity and in due course created the need for greater capacity. We needn’t go into the subject of expansion here, as we have dealt with it repeatedly elsewhere, but quite clearly our earliest ancestors’ brains can only have evolved into new bigger brains AFTER (and I would say as a result of) “their first tentative steps as bipedal mammals in tropical forests, or at least mixed forest habitats”.
Human evolution; savannah theory fading
by David Turell , Monday, July 11, 2022, 17:23 (864 days ago) @ dhw
QUOTE: Although open environments played a major role in early human evolution, tropical forests and forest patches still provided a significant backdrop for our first hominin ancestors as they emerged in the tropics of Africa. They likely took their first tentative steps as bipedal mammals in tropical forests, or at least mixed forest habitats
dhw: The first sentence is crucial. The implication seems to be that our intelligent ancestors learned to take full advantage of whatever conditions they found themselves in. They were therefore not forced into change by the loss of their original forest habitat, but instead exploited BOTH environments.
DAVID: The evidence in this article shows we evolved to take advantage of new environments not as the result of new environments.
dhw: Sorry, but I don’t see any difference. New environments require new skills, so we could hardly develop the new skills until the new environments were there. The implication is that like all other cell communities that speciated, ours had the (perhaps God-given) intelligence and the plasticity to TAKE ADVANTAGE of new conditions (in my posts I often use the word “exploit”) in order to innovate and not just to adapt. However, the article doesn’t talk expressly of new environments. The last sentence of the quote leaves it open: the forests were definitely still there, but if open environments played a “major role”, then we certainly can’t discount “mixed” habitats.
DAVID: The point still is, and you haven't changed it, we evolved to use all sorts of environments in a warm jungle area (AFRICA) and then migrated all over to every climate on the Earth to easily adapt. The jungle origin did not provide that degree of adaptability for future use. The new big brain did just that and appeared in advance of migrations as the article shows.
dhw: The “point” of the article actually shifts from the origin of bipedalism to much wider considerations, and you have chosen to focus on the brain, but the sentence I have bolded moves in the same direction. The brain - which incidentally is a community of cell communities - had the (perhaps God-given) ABILITY to adapt and innovate, and it used this ABILITY to cope with and exploit new environments. Why do you say the “new big brain”? The early ancestors “dating from around 7 to 5 million years ago” had tiny brains compared to ours! We know that the brain responds to new requirements by complexifying, and so each exploitation/innovation (possibly triggered by migration to new environments), would have increased the brain’s complexity and in due course created the need for greater capacity. We needn’t go into the subject of expansion here, as we have dealt with it repeatedly elsewhere, but quite clearly our earliest ancestors’ brains can only have evolved into new bigger brains AFTER (and I would say as a result of) “their first tentative steps as bipedal mammals in tropical forests, or at least mixed forest habitats”.
The erectus brain developed in Africa and the erectus wandered all over the Earth handling new environments with ease. You can talk all around that without changing the import of that history. The brain came before all the required uses in subsequent migrations.
Human evolution; savannah theory fading
DAVID: The point still is, and you haven't changed it, we evolved to use all sorts of environments in a warm jungle area (AFRICA) and then migrated all over to every climate on the Earth to easily adapt. The jungle origin did not provide that degree of adaptability for future use. The new big brain did just that and appeared in advance of migrations as the article shows.
dhw: The “point” of the article actually shifts from the origin of bipedalism to much wider considerations, and you have chosen to focus on the brain, but the sentence I have bolded moves in the same direction. The brain - which incidentally is a community of cell communities - had the (perhaps God-given) ABILITY to adapt and innovate, and it used this ABILITY to cope with and exploit new environments. Why do you say the “new big brain”? The early ancestors “dating from around 7 to 5 million years ago” had tiny brains compared to ours! We know that the brain responds to new requirements by complexifying, and so each exploitation/innovation (possibly triggered by migration to new environments), would have increased the brain’s complexity and in due course created the need for greater capacity. We needn’t go into the subject of expansion here, as we have dealt with it repeatedly elsewhere, but quite clearly our earliest ancestors’ brains can only have evolved into new bigger brains AFTER (and I would say as a result of) “their first tentative steps as bipedal mammals in tropical forests, or at least mixed forest habitats”.
DAVID: The erectus brain developed in Africa and the erectus wandered all over the Earth handling new environments with ease. You can talk all around that without changing the import of that history. The brain came before all the required uses in subsequent migrations.
Why have you suddenly skipped millions of years and hominins and homos? The subject is human evolution. Our history reaches back millions of years to small-brained hominins who apparently still lived in forests, although it is possible that their environment was mixed. Lucy’s brain capacity was about 400 cc. What you call the “new big brain” was the result of expansion over millions of years as hominins and homos encountered new conditions and environments. We know the brain RESPONDS to new requirements. When you say: “The brain came before all the required uses”, yes, the little brain was there from the start, and it gradually became bigger as it learned to cope with or exploit new conditions, but Lucy was not born with the “new big brain”! Even erectus wasn’t born with the “new big brain”, since his/her brain appears to have expanded from approx. 850 cc to 1000 + cc. I’d hoped to avoid a repetition of our discussion on brain expansion, but you still seem to be hooked on the notion that every expansion was a divine dabble IN ANTICIPATION of new requirements.
Human evolution; savannah theory fading
by David Turell , Wednesday, July 13, 2022, 18:02 (862 days ago) @ dhw
DAVID: The erectus brain developed in Africa and the erectus wandered all over the Earth handling new environments with ease. You can talk all around that without changing the import of that history. The brain came before all the required uses in subsequent migrations.
dhw: Why have you suddenly skipped millions of years and hominins and homos? The subject is human evolution. Our history reaches back millions of years to small-brained hominins who apparently still lived in forests, although it is possible that their environment was mixed. Lucy’s brain capacity was about 400 cc. What you call the “new big brain” was the result of expansion over millions of years as hominins and homos encountered new conditions and environments. We know the brain RESPONDS to new requirements. When you say: “The brain came before all the required uses”, yes, the little brain was there from the start, and it gradually became bigger as it learned to cope with or exploit new conditions, but Lucy was not born with the “new big brain”! Even erectus wasn’t born with the “new big brain”, since his/her brain appears to have expanded from approx. 850 cc to 1000 + cc. I’d hoped to avoid a repetition of our discussion on brain expansion, but you still seem to be hooked on the notion that every expansion was a divine dabble IN ANTICIPATION of new requirements.
I agree the Erectus brain increased over time, but a key thrust of the article is Erectus
migration from Africa all over the world, as I stated above and from the article:
"The Pleistocene, which began about 2.58 million years ago and ended around 12,000 years ago, saw hominin horizons extend beyond Africa. From 1.8 million years ago, stone tools turn up in the cool climes of Dmanisi in Georgia and later in wet and windy Norfolk in the United Kingdom. Finds of crafted ‘Acheulean’ hand-axes act as ‘breadcrumbs’ for the extension of our genus from Africa into South Asia, the Middle East and Europe between 1.7 and 1 million years ago. Homo erectus was a key hominin player in this expansion. This hominin emerged in Africa around 2 million years ago and, as the name suggests, specialised in walking upright. Discoveries of stone tools and butchered animal carcasses suggest it also focused on hunting and scavenging meat from animals, including elephants and antelope, and preferred open grassland environments.
"With this meaty menu in mind, the first expansions of our ancestors beyond Africa have often been associated with periods of climate change that would have resulted in the extension of grassland ‘corridors’ out of Africa. Extending across the Middle East, Europe and Asia, these habitats supposedly provided open conveyor belts for the large animals that had become important sources of food for hominins. According to this theory, our ancestors followed their prey out of the continent. But what happened when these early hominin navigators reached tropical forest realms beyond Africa? We know that Homo erectus had made it to Java in Indonesia 1.5 million years ago. Was it met by a wall of dense tropical rainforest, or did it benefit from the penetration of grassland corridors down towards the equator?"
The brain came first and the migration afterward and did enlarge within the same species as new experiences occurred. Note! In contrast to our brain shrinking with new complex advanced uses. Why? I view us as a completed endpoint while Erectus was a work in progress as God designed it.
Human evolution; savannah theory fading
DAVID: The erectus brain developed in Africa and the erectus wandered all over the Earth handling new environments with ease. You can talk all around that without changing the import of that history. The brain came before all the required uses in subsequent migrations.
dhw: Why have you suddenly skipped millions of years and hominins and homos? The subject is human evolution. Our history reaches back millions of years to small-brained hominins who apparently still lived in forests, although it is possible that their environment was mixed. Lucy’s brain capacity was about 400 cc. What you call the “new big brain” was the result of expansion over millions of years as hominins and homos encountered new conditions and environments. We know the brain RESPONDS to new requirements. When you say: “The brain came before all the required uses”, yes, the little brain was there from the start, and it gradually became bigger as it learned to cope with or exploit new conditions, but Lucy was not born with the “new big brain”! Even erectus wasn’t born with the “new big brain”, since his/her brain appears to have expanded from approx. 850 cc to 1000 + cc. I’d hoped to avoid a repetition of our discussion on brain expansion, but you still seem to be hooked on the notion that every expansion was a divine dabble IN ANTICIPATION of new requirements.
DAVID: I agree the Erectus brain increased over time, but a key thrust of the article is Erectus migration from Africa all over the world, as I stated above and from the article:
I can only comment on the material you present to us. However, the extra material about erectus makes no difference to the argument. He was already “upright”, and “the first expansions of our ancestors beyond Africa have often been associated with periods of climate change that would have resulted in the extension of grassland ‘corridors’ out of Africa.” This clearly suggests that changes in living conditions coincided with changes in behaviour, and you have inadvertently explained the process of brain expansion in your comment:
DAVID: The brain came first and the migration afterward and did enlarge within the same
species as new experiences occurred.
The brain expands when it has to cope with new experiences that exceed its existing capacity. From the time when our earliest ancestors descended from the trees, there was a continuous expansion in response to new experiences. Yes, erectus came long after those earlier times and expansions, so when he migrated, he already had a bigger brain than his own ancestors, and then new experiences resulted in his own brain expansion. Thank you for confirming the sequence of the process: new experiences result in expansion.
DAVID: Note! In contrast to our brain shrinking with new complex advanced uses. Why? I view us as a completed endpoint while Erectus was a work in progress as God designed it.
This is what I wanted to avoid. We have been over it again and again. Why would your God have given us a brain bigger than was needed? A miscalculation? I propose that our brain had reached a point beyond which further expansion might have caused problems in the rest of the anatomy, and so the process of complexification (which had always existed) took over completely, and proved so efficient that some existing cells were no longer necessary. Hence shrinkage.
Human evolution; savannah theory fading
by David Turell , Thursday, July 14, 2022, 17:54 (861 days ago) @ dhw
DAVID: I agree the Erectus brain increased over time, but a key thrust of the article is Erectus migration from Africa all over the world, as I stated above and from the article:
dhw: I can only comment on the material you present to us. However, the extra material about erectus makes no difference to the argument. He was already “upright”, and “the first expansions of our ancestors beyond Africa have often been associated with periods of climate change that would have resulted in the extension of grassland ‘corridors’ out of Africa.” This clearly suggests that changes in living conditions coincided with changes in behaviour,
I'm sorry I confused you. I suggest you digest the entire article to follow my points. It makes clear an Erectus brain developed in Africa allowed them to migrate and adapt easily everywhere else. Clearly brain first.
DAVID: The brain came first and the migration afterward and did enlarge within the same
species as new experiences occurred.dhw: The brain expands when it has to cope with new experiences that exceed its existing capacity. From the time when our earliest ancestors descended from the trees, there was a continuous expansion in response to new experiences. Yes, erectus came long after those earlier times and expansions, so when he migrated, he already had a bigger brain than his own ancestors, and then new experiences resulted in his own brain expansion. Thank you for confirming the sequence of the process: new experiences result in expansion.
You and I have no factual evidence about what caused brains to enlarge. I follow the reasoning God designed each explansion.
DAVID: Note! In contrast to our brain shrinking with new complex advanced uses. Why? I view us as a completed endpoint while Erectus was a work in progress as God designed it.dhw: This is what I wanted to avoid. We have been over it again and again. Why would your God have given us a brain bigger than was needed? A miscalculation? I propose that our brain had reached a point beyond which further expansion might have caused problems in the rest of the anatomy, and so the process of complexification (which had always existed) took over completely, and proved so efficient that some existing cells were no longer necessary. Hence shrinkage.
And my more logical view of God is our oversized brain allowed for more efficient plasticity in handling the many new uses of complexity we had for our brain. As the brain reorganized in complexification it discarded unnecessary portions. God never miscalculates, and y our comment shows how you view God in a noxious disparaging way.
Human evolution; new older time line for humans
by David Turell , Thursday, July 14, 2022, 21:32 (861 days ago) @ David Turell
At the Sterkfontein caves in South Africa:
https://bigthink.com/the-past/human-evolution-challenged-older-fossils/?utm_source=mail...
"In 1936, South African doctor and paleontologist Robert Broom made a historic discovery in the Sterkfontein caves in South Africa. Broom discovered the first adult specimen of the genus Australopithecus, a group of early hominins from which our own genus, Homo, emerged.
"Since 1936, the Sterkfontein caves have become ground zero for Australopithecus research and fossil finds. The complex cave system runs 60 meters deep, and it has revealed hundreds of Australopithecus fossils within its sediment. From these rocks emerged notable discoveries, such as the nearly complete skeletons of specimens dubbed “Little Foot” and “Mrs. Ples.”
***
"The complex cave system still houses many secrets, but the discoveries already made retain mysteries of their own. Among the most debated issues is the age of the fossils found in Member 4. Researchers have estimated the age of Australopithecus in the lower Member 2 section at 3.7 million years, which jars with the estimated age of the fossils found higher in the cave. Researchers originally estimated the fossils in Member 4 to be between 2 million and 2.4 million years old. The geological peculiarities of the cave challenge traditional methods of aging fossils, casting further doubt on the accuracy of these estimations.
***
"Recently, Granger and a team of scientists from France and South Africa endeavored to redate the famous fossils using a new method. They published their results in the Proceedings of the National Academy of Sciences.
"The team discovered that scientists were right to doubt the original findings. The Australopithecus fossils in the Member 4 cave sediments date from 3.4 million to 3.7 million years ago, making them about a million years older than initially thought. With the famous fossils finally placed in the correct timeline, scientists can better picture the lives of these early hominins, including the environmental conditions in which they lived. The findings also increase the geographic range and diversity of our earliest ancestors, reigniting debates surrounding the story and timeline of human evolution.
***
"Combining their isotope results with an extensive geological survey of the area, the researchers concluded that the fossils are between 3.4 million and 3.7 million years old — at least a million years older than the original estimate of 2 million to 2.4 million years. This estimate makes the Member 4 Australopithecus the wise elders of the most well-known Australopithecus, “Dinkinesh” (also known as “Lucy”), which experts date as 3.2 million years old. The results also are consistent with the ages of the older specimens found in the lower reaches of the cave. With the discrepancy corrected, we now know that the entire Australopithecus assemblage at the South African site dates to between 3.4 million and 3.7 million years old.
***
"These findings challenge East Africa’s recognition as the first location humans evolved. South Africa is suddenly a contender for the most likely area of early human evolution — genuinely living up to the moniker Cradle of Humanity."
Comment: this seems like a more reasonable timeline for our development. But in contrast to whales our evolution is like a speedboat. They look fifteen million years or more:
https://en.wikipedia.org/wiki/Evolution_of_cetaceans
"The evolution of cetaceans is thought to have begun in the Indian subcontinent from even-toed ungulates 50 million years ago (mya) and to have proceeded over a period of at least 15 million years."
Human evolution; savannah theory fading
DAVID: I agree the Erectus brain increased over time, but a key thrust of the article is Erectus migration from Africa all over the world, as I stated above and from the article:
dhw: I can only comment on the material you present to us. However, the extra material about erectus makes no difference to the argument. He was already “upright”, and “the first expansions of our ancestors beyond Africa have often been associated with periods of climate change that would have resulted in the extension of grassland ‘corridors’ out of Africa.” This clearly suggests that changes in living conditions coincided with changes in behaviour.
DAVID: I'm sorry I confused you. I suggest you digest the entire article to follow my points. It makes clear an Erectus brain developed in Africa allowed them to migrate and adapt easily everywhere else. Clearly brain first.
You persist in starting in the middle of an ongoing process. The ability to adapt has been present since the first ancestors! Each expansion is the result of a new adaptation/innovation. Erectus’s brain started at, say, 850 cc, and – as you yourself have pointed out –it enlarged “as new experiences occurred”. That same process would have led earlier to the 850 cc with which erectus began. Once more: I propose that new experiences CAUSE enlargement, and the brain does not enlarge in anticipation of new conditions it has not yet encountered!
DAVID: You and I have no factual evidence about what caused brains to enlarge. I follow the reasoning God designed each expansion.
And since your God apparently only wanted to design sapiens and his brain, this is part of the theory that “makes sense only to God”. But you call it “reasoning”.
dhw: Why would your God have given us a brain bigger than was needed? A miscalculation? I propose that our brain had reached a point beyond which further expansion might have caused problems in the rest of the anatomy, and so the process of complexification (which had always existed) took over completely, and proved so efficient that some existing cells were no longer necessary. Hence shrinkage.
DAVID: And my more logical view of God is our oversized brain allowed for more efficient plasticity in handling the many new uses of complexity we had for our brain. As the brain reorganized in complexification it discarded unnecessary portions.
Thank you for repeating my own theory. I have no objection to the theory that if God exists, he would have designed the plasticity of cells, without which evolution – including that of the brain – would not have been possible. I only object to your theory that brain changes and all other evolutionary changes took place in anticipation of conditions/requirements that did not yet exist.
DAVID: God never miscalculates, and your comment shows how you view God in a noxious disparaging way.
I do not believe that God would have given us a brain bigger than we needed! But that was the disparaging implication of your insistence that he initially gave us an “oversized” brain. My version is that the brain initially expanded because the new cells were needed to meet new requirements. It was not “oversized”, and cells only became redundant because of the increased efficiency of complexification. There is absolutely nothing noxious or disparaging about God in any of my theories. But I admit to being disparaging about theories which suggest that your God had only one purpose and therefore deviated from his purpose in order to achieve it. I am also disparaging about your theory that evolutionary changes take place in anticipation of requirements that do not yet exist. It seems to me to be pure common sense that such changes would take place IN RESPONSE to new conditions/requirements, and not before these came into existence.
Human evolution; savannah theory fading
by David Turell , Friday, July 15, 2022, 15:56 (860 days ago) @ dhw
DAVID: I'm sorry I confused you. I suggest you digest the entire article to follow my points. It makes clear an Erectus brain developed in Africa allowed them to migrate and adapt easily everywhere else. Clearly brain first.
dhw: You persist in starting in the middle of an ongoing process. The ability to adapt has been present since the first ancestors! Each expansion is the result of a new adaptation/innovation. Erectus’s brain started at, say, 850 cc, and – as you yourself have pointed out –it enlarged “as new experiences occurred”. That same process would have led earlier to the 850 cc with which erectus began. Once more: I propose that new experiences CAUSE enlargement, and the brain does not enlarge in anticipation of new conditions it has not yet encountered!
Erectus with an 850cc brain appeared in Africa first. It was that brain's thinking capacity which allowed/stimulated Erectus to migrate all over the Earth. Brain first, actions followed! Nothing could be clearer.
DAVID: You and I have no factual evidence about what caused brains to enlarge. I follow the reasoning God designed each expansion.dhw: And since your God apparently only wanted to design sapiens and his brain, this is part of the theory that “makes sense only to God”. But you call it “reasoning”.
We both offer reasons about God, but it seems only yours are allowed to be reasonable.
dhw: Why would your God have given us a brain bigger than was needed? A miscalculation? I propose that our brain had reached a point beyond which further expansion might have caused problems in the rest of the anatomy, and so the process of complexification (which had always existed) took over completely, and proved so efficient that some existing cells were no longer necessary. Hence shrinkage.DAVID: And my more logical view of God is our oversized brain allowed for more efficient plasticity in handling the many new uses of complexity we had for our brain. As the brain reorganized in complexification it discarded unnecessary portions.
dhw: Thank you for repeating my own theory. I have no objection to the theory that if God exists, he would have designed the plasticity of cells, without which evolution – including that of the brain – would not have been possible. I only object to your theory that brain changes and all other evolutionary changes took place in anticipation of conditions/requirements that did not yet exist.
What you do not understand is a proper designer designs for future use. All part of design theory.
DAVID: God never miscalculates, and your comment shows how you view God in a noxious disparaging way.dhw: I do not believe that God would have given us a brain bigger than we needed! But that was the disparaging implication of your insistence that he initially gave us an “oversized” brain. My version is that the brain initially expanded because the new cells were needed to meet new requirements. It was not “oversized”, and cells only became redundant because of the increased efficiency of complexification. There is absolutely nothing noxious or disparaging about God in any of my theories. But I admit to being disparaging about theories which suggest that your God had only one purpose and therefore deviated from his purpose in order to achieve it. I am also disparaging about your theory that evolutionary changes take place in anticipation of requirements that do not yet exist. It seems to me to be pure common sense that such changes would take place IN RESPONSE to new conditions/requirements, and not before these came into existence.
I can only repeat the point above. A proper designer designs for future anticipated use, and a God-designer understands the future. And I would note, your comment about brain size does not answer the issue that our brain shrunk with use, therefor it obviously was oversized at the start. You have no understanding that God never deviates from His purposes. You just are confused as you try to outguess God's reasoning. See the other entry about staged evolution and how a designer works with it.
Human evolution; savannah theory fading
DAVID: [The article] makes clear an Erectus brain developed in Africa allowed them to migrate and adapt easily everywhere else. Clearly brain first.
dhw: You persist in starting in the middle of an ongoing process. The ability to adapt has been present since the first ancestors! Each expansion is the result of a new adaptation/innovation. Erectus’s brain started at, say, 850 cc, and – as you yourself have pointed out – it enlarged “as new experiences occurred”. That same process would have led earlier to the 850 cc with which erectus began. Once more: I propose that new experiences CAUSE enlargement, and the brain does not enlarge in anticipation of new conditions it has not yet encountered!
DAVID: Erectus with an 850cc brain appeared in Africa first. It was that brain's thinking capacity which allowed/stimulated Erectus to migrate all over the Earth. Brain first, actions followed! Nothing could be clearer.
But how did erectus get his 850 cc brain in the first place? You have pointed out that during his migrations his brain enlarged “as new experiences occurred”. If homo habilis was erectus’s immediate ancestor, and his brain capacity expanded from 650 to 800 cc., you can see a progression “as new experiences occurred”, and the expansion to erectus’s initial 850cc would have followed the same procedure. And when he migrated, there were more new experiences resulting in more expansions. New experiences/requirements first, then expansion as a result.
DAVID: You and I have no factual evidence about what caused brains to enlarge. I follow the reasoning God designed each expansion.
dhw: And since your God apparently only wanted to design sapiens and his brain, this is part of the theory that “makes sense only to God”. But you call it “reasoning”.
DAVID: We both offer reasons about God, but it seems only yours are allowed to be reasonable.
It’s not a question of being “allowed”. You can’t find any logic in your theories, which make sense only to God, i.e. not to you. What logical flaws have you found in my theories?
dhw: Why would your God have given us a brain bigger than was needed? A miscalculation? I propose that our brain had reached a point beyond which further expansion might have caused problems in the rest of the anatomy, and so the process of complexification (which had always existed) took over completely, and proved so efficient that some existing cells were no longer necessary. Hence shrinkage.
DAVID: And my more logical view of God is our oversized brain allowed for more efficient plasticity in handling the many new uses of complexity we had for our brain. bbbAs the brain reorganized in complexification it discarded unnecessary portions.
dhw: Thank you for repeating my own theory. I have no objection to the theory that if God exists, he would have designed the plasticity of cells, without which evolution – including that of the brain – would not have been possible. I only object to your theory that brain changes and all other evolutionary changes took place in anticipation of conditions/requirements that did not yet exist.
DAVID: What you do not understand is a proper designer designs for future use. All part of design theory.
I am not denying that once the designs had proved successful, they would then be used in the future. But for example, I do not believe pre-whale legs were turned into flippers before the animals began to explore life in the water. And I would propose that the invention of the spear would have required major new skills and hence major changes to the brain, rather than the brain changing in anticipation of the making and use of the spear.
DAVID: God never miscalculates, and your comment shows how you view God in a noxious disparaging way.
dhw: I do not believe that God would have given us a brain bigger than we needed! But that was the disparaging implication of your insistence that he initially gave us an “oversized” brain. […]
DAVID […] And I would note, your comment about brain size does not answer the issue that our brain shrunk with use, therefor it obviously was oversized at the start.
In my theory, it would not have been oversized at the start. That would indeed have made it a miscalculation if your God did it! The cells that resulted in expansion would have been needed to meet some new requirement. But later, as further expansion might have caused problems, complexification took over almost completely, and it was so efficient that some cells which had been needed earlier then became redundant.
DAVID: You have no understanding that God never deviates from His purposes. You just are confused as you try to outguess God's reasoning. See the other entry about staged evolution and how a designer works with it.
I remain flummoxed by your insistence that he had only one purpose (to design sapiens plus food), and proceeded to design countless forms and foods that had no connection with sapiens but these were not deviations. I don’t know how this is meant to prove that your God dabbled with brains and bodies before changes were required, but I do sometimes have difficulty following your train of thought!
Human evolution; savannah theory fading
by David Turell , Saturday, July 16, 2022, 14:40 (859 days ago) @ dhw
DAVID: Erectus with an 850cc brain appeared in Africa first. It was that brain's thinking capacity which allowed/stimulated Erectus to migrate all over the Earth. Brain first, actions followed! Nothing could be clearer.
dhw: But how did erectus get his 850 cc brain in the first place? You have pointed out that during his migrations his brain enlarged “as new experiences occurred”. If homo habilis was erectus’s immediate ancestor, and his brain capacity expanded from 650 to 800 cc., you can see a progression “as new experiences occurred”, and the expansion to erectus’s initial 850cc would have followed the same procedure. And when he migrated, there were more new experiences resulting in more expansions. New experiences/requirements first, then expansion as a result.
We are not discussing how Erectus got his first brain, but that his brain allowed him to navigate the entire Earth, with brain coming before the future events for which the brain prepared him.
DAVID: We both offer reasons about God, but it seems only yours are allowed to be reasonable.
dhw: It’s not a question of being “allowed”. You can’t find any logic in your theories, which make sense only to God, i.e. not to you. What logical flaws have you found in my theories?
Covered before: your humanized god is not acceptable to me.
dhw: Why would your God have given us a brain bigger than was needed? A miscalculation? I propose that our brain had reached a point beyond which further expansion might have caused problems in the rest of the anatomy, and so the process of complexification (which had always existed) took over completely, and proved so efficient that some existing cells were no longer necessary. Hence shrinkage.DAVID: And my more logical view of God is our oversized brain allowed for more efficient plasticity in handling the many new uses of complexity we had for our brain. bbbAs the brain reorganized in complexification it discarded unnecessary portions.
dhw: Thank you for repeating my own theory. I have no objection to the theory that if God exists, he would have designed the plasticity of cells, without which evolution – including that of the brain – would not have been possible. I only object to your theory that brain changes and all other evolutionary changes took place in anticipation of conditions/requirements that did not yet exist.
DAVID: What you do not understand is a proper designer designs for future use. All part of design theory.
dhw: I am not denying that once the designs had proved successful, they would then be used in the future. But for example, I do not believe pre-whale legs were turned into flippers before the animals began to explore life in the water. And I would propose that the invention of the spear would have required major new skills and hence major changes to the brain, rather than the brain changing in anticipation of the making and use of the spear.
I know your complaint about God designing for future use.
DAVID: God never miscalculates, and your comment shows how you view God in a noxious disparaging way.dhw: I do not believe that God would have given us a brain bigger than we needed! But that was the disparaging implication of your insistence that he initially gave us an “oversized” brain. […]
DAVID […] And I would note, your comment about brain size does not answer the issue that our brain shrunk with use, therefor it obviously was oversized at the start.
dhw: In my theory, it would not have been oversized at the start. That would indeed have made it a miscalculation if your God did it! The cells that resulted in expansion would have been needed to meet some new requirement. But later, as further expansion might have caused problems, complexification took over almost completely, and it was so efficient that some cells which had been needed earlier then became redundant.
Further expansion didn't happen, but shrinkage did. The obvious explanation is the extra
cells allowed humans to use the brain as they wished, not as God might have required.
DAVID: You have no understanding that God never deviates from His purposes. You just are confused as you try to outguess God's reasoning. See the other entry about staged evolution and how a designer works with it.dhw: I remain flummoxed by your insistence that he had only one purpose (to design sapiens plus food), and proceeded to design countless forms and foods that had no connection with sapiens but these were not deviations. I don’t know how this is meant to prove that your God dabbled with brains and bodies before changes were required, but I do sometimes have difficulty following your train of thought!
I know. You do not know now to think about God
Human evolution; savannah theory fading
DAVID: Erectus with an 850cc brain appeared in Africa first. It was that brain's thinking capacity which allowed/stimulated Erectus to migrate all over the Earth. Brain first, actions followed! Nothing could be clearer.
dhw: But how did erectus get his 850 cc brain in the first place? You have pointed out that during his migrations his brain enlarged “as new experiences occurred”. If homo habilis was erectus’s immediate ancestor, and his brain capacity expanded from 650 to 800 cc., you can see a progression “as new experiences occurred”, and the expansion to erectus’s initial 850cc would have followed the same procedure. And when he migrated, there were more new experiences resulting in more expansions. New experiences/requirements first, then expansion as a result.
DAVID: We are not discussing how Erectus got his first brain, but that his brain allowed him to navigate the entire Earth, with brain coming before the future events for which the brain prepared him.
We are discussing your theory that your God expanded brains in anticipation of future events, whereas my proposal is that brains expanded – as you have agreed in your interpretation of erectus’s expansion – “as new experiences occurred”, i.e. in response to new experiences and not in anticipation of them.
DAVID: What you do not understand is a proper designer designs for future use. All part of design theory.
dhw: I am not denying that once the designs had proved successful, they would then be used in the future. But for example, I do not believe pre-whale legs were turned into flippers before the animals began to explore life in the water. And I would propose that the invention of the spear would have required major new skills and hence major changes to the brain, rather than the brain changing in anticipation of the making and use of the spear.
DAVID: I know your complaint about God designing for future use.
So please tell me why you find my argument illogical.
DAVID […][…] your comment about brain size does not answer the issue that our brain shrunk with use, therefor it obviously was oversized at the start.
dhw: In my theory, it would not have been oversized at the start. That would indeed have made it a miscalculation if your God did it! The cells that resulted in expansion would have been needed to meet some new requirement. But later, as further expansion might have caused problems, complexification took over almost completely, and it was so efficient that some cells which had been needed earlier then became redundant.
DAVID: Further expansion didn't happen, but shrinkage did. The obvious explanation is the extra cells allowed humans to use the brain as they wished, not as God might have required.
This is the weirdest explanation yet: your God gave humans extra cells so that they could have free will, and then what happened? The cells disappeared? But we were left with free will? Please explain why you reject my explanation above.
DAVID: You have no understanding that God never deviates from His purposes. You just are confused as you try to outguess God's reasoning. See the other entry about staged evolution and how a designer works with it.
dhw: I remain flummoxed by your insistence that he had only one purpose (to design sapiens plus food), and proceeded to design countless forms and foods that had no connection with sapiens but these were not deviations. I don’t know how this is meant to prove that your God dabbled with brains and bodies before changes were required, but I do sometimes have difficulty following your train of thought!
DAVID: I know. You do not know How to think about God.
You are trying to teach me that the way to think about God is that none of his actions make any sense to us humans, whereas any alternative theories that do make sense to us (you agree that all my explanations are logical) are impossible because they endow God with human thought patterns, although you agree that God certainly/probably/ possibly has human thought patterns.
Human evolution; savannah theory fading
by David Turell , Sunday, July 17, 2022, 15:55 (858 days ago) @ dhw
DAVID: We are not discussing how Erectus got his first brain, but that his brain allowed him to navigate the entire Earth, with brain coming before the future events for which the brain prepared him.
dhw: We are discussing your theory that your God expanded brains in anticipation of future events, whereas my proposal is that brains expanded – as you have agreed in your interpretation of erectus’s expansion – “as new experiences occurred”, i.e. in response to new experiences and not in anticipation of them.
Your approach to evolution is to find any argument to avoid a designer God who plans organisms for their future events as below:
DAVID: What you do not understand is a proper designer designs for future use. All part of design theory.dhw: I am not denying that once the designs had proved successful, they would then be used in the future. But for example, I do not believe pre-whale legs were turned into flippers before the animals began to explore life in the water. And I would propose that the invention of the spear would have required major new skills and hence major changes to the brain, rather than the brain changing in anticipation of the making and use of the spear.
DAVID: I know your complaint about God designing for future use.
dhw: So please tell me why you find my argument illogical.
Because I find a designer God fits the facts much better than your contortions that use somehow creates evolution.
DAVID […][…] your comment about brain size does not answer the issue that our brain shrunk with use, therefor it obviously was oversized at the start.dhw: In my theory, it would not have been oversized at the start. That would indeed have made it a miscalculation if your God did it! The cells that resulted in expansion would have been needed to meet some new requirement. But later, as further expansion might have caused problems, complexification took over almost completely, and it was so efficient that some cells which had been needed earlier then became redundant.
DAVID: Further expansion didn't happen, but shrinkage did. The obvious explanation is the extra cells allowed humans to use the brain as they wished, not as God might have required.
dhw: This is the weirdest explanation yet: your God gave humans extra cells so that they could have free will, and then what happened? The cells disappeared. But we were left with free will? Please explain why you reject my explanation above.
Free will was built into our brains as given. So was the process of complexification which is part and parcel of how our brain was designed by God to use the extra cells. God did not plan a redundancy as a mistake, but a purposeful to allow us freedom to develop our uses of brain in our own way.
DAVID: You have no understanding that God never deviates from His purposes. You just are confused as you try to outguess God's reasoning. See the other entry about staged evolution and how a designer works with it.dhw: I remain flummoxed by your insistence that he had only one purpose (to design sapiens plus food), and proceeded to design countless forms and foods that had no connection with sapiens but these were not deviations. I don’t know how this is meant to prove that your God dabbled with brains and bodies before changes were required, but I do sometimes have difficulty following your train of thought!
DAVID: I know. You do not know How to think about God.
dhw: You are trying to teach me that the way to think about God is that none of his actions make any sense to us humans, whereas any alternative theories that do make sense to us (you agree that all my explanations are logical) are impossible because they endow God with human thought patterns, although you agree that God certainly/probably/ possibly has human thought patterns.
God is in no way human. You cannot reason as God does.
Human evolution; savannah theory fading
DAVID: We are not discussing how Erectus got his first brain, but that his brain allowed him to navigate the entire Earth, with brain coming before the future events for which the brain prepared him.
dhw: We are discussing your theory that your God expanded brains in anticipation of future events, whereas my proposal is that brains expanded – as you have agreed in your interpretation of erectus’s expansion – “as new experiences occurred”, i.e. in response to new experiences and not in anticipation of them.
DAVID: Your approach to evolution is to find any argument to avoid a designer God who plans organisms for their future events as below:
I’m challenging the argument that although we know organisms adapt IN RESPONSE to changing conditions, the innovations that resulted in speciation were put in place in order to meet future requirements that did not yet exist.
DAVID: What you do not understand is a proper designer designs for future use. All part of design theory.
dhw: I am not denying that once the designs had proved successful, they would then be used in the future. But for example, I do not believe pre-whale legs were turned into flippers before the animals began to explore life in the water. And I would propose that the invention of the spear would have required major new skills and hence major changes to the brain, rather than the brain changing in anticipation of the making and use of the spear.
DAVID: I know your complaint about God designing for future use.
dhw: So please tell me why you find my argument illogical.
DAVID: Because I find a designer God fits the facts much better than your contortions that use somehow creates evolution.
We’re not arguing about the existence of a designer God. I am an agnostic. I find it perfectly conceivable that if he exists, he would have created the autonomous mechanisms whereby organisms adapt in response to changing conditions. I propose that the same mechanisms would have created the innovations which resulted in speciation by exploiting new opportunities provided by changing conditions. I find this far more logical than the proposal that every innovation was the result of your God looking into his crystal ball, forecasting future changes in conditions, and popping in to perform operations that would provide innovations which could not be used until conditions changed.
DAVID […] your comment about brain size does not answer the issue that our brain shrunk with use, therefor it obviously was oversized at the start.
dhw: In my theory, it would not have been oversized at the start. That would indeed have made it a miscalculation if your God did it! The cells that resulted in expansion would have been needed to meet some new requirement. But later, as further expansion might have caused problems, complexification took over almost completely, and it was so efficient that some cells which had been needed earlier then became redundant.
DAVID: Further expansion didn't happen, but shrinkage did. The obvious explanation is the extra cells allowed humans to use the brain as they wished, not as God might have required.
dhw: This is the weirdest explanation yet: your God gave humans extra cells so that they could have free will, and then what happened? The cells disappeared. But we were left with free will? Please explain why you reject my explanation above.
DAVID: Free will was built into our brains as given. So was the process of complexification which is part and parcel of how our brain was designed by God to use the extra cells. God did not plan a redundancy as a mistake, but a purposeful to allow us freedom to develop our uses of brain in our own way.
I’m sorry, but I can’t follow this. Please explain why you think your God gave us extra cells which turned out to be redundant. Since you have ignored my explanation of shrinkage, let me repeat it: the extra cells were needed at the time to perform a new function, but as further expansion might have caused problems, complexification later took over and was so efficient that some existing cells were no longer needed. Please explain why you find this theory unacceptable.
DAVID: You do not know How to think about God.
dhw: You are trying to teach me that the way to think about God is that none of his actions make any sense to us humans, whereas any alternative theories that do make sense to us (you agree that all my explanations are logical) are impossible because they endow God with human thought patterns, although you agree that God certainly/probably/ possibly has human thought patterns.
DAVID: God is in no way human. You cannot reason as God does.
Nobody knows your God’s reasons (if he exists). We can only theorize. Your theories of evolution are so irrational that you tell us that they “make sense only to God”. That means they do not make sense to you. My alternative theories make perfect sense to both of us. Nobody knows your God’s nature (if he exists). We can only theorize. How, then, do you know that your God does NOT have the human attributes (e.g. the enjoyment and the interest which you yourself were once certain of) associated with my alternative theories?
Human evolution; savannah theory fading
by David Turell , Monday, July 18, 2022, 17:32 (857 days ago) @ dhw
DAVID: Your approach to evolution is to find any argument to avoid a designer God who plans organisms for their future events as below:
dhw: I’m challenging the argument that although we know organisms adapt IN RESPONSE to changing conditions, the innovations that resulted in speciation were put in place in order to meet future requirements that did not yet exist.
I know. Designers always design for future use.
dhw: So please tell me why you find my argument illogical.
DAVID: Because I find a designer God fits the facts much better than your contortions that use somehow creates evolution.
dhw: We’re not arguing about the existence of a designer God. I am an agnostic. I find it perfectly conceivable that if he exists, he would have created the autonomous mechanisms whereby organisms adapt in response to changing conditions. I propose that the same mechanisms would have created the innovations which resulted in speciation by exploiting new opportunities provided by changing conditions. I find this far more logical than the proposal that every innovation was the result of your God looking into his crystal ball, forecasting future changes in conditions, and popping in to perform operations that would provide innovations which could not be used until conditions changed.
All you are doing is supporting agnosticism which is your right. See the other thread to try to comprehend how I think about God in vast contrast to your method.
DAVID […] your comment about brain size does not answer the issue that our brain shrunk with use, therefor it obviously was oversized at the start.dhw: In my theory, it would not have been oversized at the start. That would indeed have made it a miscalculation if your God did it! The cells that resulted in expansion would have been needed to meet some new requirement. But later, as further expansion might have caused problems, complexification took over almost completely, and it was so efficient that some cells which had been needed earlier then became redundant.
DAVID: Further expansion didn't happen, but shrinkage did. The obvious explanation is the extra cells allowed humans to use the brain as they wished, not as God might have required.
dhw: This is the weirdest explanation yet: your God gave humans extra cells so that they could have free will, and then what happened? The cells disappeared. But we were left with free will? Please explain why you reject my explanation above.
DAVID: Free will was built into our brains as given. So was the process of complexification which is part and parcel of how our brain was designed by God to use the extra cells. God did not plan a redundancy as a mistake, but a purposeful to allow us freedom to develop our uses of brain in our own way.
dhw: I’m sorry, but I can’t follow this. Please explain why you think your God gave us extra cells which turned out to be redundant. Since you have ignored my explanation of shrinkage, let me repeat it: the extra cells were needed at the time to perform a new function, but as further expansion might have caused problems, complexification later took over and was so efficient that some existing cells were no longer needed. Please explain why you find this theory unacceptable.
Weird view: our sapiens brain came fully complete with extra neurons and the complexification plasticity ability from its beginning. Allows new humans to develop brain usage as they wished, a fully open-ended preparation for the future usage.
DAVID: You do not know How to think about God.dhw: You are trying to teach me that the way to think about God is that none of his actions make any sense to us humans, whereas any alternative theories that do make sense to us (you agree that all my explanations are logical) are impossible because they endow God with human thought patterns, although you agree that God certainly/probably/ possibly has human thought patterns.
DAVID: God is in no way human. You cannot reason as God does.
dhw: Nobody knows your God’s reasons (if he exists). We can only theorize. Your theories of evolution are so irrational that you tell us that they “make sense only to God”. That means they do not make sense to you. My alternative theories make perfect sense to both of us. Nobody knows your God’s nature (if he exists). We can only theorize. How, then, do you know that your God does NOT have the human attributes (e.g. the enjoyment and the interest which you yourself were once certain of) associated with my alternative theories?
No need to repeat: it is all in the other thread.
Human evolution; savannah theory fading
DAVID: Your approach to evolution is to find any argument to avoid a designer God who plans organisms for their future events as below:
dhw: I’m challenging the argument that although we know organisms adapt IN RESPONSE to changing conditions, the innovations that resulted in speciation were put in place in order to meet future requirements that did not yet exist.
DAVID: I know. Designers always design for future use.
For someone who tells us ad nauseam that God does not think like us, it’s amazing how you can pick on a form of design that no human has ever succeeded in emulating, and insist that since humans design in a certain way, God must do the same. I am haunted by the vision of your prewhales flapping their flippers on a vast stretch of dry land, waiting to find out what they were supposed to do with them. On the other hand, I have no problem accepting the theory that when our ancestors first thought of inventing a weapon which would kill their prey from a safe distance, the design, making and use of the spear would have required additional cells to those they already had, and of course these (and the spear) would then have been used in the future. In other words, it makes perfect sense to me that just as the brain complexifies in response to new requirements, in earlier times it would have expanded for the same reason.
dhw: So please tell me why you find my argument illogical.
DAVID: Because I find a designer God fits the facts much better than your contortions that use somehow creates evolution.
dhw: We’re not arguing about the existence of a designer God. I am an agnostic. I find it perfectly conceivable that if he exists, he would have created the autonomous mechanisms whereby organisms adapt in response to changing conditions. I propose that the same mechanisms would have created the innovations which resulted in speciation by exploiting new opportunities provided by changing conditions. I find this far more logical than the proposal that every innovation was the result of your God looking into his crystal ball, forecasting future changes in conditions, and popping in to perform operations that would provide innovations which could not be used until conditions changed.
DAVID: All you are doing is supporting agnosticism which is your right. See the other thread to try to comprehend how I think about God in vast contrast to your method.
My proposal has nothing whatsoever to do with my agnosticism, since it allows for the existence of your God as the designer of the mechanisms. The other thread presents us with a God who believes he should/has to create countless forms that have no connection with the only form he wants to create. And yet you often call the God of my logical alternative versions “weak” and “bumbling”!
dhw: Please explain why you think your God gave us extra cells which turned out to be redundant. Since you have ignored my explanation of shrinkage, let me repeat it: the extra cells were needed at the time to perform a new function, but as further expansion might have caused problems, complexification later took over and was so efficient that some existing cells were no longer needed. Please explain why you find this theory unacceptable.
DAVID: Weird view: our sapiens brain came fully complete with extra neurons and the complexification plasticity ability from its beginning. Allows new humans to develop brain usage as they wished, a fully open-ended preparation for the future usage.
I have no idea what you mean by “fully complete”, unless you are referring to my theory that it could not expand any more. It would certainly have had “extra neurons” if it had more neurons than the brains of its ancestors, and we have agreed that all stages of brain development had “complexification plasticity”. I also have no idea why you have pinpointed the new neurons as being those that gave us free will (as if all our ancestors were automatons), and you have not explained shrinkage, i.e. the disappearance of cells. In fact the “weird” implication of what you have written is that God gave us extra cells for free will, and then took them away again! So what happened to free will? Now would you please explain why you find my own theory unacceptable.
Human evolution; savannah theory fading
by David Turell , Tuesday, July 19, 2022, 20:40 (856 days ago) @ dhw
DAVID: Your approach to evolution is to find any argument to avoid a designer God who plans organisms for their future events as below:
dhw: I’m challenging the argument that although we know organisms adapt IN RESPONSE to changing conditions, the innovations that resulted in speciation were put in place in order to meet future requirements that did not yet exist.
DAVID: I know. Designers always design for future use.
dhw: For someone who tells us ad nauseam that God does not think like us, it’s amazing how you can pick on a form of design that no human has ever succeeded in emulating, and insist that since humans design in a certain way, God must do the same. I am haunted by the vision of your prewhales flapping their flippers on a vast stretch of dry land, waiting to find out what they were supposed to do with them. On the other hand, I have no problem accepting the theory that when our ancestors first thought of inventing a weapon which would kill their prey from a safe distance, the design, making and use of the spear would have required additional cells to those they already had, and of course these (and the spear) would then have been used in the future. In other words, it makes perfect sense to me that just as the brain complexifies in response to new requirements, in earlier times it would have expanded for the same reason.
I think our brain acts like those in the past. Habilis and erectus had plenty of neurons to think and plan with to allow for the built-in complexification to work. All by God's designs.
dhw: So please tell me why you find my argument illogical.DAVID: Because I find a designer God fits the facts much better than your contortions that use somehow creates evolution.
dhw: We’re not arguing about the existence of a designer God. I am an agnostic. I find it perfectly conceivable that if he exists, he would have created the autonomous mechanisms whereby organisms adapt in response to changing conditions. I propose that the same mechanisms would have created the innovations which resulted in speciation by exploiting new opportunities provided by changing conditions. I find this far more logical than the proposal that every innovation was the result of your God looking into his crystal ball, forecasting future changes in conditions, and popping in to perform operations that would provide innovations which could not be used until conditions changed.
DAVID: All you are doing is supporting agnosticism which is your right. See the other thread to try to comprehend how I think about God in vast contrast to your method.
dhw:n My proposal has nothing whatsoever to do with my agnosticism, since it allows for the existence of your God as the designer of the mechanisms. The other thread presents us with a God who believes he should/has to create countless forms that have no connection with the only form he wants to create. And yet you often call the God of my logical alternative versions “weak” and “bumbling”!
You seem incapable of realizing how human you envision God to be.
dhw: Please explain why you think your God gave us extra cells which turned out to be redundant. Since you have ignored my explanation of shrinkage, let me repeat it: the extra cells were needed at the time to perform a new function, but as further expansion might have caused problems, complexification later took over and was so efficient that some existing cells were no longer needed. Please explain why you find this theory unacceptable.DAVID: Weird view: our sapiens brain came fully complete with extra neurons and the complexification plasticity ability from its beginning. Allows new humans to develop brain usage as they wished, a fully open-ended preparation for the future usage.
dhw: I have no idea what you mean by “fully complete”, unless you are referring to my theory that it could not expand any more. It would certainly have had “extra neurons” if it had more neurons than the brains of its ancestors, and we have agreed that all stages of brain development had “complexification plasticity”. I also have no idea why you have pinpointed the new neurons as being those that gave us free will (as if all our ancestors were automatons), and you have not explained shrinkage, i.e. the disappearance of cells. In fact the “weird” implication of what you have written is that God gave us extra cells for free will, and then took them away again! So what happened to free will? Now would you please explain why you find my own theory unacceptable.
To explain again: We came with extra neurons in our brain so we could use our brain as we wished which gave us free will. The loss of superfluous neurons had nothing to do with losing free will with the remaining cells fully adequate to allow us to think freely.
Human evolution; savannah theory fading
DAVID: Your approach to evolution is to find any argument to avoid a designer God who plans organisms for their future events as below:
dhw: I’m challenging the argument that although we know organisms adapt IN RESPONSE to changing conditions, the innovations that resulted in speciation were put in place in order to meet future requirements that did not yet exist.
DAVID: I know. Designers always design for future use.
dhw: For someone who tells us ad nauseam that God does not think like us, it’s amazing how you can pick on a form of design that no human has ever succeeded in emulating, and insist that since humans design in a certain way, God must do the same. I am haunted by the vision of your prewhales flapping their flippers on a vast stretch of dry land, waiting to find out what they were supposed to do with them. On the other hand, I have no problem accepting the theory that when our ancestors first thought of inventing a weapon which would kill their prey from a safe distance, the design, making and use of the spear would have required additional cells to those they already had, and of course these (and the spear) would then have been used in the future. In other words, it makes perfect sense to me that just as the brain complexifies in response to new requirements, in earlier times it would have expanded for the same reason.
DAVID: I think our brain acts like those in the past. Habilis and erectus had plenty of neurons to think and plan with to allow for the built-in complexification to work. All by God's designs.
I agree that our brains act like those in the past, except that when their brains’ capacity for complexification proved inadequate for new requirements, they expanded, whereas in our case, the new requirements were dealt with by enhanced complexification. I’m delighted to see that in this response you have dropped the notion that your God kept operating on various life forms in order to provide flippers or additional brain cells BEFORE they were required. […]
DAVID: All you are doing is supporting agnosticism which is your right. See the other thread to try to comprehend how I think about God in vast contrast to your method.
dhw: My proposal has nothing whatsoever to do with my agnosticism, since it allows for the existence of your God as the designer of the mechanisms. The other thread presents us with a God who believes he should/has to create countless forms that have no connection with the only form he wants to create. And yet you often call the God of my logical alternative versions “weak” and “bumbling”!
DAVID: You seem incapable of realizing how human you envision God to be.
In each of my theories I propose a particular theistic approach to evolution in order to explain the facts: experimentation, learning and getting new ideas as he goes along, deliberately creating a free-for-all as being more interesting than a puppet show (though always with the option of dabbling). I don’t see these “human” approaches as being any more “human” than your own belief that God enjoys creating and is interested in his creations, or – as you have now told us – that he wants us to think about him, recognize him, and ask questions.
dhw: Please explain why you think your God gave us extra cells which turned out to be redundant. Since you have ignored my explanation of shrinkage, let me repeat it: the extra cells were needed at the time to perform a new function, but as further expansion might have caused problems, complexification later took over and was so efficient that some existing cells were no longer needed. Please explain why you find this theory unacceptable.
DAVID: To explain again: We came with extra neurons in our brain so we could use our brain as we wished which gave us free will. The loss of superfluous neurons had nothing to do with losing free will with the remaining cells fully adequate to allow us to think freely.
So your new theory is that our extra neurons gave us free will – i.e. all our ancestors were automatons! Why, then, did these additional cells make our brain “oversized”? Clearly these new cells would have been of crucial importance to us! Hardly an explanation of shrinkage, is it? And still you refuse to explain why you find my theory unacceptable.
Human evolution; savannah theory fading
by David Turell , Wednesday, July 20, 2022, 20:24 (855 days ago) @ dhw
DAVID: I think our brain acts like those in the past. Habilis and erectus had plenty of neurons to think and plan with to allow for the built-in complexification to work. All by God's designs.
dhw: I agree that our brains act like those in the past, except that when their brains’ capacity for complexification proved inadequate for new requirements, they expanded, whereas in our case, the new requirements were dealt with by enhanced complexification. I’m delighted to see that in this response you have dropped the notion that your God kept operating on various life forms in order to provide flippers or additional brain cells BEFORE they were required. […]
Didn't you note I noted 'all by God's designs'?
DAVID: All you are doing is supporting agnosticism which is your right. See the other thread to try to comprehend how I think about God in vast contrast to your method.dhw: My proposal has nothing whatsoever to do with my agnosticism, since it allows for the existence of your God as the designer of the mechanisms. The other thread presents us with a God who believes he should/has to create countless forms that have no connection with the only form he wants to create. And yet you often call the God of my logical alternative versions “weak” and “bumbling”!
DAVID: You seem incapable of realizing how human you envision God to be.
dhw: In each of my theories I propose a particular theistic approach to evolution in order to explain the facts: experimentation, learning and getting new ideas as he goes along, deliberately creating a free-for-all as being more interesting than a puppet show (though always with the option of dabbling). I don’t see these “human” approaches as being any more “human” than your own belief that God enjoys creating and is interested in his creations, or – as you have now told us – that he wants us to think about him, recognize him, and ask questions.
As explained in the other thread God's possible reactions to his creations are secondary events, never on purpose as a cause of creation.
dhw: Please explain why you think your God gave us extra cells which turned out to be redundant. Since you have ignored my explanation of shrinkage, let me repeat it: the extra cells were needed at the time to perform a new function, but as further expansion might have caused problems, complexification later took over and was so efficient that some existing cells were no longer needed. Please explain why you find this theory unacceptable.DAVID: To explain again: We came with extra neurons in our brain so we could use our brain as we wished which gave us free will. The loss of superfluous neurons had nothing to do with losing free will with the remaining cells fully adequate to allow us to think freely.
dhw: So your new theory is that our extra neurons gave us free will – i.e. all our ancestors were automatons! Why, then, did these additional cells make our brain “oversized”? Clearly these new cells would have been of crucial importance to us! Hardly an explanation of shrinkage, is it? And still you refuse to explain why you find my theory unacceptable.
Shrinkage must be recognized as clearly indicating we had excess neurons to begin with. I'm sure all our ancestors had similar brains. Further expansion is not something to be considered in any way as your wild explanation. And the complexification process was at the ready when the brain was designed and at work. Otherwise your tortured theory is acceptable.
Human evolution; savannah theory fading
DAVID: I think our brain acts like those in the past. Habilis and erectus had plenty of neurons to think and plan with to allow for the built-in complexification to work. All by God's designs.
dhw: I agree that our brains act like those in the past, except that when their brains’ capacity for complexification proved inadequate for new requirements, they expanded, whereas in our case, the new requirements were dealt with by enhanced complexification. I’m delighted to see that in this response you have dropped the notion that your God kept operating on various life forms in order to provide flippers or additional brain cells BEFORE they were required. […]
DAVID: Didn't you note I noted 'all by God's designs'?
I note that you did not mention your theory that your God kept operating on life forms and brains in order to change them before any changes were required. I am happy to allow for God as the designer of the mechanisms which enable complexification and expansion.
DAVID: You seem incapable of realizing how human you envision God to be.
dhw: In each of my theories I propose a particular theistic approach to evolution in order to explain the facts: experimentation, learning and getting new ideas as he goes along, deliberately creating a free-for-all as being more interesting than a puppet show (though always with the option of dabbling). I don’t see these “human” approaches as being any more “human” than your own belief that God enjoys creating and is interested in his creations, or – as you have now told us – that he wants us to think about him, recognize him, and ask questions.
DAVID: As explained in the other thread God's possible reactions to his creations are secondary events, never on purpose as a cause of creation.
I’m not talking about reactions! I asked you what was his purpose for creating humans, and the above was your answer.
DAVID: To explain again: We came with extra neurons in our brain so we could use our brain as we wished which gave us free will. The loss of superfluous neurons had nothing to do with losing free will with the remaining cells fully adequate to allow us to think freely.
dhw: So your new theory is that our extra neurons gave us free will – i.e. all our ancestors were automatons! Why, then, did these additional cells make our brain “oversized”? Clearly these new cells would have been of crucial importance to us! Hardly an explanation of shrinkage, is it? And still you refuse to explain why you find my theory unacceptable.
DAVID: Shrinkage must be recognized as clearly indicating we had excess neurons to begin with.
You are completely ignoring my proposal, which is that the neurons were NOT excessive to begin with. They would only have been added to the existing quantity if they had a function to perform! But later, when there were more new requirements, expansion was no longer practicable, and complexification took over, the latter proved so efficient that some cells which had earlier been necessary now become redundant.
DAVID: I'm sure all our ancestors had similar brains. Further expansion is not something to be considered in any way as your wild explanation. And the complexification process was at the ready when the brain was designed and at work. Otherwise your tortured theory is acceptable.
I have no idea what you mean by your second sentence. Yes, the complexification process was always present. I also have no idea what free will had to do with it, and I’m glad to see that has now disappeared. I also have no idea why my perfectly logical explanation of shrinkage is “tortured”.
Human evolution; savannah theory fading
by David Turell , Thursday, July 21, 2022, 14:50 (854 days ago) @ dhw
DAVID: You seem incapable of realizing how human you envision God to be.
dhw: In each of my theories I propose a particular theistic approach to evolution in order to explain the facts: experimentation, learning and getting new ideas as he goes along, deliberately creating a free-for-all as being more interesting than a puppet show (though always with the option of dabbling). I don’t see these “human” approaches as being any more “human” than your own belief that God enjoys creating and is interested in his creations, or – as you have now told us – that he wants us to think about him, recognize him, and ask questions.
DAVID: As explained in the other thread God's possible reactions to his creations are secondary events, never on purpose as a cause of creation.
dhw: I’m not talking about reactions! I asked you what was his purpose for creating humans, and the above was your answer.
The simple answer was His right to produce thinking beings for no other purpose than that.
DAVID: To explain again: We came with extra neurons in our brain so we could use our brain as we wished which gave us free will. The loss of superfluous neurons had nothing to do with losing free will with the remaining cells fully adequate to allow us to think freely.dhw: So your new theory is that our extra neurons gave us free will – i.e. all our ancestors were automatons! Why, then, did these additional cells make our brain “oversized”? Clearly these new cells would have been of crucial importance to us! Hardly an explanation of shrinkage, is it? And still you refuse to explain why you find my theory unacceptable.
DAVID: Shrinkage must be recognized as clearly indicating we had excess neurons to begin with.
dhw: You are completely ignoring my proposal, which is that the neurons were NOT excessive to begin with. They would only have been added to the existing quantity if they had a function to perform! But later, when there were more new requirements, expansion was no longer practicable, and complexification took over, the latter proved so efficient that some cells which had earlier been necessary now become redundant.
DAVID: I'm sure all our ancestors had similar brains. Further expansion is not something to be considered in any way as your wild explanation. And the complexification process was at the ready when the brain was designed and at work. Otherwise your tortured theory is acceptable.
dhw: I have no idea what you mean by your second sentence. Yes, the complexification process was always present. I also have no idea what free will had to do with it, and I’m glad to see that has now disappeared. I also have no idea why my perfectly logical explanation of shrinkage is “tortured”.
Our brain came with excess neurons or shrinkage could not logically have occurred. That cells had to be used and then had to be thrown aways makes no sense. As we civilized our brains had constant expansion of use. Our brain arrived with the complexification mechanism in place, to be used as required, as you agree.
Human evolution; brain different from Neanderthal
by David Turell , Saturday, July 30, 2022, 18:41 (845 days ago) @ David Turell
A look at genetic differences:
https://phys.org/news/2022-07-difference-brain-differs-neanderthals-modern.html
"The neocortex, the largest part of the outer layer of the brain, is unique to mammals and crucial for many cognitive capacities. It expanded dramatically during human evolution in species ancestral to both Neanderthals and modern humans, resulting that both Neanderthals and modern humans having brains of similar sizes. However, almost nothing is known about how modern human and Neanderthal brains may have differed in terms of their development and function.
"Researchers from the Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG) in Dresden and the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) in Leipzig have now discovered that neural stem cells—the cells from which neurons in the developing neocortex derive—spend more time preparing their chromosomes for division in modern humans than in Neanderthals. This results in fewer errors when chromosomes are distributed to the daughter cells in modern humans than in Neanderthals or chimpanzees, and could have consequences for how the brain develops and functions. This study shows cellular differences in the development of the brain between modern humans and Neanderthals.
"After the ancestors of modern humans split from those of Neanderthals and Denisovans, their Asian relatives, about one hundred amino acids, the building blocks of proteins in cells and tissues, changed in modern humans and spread to almost all modern humans. The biological significance of these changes is largely unknown. However, six of those amino acid changes occurred in three proteins that play key roles in the distribution of chromosomes, the carriers of genetic information, to the two daughter cells during cell division.
***
"'We found that three modern human amino acids in two of the proteins cause a longer metaphase, a phase where chromosomes are prepared for cell division, and this results in fewer errors when the chromosomes are distributed to the daughter cells of the neural stem cells, just like in modern humans." To check if the Neanderthal set of amino acids have the opposite effect, the researchers then introduced the ancestral amino acids in human brain organoids—miniature organ-like structures that can be grown from human stem cells in cell culture dishes in the lab and that mimic aspects of early human brain development. "In this case, metaphase became shorter and we found more chromosome distribution errors." According to Mora-Bermúdez, this shows that those three modern human amino acid changes in the proteins known as KIF18a and KNL1 are responsible for the fewer chromosome distribution mistakes seen in modern humans as compared to Neanderthal models and chimpanzees. He adds that "having mistakes in the number of chromosomes is usually not a good idea for cells, as can be seen in disorders like trisomies and cancer."
"'Our study implies that some aspects of modern human brain evolution and function may be independent of brain size since Neanderthals and modern humans have similar-sized brains. The findings also suggest that brain function in Neanderthals may have been more affected by chromosome errors than that of modern humans," says Wieland Huttner, who co-supervised the study. Svante Pääbo, who also co-supervised the study, adds that "future studies are needed to investigate whether the decreased error rate affects modern human traits related to brain function.'" (my bold)
Comment: we have aways suspected it is not just size that counts but proper organization for more complex function. I suspect the difference with Neanderthals is more than errors in genetics but a higher degree of human brain complexity.
Human evolution; savannah theory fading
DAVID: You seem incapable of realizing how human you envision God to be.
dhw: In each of my theories I propose a particular theistic approach to evolution in order to explain the facts: experimentation, learning and getting new ideas as he goes along, deliberately creating a free-for-all as being more interesting than a puppet show (though always with the option of dabbling). I don’t see these “human” approaches as being any more “human” than your own belief that God enjoys creating and is interested in his creations, or – as you have now told us – that he wants us to think about him, recognize him, and ask questions.
DAVID: As explained in the other thread God's possible reactions to his creations are secondary events, never on purpose as a cause of creation.
dhw: I’m not talking about reactions! I asked you what was his purpose for creating humans, and the above was your answer.
DAVID: The simple answer was His right to produce thinking beings for no other purpose than that.
You have proposed that he enjoys creating and is interested in his creations, and he might have produced thinking beings so that they could think about him and recognize him etc. I find these theories perfectly acceptable, and have asked why you consider them to be less “humanizing” than my own. Opting to have no theories at all about his purpose is, of course, another option.
Brain expansion
DAVID: Our brain came with excess neurons or shrinkage could not logically have occurred. That cells had to be used and then had to be thrown away makes no sense.
You keep ignoring my explanation, so all I can do is repeat it. Our brain came with more neurons than those of our predecessors. I propose that those neurons would have been added for a specific purpose, though we can only speculate on what that might have been. (Weirdly, you proposed the purpose was to give us free will, as if our earlier ancestors were all automatons.) However, as the brain was no longer capable of further expansion – probably because that would have involved major changes to the anatomy – complexification took over from expansion and proved so efficient that cells which had been essential in the past now became redundant. Hence shrinkage. You have accepted this explanation, but now you ignore it again.
DAVID: As we civilized our brains had constant expansion of use. Our brain arrived with the complexification mechanism in place, to be used as required, as you agree.
Yes, that is precisely what I propose: our new uses were implemented through complexification and not through the addition of new cells. And complexification proved to be so efficient etc., as bolded above. What’s the problem?
Human evolution; savannah theory fading
by David Turell , Monday, August 01, 2022, 20:07 (843 days ago) @ dhw
DAVID: As explained in the other thread God's possible reactions to his creations are secondary events, never on purpose as a cause of creation.
dhw: I’m not talking about reactions! I asked you what was his purpose for creating humans, and the above was your answer.
DAVID: The simple answer was His right to produce thinking beings for no other purpose than that.
dhw: You have proposed that he enjoys creating and is interested in his creations, and he might have produced thinking beings so that they could think about him and recognize him etc. I find these theories perfectly acceptable, and have asked why you consider them to be less “humanizing” than my own. Opting to have no theories at all about his purpose is, of course, another option.
Your humanized God seeks entertainment and allows evolution to proceed as a free-for-all. My view of God sees Him as fully purposeful at all times, creating without any self-needy desires.
Brain expansion
DAVID: Our brain came with excess neurons or shrinkage could not logically have occurred. That cells had to be used and then had to be thrown away makes no sense.dhw: You keep ignoring my explanation, so all I can do is repeat it. Our brain came with more neurons than those of our predecessors. I propose that those neurons would have been added for a specific purpose, though we can only speculate on what that might have been. (Weirdly, you proposed the purpose was to give us free will, as if our earlier ancestors were all automatons.)
We've discussed this in the past and I've said all previous brains were similar and all had free will. I doubt they shrunk as ours has. God added those extra neurons to allow us freedom of brain development as we learned to fully use it.
dhw: However, as the brain was no longer capable of further expansion – probably because that would have involved major changes to the anatomy – complexification took over from expansion and proved so efficient that cells which had been essential in the past now became redundant. Hence shrinkage. You have accepted this explanation, but now you ignore it again.
Your continual use of an anatomic theory dismisses the evidence from the Neanderthals whose skulls were bigger with no problem evident. We both agree about shrinkage.
DAVID: As we civilized our brains had constant expansion of use. Our brain arrived with the complexification mechanism in place, to be used as required, as you agree.dhw: Yes, that is precisely what I propose: our new uses were implemented through complexification and not through the addition of new cells. And complexification proved to be so efficient etc., as bolded above. What’s the problem?
The problem is your interpretation of the original added neurons and how they became present. There is no known required mew complex usage that drove their appearance from a natural cause, considering the simplistic lifestyle of our immediate predecessors.
Human evolution; brain case size unchanged recently
by David Turell , Monday, August 01, 2022, 21:32 (843 days ago) @ David Turell
No change for 200,000 years, but brain shape does change:
https://www.newscientist.com/article/2331652-shape-of-human-brain-has-barely-changed-in...
"The physical transformation of the human cranium over the past 160,000 years was probably driven by alterations in the face resulting from diet and lifestyle changes, not from the evolution of the brain itself as previously thought, a study has found.
"The cranium, or braincase, of early modern humans dating back 200,000 years isn’t much different in size from those today, but has a significantly different shape, suggesting that the brain has become rounder over time.
"The leading hypothesis is that changes in behaviour, such as the development of tools and art, caused the shape of the Homo sapiens brain to change and, in turn, the skull that protects it. (my bold)
***
{"The team was surprised to find that while the size and proportions of the skulls of H. sapiens children from 160,000 years ago were largely comparable to infants today, the adults looked remarkably different to those of modern adults, with much longer faces and more pronounced feature
***
"If the fossil children – with near fully developed brains – resemble living ones, but fossil adults had very different skulls, we can rule out that brains have changed significantly in shape, says Zollikofer. “And if it’s not the brain driving this change, we must look for something else, like breathing, eating or moving.”
***
"Faces in modern humans are far smaller, with subtler indentation, than those of their ancestors. Studies show that this change accelerated when hunter-gatherers became agriculturalists around 12,000 years ago and ate softer foods, probably due to less loading on the skull from chewing."
Comment: so, the brain shape changed, undoubtedly due to our new uses of it with complexification and shrinkage as a result. No evidence for dhw's weird anatomic theory that a larger skull could not be accommodated.
Human evolution; savannah theory fading
Brain expansion
DAVID: Our brain came with excess neurons or shrinkage could not logically have occurred. That cells had to be used and then had to be thrown away makes no sense.
dhw: You keep ignoring my explanation, so all I can do is repeat it. Our brain came with more neurons than those of our predecessors. I propose that those neurons would have been added for a specific purpose, though we can only speculate on what that might have been. (Weirdly, you proposed the purpose was to give us free will, as if our earlier ancestors were all automatons.)
DAVID: We've discussed this in the past and I've said all previous brains were similar and all had free will.
DAVID (July 19th): We came with extra neurons in our brain so we could use our brain as we wished which gave us free will.
If the extra neurons gave us free will, then clearly you think our precursors could not have had free will, but I’m pleased to see that you are now disowning this theory.
DAVID: I doubt they shrunk as ours has. God added those extra neurons to allow us freedom of brain development as we learned to fully use it.
There would have been no reason for them to shrink. They would have expanded in order to meet new requirements. I have no idea what your second sentence means. Do you think the gradual increase in earlier brain sizes and accomplishments indicated that there was no “freedom of brain development”? In your next comment, you agree to my explanation of shrinkage, so why are you inserting this woolly explanation here?
dhw: However, as the brain was no longer capable of further expansion – probably because that would have involved major changes to the anatomy – complexification took over from expansion and proved so efficient that cells which had been essential in the past now became redundant. Hence shrinkage. You have accepted this explanation, but now you ignore it again.
DAVID: Your continual use of an anatomic theory dismisses the evidence from the Neanderthals whose skulls were bigger with no problem evident. We both agree about shrinkage.
I said “probably”, but do by all means let us know your own theory about why sapiens’ brain stopped expanding and complexification took over. Thank you for once again accepting my explanation of shrinkage. I trust that will mark the end of this particular discussion.
DAVID: As we civilized our brains had constant expansion of use. Our brain arrived with the complexification mechanism in place, to be used as required, as you agree.
dhw: Yes, that is precisely what I propose: our new uses were implemented through complexification and not through the addition of new cells. And complexification proved to be so efficient etc., as bolded above. What’s the problem?
DAVID: The problem is your interpretation of the original added neurons and how they became present. There is no known required mew complex usage that drove their appearance from a natural cause, considering the simplistic lifestyle of our immediate predecessors.
Nobody knows precisely what new usages caused new cells to be added to any of the brains from our earliest ancestors onwards. But in some cases they appear to have coincided with changes such as bipedalism, new artefacts, new lifestyles (hunters/gatherers)….It is not unreasonable to suppose that something new caused the sapiens expansion, as opposed to your God performing an operation on a group of sleeping Moroccans to prepare them for innovations that wouldn’t take place for a couple of thousand years.
Braincase size unchanged
QUOTES: "The physical transformation of the human cranium over the past 160,000 years was probably driven by alterations in the face resulting from diet and lifestyle changes, not from the evolution of the brain itself as previously thought, a study has found.”
"The cranium, or braincase, of early modern humans dating back 200,000 years isn’t much different in size from those today, but has a significantly different shape, suggesting that the brain has become rounder over time."
"The leading hypothesis is that changes in behaviour, such as the development of tools and art, caused the shape of the Homo sapiens brain to change and, in turn, the skull that protects it." (David’s bold)
DAVID: so, the brain shape changed, undoubtedly due to our new uses of it with complexification and shrinkage as a result. No evidence for dhw's weird anatomic theory that a larger skull could not be accommodated.
The article tells us that the size remained unchanged! How does that come to mean that a larger skull COULD have been accommodated?
Human evolution; savannah theory fading
by David Turell , Tuesday, August 02, 2022, 19:07 (842 days ago) @ dhw
Brain expansion
DAVID: We've discussed this in the past and I've said all previous brains were similar and all had free will.
DAVID (July 19th): We came with extra neurons in our brain so we could use our brain as we wished which gave us free will.
dhw: If the extra neurons gave us free will, then clearly you think our precursors could not have had free will, but I’m pleased to see that you are now disowning this theory.
I don't know how you derived that weird interpretation.
DAVID: I doubt they shrunk as ours has. God added those extra neurons to allow us freedom of brain development as we learned to fully use it.dhw: There would have been no reason for them to shrink. They would have expanded in order to meet new requirements. I have no idea what your second sentence means. Do you think the gradual increase in earlier brain sizes and accomplishments indicated that there was no “freedom of brain development”? In your next comment, you agree to my explanation of shrinkage, so why are you inserting this woolly explanation here?
If you have a brain that is little used compared to capacity, as new concepts appear that is 'learning to use it'. That is a 'freedom of development'.
dhw: However, as the brain was no longer capable of further expansion – probably because that would have involved major changes to the anatomy – complexification took over from expansion and proved so efficient that cells which had been essential in the past now became redundant. Hence shrinkage. You have accepted this explanation, but now you ignore it again.DAVID: Your continual use of an anatomic theory dismisses the evidence from the Neanderthals whose skulls were bigger with no problem evident. We both agree about shrinkage.
dhw: I said “probably”, but do by all means let us know your own theory about why sapiens’ brain stopped expanding and complexification took over. Thank you for once again accepting my explanation of shrinkage. I trust that will mark the end of this particular discussion.
God gave us an adequate brain for all future uses and extra neurons to allow us to shape those uses, with a way to discard extra neurons in complexifixation
DAVID: The problem is your interpretation of the original added neurons and how they became present. There is no known required mew complex usage that drove their appearance from a natural cause, considering the simplistic lifestyle of our immediate predecessors.dhw: Nobody knows precisely what new usages caused new cells to be added to any of the brains from our earliest ancestors onwards. But in some cases they appear to have coincided with changes such as bipedalism, new artefacts, new lifestyles (hunters/gatherers)….It is not unreasonable to suppose that something new caused the sapiens expansion, as opposed to your God performing an operation on a group of sleeping Moroccans to prepare them for innovations that wouldn’t take place for a couple of thousand years.
Same old commentary. What new single event required such a jump in brain thought aability?
Braincase size unchangedQUOTES: "The physical transformation of the human cranium over the past 160,000 years was probably driven by alterations in the face resulting from diet and lifestyle changes, not from the evolution of the brain itself as previously thought, a study has found.”
"The cranium, or braincase, of early modern humans dating back 200,000 years isn’t much different in size from those today, but has a significantly different shape, suggesting that the brain has become rounder over time."
"The leading hypothesis is that changes in behaviour, such as the development of tools and art, caused the shape of the Homo sapiens brain to change and, in turn, the skull that protects it." (David’s bold)
DAVID: so, the brain shape changed, undoubtedly due to our new uses of it with complexification and shrinkage as a result. No evidence for dhw's weird anatomic theory that a larger skull could not be accommodated.
dhw: The article tells us that the size remained unchanged! How does that come to mean that a larger skull COULD have been accommodated?
The Neanderthal's accommodated a larger brain and skull. That destroys your accommodation theory.
Human evolution; savannah theory fading
Brain expansion
DAVID: We've discussed this in the past and I've said all previous brains were similar and all had free will.
DAVID (July 19th): We came with extra neurons in our brain so we could use our brain as we wished which gave us free will. (dhw's bold)
dhw: If the extra neurons gave us free will, then clearly you think our precursors could not have had free will, but I’m pleased to see that you are now disowning this theory.
DAVID: I don't know how you derived that weird interpretation.
From your statement bolded above. I’m glad you now agree that it is weird.
DAVID: I doubt they shrunk as ours has. God added those extra neurons to allow us freedom of brain development as we learned to fully use it.
dhw: There would have been no reason for them to shrink. They would have expanded in order to meet new requirements. I have no idea what your second sentence means. Do you think the gradual increase in earlier brain sizes and accomplishments indicated that there was no “freedom of brain development”? In your next comment, you agree to my explanation of shrinkage, so why are you inserting this woolly explanation here?
DAVID: If you have a brain that is little used compared to capacity, as new concepts appear that is 'learning to use it'. That is a 'freedom of development'.
I propose that our additional cells followed exactly the same pattern as before: all our ancestors had “freedom of development” – which resulted in the addition of cells when needed! But for reasons unknown, we reached a stage at which complexification took over from expansion and proved so efficient that some cells became redundant. You agree, so what’s the problem?
DAVID: The problem is your interpretation of the original added neurons and how they became present. There is no known required mew complex usage that drove their appearance from a natural cause, considering the simplistic lifestyle of our immediate predecessors.
dhw: Nobody knows precisely what new usages caused new cells to be added to any of the brains from our earliest ancestors onwards. But in some cases they appear to have coincided with changes such as bipedalism, new artefacts, new lifestyles (hunters/gatherers)….It is not unreasonable to suppose that something new caused the sapiens expansion, as opposed to your God performing an operation on a group of sleeping Moroccans to prepare them for innovations that wouldn’t take place for a couple of thousand years.
DAVID: Same old commentary. What new single event required such a jump in brain thought ability?
You are asking me to solve mysteries which nobody else has solved. But I have given you examples of past events that might well have required additional cells, and so it is not unreasonable to suppose that the same process would have repeated itself.
Braincase size unchanged
QUOTES: "The cranium, or braincase, of early modern humans dating back 200,000 years isn’t much different in size from those today, but has a significantly different shape, suggesting that the brain has become rounder over time."
"The leading hypothesis is that changes in behaviour, such as the development of tools and art, caused the shape of the Homo sapiens brain to change and, in turn, the skull that protects it[/b]." (David’s bold)
DAVID: so, the brain shape changed, undoubtedly due to our new uses of it with complexification and shrinkage as a result. No evidence for dhw's weird anatomic theory that a larger skull could not be accommodated.
dhw: The article tells us that the size remained unchanged! How does that come to mean that a larger skull COULD have been accommodated?
DAVID: The Neanderthal's accommodated a larger brain and skull. That destroys your accommodation theory.
You tried to use the article as proof that a larger size could be accommodated, but it shows clearly that it was the shape and not the size that changed. Neanderthals were a different build from us, and their brain size was not massively greater than ours, and may even have been the same size as those of their contemporary sapiens. But again, you are asking me to solve problems that nobody else has solved. And you have not yet given us your own theory as to why our brain stopped expanding and reverted to enhanced complexification instead. Please tell us.
Human evolution; savannah theory fading
by David Turell , Wednesday, August 03, 2022, 17:52 (841 days ago) @ dhw
Brain expansion
DAVID: If you have a brain that is little used compared to capacity, as new concepts appear that is 'learning to use it'. That is a 'freedom of development'.
dhw: I propose that our additional cells followed exactly the same pattern as before: all our ancestors had “freedom of development” – which resulted in the addition of cells when needed! But for reasons unknown, we reached a stage at which complexification took over from expansion and proved so efficient that some cells became redundant. You agree, so what’s the problem?
That is not my position. Based on how our brain arrived with excess neurons, I'm convinced Habilis and Erectus had similar beginning excess capacities. Our brain must reflect the past forms.
DAVID: The problem is your interpretation of the original added neurons and how they became present. There is no known required mew complex usage that drove their appearance from a natural cause, considering the simplistic lifestyle of our immediate predecessors.dhw: Nobody knows precisely what new usages caused new cells to be added to any of the brains from our earliest ancestors onwards. But in some cases they appear to have coincided with changes such as bipedalism, new artefacts, new lifestyles (hunters/gatherers)….It is not unreasonable to suppose that something new caused the sapiens expansion, as opposed to your God performing an operation on a group of sleeping Moroccans to prepare them for innovations that wouldn’t take place for a couple of thousand years.
DAVID: Same old commentary. What new single event required such a jump in brain thought ability?
dhw: You are asking me to solve mysteries which nobody else has solved. But I have given you examples of past events that might well have required additional cells, and so it is not unreasonable to suppose that the same process would have repeated itself.
So you assume the needed extra cells in new species simply appeared magically? New designs require a designer.
Braincase size unchangedQUOTES: "The cranium, or braincase, of early modern humans dating back 200,000 years isn’t much different in size from those today, but has a significantly different shape, suggesting that the brain has become rounder over time."
"The leading hypothesis is that changes in behaviour, such as the development of tools and art, caused the shape of the Homo sapiens brain to change and, in turn, the skull that protects it[/b]." (David’s bold)
DAVID: so, the brain shape changed, undoubtedly due to our new uses of it with complexification and shrinkage as a result. No evidence for dhw's weird anatomic theory that a larger skull could not be accommodated.
dhw: The article tells us that the size remained unchanged! How does that come to mean that a larger skull COULD have been accommodated?
DAVID: The Neanderthal's accommodated a larger brain and skull. That destroys your accommodation theory.
dhw: You tried to use the article as proof that a larger size could be accommodated, but it shows clearly that it was the shape and not the size that changed. Neanderthals were a different build from us, and their brain size was not massively greater than ours, and may even have been the same size as those of their contemporary sapiens. But again, you are asking me to solve problems that nobody else has solved. And you have not yet given us your own theory as to why our brain stopped expanding and reverted to enhanced complexification instead. Please tell us.
I have told you previously: God designed our brain as an endpoint in evolution. It came with all the capacity it would ever need. Its conceptualizing ability seems endless based on present evidence of ideations. It came oversized to allow us to mold it as we willed. It came with a complexification mechanism to accommodate our free use of it.
Human evolution; savannah theory fading
Brain expansion
DAVID: If you have a brain that is little used compared to capacity, as new concepts appear that is 'learning to use it'. That is a 'freedom of development'.
dhw: I propose that our additional cells followed exactly the same pattern as before: all our ancestors had “freedom of development” – which resulted in the addition of cells when needed! But for reasons unknown, we reached a stage at which complexification took over from expansion and proved so efficient that some cells became redundant. You agree, so what’s the problem?
DAVID: That is not my position. Based on how our brain arrived with excess neurons, I'm convinced Habilis and Erectus had similar beginning excess capacities. Our brain must reflect the past forms.
This is new. There is no evidence that Habilis and erectus brains shrank – on the contrary, we know that erectus’s brain expanded, i.e. added new cells, presumably as and when there were new requirements. Until now, you have focused entirely on the astonishing jump in sapiens’ thought capabilities and “excess” cells (which I propose were not excess at all, but were necessary at the time), as in your next question:
DAVID: What new single event required such a jump in brain thought ability?
dhw: You are asking me to solve mysteries which nobody else has solved. But I have given you examples of past events that might well have required additional cells, and so it is not unreasonable to suppose that the same process would have repeated itself.
DAVID: So you assume the needed extra cells in new species simply appeared magically? New designs require a designer.
There is no magic if you accept the theory of cellular intelligence (possibly designed by your God)! At every stage, when complexification could no longer cope, new conditions/discoveries/inventions/tools/lifestyles required additional cells for their implementation. But for some unknown reason, sapiens’ brain generally stopped expanding, and complexification took over, with such efficiency that cells which had previously been necessary then became redundant. You keep agreeing with this last explanation, so I don’t know why you keep faffing around with new objections.
Braincase size unchanged
QUOTES: "The cranium, or braincase, of early modern humans dating back 200,000 years isn’t much different in size from those today, but has a significantly different shape, suggesting that the brain has become rounder over time."
"The leading hypothesis is that changes in behaviour, such as the development of tools and art, caused the shape of the Homo sapiens brain to change and, in turn, the skull that protects it." (David’s bold)
DAVID: so, the brain shape changed, undoubtedly due to our new uses of it with complexification and shrinkage as a result. No evidence for dhw's weird anatomic theory that a larger skull could not be accommodated.
dhw: The article tells us that the size remained unchanged! How does that come to mean that a larger skull COULD have been accommodated?
DAVID: The Neanderthal's accommodated a larger brain and skull. That destroys your accommodation theory.
dhw: You tried to use the article as proof that a larger size could be accommodated, but it shows clearly that it was the shape and not the size that changed. Neanderthals were a different build from us, and their brain size was not massively greater than ours, and may even have been the same size as those of their contemporary sapiens. But again, you are asking me to solve problems that nobody else has solved. And you have not yet given us your own theory as to why our brain stopped expanding and reverted to enhanced complexification instead. Please tell us.
DAVID: I have told you previously: God designed our brain as an endpoint in evolution. It came with all the capacity it would ever need. Its conceptualizing ability seems endless based on present evidence of ideations. It came oversized to allow us to mold it as we willed. It came with a complexification mechanism to accommodate our free use of it.
You are talking as if your God designed our brain from scratch! It evolved from all the earlier brains and it reached a point at which it stopped expanding. You have agreed that all previous brains would have had a complexification mechanism, but at all stages except ours, this proved inadequate for new requirements and so they produced additional cells. I propose that no brain, including our own, was “oversized”, and why on earth do you think that the cells of erectus’s brain could not complexify as they “willed”. Was erectus a robot? Did habilis not have “free use” of his brain?
Human evolution; savannah theory fading
by David Turell , Thursday, August 04, 2022, 19:09 (840 days ago) @ dhw
Brain expansion
dhw: I propose that our additional cells followed exactly the same pattern as before: all our ancestors had “freedom of development” – which resulted in the addition of cells when needed! But for reasons unknown, we reached a stage at which complexification took over from expansion and proved so efficient that some cells became redundant. You agree, so what’s the problem?
DAVID: That is not my position. Based on how our brain arrived with excess neurons, I'm convinced Habilis and Erectus had similar beginning excess capacities. Our brain must reflect the past forms.
dhw: This is new. There is no evidence that Habilis and erectus brains shrank – on the contrary, we know that erectus’s brain expanded, i.e. added new cells, presumably as and when there were new requirements.
There are not enough fossils to answer all question, but brain shrinkage is accumpianed without skull case shrinkage.
dhw: Until now, you have focused entirely on the astonishing jump in sapiens’ thought capabilities and “excess” cells (which I propose were not excess at all, but were necessary at the time), as in your next question:
DAVID: What new single event required such a jump in brain thought ability?
dhw: You are asking me to solve mysteries which nobody else has solved. But I have given you examples of past events that might well have required additional cells, and so it is not unreasonable to suppose that the same process would have repeated itself.
DAVID: So you assume the needed extra cells in new species simply appeared magically? New designs require a designer.
dhw: There is no magic if you accept the theory of cellular intelligence (possibly designed by your God)! At every stage, when complexification could no longer cope, new conditions/discoveries/inventions/tools/lifestyles required additional cells for their implementation. But for some unknown reason, sapiens’ brain generally stopped expanding, and complexification took over, with such efficiency that cells which had previously been necessary then became redundant. You keep agreeing with this last explanation, so I don’t know why you keep faffing around with new objections.
I agree with your description of events but reject your intelligent cell theory.
Braincase size unchanged
QUOTES: "The cranium, or braincase, of early modern humans dating back 200,000 years isn’t much different in size from those today, but has a significantly different shape, suggesting that the brain has become rounder over time."
"The leading hypothesis is that changes in behaviour, such as the development of tools and art, caused the shape of the Homo sapiens brain to change and, in turn, the skull that protects it." (David’s bold)DAVID: so, the brain shape changed, undoubtedly due to our new uses of it with complexification and shrinkage as a result. No evidence for dhw's weird anatomic theory that a larger skull could not be accommodated.
dhw: The article tells us that the size remained unchanged! How does that come to mean that a larger skull COULD have been accommodated?
DAVID: The Neanderthal's accommodated a larger brain and skull. That destroys your accommodation theory.
dhw: You tried to use the article as proof that a larger size could be accommodated, but it shows clearly that it was the shape and not the size that changed. Neanderthals were a different build from us, and their brain size was not massively greater than ours, and may even have been the same size as those of their contemporary sapiens. But again, you are asking me to solve problems that nobody else has solved. And you have not yet given us your own theory as to why our brain stopped expanding and reverted to enhanced complexification instead. Please tell us.
DAVID: I have told you previously: God designed our brain as an endpoint in evolution. It came with all the capacity it would ever need. Its conceptualizing ability seems endless based on present evidence of ideations. It came oversized to allow us to mold it as we willed. It came with a complexification mechanism to accommodate our free use of it.
dhw:n You are talking as if your God designed our brain from scratch! It evolved from all the earlier brains and it reached a point at which it stopped expanding. You have agreed that all previous brains would have had a complexification mechanism, but at all stages except ours, this proved inadequate for new requirements and so they produced additional cells. I propose that no brain, including our own, was “oversized”, and why on earth do you think that the cells of erectus’s brain could not complexify as they “willed”. Was erectus a robot? Did habilis not have “free use” of his brain?
God does design from scratch when first brains appeared and designed all future modifications. I've said previously erectus and habilis had free ill. You've invented my mind as changing.
Human evolution; savannah theory fading
Brain expansion
dhw: I propose that our additional cells followed exactly the same pattern as before: all our ancestors had “freedom of development” – which resulted in the addition of cells when needed! But for reasons unknown, we reached a stage at which complexification took over from expansion and proved so efficient that some cells became redundant. You agree, so what’s the problem?
DAVID: That is not my position. Based on how our brain arrived with excess neurons, I'm convinced Habilis and Erectus had similar beginning excess capacities. Our brain must reflect the past forms.
dhw: This is new. There is no evidence that Habilis and erectus brains shrank – on the contrary, we know that erectus’s brain expanded, i.e. added new cells, presumably as and when there were new requirements.
DAVID: There are not enough fossils to answer all question, but brain shrinkage is accumpianed without skull case shrinkage.
Correct. So what makes you think that habilis and erectus began with “excess capacities”, as opposed to their having acquired new cells to meet new requirements when their existing capacity for complexification had been exhausted?
DAVID: So you assume the needed extra cells in new species simply appeared magically? New designs require a designer.
dhw: There is no magic if you accept the theory of cellular intelligence (possibly designed by your God)! At every stage, when complexification could no longer cope, new conditions/discoveries/inventions/tools/lifestyles required additional cells for their implementation. But for some unknown reason, sapiens’ brain generally stopped expanding, and complexification took over, with such efficiency that cells which had previously been necessary then became redundant. You keep agreeing with this last explanation, so I don’t know why you keep faffing around with new objections.
DAVID: I agree with your description of events but reject your intelligent cell theory.
So long as you agree with the theory that new cells were acquired when new conditions etc. demanded an increase in capacity, we can leave it open as to the nature of the mechanism. My objection is to your theory that new “excess” cells were acquired when they were not needed, purely in anticipation of future requirements that did not yet exist.
Dhw: […] [i]you have not yet given us your own theory as to why our brain stopped expanding and reverted to enhanced complexification instead. Please tell us.[/i]
DAVID: I have told you previously: God designed our brain as an endpoint in evolution. It came with all the capacity it would ever need. Its conceptualizing ability seems endless based on present evidence of ideations. It came oversized to allow us to mold it as we willed. It came with a complexification mechanism to accommodate our free use of it.
dhw: You are talking as if your God designed our brain from scratch! It evolved from all the earlier brains and it reached a point at which it stopped expanding. You have agreed that all previous brains would have had a complexification mechanism, but at all stages except ours, this proved inadequate for new requirements and so they produced additional cells. I propose that no brain, including our own, was “oversized”, and why on earth do you think that the cells of erectus’s brain could not complexify as they “willed”. Was erectus a robot? Did habilis not have “free use” of his brain?
DAVID: God does design from scratch when first brains appeared and designed all future modifications. I've said previously erectus and habilis had free will. You've invented my mind as changing.
I asked you to give us your explanation for why our brain stopped expanding and complexification took over. Your explanation is that our brain was “oversized” (whereas earlier you agreed that “cells which had previously been necessary then became redundant”) and the new cells enabled us to “mold it as we will”, and it came with a “complexification mechanism to accommodate our free use of it”. But these characteristics are no different from those of the brains that preceded ours, so how does the above explain why our brain stopped expanding???
DAVID: (under “prediction machine”) As in the past I've always noted the brain is designed to help us use it.
I’d have thought that every cell in every organ and organism was “designed to be used” by the organism.
Human evolution; savannah theory fading
by David Turell , Friday, August 05, 2022, 20:40 (839 days ago) @ dhw
Brain expansion
DAVID: There are not enough fossils to answer all question, but brain shrinkage is accumpianed without skull case shrinkage.
dhw: Correct. So what makes you think that habilis and erectus began with “excess capacities”, as opposed to their having acquired new cells to meet new requirements when their existing capacity for complexification had been exhausted?
Don't forget evolution is a process is which new processes build on earlier ones. Don't you think our brain is built from previous functioning brains, so why can't complexification be previously present?
DAVID: So you assume the needed extra cells in new species simply appeared magically? New designs require a designer.dhw: There is no magic if you accept the theory of cellular intelligence (possibly designed by your God)! At every stage, when complexification could no longer cope, new conditions/discoveries/inventions/tools/lifestyles required additional cells for their implementation. But for some unknown reason, sapiens’ brain generally stopped expanding, and complexification took over, with such efficiency that cells which had previously been necessary then became redundant. You keep agreeing with this last explanation, so I don’t know why you keep faffing around with new objections.
DAVID: I agree with your description of events but reject your intelligent cell theory.
dhw: So long as you agree with the theory that new cells were acquired when new conditions etc. demanded an increase in capacity, we can leave it open as to the nature of the mechanism. My objection is to your theory that new “excess” cells were acquired when they were not needed, purely in anticipation of future requirements that did not yet exist.
A designer would logically design a brain for free usage which would implies shrinkage could occur as brain complexifies.
Dhw: […] [i]you have not yet given us your own theory as to why our brain stopped expanding and reverted to enhanced complexification instead. Please tell us.[/i]DAVID: I have told you previously: God designed our brain as an endpoint in evolution. It came with all the capacity it would ever need. Its conceptualizing ability seems endless based on present evidence of ideations. It came oversized to allow us to mold it as we willed. It came with a complexification mechanism to accommodate our free use of it.
dhw: I asked you to give us your explanation for why our brain stopped expanding and complexification took over. Your explanation is that our brain was “oversized” (whereas earlier you agreed that “cells which had previously been necessary then became redundant”) and the new cells enabled us to “mold it as we will”, and it came with a “complexification mechanism to accommodate our free use of it”. But these characteristics are no different from those of the brains that preceded ours, so how does the above explain why our brain stopped expanding???
You constantly fail to think as a designer would. God made our brain oversized so we could develop its use as we willed. Free will!!! It was so complete in its capacities further enlargement was never necessary. I view us as a finished endopint.
DAVID: (under “prediction machine”) As in the past I've always noted the brain is designed to help us use it.dhw: I’d have thought that every cell in every organ and organism was “designed to be used” by the organism.
Off the subject of predictive capacity.
Human evolution; new study says our brain did not shrink
by David Turell , Friday, August 05, 2022, 22:23 (839 days ago) @ David Turell
A very new analysis:
https://phys.org/news/2022-08-human-brain-years.html
"Last year, a group of scientists made headlines when they concluded that the human brain shrank during the transition to modern urban societies about 3,000 years ago because, they said, our ancestors' ability to store information externally in social groups decreased our need to maintain large brains. Their hypothesis, which explored decades-old ideas on the evolutionary reduction of modern human brain size, was based on a comparison to evolutionary patterns seen in ant colonies.
"In a new paper published last week in Frontiers in Ecology and Evolution, the UNLV-led team analyzed the dataset that the research group from last year's study used and dismissed their findings.
***
"'We re-examined the dataset from DeSilva et al. and found that human brain size has not changed in 30,000 years, and probably not in 300,000 years," Villmoare said. "In fact, based on this dataset, we can identify no reduction in brain size in modern humans over any time-period since the origins of our species."
"The UNLV research team questioned several of the hypotheses that DeSilva et. al gleaned from a dataset of nearly 1,000 early human fossil and museum specimens, including:
"The UNLV team says the rise of agriculture and complex societies occurred at different times around the globe—meaning there should be variation in timing of skull changes seen in different populations. However, DeSilva's dataset sampled only 23 crania from the timeframe critical to the brain shrinkage hypothesis and lumped together specimens from locations including England, China, Mali, and Algeria.
"The dataset is heavily skewed because more than half of the 987 skulls examined represent only the last 100 years of a 9.8-million-year span of time—and therefore don't give scientists a good idea of how much cranial size has changed over time.
"Multiple hypotheses on causes of reduction in modern human brain size need to be reassessed if human brains haven't actually changed in size since the arrival of our species."
Comment: if true, this changes the whole tone of our discussion about modern humans. It means complexification occurs without shrinkage.
Human evolution; savannah theory fading
Brain expansion
DAVID: There are not enough fossils to answer all question, but brain shrinkage is accumpianed without skull case shrinkage.
dhw: Correct. So what makes you think that habilis and erectus began with “excess capacities”, as opposed to their having acquired new cells to meet new requirements when their existing capacity for complexification had been exhausted?
DAVID: Don't forget evolution is a process is which new processes build on earlier ones. Don't you think our brain is built from previous functioning brains, so why can't complexification be previously present?
You are repeating what I keep telling you! Previous brains complexified until their capacity for complexification could not cope with new requirements, and so they expanded. Ours followed the same process, but then it stopped expanding and complexification took over almost completely.
DAVID: I agree with your description of events but reject your intelligent cell theory.
dhw: So long as you agree with the theory that new cells were acquired when new conditions etc. demanded an increase in capacity, we can leave it open as to the nature of the mechanism. My objection is to your theory that new “excess” cells were acquired when they were not needed, purely in anticipation of future requirements that did not yet exist.
DAVID: A designer would logically design a brain for free usage which would implies shrinkage could occur as brain complexifies.
But past brains did not shrink, which implies that their powers of complexification had reached a limit, and so new cells were needed to cope with new requirements. Only in our case did the brain stop expanding.
dhw: […] you have not yet given us your own theory as to why our brain stopped expanding and reverted to enhanced complexification instead. Please tell us.
DAVID: You constantly fail to think as a designer would. God made our brain oversized so we could develop its use as we willed. Free will!!! It was so complete in its capacities further enlargement was never necessary. I view us as a finished endopint.
Why “oversized”? This is your theory that your God gave us “excess” cells, but a) they could hardly have been excessive if they served the purpose of giving us free will, and b) you have already agreed that habilis and erectus would also have had free will, i.e. WITHOUT those cells! But I can accept the logic that enhanced complexification made further expansion unnecessary, since that is clearly what happened. The question then is why and how cells became able to enhance their ability to complexify. Chicken and egg: were they forced to do so because further expansion would have presented problems, or did they do so spontaneously, thereby rendering expansion unnecessary? If your God intervened, as you believe, whichever answer you give will refute your claim that the extra cells were excessive, and one can only ask why he bothered with all the preceding stages of brain development if all he ever wanted was the brain we now have. But as you have told us repeatedly, you can’t find any reason for this, and it makes sense “only to God”. What WOULD explain the many stages is that your God gave cells the ability to design their own improvements - but you have closed your mind to this possibility,
Human evolution; new study says our brain did not shrink
QUOTE: "Multiple hypotheses on causes of reduction in modern human brain size need to be reassessed if human brains haven't actually changed in size since the arrival of our species."
DAVID: if true, this changes the whole tone of our discussion about modern humans. It means complexification occurs without shrinkage.
It makes no difference at all to the above arguments, but simply removes one area of discussion. We still have to explain why our brain stopped expanding.
Human evolution; savannah theory fading
by David Turell , Saturday, August 06, 2022, 17:38 (838 days ago) @ dhw
Brain expansion
DAVID: Don't forget evolution is a process is which new processes build on earlier ones. Don't you think our brain is built from previous functioning brains, so why can't complexification be previously present?
dhw: You are repeating what I keep telling you! Previous brains complexified until their capacity for complexification could not cope with new requirements, and so they expanded. Ours followed the same process, but then it stopped expanding and complexification took over almost completely.
All under God's designs.
DAVID: A designer would logically design a brain for free usage which would implies shrinkage could occur as brain complexifies.dhw: But past brains did not shrink, which implies that their powers of complexification had reached a limit, and so new cells were needed to cope with new requirements. Only in our case did the brain stop expanding.
Best explained as God's design. See new entry re a non-shrinkage theory.
dhw: […] you have not yet given us your own theory as to why our brain stopped expanding and reverted to enhanced complexification instead. Please tell us.DAVID: You constantly fail to think as a designer would. God made our brain oversized so we could develop its use as we willed. Free will!!! It was so complete in its capacities further enlargement was never necessary. I view us as a finished endpoint.
dhw: Why “oversized”? This is your theory that your God gave us “excess” cells, but a) they could hardly have been excessive if they served the purpose of giving us free will, and b) you have already agreed that habilis and erectus would also have had free will, i.e. WITHOUT those cells! But I can accept the logic that enhanced complexification made further expansion unnecessary, since that is clearly what happened.
We cannot tell from fossil brain pans whether excess neurons existed or not.
dhw: The question then is why and how cells became able to enhance their ability to complexify. Chicken and egg: were they forced to do so because further expansion would have presented problems, or did they do so spontaneously, thereby rendering expansion unnecessary? If your God intervened, as you believe, whichever answer you give will refute your claim that the extra cells were excessive, and one can only ask why he bothered with all the preceding stages of brain development if all he ever wanted was the brain we now have. But as you have told us repeatedly, you can’t find any reason for this, and it makes sense “only to God”. What WOULD explain the many stages is that your God gave cells the ability to design their own improvements - but you have closed your mind to this possibility,
I've not closed my mind to complexification in which cells design their own improvements.
Human evolution; new study says our brain did not shrink
QUOTE: "Multiple hypotheses on causes of reduction in modern human brain size need to be reassessed if human brains haven't actually changed in size since the arrival of our species."DAVID: if true, this changes the whole tone of our discussion about modern humans. It means complexification occurs without shrinkage.
dhw: It makes no difference at all to the above arguments, but simply removes one area of discussion. We still have to explain why our brain stopped expanding.
Easy to explain: God made it adequate for all our present and future needs. I remind you it arrived 315,000 years ago ready for full use as we desired to use it in our future. But you illogically deny it didn't arrive with overcapacity but enlarged to fill only new current requirements. One of your dodges.
Human evolution; savannah theory fading
Brain expansion
DAVID: Don't forget evolution is a process is which new processes build on earlier ones. Don't you think our brain is built from previous functioning brains, so why can't complexification be previously present?
dhw: You are repeating what I keep telling you! Previous brains complexified until their capacity for complexification could not cope with new requirements, and so they expanded. Ours followed the same process, but then it stopped expanding and complexification took over almost completely.
DAVID: All under God's designs.
What does that mean? In the past, you have agreed that the process of complexification works autonomously, without his intervention. Why should the process of expansion not have done the same? But I don’t have a problem with the theory that if God exists, he would have designed the mechanisms enabling cells to multiply and to complexify.
dhw: […] you have not yet given us your own theory as to why our brain stopped expanding and reverted to enhanced complexification instead. Please tell us.
DAVID: You constantly fail to think as a designer would. God made our brain oversized so we could develop its use as we willed. Free will!!! It was so complete in its capacities further enlargement was never necessary. I view us as a finished endpoint.
dhw: Why “oversized”? This is your theory that your God gave us “excess” cells, but a) they could hardly have been excessive if they served the purpose of giving us free will, and b) you have already agreed that habilis and erectus would also have had free will, i.e. WITHOUT those cells! But I can accept the logic that enhanced complexification made further expansion unnecessary, since that is clearly what happened.
DAVID: We cannot tell from fossil brain pans whether excess neurons existed or not.
That is not the point. If you say God gave us excess cells which resulted in our having free will, (a) the cells were NOT excessive, and (b) how could habilis and erectus have had free will without the new cells you say God gave us for that purpose?
dhw: The question then is why and how cells became able to enhance their ability to complexify. Chicken and egg: were they forced to do so because further expansion would have presented problems, or did they do so spontaneously, thereby rendering expansion unnecessary? If your God intervened, as you believe, whichever answer you give will refute your claim that the extra cells were excessive, and one can only ask why he bothered with all the preceding stages of brain development if all he ever wanted was the brain we now have. But as you have told us repeatedly, you can’t find any reason for this, and it makes sense “only to God”. What WOULD explain the many stages is that your God gave cells the ability to design their own improvements - but you have closed your mind to this possibility.
DAVID: I've not closed my mind to complexification in which cells design their own improvements.
As above, in the past, you have actually accepted that brain complexification was autonomous, but your beliefs seem to fluctuate. Even if you are now only open to that proposal, it’s a great boost to the theory that if God exists, he provided cells with the intelligence to “design their own improvements” throughout the history of evolution. Thank you.
Human evolution; new study says our brain did not shrink
DAVID: if true, this changes the whole tone of our discussion about modern humans. It means complexification occurs without shrinkage.
dhw: It makes no difference at all to the above arguments, but simply removes one area of discussion. We still have to explain why our brain stopped expanding.
DAVID: Easy to explain: God made it adequate for all our present and future needs. I remind you it arrived 315,000 years ago ready for full use as we desired to use it in our future. But you illogically deny it didn't arrive with overcapacity but enlarged to fill only new current requirements. One of your dodges.
Of course it didn’t arrive with overcapacity! Capacity relates to size (the number of cells). At all stages, the brain evolved by increasing its capacity as soon as its existing capacity proved inadequate to deal with new requirements. At each stage, it then complexified until once again it needed greater capacity (hence expansion). The same process went on until some new requirement once again resulted in the expansion to our current capacity. Then once again complexification took over (the capacity remained adequate) – but eventually, when new requirements arose, instead of increasing capacity (= expansion), the process of complexification was enhanced, thereby rendering further expansion unnecessary (but we don’t know why complexification took over from expansion). There was never any overcapacity at any stage, except possibly when our complexification process proved to be so efficient that cells which had previously been NECESSARY became redundant (hence shrinkage, though that is now being questioned).
Human evolution; savannah theory fading
by David Turell , Sunday, August 07, 2022, 20:43 (837 days ago) @ dhw
Brain expansion
dhw: You are repeating what I keep telling you! Previous brains complexified until their capacity for complexification could not cope with new requirements, and so they expanded. Ours followed the same process, but then it stopped expanding and complexification took over almost completely.
DAVID: All under God's designs.
dhw: What does that mean? In the past, you have agreed that the process of complexification works autonomously, without his intervention. Why should the process of expansion not have done the same? But I don’t have a problem with the theory that if God exists, he would have designed the mechanisms enabling cells to multiply and to complexify.
Fine
DAVID: We cannot tell from fossil brain pans whether excess neurons existed or not.dhw: That is not the point. If you say God gave us excess cells which resulted in our having free will, (a) the cells were NOT excessive, and (b) how could habilis and erectus have had free will without the new cells you say God gave us for that purpose?
Again, agree.
dhw: The question then is why and how cells became able to enhance their ability to complexify. Chicken and egg: were they forced to do so because further expansion would have presented problems, or did they do so spontaneously, thereby rendering expansion unnecessary? If your God intervened, as you believe, whichever answer you give will refute your claim that the extra cells were excessive, and one can only ask why he bothered with all the preceding stages of brain development if all he ever wanted was the brain we now have. But as you have told us repeatedly, you can’t find any reason for this, and it makes sense “only to God”. What WOULD explain the many stages is that your God gave cells the ability to design their own improvements - but you have closed your mind to this possibility.DAVID: I've not closed my mind to complexification in which cells design their own improvements.
dhw: As above, in the past, you have actually accepted that brain complexification was autonomous, but your beliefs seem to fluctuate. Even if you are now only open to that proposal, it’s a great boost to the theory that if God exists, he provided cells with the intelligence to “design their own improvements” throughout the history of evolution. Thank you.
Amazing, another agreement. God designed brains that could complexiify on their own. That doesn't mean He put in an expansion mechanism working on new designed larger brains without His full input of new design (dabble).
Human evolution; new study says our brain did not shrink
DAVID: if true, this changes the whole tone of our discussion about modern humans. It means complexification occurs without shrinkage.dhw: It makes no difference at all to the above arguments, but simply removes one area of discussion. We still have to explain why our brain stopped expanding.
DAVID: Easy to explain: God made it adequate for all our present and future needs. I remind you it arrived 315,000 years ago ready for full use as we desired to use it in our future. But you illogically deny it didn't arrive with overcapacity but enlarged to fill only new current requirements. One of your dodges.
dhw: Of course it didn’t arrive with overcapacity! Capacity relates to size (the number of cells). At all stages, the brain evolved by increasing its capacity as soon as its existing capacity proved inadequate to deal with new requirements. At each stage, it then complexified until once again it needed greater capacity (hence expansion). The same process went on until some new requirement once again resulted in the expansion to our current capacity. Then once again complexification took over (the capacity remained adequate) – but eventually, when new requirements arose, instead of increasing capacity (= expansion), the process of complexification was enhanced,
How did the 'enhancing' happen: by chance, by cell committees, or by God's design?
dhw: thereby rendering further expansion unnecessary (but we don’t know why complexification took over from expansion). There was never any overcapacity at any stage, except possibly when our complexification process proved to be so efficient that cells which had previously been NECESSARY became redundant (hence shrinkage, though that is now being questioned).
How about God designed it big enough for all future needs? What our brain has done factually shows exactly that either from God or chance or cell committees.
Human evolution; savannah theory fading
Brain expansion
dhw: I don’t have a problem with the theory that if God exists, he would have designed the mechanisms enabling cells to multiply and to complexify.
DAVID: Fine
dhw: That is not the point. If you say God gave us excess cells which resulted in our having free will, (a) the cells were NOT excessive, and (b) how could habilis and erectus have had free will without the new cells you say God gave us for that purpose?
DAVID: Again, agree.
DAVID: I've not closed my mind to complexification in which cells design their own improvements.
dhw: Even if you are now only open to that proposal, it’s a great boost to the theory that if God exists, he provided cells with the intelligence to “design their own improvements” throughout the history of evolution. Thank you.
DAVID: Amazing, another agreement. God designed brains that could complexiify on their own. That doesn't mean He put in an expansion mechanism working on new designed larger brains without His full input of new design (dabble).
After all these delightful agreements, you proceed to muddy the waters with an incomprehensible post. You have agreed that he could have designed the mechanisms for complexification and expansion (= cells multiplying), so how does the mechanism for expansion “work on new designed larger brains”? The mechanism for expansion produces the larger brain when complexification can no longer cope with new requirements. The new cells meet the new requirements. So what “new design” are you talking about that requires your God’s full input, if he has already designed the mechanisms for complexification and expansion?
Human evolution; new study says our brain did not shrink
dhw: We still have to explain why our brain stopped expanding.
DAVID: Easy to explain: God made it adequate for all our present and future needs. I remind you it arrived 315,000 years ago ready for full use as we desired to use it in our future. But you illogically deny it didn't arrive with overcapacity but enlarged to fill only new current requirements.bbb One of your dodges.
dhw: Of course it didn’t arrive with overcapacity! Capacity relates to size (the number of cells). At all stages, the brain evolved by increasing its capacity as soon as its existing capacity proved inadequate to deal with new requirements. At each stage, it then complexified until once again it needed greater capacity (hence expansion). The same process went on until some new requirement once again resulted in the expansion to our current capacity. Then once again complexification took over (the capacity remained adequate) – but eventually, when new requirements arose, instead of increasing capacity (= expansion), the process of complexification was enhanced,
DAVID: How did the 'enhancing' happen: by chance, by cell committees, or by God's design?
If God exists, and if he designed an autonomous mechanism for cells to do their own complexification – as you have agreed above – then it’s only logical that the cells themselves would have done the enhancing, just as they would previously have organized their own multiplication.
dhw: […] thereby rendering further expansion unnecessary (but we don’t know why complexification took over from expansion). There was never any overcapacity at any stage, except possibly when our complexification process proved to be so efficient that cells which had previously been NECESSARY became redundant (hence shrinkage, though that is now being questioned).
DAVID: How about God designed it big enough for all future needs? What our brain has done factually shows exactly that either from God or chance or cell committees.
Thank you for quietly dropping your attack on me for rejecting your theory of “overcapacity”. You are obviously right to say that our brain is big enough for our needs, since it hasn’t expanded. I don’t know why you think your God has to intervene in order to specially design our brain, since you accept that he had already set up the mechanisms for expansion and complexification for all the earlier brains. But I guess this lies at the heart of all your theories: even though you have now opened your mind to the possibility that “cells design their own improvements”, you still want your God to design every improvement himself!
Human evolution; savannah theory fading
by David Turell , Monday, August 08, 2022, 15:47 (836 days ago) @ dhw
Brain expansion
DAVID: I've not closed my mind to complexification in which cells design their own improvements.
dhw: Even if you are now only open to that proposal, it’s a great boost to the theory that if God exists, he provided cells with the intelligence to “design their own improvements” throughout the history of evolution. Thank you.
DAVID: Amazing, another agreement. God designed brains that could complexiify on their own. That doesn't mean He put in an expansion mechanism working on new designed larger brains without His full input of new design (dabble).
dhw: After all these delightful agreements, you proceed to muddy the waters with an incomprehensible post. You have agreed that he could have designed the mechanisms for complexification and expansion (= cells multiplying), so how does the mechanism for expansion “work on new designed larger brains”? The mechanism for expansion produces the larger brain when complexification can no longer cope with new requirements. The new cells meet the new requirements. So what “new design” are you talking about that requires your God’s full input, if he has already designed the mechanisms for complexification and expansion?
Yes, complexification is a God-given built-in system. Larger, better brains are by God's design, not cell committees. Still my position. The cell committees know how to complexify, nothing more.
Human evolution; new study says our brain did not shrinkdhw: Of course it didn’t arrive with overcapacity! Capacity relates to size (the number of cells). At all stages, the brain evolved by increasing its capacity as soon as its existing capacity proved inadequate to deal with new requirements. At each stage, it then complexified until once again it needed greater capacity (hence expansion). The same process went on until some new requirement once again resulted in the expansion to our current capacity. Then once again complexification took over (the capacity remained adequate) – but eventually, when new requirements arose, instead of increasing capacity (= expansion), the process of complexification was enhanced,
DAVID: How did the 'enhancing' happen: by chance, by cell committees, or by God's design?
dhw: If God exists, and if he designed an autonomous mechanism for cells to do their own complexification – as you have agreed above – then it’s only logical that the cells themselves would have done the enhancing, just as they would previously have organized their own multiplication.
Same old secondhand design. C ells are not intelligent enough to design future forms.
dhw: […] thereby rendering further expansion unnecessary (but we don’t know why complexification took over from expansion). There was never any overcapacity at any stage, except possibly when our complexification process proved to be so efficient that cells which had previously been NECESSARY became redundant (hence shrinkage, though that is now being questioned).DAVID: How about God designed it big enough for all future needs? What our brain has done factually shows exactly that either from God or chance or cell committees.
dhw: Thank you for quietly dropping your attack on me for rejecting your theory of “overcapacity”. You are obviously right to say that our brain is big enough for our needs, since it hasn’t expanded. I don’t know why you think your God has to intervene in order to specially design our brain, since you accept that he had already set up the mechanisms for expansion and complexification for all the earlier brains. But I guess this lies at the heart of all your theories: even though you have now opened your mind to the possibility that “cells design their own improvements”, you still want your God to design every improvement himself!
God designed all previous hominin/homo brains. I've never changed that opinion. I've agreed from above: "The cell committees know how to complexify, nothing more".
Human evolution; savannah theory fading
Brain expansion
DAVID: I've not closed my mind to complexification in which cells design their own improvements.
dhw: Even if you are now only open to that proposal, it’s a great boost to the theory that if God exists, he provided cells with the intelligence to “design their own improvements” throughout the history of evolution. Thank you.
DAVID: Amazing, another agreement. God designed brains that could complexiify on their own. That doesn't mean He put in an expansion mechanism working on new designed larger brains without His full input of new design (dabble).
dhw: After all these delightful agreements, you proceed to muddy the waters with an incomprehensible post. You have agreed that he could have designed the mechanisms for complexification and expansion (= cells multiplying), so how does the mechanism for expansion “work on new designed larger brains”? The mechanism for expansion produces the larger brain when complexification can no longer cope with new requirements. The new cells meet the new requirements. So what “new design” are you talking about that requires your God’s full input, if he has already designed the mechanisms for complexification and expansion?
DAVID: Yes, complexification is a God-given built-in system. Larger, better brains are by God's design, not cell committees. […] The cell committees know how to complexify, nothing more.
You accept the possibility that cell communities are able to produce “better” brains through their autonomous intelligence (to “design their own improvements”), but are you now doing a volte face on your agreement that if your God exists, he would have “designed the mechanisms enabling cells to multiply and to complexify”? Why do you think autonomous multiplying is beyond the capability of cell communities which can autonomously design their own improvements?
Human evolution; new study says our brain did not shrink
dhw: Of course it didn’t arrive with overcapacity! Capacity relates to size (the number of cells). At all stages, the brain evolved by increasing its capacity as soon as its existing capacity proved inadequate to deal with new requirements. At each stage, it then complexified until once again it needed greater capacity (hence expansion). The same process went on until some new requirement once again resulted in the expansion to our current capacity. Then once again complexification took over (the capacity remained adequate) – but eventually, when new requirements arose, instead of increasing capacity (= expansion), the process of complexification was enhanced,
DAVID: How did the 'enhancing' happen: by chance, by cell committees, or by God's design?
dhw: If God exists, and if he designed an autonomous mechanism for cells to do their own complexification – as you have agreed above – then it’s only logical that the cells themselves would have done the enhancing, just as they would previously have organized their own multiplication.
DAVID: Same old secondhand design. Cells are not intelligent enough to design future forms.
The theory is that cells design forms in response to present requirements, not in anticipation of conditions that do not yet exist. You wrote – quoted above – “I've not closed my mind to complexification in which cells design their own improvements.” Don’t you think enhancement means improvement?
DAVID: How about God designed it big enough for all future needs? What our brain has done factually shows exactly that either from God or chance or cell committees.
dhw: Thank you for quietly dropping your attack on me for rejecting your theory of “overcapacity”. You are obviously right to say that our brain is big enough for our needs, since it hasn’t expanded. I don’t know why you think your God has to intervene in order to specially design our brain, since you accept that he had already set up the mechanisms for expansion and complexification for all the earlier brains. But I guess this lies at the heart of all your theories: even though you have now opened your mind to the possibility that “cells design their own improvements”, you still want your God to design every improvement himself!
DAVID: God designed all previous hominin/homo brains. I've never changed that opinion. I've agreed from above: "The cell committees know how to complexify, nothing more".
Please tell us what else he designed, once he had designed “the mechanisms enabling cells to multiply and to complexify” – which we have agreed were already present in previous hominin/homo brains?
Human evolution; savannah theory fading
by David Turell , Tuesday, August 09, 2022, 16:57 (835 days ago) @ dhw
Brain expansion
DAVID: Yes, complexification is a God-given built-in system. Larger, better brains are by God's design, not cell committees. […] The cell committees know how to complexify, nothing more.
dhw: You accept the possibility that cell communities are able to produce “better” brains through their autonomous intelligence (to “design their own improvements”), but are you now doing a volte face on your agreement that if your God exists, he would have “designed the mechanisms enabling cells to multiply and to complexify”? Why do you think autonomous multiplying is beyond the capability of cell communities which can autonomously design their own improvements?
I have not agreed to anything more than complexification improves brain function as an improvement within the same original brain, and complexification is a process God designed into the brain cells
Human evolution; new study says our brain did not shrinkdhw: If God exists, and if he designed an autonomous mechanism for cells to do their own complexification – as you have agreed above – then it’s only logical that the cells themselves would have done the enhancing, just as they would previously have organized their own multiplication.
DAVID: Same old secondhand design. Cells are not intelligent enough to design future forms.
dhw: The theory is that cells design forms in response to present requirements, not in anticipation of conditions that do not yet exist. You wrote – quoted above – “I've not closed my mind to complexification in which cells design their own improvements.” Don’t you think enhancement means improvement?
To repeat: " I have not agreed to anything more than complexification improves brain function as an improvement within the same original brain, and complexification is a process God designed into the brain cells." I am sure our original sapiens brain has been shaped by complexification to be an improved current brain.
DAVID: How about God designed it big enough for all future needs? What our brain has done factually shows exactly that either from God or chance or cell committees.dhw: Thank you for quietly dropping your attack on me for rejecting your theory of “overcapacity”. You are obviously right to say that our brain is big enough for our needs, since it hasn’t expanded. I don’t know why you think your God has to intervene in order to specially design our brain, since you accept that he had already set up the mechanisms for expansion and complexification for all the earlier brains. But I guess this lies at the heart of all your theories: even though you have now opened your mind to the possibility that “cells design their own improvements”, you still want your God to design every improvement himself!
DAVID: God designed all previous hominin/homo brains. I've never changed that opinion. I've agreed from above: "The cell committees know how to complexify, nothing more".
dhw: Please tell us what else he designed, once he had designed “the mechanisms enabling cells to multiply and to complexify” – which we have agreed were already present in previous hominin/homo brains?
Answered above. What does 'please tell us what else He deigned' ask? My answer is everything.
Human evolution; savannah theory fading
Brain expansion
DAVID: Yes, complexification is a God-given built-in system. Larger, better brains are by God's design, not cell committees. […] The cell committees know how to complexify, nothing more.
dhw: You accept the possibility that cell communities are able to produce “better” brains through their autonomous intelligence (to “design their own improvements”), but are you now doing a volte face on your agreement that if your God exists, he would have “designed the mechanisms enabling cells to multiply and to complexify”? Why do you think autonomous multiplying is beyond the capability of cell communities which can autonomously design their own improvements?
DAVID: I have not agreed to anything more than complexification improves brain function as an improvement within the same original brain, and complexification is a process God designed into the brain cells.
I will of course accept that when you said “Fine” in response to the quote I’ve bolded above, it was a slip of your pen. However, you have definitely accepted that your God (if he exists) would have designed the complexification process which autonomously (i.e. without his intervention) enables cells to design their own improvements. So please tell me why you think he could not have designed an autonomous mechanism enabling cells to add to their numbers when necessary.
DAVID: How did the enhancement happen? […]
dhw: If God exists, and if he designed an autonomous mechanism for cells to do their own complexification […] then it’s only logical that the cells themselves would have done the enhancing.
DAVID: Cells are not intelligent enough to design future forms.
dhw: The theory is that cells design forms in response to present requirements, not in anticipation of conditions that do not yet exist. You wrote – quoted above – “I've not closed my mind to complexification in which cells design their own improvements.” Don’t you think enhancement means improvement?
DAVID: To repeat: "I have not agreed to anything more than complexification improves brain function as an improvement within the same original brain, and complexification is a process God designed into the brain cells." I am sure our original sapiens brain has been shaped by complexification to be an improved current brain.
Agreed (if God exists). So now you accept that the enhancement would have been done by the cells themselves, unless for some reason you think enhancement does not mean improvement.
DAVID: God designed all previous hominin/homo brains. I've never changed that opinion. I've agreed from above: "The cell committees know how to complexify, nothing more".
dhw: Please tell us what else he designed, once he had designed “the mechanisms enabling cells to multiply and to complexify” – which we have agreed were already present in previous hominin/homo brains?
DAVID: Answered above. What does 'please tell us what else He deigned' ask? My answer is everything.
Sorry, I was referring only to brains. We now have him designing a mechanism for complexification. The improvements are carried out autonomously by the cells themselves. So when you say “God designed all previous hominin/homo brains”, what else do you think he designed apart from the mechanisms for complexification (which is autonomous) and expansion (which you say he engineered individually, but which I propose would also have been autonomous). My point is that these mechanisms would have been there from the earliest hominin/homo brain onwards, in which case the improvements from the very first brain onwards would have been made autonomously by the cells themselves. Even if he individually inserted each set of additional cells, they would still have created improvements through the autonomous process of complexification. So what was left for him to “design”?
Human evolution; savannah theory fading
by David Turell , Wednesday, August 10, 2022, 20:23 (834 days ago) @ dhw
edited by David Turell, Wednesday, August 10, 2022, 20:44
Brain expansion
DAVID: I have not agreed to anything more than complexification improves brain function as an improvement within the same original brain, and complexification is a process God designed into the brain cells.
dhw: I will of course accept that when you said “Fine” in response to the quote I’ve bolded above, it was a slip of your pen. However, you have definitely accepted that your God (if he exists) would have designed the complexification process which autonomously (i.e. without his intervention) enables cells to design their own improvements. So please tell me why you think he could not have designed an autonomous mechanism enabling cells to add to their numbers when necessary.
I view complexification as a requirement to allow the individual to use his brain and develop the proper neurologic networks to support new uses, but it does not apply to new neurons appearing except in the hippocampus. This is all fact. We have to accept what God provided. No cell or committee of them knows how to design a new step. It is your theory, nothing more.
dhw: The theory is that cells design forms in response to present requirements, not in anticipation of conditions that do not yet exist. You wrote – quoted above – “I've not closed my mind to complexification in which cells design their own improvements.” Don’t you think enhancement means improvement?
No, it means new networks for new uses with existing neurons which is an obvious improvement
DAVID: To repeat: "I have not agreed to anything more than complexification improves brain function as an improvement within the same original brain, and complexification is a process God designed into the brain cells." I am sure our original sapiens brain has been shaped by complexification to be an improved current brain.dhw: Agreed (if God exists). So now you accept that the enhancement would have been done by the cells themselves, unless for some reason you think enhancement does not mean improvement.
Yes, a new complexification is an enhancement and an improvement in function.
DAVID: God designed all previous hominin/homo brains. I've never changed that opinion. I've agreed from above: "The cell committees know how to complexify, nothing more".dhw: Please tell us what else he designed, once he had designed “the mechanisms enabling cells to multiply and to complexify” – which we have agreed were already present in previous hominin/homo brains?
Based on our current brain new neurons are limited to the hippocampus and I must assume previous brains had the same arrangement
DAVID: Answered above. What does 'please tell us what else He deigned' ask? My answer is everything.dhw: Sorry, I was referring only to brains. We now have him designing a mechanism for complexification. The improvements are carried out autonomously by the cells themselves. So when you say “God designed all previous hominin/homo brains”, what else do you think he designed apart from the mechanisms for complexification (which is autonomous) and expansion (which you say he engineered individually, but which I propose would also have been autonomous). My point is that these mechanisms would have been there from the earliest hominin/homo brain onwards, in which case the improvements from the very first brain onwards would have been made autonomously by the cells themselves. Even if he individually inserted each set of additional cells, they would still have created improvements through the autonomous process of complexification. So what was left for him to “design”?
He must design the enlargement of skull brain pan and enlargement of the new bigger brain with more neurons, with which complexification could work to handle new activities, etc. And obviously design the right sized pelvis for mommy to handle the bigger sized baby skull.
Let's imagine your theory: new neurons increase very slowly, gradually creating pressure on the skull cells, which then respond to enlarge the brain pan. Our fossil collection is to sparce to prove this, but we shall accept the possibility. The big problem is who tells mommy's pelvis to enlarge? Your previous answers have been let them die until they figure it out. Now let's assume the fossil record tells the truth and brain size actually jumped 100cc or more at a time. This is not gradual. Does mommy still figure it out by dying? Oh, I forgot, Daddy's cells signal his wife's cells to get with it. I'll stay with God designing all.
Human evolution; savannah theory fading
Brain expansion
dhw: […] you have definitely accepted that your God (if he exists) would have designed the complexification process which autonomously (i.e. without his intervention) enables cells to design their own improvements. So please tell me why you think he could not have designed an autonomous mechanism enabling cells to add to their numbers when necessary.
DAVID: I view complexification as a requirement to allow the individual to use his brain and develop the proper neurologic networks to support new uses, but it does not apply to new neurons appearing except in the hippocampus. This is all fact. We have to accept what God provided. No cell or committee of them knows how to design a new step. It is your theory, nothing more.
Yes, it is a fact that we use our brains, and you have accepted that the complexification mechanism through which “cells design their own improvements”, is autonomous – i.e. God does not pop in every time a new step results in complexification. Don’t you think new steps are an improvement? Now please tell us why you think that although your God created the mechanism enabling cells to complexify autonomously, he could not possibly have created the mechanism enabling them to add to their number.
dhw: Don’t you think enhancement means improvement?
DAVID: No, it means new networks for new uses with existing neurons which is an obvious improvement.
Enhancement means new networks for new uses with existing neurons which is an obvious improvement, but apparently that means it is not an improvement.
dhw: We now have him designing a mechanism for complexification. The improvements are carried out autonomously by the cells themselves. So when you say “God designed all previous hominin/homo brains”, what else do you think he designed apart from the mechanisms for complexification (which is autonomous) and expansion (which you say he engineered individually, but which I propose would also have been autonomous). My point is that these mechanisms would have been there from the earliest hominin/homo brain onwards, in which case the improvements from the very first brain onwards would have been made autonomously by the cells themselves. Even if he individually inserted each set of additional cells, they would still have created improvements through the autonomous process of complexification. So what was left for him to “design”?
DAVID: He must design the enlargement of skull brain pan and enlargement of the new bigger brain with more neurons, with which complexification could work to handle new activities, etc.
That is the mechanism for enlargement/expansion!
DAVID: And obviously design the right sized pelvis for mommy to handle the bigger sized baby skull.
We have already switched from the savannah theory to brain expansion, and now you want to switch to the pelvis. We’ve been over that problem. Please stick to the subject. You keep harping on about God designing all previous brains (as well as our own), and I am asking what part of each new brain he designed, apart from the mechanisms for enlargement and complexification – the latter being autonomously responsible for improvements.
Human evolution; savannah theory fading
by David Turell , Thursday, August 11, 2022, 17:22 (833 days ago) @ dhw
Brain expansion
dhw: […] you have definitely accepted that your God (if he exists) would have designed the complexification process which autonomously (i.e. without his intervention) enables cells to design their own improvements. So please tell me why you think he could not have designed an autonomous mechanism enabling cells to add to their numbers when necessary.
DAVID: I view complexification as a requirement to allow the individual to use his brain and develop the proper neurologic networks to support new uses, but it does not apply to new neurons appearing except in the hippocampus. This is all fact. We have to accept what God provided. No cell or committee of them knows how to design a new step. It is your theory, nothing more.
dhw: Yes, it is a fact that we use our brains, and you have accepted that the complexification mechanism through which “cells design their own improvements”, is autonomous – i.e. God does not pop in every time a new step results in complexification. Don’t you think new steps are an improvement? Now please tell us why you think that although your God created the mechanism enabling cells to complexify autonomously, he could not possibly have created the mechanism enabling them to add to their number.
He gave cells that ability confined to the hippocampus. Obviously that is all He wanted to do.
dhw: Don’t you think enhancement means improvement?DAVID: No, it means new networks for new uses with existing neurons which is an obvious improvement.
dhw: Enhancement means new networks for new uses with existing neurons which is an obvious improvement, but apparently that means it is not an improvement.
I've just agreed, as above. What is your misinterpretation? New networks are an improvement.
dhw: We now have him designing a mechanism for complexification. The improvements are carried out autonomously by the cells themselves. So when you say “God designed all previous hominin/homo brains”, what else do you think he designed apart from the mechanisms for complexification (which is autonomous) and expansion (which you say he engineered individually, but which I propose would also have been autonomous). My point is that these mechanisms would have been there from the earliest hominin/homo brain onwards, in which case the improvements from the very first brain onwards would have been made autonomously by the cells themselves. Even if he individually inserted each set of additional cells, they would still have created improvements through the autonomous process of complexification. So what was left for him to “design”?DAVID: He must design the enlargement of skull brain pan and enlargement of the new bigger brain with more neurons, with which complexification could work to handle new activities, etc.
That is the mechanism for enlargement/expansion!
DAVID: And obviously design the right sized pelvis for mommy to handle the bigger sized baby skull.
dhw: We have already switched from the savannah theory to brain expansion, and now you want to switch to the pelvis. We’ve been over that problem. Please stick to the subject. You keep harping on about God designing all previous brains (as well as our own), and I am asking what part of each new brain he designed, apart from the mechanisms for enlargement and complexification – the latter being autonomously responsible for improvements.
You know the answer: the key enlargements were frontal and prefrontal cortex which were given the ability for complexification. And you have offered no answer for the pelvic problem as bfore.
Human evolution; special losses allowing our vocalization
by David Turell , Thursday, August 11, 2022, 23:11 (833 days ago) @ David Turell
edited by David Turell, Thursday, August 11, 2022, 23:20
New comparison discovery :
https://www.sciencenews.org/article/humans-primates-voice-control-cords-larynx-membrane
"A crying baby, a screaming adult, a teenager whose voice cracks — people could have sounded this shrill all the time, a new study suggests, if not for a crucial step in human evolution.
"It’s what we’re missing that makes the difference. Humans have vocal cords, muscles in our larynx, or voice box, that vibrate to produce sound (SN: 11/18/15). But unlike all other studied primates, humans don’t have small bits of tissue above the vocal cords called vocal membranes. That uniquely human trait helps people control their voices well enough to produce the sounds that are the building blocks of spoken language, researchers report in the Aug. 12 Science.
"Vocal membranes act like a reed in a clarinet, making it easier for some animals to shout loud and shrill. Think of the piercing calls of howler monkeys (SN: 10/22/15). When researchers used MRI and CT scans to look for vocal membranes in 43 different primate species, the scientists were surprised by what they saw: All primates except humans had the tissue.
***
"In both experiments, the larynges made sounds that would often fluctuate wildly in pitch. Nishimura’s team found that happens only when an animal has both vocal membranes and vocal cords.
***
"Since humans don’t have vocal membranes, we usually make more stable sounds than other primates, the team concludes. Our mouths and tongues, the idea goes, can then manipulate those stable tones into the complex sounds that language is based on.
“That’s a really elegant explanation,” says Sue Anne Zollinger, an animal physiologist at Manchester Metropolitan University in England who was not involved in the study. It’s almost counterintuitive, she says: “You lose complexity to be able to produce more complex sounds.”
"The loss of vocal membranes isn’t the only thing that makes humans more eloquent than other primates. Beyond anatomical differences, humans have specific genes that may have helped drive language evolution (SN: 8/3/18). And perhaps most importantly, human brains are structured differently from other primates in ways that also give us more control over our speech."
Comment: all those changes in loss of membrane and developing a specialized type of brain that can handle the development of language sounds like purposeful design in advance of n
need/use. I might add our closest relatives, apes and monkeys survive perfectly sell with their rudimentary communication. So, what survival need made the changes appear in a naturally functioning evolutionary process? I see none.
Human evolution; savannah theory fading
Brain expansion
dhw: […] you have accepted that the complexification mechanism through which “cells design their own improvements”, is autonomous – i.e. God does not pop in every time a new step results in complexification. Don’t you think new steps are an improvement? Now please tell us why you think that although your God created the mechanism enabling cells to complexify autonomously, he could not possibly have created the mechanism enabling them to add to their number.
DAVID: He gave cells that ability confined to the hippocampus. Obviously that is all He wanted to do.
I don’t understand. Are you saying that the hippocampus cells of all our ancestors had the autonomous ability to add to their numbers, but all other additional brain cells had to be designed and provided by your God?
dhw: Don’t you think enhancement means improvement?
DAVID: No, it means new networks for new uses with existing neurons which is an obvious improvement.
dhw: Enhancement means new networks for new uses with existing neurons which is an obvious improvement, but apparently that means it is not an improvement.
DAVID: I've just agreed, as above. What is your misinterpretation? New networks are an improvement.
So why did you say no? (Bolded)
dhw: My point is that these mechanisms [for complexification and expansion/enlargement] would have been there from the earliest hominin/homo brain onwards, in which case the improvements from the very first brain onwards would have been made autonomously by the cells themselves. Even if he individually inserted each set of additional cells, they would still have created improvements through the autonomous process of complexification. So what was left for him to “design”?
DAVID: He must design the enlargement of skull brain pan and enlargement of the new bigger brain with more neurons, with which complexification could work to handle new activities, etc.
dhw: That is the mechanism for enlargement/expansion!
DAVID: And obviously design the right sized pelvis for mommy to handle the bigger sized baby skull.
dhw: We have already switched from the savannah theory to brain expansion, and now you want to switch to the pelvis. We’ve been over that problem. Please stick to the subject. You keep harping on about God designing all previous brains (as well as our own), and I am asking what part of each new brain he designed, apart from the mechanisms for enlargement and complexification – the latter being autonomously responsible for improvements.
DAVID: You know the answer: the key enlargements were frontal and prefrontal cortex which were given the ability for complexification.
You have agreed that the ability for complexification was present in all early brains, and enlargement is enlargement, no matter which section of the brain is enlarged! Are you now saying that your God had to specially design all the cells that were added to earlier cortices and give them a special new ability for complexification?
DAVID: And you have offered no answer for the pelvic problem as before.
I asked about special designs for the brain other than the mechanisms for complexification and enlargement. It seems that you can’t think of any, and so you are trying to change the subject, which is the dodging tactic you keep using during our discussions of your illogical theories of evolution. You know my theory concerning the “pelvic problem”, which is precisely the same as my theory about all the problems posed to all species by changing conditions: intelligent cell communities learn to adapt. No doubt there would have been many instances of death in childbirth until those pelvises which adapted to the new requirements became the norm.
Human evolution; savannah theory fading
by David Turell , Friday, August 12, 2022, 18:33 (832 days ago) @ dhw
Brain expansion
dhw: Don’t you think enhancement means improvement?
DAVID: No, it means new networks for new uses with existing neurons which is an obvious improvement.
dhw: Enhancement means new networks for new uses with existing neurons which is an obvious improvement, but apparently that means it is not an improvement.
DAVID: I've just agreed, as above. What is your misinterpretation? New networks are an improvement.
dhw: So why did you say no? (Bolded)
The problem is my interpretation that by improvement you implied enlargements. It seems you didn't.
dhw: We have already switched from the savannah theory to brain expansion, and now you want to switch to the pelvis. We’ve been over that problem. Please stick to the subject. You keep harping on about God designing all previous brains (as well as our own), and I am asking what part of each new brain he designed, apart from the mechanisms for enlargement and complexification – the latter being autonomously responsible for improvements.DAVID: You know the answer: the key enlargements were frontal and prefrontal cortex which were given the ability for complexification.
dhw: You have agreed that the ability for complexification was present in all early brains, and enlargement is enlargement, no matter which section of the brain is enlarged! Are you now saying that your God had to specially design all the cells that were added to earlier cortices and give them a special new ability for complexification?
Of course.
DAVID: And you have offered no answer for the pelvic problem as before.dhw: I asked about special designs for the brain other than the mechanisms for complexification and enlargement. It seems that you can’t think of any, and so you are trying to change the subject, which is the dodging tactic you keep using during our discussions of your illogical theories of evolution. You know my theory concerning the “pelvic problem”, which is precisely the same as my theory about all the problems posed to all species by changing conditions: intelligent cell communities learn to adapt. No doubt there would have been many instances of death in childbirth until those pelvises which adapted to the new requirements became the norm.
Or in my view, God arranged it so new heads fit into new sized brains all at once, without all those messy deaths you prescribe. God's designs are gentler than your natural approach
Human evolution; savannah theory fading
Brain expansion
dhw: You keep harping on about God designing all previous brains (as well as our own), and I am asking what part of each new brain he designed, apart from the mechanisms for enlargement and complexification – the latter being autonomously responsible for improvements.
DAVID: You know the answer: the key enlargements were frontal and prefrontal cortex which were given the ability for complexification.
dhw: You have agreed that the ability for complexification was present in all early brains, and enlargement is enlargement, no matter which section of the brain is enlarged! Are you now saying that your God had to specially design all the cells that were added to earlier cortices and give them a special new ability for complexification?
DAVID: Of course.
But I thought you agreed that earlier brain cells already had the autonomous ability to complexify. So when God operated on all these sleeping homos, he added the new cortex cells to the old ones, and separately designed the same ability to complexify as that of the existing cortex cells. Wouldn’t it have been a lot simpler if he’d just given all the complexifying cells the ability to add to their number when they needed to?
DAVID: And you have offered no answer for the pelvic problem as before.
dhw: I asked about special designs for the brain other than the mechanisms for complexification and enlargement. It seems that you can’t think of any, and so you are trying to change the subject, which is the dodging tactic you keep using during our discussions of your illogical theories of evolution. You know my theory concerning the “pelvic problem”, which is precisely the same as my theory about all the problems posed to all species by changing conditions: intelligent cell communities learn to adapt. No doubt there would have been many instances of death in childbirth until those pelvises which adapted to the new requirements became the norm.
DAVID: Or in my view, God arranged it so new heads fit into new sized brains all at once, without all those messy deaths you prescribe. God's designs are gentler than your natural approach.
I have given you the same answer I gave you before, but if you prefer your own theory that your God preprogrammed bigger heads and pelvises 3.8 billion years ago, or performed operations on all those women’s pelvises, that’s fine. Death in childbirth wasn’t all that uncommon in historic times, so it’s perfectly conceivable that such a problem would have caused more deaths in pre-historic times.
Human evolution; savannah theory fading
by David Turell , Saturday, August 13, 2022, 21:02 (831 days ago) @ dhw
Brain expansion
dhw: You have agreed that the ability for complexification was present in all early brains, and enlargement is enlargement, no matter which section of the brain is enlarged! Are you now saying that your God had to specially design all the cells that were added to earlier cortices and give them a special new ability for complexification?
DAVID: Of course.
dhw: But I thought you agreed that earlier brain cells already had the autonomous ability to complexify. So when God operated on all these sleeping homos, he added the new cortex cells to the old ones, and separately designed the same ability to complexify as that of the existing cortex cells. Wouldn’t it have been a lot simpler if he’d just given all the complexifying cells the ability to add to their number when they needed to?
Remember He specifically did in the hippocampus. If that ability is not elsewhere, that was His choice and answers your question.
DAVID: And you have offered no answer for the pelvic problem as before.dhw: I asked about special designs for the brain other than the mechanisms for complexification and enlargement. It seems that you can’t think of any, and so you are trying to change the subject, which is the dodging tactic you keep using during our discussions of your illogical theories of evolution. You know my theory concerning the “pelvic problem”, which is precisely the same as my theory about all the problems posed to all species by changing conditions: intelligent cell communities learn to adapt. No doubt there would have been many instances of death in childbirth until those pelvises which adapted to the new requirements became the norm.
DAVID: Or in my view, God arranged it so new heads fit into new sized brains all at once, without all those messy deaths you prescribe. God's designs are gentler than your natural approach.
dhw: I have given you the same answer I gave you before, but if you prefer your own theory that your God preprogrammed bigger heads and pelvises 3.8 billion years ago, or performed operations on all those women’s pelvises, that’s fine. Death in childbirth wasn’t all that uncommon in historic times, so it’s perfectly conceivable that such a problem would have caused more deaths in pre-historic times.
You are very uncaring for our ancestors.
Human evolution; savannah theory fading
Brain expansion
dhw: You have agreed that the ability for complexification was present in all early brains, and enlargement is enlargement, no matter which section of the brain is enlarged! Are you now saying that your God had to specially design all the cells that were added to earlier cortices and give them a special new ability for complexification?
DAVID: Of course.
dhw: But I thought you agreed that earlier brain cells already had the autonomous ability to complexify. So when God operated on all these sleeping homos, he added the new cortex cells to the old ones, and separately designed the same ability to complexify as that of the existing cortex cells. Wouldn’t it have been a lot simpler if he’d just given all the complexifying cells the ability to add to their number when they needed to?
DAVID: Remember He specifically did in the hippocampus. If that ability is not elsewhere, that was His choice and answers your question.
It shows that the cells are capable of adding to their number! And so there is no reason to suppose that the same ability was NOT present in other parts of our ancestors’ brains, but when it came to us, complexification took over. We don’t know why the human brain stopped expanding. You reject the idea that it might have caused anatomical problems, but you have not provided any other explanation. You simply agree that the autonomous mechanism for complexification took over. Once more: if you believe your God gave past and present cells the autonomous ability to complexify, why do you regard it as impossible for him to have given all of them the autonomous ability to add to their number (as shown by the modern hippocampus)?
DAVID: And you have offered no answer for the pelvic problem as before.
dhw: I have given you the same answer I gave you before, but if you prefer your own theory that your God preprogrammed bigger heads and pelvises 3.8 billion years ago, or performed operations on all those women’s pelvises, that’s fine. Death in childbirth wasn’t all that uncommon in historic times, so it’s perfectly conceivable that such a problem would have caused more deaths in pre-historic times.
DAVID: You are very uncaring for our ancestors.
This has nothing to do with me “caring”! With your doctor’s knowledge of all the problems relating to childbirth, why are you so certain that our ancestors had no problems and God “arranged it so new heads fit into new sized brains all at once”? Has he been so uncaring for all those sapiens mums who never made it?
Human evolution; savannah theory fading
by David Turell , Sunday, August 14, 2022, 16:12 (830 days ago) @ dhw
Brain expansion
dhw: You have agreed that the ability for complexification was present in all early brains, and enlargement is enlargement, no matter which section of the brain is enlarged! Are you now saying that your God had to specially design all the cells that were added to earlier cortices and give them a special new ability for complexification?
DAVID: Of course.
dhw: But I thought you agreed that earlier brain cells already had the autonomous ability to complexify. So when God operated on all these sleeping homos, he added the new cortex cells to the old ones, and separately designed the same ability to complexify as that of the existing cortex cells. Wouldn’t it have been a lot simpler if he’d just given all the complexifying cells the ability to add to their number when they needed to?
DAVID: Remember He specifically did in the hippocampus. If that ability is not elsewhere, that was His choice and answers your question.
dhw: It shows that the cells are capable of adding to their number! And so there is no reason to suppose that the same ability was NOT present in other parts of our ancestors’ brains, but when it came to us, complexification took over. We don’t know why the human brain stopped expanding. You reject the idea that it might have caused anatomical problems, but you have not provided any other explanation.
I have explained it!!! It is complex enough to handle all our needs into the future.
dhw: You simply agree that the autonomous mechanism for complexification took over. Once more: if you believe your God gave past and present cells the autonomous ability to complexify, why do you regard it as impossible for him to have given all of them the autonomous ability to add to their number (as shown by the modern hippocampus)?
With God in control, He did all He wished. What we see is obviously reflecting His exact wishes.
DAVID: And you have offered no answer for the pelvic problem as before.dhw: I have given you the same answer I gave you before, but if you prefer your own theory that your God preprogrammed bigger heads and pelvises 3.8 billion years ago, or performed operations on all those women’s pelvises, that’s fine. Death in childbirth wasn’t all that uncommon in historic times, so it’s perfectly conceivable that such a problem would have caused more deaths in pre-historic times.
DAVID: You are very uncaring for our ancestors.
dhw: This has nothing to do with me “caring”! With your doctor’s knowledge of all the problems relating to childbirth, why are you so certain that our ancestors had no problems and God “arranged it so new heads fit into new sized brains all at once”? Has he been so uncaring for all those sapiens mums who never made it?
It turns out our birth canal is still tough to navigate.
Human evolution; savannah theory fading
Brain expansion
dhw: […] Are you now saying that your God had to specially design all the cells that were added to earlier cortices and give them a special new ability for complexification?
DAVID: Of course.
dhw: But I thought you agreed that earlier brain cells already had the autonomous ability to complexify. So when God operated on all these sleeping homos, he added the new cortex cells to the old ones, and separately designed the same ability to complexify as that of the existing cortex cells. Wouldn’t it have been a lot simpler if he’d just given all the complexifying cells the ability to add to their number when they needed to?
DAVID: Remember He specifically did in the hippocampus. If that ability is not elsewhere, that was His choice and answers your question.
dhw: It shows that the cells are capable of adding to their number! And so there is no reason to suppose that the same ability was NOT present in other parts of our ancestors’ brains, but when it came to us, complexification took over. We don’t know why the human brain stopped expanding. You reject the idea that it might have caused anatomical problems, but you have not provided any other explanation.
DAVID: I have explained it!!! It is complex enough to handle all our needs into the future.
Thank you. I had forgotten. But I wonder why the ability to complexify was suddenly enhanced to the degree that expansion was no longer necessary. Did your God decide he’d had enough of performing all these operations on sleeping hominins and homos, and he’d leave all future “operations” to the cells themselves – apart perhaps from one final fling with the hippocampus?
dhw: You simply agree that the autonomous mechanism for complexification took over. Once more: if you believe your God gave past and present cells the autonomous ability to complexify, why do you regard it as impossible for him to have given all of them the autonomous ability to add to their number (as shown by the modern hippocampus)?
DAVID: With God in control, He did all He wished. What we see is obviously reflecting His exact wishes.
And how do you know his exact wishes, and how does this prove that he did NOT give cells the ability to multiply?
DAVID: And you have offered no answer for the pelvic problem as before.
dhw: I have given you the same answer I gave you before, but if you prefer your own theory that your God preprogrammed bigger heads and pelvises 3.8 billion years ago, or performed operations on all those women’s pelvises, that’s fine. Death in childbirth wasn’t all that uncommon in historic times, so it’s perfectly conceivable that such a problem would have caused more deaths in pre-historic times.
DAVID: You are very uncaring for our ancestors.
dhw: This has nothing to do with me “caring”! With your doctor’s knowledge of all the problems relating to childbirth, why are you so certain that our ancestors had no problems and God “arranged it so new heads fit into new sized brains all at once”? Has he been so uncaring for all those sapiens mums who never made it?
DAVID: It turns out our birth canal is still tough to navigate.
Yes indeed, so why do you think our pre-historic ancestors had no trouble back in the days when baby skulls got bigger?
Human evolution; savannah theory fading
by David Turell , Monday, August 15, 2022, 18:08 (829 days ago) @ dhw
Brain expansion
dhw: […] Are you now saying that your God had to specially design all the cells that were added to earlier cortices and give them a special new ability for complexification?
DAVID: Of course.
DAVID: Remember He specifically did in the hippocampus. If that ability is not elsewhere, that was His choice and answers your question.
dhw: It shows that the cells are capable of adding to their number! And so there is no reason to suppose that the same ability was NOT present in other parts of our ancestors’ brains, but when it came to us, complexification took over. We don’t know why the human brain stopped expanding. You reject the idea that it might have caused anatomical problems, but you have not provided any other explanation.
DAVID: I have explained it!!! It is complex enough to handle all our needs into the future.
dhw: Thank you. I had forgotten. But I wonder why the ability to complexify was suddenly enhanced to the degree that expansion was no longer necessary. Did your God decide he’d had enough of performing all these operations on sleeping hominins and homos, and he’d leave all future “operations” to the cells themselves – apart perhaps from one final fling with the hippocampus?
A designer knows when His design is complete.
dhw: You simply agree that the autonomous mechanism for complexification took over. Once more: if you believe your God gave past and present cells the autonomous ability to complexify, why do you regard it as impossible for him to have given all of them the autonomous ability to add to their number (as shown by the modern hippocampus)?DAVID: With God in control, He did all He wished. What we see is obviously reflecting His exact wishes.
dhw: And how do you know his exact wishes, and how does this prove that he did NOT give cells the ability to multiple?
Cells do multiply. Why did you ask? And I have said we cannot know God's personal reasons.
DAVID: And you have offered no answer for the pelvic problem as before.dhw: I have given you the same answer I gave you before, but if you prefer your own theory that your God preprogrammed bigger heads and pelvises 3.8 billion years ago, or performed operations on all those women’s pelvises, that’s fine. Death in childbirth wasn’t all that uncommon in historic times, so it’s perfectly conceivable that such a problem would have caused more deaths in pre-historic times.
DAVID: You are very uncaring for our ancestors.
dhw: This has nothing to do with me “caring”! With your doctor’s knowledge of all the problems relating to childbirth, why are you so certain that our ancestors had no problems and God “arranged it so new heads fit into new sized brains all at once”? Has he been so uncaring for all those sapiens mums who never made it?
DAVID: It turns out our birth canal is still tough to navigate.
dhw: Yes indeed, so why do you think our pre-historic ancestors had no trouble back in the days when baby skulls got bigger?
I'm sure they faced the same obstetric problems we do.
Human evolution; savannah theory fading
by David Turell , Monday, August 15, 2022, 22:02 (829 days ago) @ David Turell
Brain expansion
DAVID: I have explained it!!! It is complex enough to handle all our needs into the future.
dhw: Thank you. I had forgotten. But I wonder why the ability to complexify was suddenly enhanced to the degree that expansion was no longer necessary. Did your God decide he’d had enough of performing all these operations on sleeping hominins and homos, and he’d leave all future “operations” to the cells themselves – apart perhaps from one final fling with the hippocampus?
A designer knows when His design is complete.
This new study shows this:
https://www.newscientist.com/article/2333604-people-with-half-a-brain-removed-do-well-a...
"Adults who had one half of their brain removed in childhood to treat seizures can still recognise faces and words at a reasonably high level, suggesting that the organ can reorganise itself after major childhood surgery.
"It is typically understood that word recognition is generally processed in the left hemisphere of the brain and face recognition occurs in the right hemisphere.
***
"The team tested 40 individuals who underwent surgery in childhood to remove their left or right brain hemisphere in order to stop epileptic seizures.
"Of the participants, 16 still had their left cerebral hemisphere and 24 had their right hemisphere. Known as a hemispherectomy, the surgery is rare and used as a last resort to treat severe seizures that originate from one side of the brain. Research suggests the surgery is effective at stopping seizures and causes no significant loss of language function or IQ.
***
"The team thought people with only their right hemisphere would perform better at face recognition, while those with just their left hemisphere were expected to score more highly at word recognition.
Instead, the people who had their left or right hemisphere removed scored an average accuracy of 86 per cent across both tasks, compared with 96 per cent accuracy in the control group.
***
"The latest study suggests that the childhood brain is very plastic, says Daniel Mirman at the University of Edinburgh in the UK. “If only one hemisphere’s resources are available, then both behaviours will rely on that resource rather than splitting it between the two hemispheres,” he says.
“The fact that above-chance and broadly comparable performance for face and word recognition can be achieved following childhood hemispherectomy attests to the remarkable adaptability of the juvenile brain,” says David Wilkinson at the University of Kent in the UK."
Comment: Makes the point!!!
Human evolution; savannah theory fading
Brain expansion
dhw: […] we don’t know why the human brain stopped expanding. You reject the idea that it might have caused anatomical problems, but you have not provided any other explanation.
DAVID: I have explained it!!! It is complex enough to handle all our needs into the future.
dhw: Thank you. I had forgotten. But I wonder why the ability to complexify was suddenly enhanced to the degree that expansion was no longer necessary. Did your God decide he’d had enough of performing all these operations on sleeping hominins and homos, and he’d leave all future “operations” to the cells themselves – apart perhaps from one final fling with the hippocampus?
DAVID: A designer knows when His design is complete.
Which brings us back to the question why your all-powerful God designed umpteen varieties of hominins, homos and brains before finally producing the only one he actually wanted to design. But of course, only God knows why, and he couldn’t possibly have been experimenting, or getting new ideas as he went along, because such a theory entails human thought patterns, and he only has those human thought patterns of which you approve.
dhw: Once more: if you believe your God gave past and present cells the autonomous ability to complexify, why do you regard it as impossible for him to have given all of them the autonomous ability to add to their number (as shown by the modern hippocampus)?
DAVID: With God in control, He did all He wished. What we see is obviously reflecting His exact wishes.
dhw: And how do you know his exact wishes, and how does this prove that he did NOT give cells the ability to multiplY?
DAVID: Cells do multiply. Why did you ask? And I have said we cannot know God's personal reasons.
You keep telling us that early brain cells could not have added to their number, and so God had to engineer their expansion (multiplication). Do you now accept that early brains might have had an autonomous mechanism for expansion as well as for complexification?
DAVID: And you have offered no answer for the pelvic problem as before.
dhw: I have given you the same answer I gave you before, but if you prefer your own theory that your God preprogrammed bigger heads and pelvises 3.8 billion years ago, or performed operations on all those women’s pelvises, that’s fine. Death in childbirth wasn’t all that uncommon in historic times, so it’s perfectly conceivable that such a problem would have caused more deaths in pre-historic times.
DAVID: You are very uncaring for our ancestors.
dhw: This has nothing to do with me “caring”! With your doctor’s knowledge of all the problems relating to childbirth, why are you so certain that our ancestors had no problems and God “arranged it so new heads fit into new sized brains all at once”? Has he been so uncaring for all those sapiens mums who never made it?
DAVID: It turns out our birth canal is still tough to navigate.
dhw: Yes indeed, so why do you think our pre-historic ancestors had no trouble back in the days when baby skulls got bigger?
DAVID: I'm sure they faced the same obstetric problems we do.
Probably a darn sight worse. So what is all this about God arranging it “so new heads fit into new sized brains all at once”?
Hemispherectomy
QUOTES: "Adults who had one half of their brain removed in childhood to treat seizures can still recognise faces and words at a reasonably high level, suggesting that the organ can reorganise itself after major childhood surgery.”
“The fact that above-chance and broadly comparable performance for face and word recognition can be achieved following childhood hemispherectomy attests to the remarkable adaptability of the juvenile brain,” says David Wilkinson at the University of Kent in the UK."
DAVID: Makes the point!!!
It certainly does. You could hardly have a clearer illustration of the way brain cells autonomously change themselves in order to meet new requirements. Or do you think your God pops in to perform additional operations after the surgeons have done their job?
Human evolution; savannah theory fading
by David Turell , Tuesday, August 16, 2022, 18:13 (828 days ago) @ dhw
Brain expansion
DAVID: A designer knows when His design is complete.
dhw: Which brings us back to the question why your all-powerful God designed umpteen varieties of hominins, homos and brains before finally producing the only one he actually wanted to design. But of course, only God knows why, and he couldn’t possibly have been experimenting, or getting new ideas as he went along, because such a theory entails human thought patterns, and he only has those human thought patterns of which you approve.
I have presented to you the evidence that God prefers to evolve all of His creations. Must
I repeat? He evolved the universe, Earth, life.
dhw: And how do you know his exact wishes, and how does this prove that he did NOT give cells the ability to multiplY?
DAVID: Cells do multiply. Why did you ask? And I have said we cannot know God's personal reasons.
dhw: You keep telling us that early brain cells could not have added to their number, and so God had to engineer their expansion (multiplication). Do you now accept that early brains might have had an autonomous mechanism for expansion as well as for complexification?
Our brain's abilities reflect the past brains. I assume thet\y worked as ours does, new neurons in hippocampus only,.
DAVID: And you have offered no answer for the pelvic problem as before.DAVID: It turns out our birth canal is still tough to navigate.
dhw: Yes indeed, so why do you think our pre-historic ancestors had no trouble back in the days when baby skulls got bigger?
DAVID: I'm sure they faced the same obstetric problems we do.
dhw: Probably a darn sight worse. So what is all this about God arranging it “so new heads fit into new sized brains all at once”?
Old homo birth canals were just like ours under God's deigns.
HemispherectomyQUOTES: "Adults who had one half of their brain removed in childhood to treat seizures can still recognise faces and words at a reasonably high level, suggesting that the organ can reorganise itself after major childhood surgery.”
“The fact that above-chance and broadly comparable performance for face and word recognition can be achieved following childhood hemispherectomy attests to the remarkable adaptability of the juvenile brain,” says David Wilkinson at the University of Kent in the UK."DAVID: Makes the point!!!
dhw: It certainly does. You could hardly have a clearer illustration of the way brain cells autonomously change themselves in order to meet new requirements. Or do you think your God pops in to perform additional operations after the surgeons have done their job?
No, He gave the brain the abilities we see. No stepping in.
Human evolution; savannah theory fading
Brain expansion
DAVID: A designer knows when His design is complete.
dhw: Which brings us back to the question why your all-powerful God designed umpteen varieties of hominins, homos and brains before finally producing the only one he actually wanted to design. But of course, only God knows why, and he couldn’t possibly have been experimenting, or getting new ideas as he went along, because such a theory entails human thought patterns, and he only has those human thought patterns of which you approve.
DAVID: I have presented to you the evidence that God prefers to evolve all of His creations. Must I repeat? He evolved the universe, Earth, life.
You don’t need to repeat your belief in evolution, which I share. The problem you yourself have found insoluble is why he chose to design sapiens in stages, although he was capable of designing species without precursors. You have acknowledged that you have no idea why. I have offered you two logical theories to explain why, but you reject them on the grounds which I have bolded above.
dhw: [...] how do you know his exact wishes, and how does this prove that he did NOT give cells the ability to multiplY?
DAVID: Cells do multiply. Why did you ask? And I have said we cannot know God's personal reasons.
dhw: You keep telling us that early brain cells could not have added to their number, and so God had to engineer their expansion (multiplication). Do you now accept that early brains might have had an autonomous mechanism for expansion as well as for complexification?
DAVID: Our brain's abilities reflect the past brains. I assume they worked as ours does, new neurons in hippocampus only.
I agree totally that our abilities reflect those of the past, i.e. that the cells could autonomously complexify (you agree) and multiply (as shown by the modern hippocampus), and we have agreed that otherwise, complexification took over from multiplication in the sapiens brain. You have no reason to assume that your God did not give both abilities to the brains of our predecessors.
Prehistoric brains and pelvises
DAVID: It turns out our birth canal is still tough to navigate.
dhw: Yes indeed, so why do you think our pre-historic ancestors had no trouble back in the days when baby skulls got bigger?
DAVID: I'm sure they faced the same obstetric problems we do.
dhw: Probably a darn sight worse. So what is all this about God arranging it “so new heads fit into new sized brains all at once”? [dhw: see below for the complete quote.]
DAVID: Old homo birth canals were just like ours under God's deigns.
My answer to what you called the “pelvic problem” was that the cell communities would have adjusted themselves to accommodate the new sized skull, but no doubt there would initially have been a lot of deaths during childbirth. You pooh-poohed this possibility because God would have arranged it “so new heads fit into new sized brains all at once without all those messy deaths you prescribe”? Do you now accept the possibility that there would have been a lot of deaths during childbirth as a result of the new sized skull?
Hemispherectomy
QUOTES: "Adults who had one half of their brain removed in childhood to treat seizures can still recognise faces and words at a reasonably high level, suggesting that the organ can reorganise itself after major childhood surgery.”
“The fact that above-chance and broadly comparable performance for face and word recognition can be achieved following childhood hemispherectomy attests to the remarkable adaptability of the juvenile brain,” says David Wilkinson at the University of Kent in the UK."
DAVID: Makes the point!!!
dhw: It certainly does. You could hardly have a clearer illustration of the way brain cells autonomously change themselves in order to meet new requirements. Or do you think your God pops in to perform additional operations after the surgeons have done their job?
DAVID: No, He gave the brain the abilities we see. No stepping in.
Thank you for confirming my proposal that if God exists, he would have given cells the autonomous ability to change themselves in order to meet new requirements.
Human evolution; savannah theory fading
by David Turell , Wednesday, August 17, 2022, 19:01 (827 days ago) @ dhw
Brain expansion
dhw: [...] how do you know his exact wishes, and how does this prove that he did NOT give cells the ability to multiplY?
DAVID: Cells do multiply. Why did you ask? And I have said we cannot know God's personal reasons.
dhw: You keep telling us that early brain cells could not have added to their number, and so God had to engineer their expansion (multiplication). Do you now accept that early brains might have had an autonomous mechanism for expansion as well as for complexification?
DAVID: Our brain's abilities reflect the past brains. I assume they worked as ours does, new neurons in hippocampus only.
dhw: I agree totally that our abilities reflect those of the past, i.e. that the cells could autonomously complexify (you agree) and multiply (as shown by the modern hippocampus), and we have agreed that otherwise, complexification took over from multiplication in the sapiens brain. You have no reason to assume that your God did not give both abilities to the brains of our predecessors.
You can assume that possibility as pure unsubstantiated theory.
Prehistoric brains and pelvisesDAVID: It turns out our birth canal is still tough to navigate.
dhw: Yes indeed, so why do you think our pre-historic ancestors had no trouble back in the days when baby skulls got bigger?
DAVID: I'm sure they faced the same obstetric problems we do.
dhw: Probably a darn sight worse. So what is all this about God arranging it “so new heads fit into new sized brains all at once”? [dhw: see below for the complete quote.]
DAVID: Old homo birth canals were just like ours under God's designs.
dhw: My answer to what you called the “pelvic problem” was that the cell communities would have adjusted themselves to accommodate the new sized skull, but no doubt there would initially have been a lot of deaths during childbirth. You pooh-poohed this possibility because God would have arranged it “so new heads fit into new sized brains all at once without all those messy deaths you prescribe”? Do you now accept the possibility that there would have been a lot of deaths during childbirth as a result of the new sized skull?
My kind God provides for all required changes as He designs for future use.
HemispherectomyQUOTES: "Adults who had one half of their brain removed in childhood to treat seizures can still recognise faces and words at a reasonably high level, suggesting that the organ can reorganise itself after major childhood surgery.”
“The fact that above-chance and broadly comparable performance for face and word recognition can be achieved following childhood hemispherectomy attests to the remarkable adaptability of the juvenile brain,” says David Wilkinson at the University of Kent in the UK."DAVID: Makes the point!!!
dhw: It certainly does. You could hardly have a clearer illustration of the way brain cells autonomously change themselves in order to meet new requirements. Or do you think your God pops in to perform additional operations after the surgeons have done their job?
DAVID: No, He gave the brain the abilities we see. No stepping in.
dhw: Thank you for confirming my proposal that if God exists, he would have given cells the autonomous ability to change themselves in order to meet new requirements.
All He gave the neurons is the ability to arrange new networks of connections in complexification.
Human evolution; savannah theory fading
Brain expansion
DAVID: Our brain's abilities reflect the past brains. I assume they worked as ours does, new neurons in hippocampus only.
dhw: I agree totally that our abilities reflect those of the past, i.e. that the cells could autonomously complexify (you agree) and multiply (as shown by the modern hippocampus), and we have agreed that otherwise, complexification took over from multiplication in the sapiens brain. You have no reason to assume that your God did not give both abilities to the brains of our predecessors.
DAVID: You can assume that possibility as pure unsubstantiated theory.
Nobody knows the truth, which is why we have different theories. However, since the hippocampus apparently has the autonomous ability to enlarge itself, we have evidence of brain cells being able to add autonomously to their numbers, and so the possibility that they were able to do so generally in the past is not entirely unsubstantiated. We also know that for unknown reasons expansion was made unnecessary by means of enhanced complexification, and so - sticking to theism – one might say that your God’s creation of such an autonomous expansion mechanism is at least as feasible as the theory that he kept on performing operations on sleeping hominins and homos in order to give them their new cells.
Prehistoric brains and pelvises
dhw: Death in childbirth wasn’t all that uncommon in historic times, so it’s perfectly conceivable that such a problem would have caused more deaths in prehistoric times.
DAVID: You are very uncaring for our ancestors.[…]
dhw: […] why do you think our prehistoric ancestors had no trouble back in the days when baby skulls got bigger?
DAVID: I'm sure they faced the same obstetric problems we do.
dhw: My answer to what you called the “pelvic problem” was that the cell communities would have adjusted themselves to accommodate the new sized skull, but no doubt there would initially have been a lot of deaths during childbirth. You pooh-poohed this possibility because God would have arranged it “so new heads fit into new sized brains all at once without all those messy deaths you prescribe”? Do you now accept the possibility that there would have been a lot of deaths during childbirth as a result of the new sized skull?
DAVID: My kind God provides for all required changes as He designs for future use.
But do you now accept the possibility that there would have been a lot of deaths in childbirth, as I proposed above?
Hemispherectomy
QUOTES: "Adults who had one half of their brain removed in childhood to treat seizures can still recognise faces and words at a reasonably high level, suggesting that the organ can reorganise itself after major childhood surgery.”
“The fact that above-chance and broadly comparable performance for face and word recognition can be achieved following childhood hemispherectomy attests to the remarkable adaptability of the juvenile brain,” says David Wilkinson at the University of Kent in the UK."
DAVID: Makes the point!!!
dhw: It certainly does. You could hardly have a clearer illustration of the way brain cells autonomously change themselves in order to meet new requirements. Or do you think your God pops in to perform additional operations after the surgeons have done their job?
DAVID: No, He gave the brain the abilities we see. No stepping in.
dhw: Thank you for confirming my proposal that if God exists, he would have given cells the autonomous ability to change themselves in order to meet new requirements.
DAVID: All He gave the neurons is the ability to arrange new networks of connections in complexification.
That is all they need now, since expansion has ceased and complexification has taken over. But I’m happy with your conclusion, as you agree that brain cells are capable of changing themselves autonomously in order to meet new requirements. If brain cells can do this in the present, and we know for a fact that other cells can also make the minor changes necessary for adaptation, there is no reason to assume that other cell communities did not have the same autonomous capabilities in the past, when full speciation took place (as opposed to varieties, which we also call species). The current period of evolutionary stasis is very short compared to those of the past, and who knows what new species might be formed by the same autonomous mechanisms if (when?) our planet – or parts of it - undergoes radical changes? It is pleasing to see you gradually coming round to the fact that your God could and did give a degree of autonomous, creative intelligence to cell communities.
Human evolution; savannah theory fading
by David Turell , Thursday, August 18, 2022, 17:36 (826 days ago) @ dhw
Brain expansion
DAVID: You can assume that possibility as pure unsubstantiated theory.
dhw: Nobody knows the truth, which is why we have different theories. However, since the hippocampus apparently has the autonomous ability to enlarge itself, we have evidence of brain cells being able to add autonomously to their numbers, and so the possibility that they were able to do so generally in the past is not entirely unsubstantiated. We also know that for unknown reasons expansion was made unnecessary by means of enhanced complexification, and so - sticking to theism – one might say that your God’s creation of such an autonomous expansion mechanism is at least as feasible as the theory that he kept on performing operations on sleeping hominins and homos in order to give them their new cells.
Why is one of God's actions feasible (complexification) and brain enlargement not? Sticking to confused attempts at theism!!!
Prehistoric brains and pelvisesdhw: My answer to what you called the “pelvic problem” was that the cell communities would have adjusted themselves to accommodate the new sized skull, but no doubt there would initially have been a lot of deaths during childbirth. You pooh-poohed this possibility because God would have arranged it “so new heads fit into new sized brains all at once without all those messy deaths you prescribe”? Do you now accept the possibility that there would have been a lot of deaths during childbirth as a result of the new sized skull?
DAVID: My kind God provides for all required changes as He designs for future use.
dhw: But do you now accept the possibility that there would have been a lot of deaths in childbirth, as I proposed above?
No. But more than ours now, yes.
HemispherectomyDAVID: No, He gave the brain the abilities we see. No stepping in.
dhw: Thank you for confirming my proposal that if God exists, he would have given cells the autonomous ability to change themselves in order to meet new requirements.
DAVID: All He gave the neurons is the ability to arrange new networks of connections in complexification.
dhw: That is all they need now, since expansion has ceased and complexification has taken over. But I’m happy with your conclusion, as you agree that brain cells are capable of changing themselves autonomously in order to meet new requirements. If brain cells can do this in the present, and we know for a fact that other cells can also make the minor changes necessary for adaptation, there is no reason to assume that other cell communities did not have the same autonomous capabilities in the past, when full speciation took place (as opposed to varieties, which we also call species). The current period of evolutionary stasis is very short compared to those of the past, and who knows what new species might be formed by the same autonomous mechanisms if (when?) our planet – or parts of it - undergoes radical changes? It is pleasing to see you gradually coming round to the fact that your God could and did give a degree of autonomous, creative intelligence to cell communities.
Not evolutionary stasis. We are its endpoint under God's designs. The only gift God gave neurons was the ability to complexify networks to handle new mental needs. All brain thickening was the volume of increased wiring.
Human evolution; savannah theory fading
Brain expansion
DAVID: You can assume that possibility as pure unsubstantiated theory.
dhw: Nobody knows the truth, which is why we have different theories. However, since the hippocampus apparently has the autonomous ability to enlarge itself, we have evidence of brain cells being able to add autonomously to their numbers, and so the possibility that they were able to do so generally in the past is not entirely unsubstantiated. We also know that for unknown reasons expansion was made unnecessary by means of enhanced complexification, and so - sticking to theism – one might say that your God’s creation of such an autonomous expansion mechanism is at least as feasible as the theory that he kept on performing operations on sleeping hominins and homos in order to give them their new cells.
DAVID: Why is one of God's actions feasible (complexification) and brain enlargement not? Sticking to confused attempts at theism!!!
That is the question I keep asking you! My theistic proposal is that he gave cells the autonomous abilities to complexify and to multiply. You agree to the first, and reject the second! Why?
Prehistoric brains and pelvises
dhw: My answer to what you called the “pelvic problem” was that the cell communities would have adjusted themselves to accommodate the new sized skull, but no doubt there would initially have been a lot of deaths during childbirth. You pooh-poohed this possibility because God would have arranged it “so new heads fit into new sized brains all at once without all those messy deaths you prescribe”? Do you now accept the possibility that there would have been a lot of deaths during childbirth as a result of the new sized skull?
DAVID: My kind God provides for all required changes as He designs for future use.
dhw: But do you now accept the possibility that there would have been a lot of deaths in childbirth, as I proposed above?
DAVID: No. But more than ours now, yes.
So we return to my solution to the “pelvic problem”. It would have taken time for the relevant cell communities to adjust to the new sized baby skull, and no doubt this would have caused a lot of deaths in childbirth. Your objection is no longer that your God stepped in to ensure that there were no messy deaths, but God stepped in to ensure that there were fewer deaths than “a lot” of deaths.
Hemispherectomy
DAVID: He gave the brain the abilities we see. No stepping in.
dhw: Thank you for confirming my proposal that if God exists, he would have given cells the autonomous ability to change themselves in order to meet new requirements.
DAVID: All He gave the neurons is the ability to arrange new networks of connections in complexification.
dhw: That is all they need now, since expansion has ceased and complexification has taken over. But I’m happy with your conclusion, as you agree that brain cells are capable of changing themselves autonomously in order to meet new requirements. If brain cells can do this in the present, and we know for a fact that other cells can also make the minor changes necessary for adaptation, there is no reason to assume that other cell communities did not have the same autonomous capabilities in the past, when full speciation took place (as opposed to varieties, which we also call species). The current period of evolutionary stasis is very short compared to those of the past, and who knows what new species might be formed by the same autonomous mechanisms if (when?) our planet – or parts of it - undergoes radical changes? It is pleasing to see you gradually coming round to the fact that your God could and did give a degree of autonomous, creative intelligence to cell communities.
DAVID: Not evolutionary stasis. We are its endpoint under God's designs.
I’m pleased to see that you have no objections to my argument that past cells might have had the same autonomous abilities as present cells to make the changes needed to meet new requirements. Whether evolution has now finished is a question none of us can answer – unless you happen to have a reliable crystal ball to observe Planet Earth as it will be in, say, a billion years’ time.
Human evolution; savannah theory fading
by David Turell , Friday, August 19, 2022, 18:54 (825 days ago) @ dhw
edited by David Turell, Friday, August 19, 2022, 19:29
Brain expansion
DAVID: Why is one of God's actions feasible (complexification) and brain enlargement not? Sticking to confused attempts at theism!!!
dhw: That is the question I keep asking you! My theistic proposal is that he gave cells the autonomous abilities to complexify and to multiply. You agree to the first, and reject the second! Why?
Same old answer: cell committees are not capable of design for future uses and needs.
Prehistoric brains and pelvisesDAVID: My kind God provides for all required changes as He designs for future use.
dhw: But do you now accept the possibility that there would have been a lot of deaths in childbirth, as I proposed above?
DAVID: No. But more than ours now, yes.
dhw: So we return to my solution to the “pelvic problem”. It would have taken time for the relevant cell communities to adjust to the new sized baby skull, and no doubt this would have caused a lot of deaths in childbirth. Your objection is no longer that your God stepped in to ensure that there were no messy deaths, but God stepped in to ensure that there were fewer deaths than “a lot” of deaths.
I'm looking at pre-historic birthing in light of the present difficulties. Obstetricians currently can solve more complications than cave folks back then. God did what he could to accommodate walking and big head birthing all at once.
Genetic formation of our pelvis:
https://www.sciencemagazinedigital.org/sciencemagazine/library/item/19_august_2022/4035...
"The wide, basin-shaped human pelvis is a defining physical feature of our species. Without it, we couldn’t walk upright or give birth to big-brained babies. Now, a new study of human embryos has pinpointed the window in embryonic development during which the pelvis begins to look humanlike and identified hundreds of genes and regulatory RNA regions that drive this transformation. Many bear the hallmarks of strong natural selection for bipedalism, the authors conclude.
***
"By comparing the developing pelvis’ genetic activity with a mouse model’s, the researchers also identified thousands of genetic on/off switches seemingly involved in shaping the human pelvis. Stretches of DNA within those switches appear to have evolved rapidly since our species’ split from our common ancestor with chimpanzees. But among modern humans, those regulatory bits in the ilium show strikingly little variation. That uniformity, the researchers say, is a sign that natural selection put—and continues to put—intense pressure on the ilium to develop in a highly specific way."
Comment: all that genetic activity by cell committees? Impossible!!!
HemispherectomyDAVID: He gave the brain the abilities we see. No stepping in.
dhw: Thank you for confirming my proposal that if God exists, he would have given cells the autonomous ability to change themselves in order to meet new requirements.
DAVID: All He gave the neurons is the ability to arrange new networks of connections in complexification.
dhw: That is all they need now, since expansion has ceased and complexification has taken over. But I’m happy with your conclusion, as you agree that brain cells are capable of changing themselves autonomously in order to meet new requirements. If brain cells can do this in the present, and we know for a fact that other cells can also make the minor changes necessary for adaptation, there is no reason to assume that other cell communities did not have the same autonomous capabilities in the past, when full speciation took place (as opposed to varieties, which we also call species). The current period of evolutionary stasis is very short compared to those of the past, and who knows what new species might be formed by the same autonomous mechanisms if (when?) our planet – or parts of it - undergoes radical changes? It is pleasing to see you gradually coming round to the fact that your God could and did give a degree of autonomous, creative intelligence to cell communities.
DAVID: Not evolutionary stasis. We are its endpoint under God's designs.
dhw: I’m pleased to see that you have no objections to my argument that past cells might have had the same autonomous abilities as present cells to make the changes needed to meet new requirements. Whether evolution has now finished is a question none of us can answer – unless you happen to have a reliable crystal ball to observe Planet Earth as it will be in, say, a billion years’ time.
I still reject your cell driven enlargement of the brain. I ignored responding to it above.
Human evolution; our great migrationa
by David Turell , Friday, August 19, 2022, 19:52 (825 days ago) @ David Turell
Covered in a new book:
https://www.sciencenews.org/article/human-evolution-five-million-year-odyssey-review
So it’s fitting that his new book, a plain-English summary of what’s known and what’s not about the evolution of humans and our ancestors, emphasizes movement. In The Five-Million-Year Odyssey, Bellwood examines a parade of species in the human evolutionary family — he collectively refers to them as hominins, whereas some others (including Science News) use the term hominids (SN: 9/15/21) — and tracks their migrations across land and sea. He marshals evidence indicating that hominids in motion continually shifted the direction of biological and cultural evolution.
***
Species from at least 4.4 million years ago or more whose hominid status is controversial, such as Ardipithecus ramidus, get a brief mention. Bellwood renders no verdict on whether those finds come from early hominids or ancient apes. He focuses instead on African australopithecines, a set of upright but partly apelike species thought to have included populations that evolved into members of our own genus, Homo, around 2.5 million to 3 million years ago. Bellwood hammers home the point that stone-tool making by the last australopithecines, the first Homo groups or both contributed to the evolution of bigger brains in our ancestors.
The action speeds up when Homo erectus becomes the first known hominid to leave Africa, roughly 2 million years ago. Questions remain, Bellwood writes, about how many such migrations occurred and whether this humanlike species reached distant islands such as Flores in Indonesia, perhaps giving rise to small hominids called hobbits, or Homo floresiensis (SN: 3/30/16). What’s clear is that H. erectus groups journeyed across mainland Asia and at least as far as the Indonesian island of Java.
***
Bellwood gives considerable attention to the rise of food production and domestication in Europe and Asia after around 9,000 years ago. He builds on an argument, derived from his 2004 book First Farmers, that expanding populations of early cultivators migrated to new lands in such great numbers that they spread major language families with them. For instance, farmers in what’s now Turkey spread Indo-European languages into much of Europe sometime after roughly 8,000 years ago, Bellwood contends.
***
Bellwood rounds out his evolutionary odyssey with a reconstruction of how early agricultural populations expanded through East Asia and beyond, to Australia, a string of Pacific islands and the Americas. Between about 4,000 and 750 years ago, for instance, sea-faring farmers spread Austronesian languages from southern China and Taiwan to Madagascar in the west and Polynesia in the east. Precisely how they accomplished that remarkable feat remains a puzzle.
Comment: I'm sure dhw will notice the effect of necessary food sources driving the migration. And then poo-poo the importance of humans and their food.
To buy:
https://bookshop.org/books/the-five-million-year-odyssey-the-human-journey-from-ape-to-...
Human evolution; explaining hobbits, luzonensis, etc.
by David Turell , Saturday, April 13, 2024, 21:34 (222 days ago) @ David Turell
Who travelled where and evolved who is a mystery; an attempt to unravel:
https://www.newscientist.com/article/2426655-untangling-the-enigmatic-origins-of-the-hu...
"On 10 April 2019, our extended family got a bit bigger. A study in Nature reported the discovery of a new species of hominin called Homo luzonensis, from the Philippines. My colleague and fellow fossil enthusiast Colin Barras wrote about it for New Scientist.
***
"That story almost surely involves a sea crossing. During the glacial periods, sea levels were lower because so much water was locked up in the ice caps. As a result, many places that are now islands, like Borneo and Sumatra, were connected to mainland Asia – forming a vast expanse of land called Sunda. However, it seems Luzon was always an island.
"The implication is that some population of hominins, wandering vaguely eastwards, made their way to Luzon – accidentally or on purpose. Isolated on the island, they evolved bodies different to those of other hominins, ultimately becoming the distinct species we call H. luzonensis.
***
"First, Luzon has a tropical climate, so it’s unlikely ancient DNA has been preserved – and indeed, attempts to extract it from the H. luzonensis remains have been unsuccessful. This cuts off a key line of evidence.
***
"Secondly, we only have one set of remains of H. luzonensis. This means we don’t know how long they lived on Luzon. A 2018 study found the earliest known hominin activity in the Philippines on Luzon, in the form of stone tools and butchered rhino bones. These artefacts were 709,000 years old. Conceivably the hominins involved were H. luzonensis or their direct ancestors, but no hominin bones were found so we have no way of knowing. The two findings could be completely unrelated.
"This means a wide variety of hominins are in the frame. One candidate is Homo erectus, which was living outside of Africa at least 1.8 million years ago and survived at Ngandong on Java until as recently as 108,000 years ago. It seems distinctly possible that some H. erectus made it to Luzon.
"Another possibility is the “hobbits”, Homo floresiensis, known from the island of Flores in Indonesia. It’s conceivable that some of them made it to Luzon and then became isolated there. However, there’s no sign of the hobbits outside of Flores. The timings also may not work: the hobbits probably lived on Flores between 190,000 and 50,000 years ago, so if H. luzonensis turns out to be older than that, the hobbits can’t be their ancestors.
"The third possibility is the Denisovans, whose remains have been found on mainland Asia in the Altai Mountains and Tibetan plateau. Today many people in island South-East Asia carry Denisovan DNA, suggesting the Denisovans roamed Sunda as well as what we now think of as the mainland. Intriguingly, a 2021 study found that groups called Ayta living on Luzon have the highest level of Denisovan ancestry in the world, hinting that the Denisovans visited the island. However, we have few confirmed Denisovan remains, so we don’t know how long they were around.
"Finally, there is the most dramatic possibility: that H. luzonensis is directly descended from an Australopithecus. These earlier hominins have only been found in Africa, but it’s conceivable that some of them did wander outside the continent. In the original 2019 study, the researchers described a number of attributes of the H. luzonensis remains that are not found in other Homo species but are found in Australopithecus.
"Two studies point to a link with H. erectus. In 2022, Détroit, Mijares and their colleagues published a study of H. luzonensis teeth. They compared the teeth with those of several other hominins. The crowns of the teeth were most like those of H. erectus in their external shape, while the internal structures were most similar to those of H. erectus and of hobbits. The team interpreted this to mean that both H. luzonensis and H. floresiensis were descended from H. erectus.
"In line with this, a 2023 study by an independent group argued that H. luzonensis and H. floresiensis are both similar enough to known H. erectus fossils, and separated enough in time, that we should not be unduly surprised by their existence. Put another way, there was plenty of time for H. erectus populations to evolve into these different forms.
***
"The Australopithecus idea is clearly the most radical and therefore the one that excites me the most. Nevertheless, I’m wary of claiming that H. luzonensis is a direct descendant of an Australopithecus. Yes, the similarities are there, but evolution often throws up the same thing multiple times in different species: it’s called convergent evolution. I would want to see a lot more of the skeleton and a lot more similarities to Australopithecus.
"The other obvious issue is that we have plenty of evidence of H. erectus in South-East Asia, and no physical evidence of Australopithecus outside Africa. For that reason, I think H. erectus remains the most likely ancestor of H. luzonensis (although possibly via a Denisovan intermediate, if we assume Denisovans are descended from H. erectus)."
Comment: H. erectus certainly got around and arriving on these islands had enough time to fit into a "small island syndrome" development. Environment causes adaptations. A 300,000-year history ending up with a 25,000-year history in the Americas, wandering to the East.
Human evolution; savannah theory fading
Brain expansion
DAVID: Why is one of God's actions feasible (complexification) and brain enlargement not? Sticking to confused attempts at theism!!!
dhw: That is the question I keep asking you! My theistic proposal is that he gave cells the autonomous abilities to complexify and to multiply. You agree to the first, and reject the second! Why?
DAVID: Same old answer: cell committees are not capable of design for future uses and needs.
And later, under “Hemispherectomy”):
DAVID: I still reject your cell driven enlargement of the brain.
Cell communities do not design for future uses and needs that are not yet known. They design responses to current needs, and when the future throws up new needs, they design for them too. Whatever they design will of course be used in the future so long as it is still needed. Your answer is totally irrelevant to my question. Complexification is the process used by cells in their response to current needs, and you have agreed that this takes place autonomously. Multiplication provided the additional cells when the existing capacity for complexification was insufficient to deal with new requirements. So why do you think your God gave cells the autonomous ability to complexify, but could not possibly have given them the ability to add to their number when they needed to?
Prehistoric brains and pelvises
DAVID: My kind God provides for all required changes as He designs for future use.
dhw: But do you now accept the possibility that there would have been a lot of deaths in childbirth, as I proposed above?
DAVID: No. But more than ours now, yes.
dhw: So we return to my solution to the “pelvic problem”. It would have taken time for the relevant cell communities to adjust to the new sized baby skull, and no doubt this would have caused a lot of deaths in childbirth. Your objection is no longer that your God stepped in to ensure that there were no messy deaths, but God stepped in to ensure that there were fewer deaths than “a lot” of deaths.
DAVID: I'm looking at pre-historic birthing in light of the present difficulties. Obstetricians currently can solve more complications than cave folks back then. God did what he could to accommodate walking and big head birthing all at once.
Very kind of him to use his limited powers, though I’m a bit surprised that he also left it to the cave folks to solve the problems for him. This is getting ridiculous. I offered you a theory to solve what you called the “pelvic problem”, and mentioned that no doubt there would have been lots of deaths in childbirth before the right size became the norm. You were certain that your God would have stepped in to prevent all those “messy deaths”. And now you have him stepping in and failing to achieve his objective. Meanwhile, my theory stands unchallenged.
Genetic formation of our pelvis:
https://www.sciencemagazinedigital.org/sciencemagazine/library/item/19_august_2022/4035...
There is no point in my repeating the quotations, as there is nothing to dispute.
DAVID: all that genetic activity by cell committees? Impossible!!!
According to you! Why do you think your God was incapable of designing intelligent cells which would, in the course of 3.X billion years, devise increasingly complex ways of improving their chances of survival? After all, you insist that he designed our brains, and look what our brain cells have come up with in just a few thousand years!
Human evolution; savannah theory fading
by David Turell , Saturday, August 20, 2022, 19:11 (824 days ago) @ dhw
Brain expansion
DAVID: I still reject your cell driven enlargement of the brain.
dhw: Cell communities do not design for future uses and needs that are not yet known. They design responses to current needs, and when the future throws up new needs, they design for them too. Whatever they design will of course be used in the future so long as it is still needed. Your answer is totally irrelevant to my question. Complexification is the process used by cells in their response to current needs, and you have agreed that this takes place autonomously. Multiplication provided the additional cells when the existing capacity for complexification was insufficient to deal with new requirements. So why do you think your God gave cells the autonomous ability to complexify, but could not possibly have given them the ability to add to their number when they needed to?
We've been over this before. On arrival 315,000 years ago, sapiens had a new brain that had full capacities for future use as history shows. Total facts opposite to your cell producing theory above as if produced with no eye to the future. Still dodging to protect a rigid requiremnt for super intelligent designing cells.
Prehistoric brains and pelvisesDAVID: My kind God provides for all required changes as He designs for future use.
dhw: But do you now accept the possibility that there would have been a lot of deaths in childbirth, as I proposed above?
DAVID: No. But more than ours now, yes.
dhw: So we return to my solution to the “pelvic problem”. It would have taken time for the relevant cell communities to adjust to the new sized baby skull, and no doubt this would have caused a lot of deaths in childbirth. Your objection is no longer that your God stepped in to ensure that there were no messy deaths, but God stepped in to ensure that there were fewer deaths than “a lot” of deaths.
DAVID: I'm looking at pre-historic birthing in light of the present difficulties. Obstetricians currently can solve more complications than cave folks back then. God did what he could to accommodate walking and big head birthing all at once.
dhw: Very kind of him to use his limited powers, though I’m a bit surprised that he also left it to the cave folks to solve the problems for him. This is getting ridiculous. I offered you a theory to solve what you called the “pelvic problem”, and mentioned that no doubt there would have been lots of deaths in childbirth before the right size became the norm. You were certain that your God would have stepped in to prevent all those “messy deaths”. And now you have him stepping in and failing to achieve his objective. Meanwhile, my theory stands unchallenged.
Your theory is let them die until they figure it out.
Genetic formation of our pelvis:
https://www.sciencemagazinedigital.org/sciencemagazine/library/item/19_august_2022/4035...There is no point in my repeating the quotations, as there is nothing to dispute.
DAVID: all that genetic activity by cell committees? Impossible!!!
dhw: According to you! Why do you think your God was incapable of designing intelligent cells which would, in the course of 3.X billion years, devise increasingly complex ways of improving their chances of survival? After all, you insist that he designed our brains, and look what our brain cells have come up with in just a few thousand years!
Yes, that brain was designed for all that future use. You have just destroyed your contention things don't appear deigned future use. Each new species appears just that way.
Human evolution; savannah theory fading
Brain expansion
dhw: […] Complexification is the process used by cells in their response to current needs, and you have agreed that this takes place autonomously. Multiplication provided the additional cells when the existing capacity for complexification was insufficient to deal with new requirements. So why do you think your God gave cells the autonomous ability to complexify, but could not possibly have given them the ability to add to their number when they needed to?
DAVID: We've been over this before. On arrival 315,000 years ago, sapiens had a new brain that had full capacities for future use as history shows.
Correct. The final expansion supplied it with enough cells for the autonomous complexification mechanism to deal with all future requirements.
DAVID: Total facts opposite to your cell producing theory above as if produced with no eye to the future. Still dodging to protect a rigid requiremnt for super intelligent designing cells.
What do you mean by “with an eye to the future”? I propose that the new cells would have been created to meet some new requirement, and from then on, complexification took over from expansion as cells continued to design their responses to each new requirement through complexification. That does not mean your God gazed into his crystal ball and produced the new cells to meet specific requirements that would only arise thousands of years later! Once more: You agree that (if he exists) he gave cells the autonomous ability to make all the changes necessary to meet new requirements. So once more: if he was prepared to give cells the autonomous ability to complexify, why do you think he couldn’t possibly have given them the autonomous ability to add to their number?
Prehistoric brains and pelvises
DAVID: I'm looking at pre-historic birthing in light of the present difficulties. Obstetricians currently can solve more complications than cave folks back then. God did what he could to accommodate walking and big head birthing all at once.
dhw: Very kind of him to use his limited powers, though I’m a bit surprised that he also left it to the cave folks to solve the problems for him. This is getting ridiculous. I offered you a theory to solve what you called the “pelvic problem”, and mentioned that no doubt there would have been lots of deaths in childbirth before the right size became the norm. You were certain that your God would have stepped in to prevent all those “messy deaths”. And now you have him stepping in and failing to achieve his objective. Meanwhile, my theory stands unchallenged.
DAVID: Your theory is let them die until they figure it out.
Who “let them die”? I propose that the cells eventually “figured it out”, but a lot of mothers would have died until the new size became the norm. Your theory seems to be that God did his best to figure it out, but although he failed to the extent that some mothers died, there weren’t “a lot”, so my theory must be wrong. As I said, this is getting ridiculous. Shall we drop the subject?
Genetic formation of our pelvis:
https://www.sciencemagazinedigital.org/sciencemagazine/library/item/19_august_2022/4035...
dhw: There is no point in my repeating the quotations, as there is nothing to dispute.
DAVID: all that genetic activity by cell committees? Impossible!!!
dhw: According to you! Why do you think your God was incapable of designing intelligent cells which would, in the course of 3.X billion years, devise increasingly complex ways of improving their chances of survival? After all, you insist that he designed our brains, and look what our brain cells have come up with in just a few thousand years!
DAVID: Yes, that brain was designed for all that future use. You have just destroyed your contention things don't appear deigned future use. Each new species appears just that way.
The question is why pelvises, brains and species underwent their changes in the first place. According to you, your God preprogrammed or dabbled them all BEFORE there was any need for the changes. My proposal is that they all took place as a RESPONSE to what were then current needs. Once they proved successful, of course they were then used in the future! (See above.)
Human evolution; savannah theory fading
by David Turell , Sunday, August 21, 2022, 14:57 (823 days ago) @ dhw
Brain expansion
DAVID: We've been over this before. On arrival 315,000 years ago, sapiens had a new brain that had full capacities for future use as history shows.
dhw: Correct. The final expansion supplied it with enough cells for the autonomous complexification mechanism to deal with all future requirements.
So you finally agree with me. It came fully prepared for future use.
DAVID: Total facts opposite to your cell producing theory above as if produced with no eye to the future. Still dodging to protect a rigid requiremnt for super intelligent designing cells.dhw: What do you mean by “with an eye to the future”? I propose that the new cells would have been created to meet some new requirement, and from then on, complexification took over from expansion as cells continued to design their responses.
Once again, complexification could work in handling new brain uses precisely because it had so many extra new neurons sitting around with little to do at first.
Prehistoric brains and pelvisesDAVID: Your theory is let them die until they figure it out.
dhw: Who “let them die”? I propose that the cells eventually “figured it out”, but a lot of mothers would have died until the new size became the norm. Your theory seems to be that God did his best to figure it out, but although he failed to the extent that some mothers died, there weren’t “a lot”, so my theory must be wrong. As I said, this is getting ridiculous. Shall we drop the subject?
God set it up so new-sized infant heads fit into their mother's new-sized pelvises.
Genetic formation of our pelvis:
https://www.sciencemagazinedigital.org/sciencemagazine/library/item/19_august_2022/4035...dhw: There is no point in my repeating the quotations, as there is nothing to dispute.
DAVID: all that genetic activity by cell committees? Impossible!!!
dhw: According to you! Why do you think your God was incapable of designing intelligent cells which would, in the course of 3.X billion years, devise increasingly complex ways of improving their chances of survival? After all, you insist that he designed our brains, and look what our brain cells have come up with in just a few thousand years!
DAVID: Yes, that brain was designed for all that future use. You have just destroyed your contention things don't appear deigned future use. Each new species appears just that way.
dhw: The question is why pelvises, brains and species underwent their changes in the first place. According to you, your God preprogrammed or dabbled them all BEFORE there was any need for the changes. My proposal is that they all took place as a RESPONSE to what were then current needs. Once they proved successful, of course they were then used in the future! (See above.)
You have solved the issue of speciation. It is simply adaptation.
Human evolution; savannah theory fading
Brain expansion
DAVID: We've been over this before. On arrival 315,000 years ago, sapiens had a new brain that had full capacities for future use as history shows.
dhw: Correct. The final expansion supplied it with enough cells for the autonomous complexification mechanism to deal with all future requirements.
DAVID: So you finally agree with me. It came fully prepared for future use.
Of course we agree, since there has been no further increase in the number of cells. But we do not agree on your belief that your God operated on a group of sleeping hominins to insert the final collection of cells for the purpose of meeting requirements that would not exist for the next few thousand years. Once more: my proposal is that the new cells were added (by an autonomous mechanism, which may have been designed by your God – like that of complexification) to meet new requirements at that time. From then on, the capacity for complexification took over from expansion as cells continued to design their responses to new requirements, as they had always done.
DAVID: Once again, complexification could work in handling new brain uses precisely because it had so many extra new neurons sitting around with little to do at first.
Complexification had always handled new brain uses until the existing capacity was inadequate to deal with a particular new requirement. And that process of complexification and enlargement would have continued through to ourselves. Extra neurons would not have “sat around with little to do”! They would have performed a specific function. If there was shrinkage, it was because complexification made previously necessary cells redundant; if there was no shrinkage, then all the cells, old and new, were necessary when the extra cells were added, and remained necessary. I don’t know why you think cells would be added simply to sit around until needed. And of course they were also used in the future! That, I suggest, is the basic principle behind all of evolution: changes (in this case extra cells) take place to respond to new current requirements, and if they prove to be useful, they survive for future use.
The next article shows just how difficult it is to assign specific functions to specific parts of the brain:
Cerebellum
DAVID: our large cerebellum, compared to other organisms is finally studied. It arrived 315,000 years ago and performs its duties, and we are now trying to find out how much it does for us.
Yes, the brain is a community of cell communities, just like the rest of the body, and they work together. And – to get back to the major disagreement which has dogged this discussion – you still haven’t explained why your God, who you agree designed a mechanism for autonomous complexification, could not possibly have designed a mechanism for autonomous enlargement.
Prehistoric brains and pelvises
DAVID: Your theory is let them die until they figure it out.
dhw: Who “let them die”? I propose that the cells eventually “figured it out”, but a lot of mothers would have died until the new size became the norm. Your theory seems to be that God did his best to figure it out, but although he failed to the extent that some mothers died, there weren’t “a lot”, so my theory must be wrong. As I said, this is getting ridiculous. Shall we drop the subject?
DAVID: God set it up so new-sized infant heads fit into their mother's new-sized pelvises.
Two days ago, you said there would have been more deaths than in our time, because “obstetricians currently can solve more complications than cave folks back then. God did what he could to accommodate walking and big head birthing all at once.” Are you now saying there were no deaths at all? What did your God do, summon all pregnant women to his operating theatre and give them made-to-measure pelvises? Or there were deaths because of your God’s incompetent surgery? Or he forgot to invite all the women who died? I suggest we drop this subject.
Genetic formation of our pelvis:
dhw: The question is why pelvises, brains and species underwent their changes in the first place. According to you, your God preprogrammed or dabbled them all BEFORE there was any need for the changes. My proposal is that they all took place as a RESPONSE to what were then current needs. Once they proved successful, of course they were then used in the future! (See above.)
DAVID: You have solved the issue of speciation. It is simply adaptation.
It depends what kind of speciation you mean. I would say that larger brains and pelvises were indeed adaptations. (It is believed that there was interbreeding between different types of homos, and the ability to reproduce is one criterion for “species”). But it is sometimes difficult to draw a precise borderline between adaptation and innovation (e.g. pre-whale legs turning to flippers). However, I keep pointing out that evolutionary changes may be in the form of coping with new conditions (adaptation) and exploiting them (through innovations), and I would say that generally it is the latter that create clear speciation.
Human evolution; savannah theory fading
by David Turell , Monday, August 22, 2022, 20:20 (822 days ago) @ dhw
Brain expansion
DAVID: So you finally agree with me. It came fully prepared for future use.
dhw: Of course we agree, since there has been no further increase in the number of cells. But we do not agree on your belief that your God operated on a group of sleeping hominins to insert the final collection of cells for the purpose of meeting requirements that would not exist for the next few thousand years. Once more: my proposal is that the new cells were added (by an autonomous mechanism, which may have been designed by your God – like that of complexification) to meet new requirements at that time. From then on, the capacity for complexification took over from expansion as cells continued to design their responses to new requirements, as they had always done.
Our only disagreeemnt is how the new enlargeed number of neurons arrived in sapeins. I'll stich woth a designer God. But we have agreed the extra cells arrived new and unused in preparation for the future use.
DAVID: Once again, complexification could work in handling new brain uses precisely because it had so many extra new neurons sitting around with little to do at first.dhw: Complexification had always handled new brain uses until the existing capacity was inadequate to deal with a particular new requirement. And that process of complexification and enlargement would have continued through to ourselves. Extra neurons would not have “sat around with little to do”! They would have performed a specific function. If there was shrinkage, it was because complexification made previously necessary cells redundant; if there was no shrinkage, then all the cells, old and new, were necessary when the extra cells were added, and remained necessary. I don’t know why you think cells would be added simply to sit around until needed. And of course they were also used in the future! That, I suggest, is the basic principle behind all of evolution: changes (in this case extra cells) take place to respond to new current requirements, and if they prove to be useful, they survive for future use.
Lots of palaver about all those extra neurons 315,000 years ago, not used as they are now. Note in the caves there was little complicated for them to do. Certainly not reading, typing, deep concptualizing as we do in our discussions
CerebellumDAVID: our large cerebellum, compared to other organisms is finally studied. It arrived 315,000 years ago and performs its duties, and we are now trying to find out how much it does for us.
dhw: Yes, the brain is a community of cell communities, just like the rest of the body, and they work together. And – to get back to the major disagreement which has dogged this discussion – you still haven’t explained why your God, who you agree designed a mechanism for autonomous complexification, could not possibly have designed a mechanism for autonomous enlargement.
Same answer. You want secondhand design. Hands on design is more efficient, without question.
Prehistoric brains and pelvisesDAVID: Your theory is let them die until they figure it out.
dhw: Who “let them die”? I propose that the cells eventually “figured it out”, but a lot of mothers would have died until the new size became the norm. Your theory seems to be that God did his best to figure it out, but although he failed to the extent that some mothers died, there weren’t “a lot”, so my theory must be wrong. As I said, this is getting ridiculous. Shall we drop the subject?
DAVID: God set it up so new-sized infant heads fit into their mother's new-sized pelvises.
dhw: Two days ago, you said there would have been more deaths than in our time, because “obstetricians currently can solve more complications than cave folks back then. God did what he could to accommodate walking and big head birthing all at once.” Are you now saying there were no deaths at all? I suggest we drop this subject.
Total misinterpretation of my statement. All it says is we can solve things now than they couldn't then.
Genetic formation of our pelvis:dhw: The question is why pelvises, brains and species underwent their changes in the first place. According to you, your God preprogrammed or dabbled them all BEFORE there was any need for the changes. My proposal is that they all took place as a RESPONSE to what were then current needs. Once they proved successful, of course they were then used in the future! (See above.)
DAVID: You have solved the issue of speciation. It is simply adaptation.
dhw: It depends what kind of speciation you mean. I would say that larger brains and pelvises were indeed adaptations. (It is believed that there was interbreeding between different types of homos, and the ability to reproduce is one criterion for “species”). But it is sometimes difficult to draw a precise borderline between adaptation and innovation (e.g. pre-whale legs turning to flippers). However, I keep pointing out that evolutionary changes may be in the form of coping with new conditions (adaptation) and exploiting them (through innovations), and I would say that generally it is the latter that create clear speciation.
While I think God designs all future forms for future use.
Human evolution; savannah theory fading
Brain expansion
DAVID: Our only disagreement is how the new enlarged number of neurons arrived in sapiens. I'll stick with a designer God. But we have agreed the extra cells arrived new and unused in preparation for the future use.
We absolutely do NOT agree that the extra new cells were unused!!! That is the nub of our disagreement! You say your God popped in to insert new cells which would not be used for thousands and thousands of years – just as you believe that he turned pre-whales’ legs into flippers before they entered the water. The essence of your theories is God’s anticipation of events to come. (On the pelvis thread, you wrote: “I think God designs all future forms for future use”). My view is the exact opposite. The new sapiens brain cells would have been added to meet what was then a new requirement. They were needed. (If they had not been used, they would have become redundant – which was our agreed explanation for shrinkage, if shrinkage happened). But whereas in the past complexification reached its capacity and more new cells had to be added, in our case, complexification took over almost completely, and the existing, always useful cells were thus able to meet each new requirement as it arose.
DAVID: Lots of palaver about all those extra neurons 315,000 years ago, not used as they are now. Note in the caves there was little complicated for them to do. Certainly not reading, typing, deep conceptualizing as we do in our discussions.
Of course they were not used as they are used now! They enhanced their range of use as all these new requirements arose. But that does not mean they were not used before! The illiterate women’s existing brains complexified as a result of their learning to read, not in anticipation.
Cerebellum
DAVID: our large cerebellum, compared to other organisms is finally studied. It arrived 315,000 years ago and performs its duties, and we are now trying to find out how much it does for us.
dhw: Yes, the brain is a community of cell communities, just like the rest of the body, and they work together. And – to get back to the major disagreement which has dogged this discussion – you still haven’t explained why your God, who you agree designed a mechanism for autonomous complexification, could not possibly have designed a mechanism for autonomous enlargement.
DAVID: Same answer. You want secondhand design. Hands on design is more efficient, without question.
We have dealt with this before. When comparing yourself to God, you told us you had your plan when you wanted to design something, and of course it was more efficient for you to do your own designing. And I suggest that if your God’s only plan had been to design H. sapiens plus food, it would have been more efficient for him to mimic you and do it directly. But he didn’t. Unlike you, instead of directly designing the only things he wanted to design, he apparently fiddled around with countless life forms and foods – most of which had no connection with us and our foods – and then with one stage after another (the evolution of humans), designing some bits that were useful, discarding other bits that weren’t, until at long last he came up with the goods: you and me and our food. And you call this efficient? I suggest that he designed what he wanted to design, and that he actually wished for all those countless forms and foods and stages, as life unfolded its ever-changing variety. What better way than to give the original life forms their own means of designing? You agree that he gave brain cells an autonomous mechanism for complexification. And so once more, why couldn’t he possibly have given them the autonomous means of adding to their numbers?
Prehistoric brains and pelvises
DAVID: God set it up so new-sized infant heads fit into their mother's new-sized pelvises.
dhw: Two days ago, you said there would have been more deaths than in our time, because “obstetricians currently can solve more complications than cave folks back then. God did what he could to accommodate walking and big head birthing all at once.” Are you now saying there were no deaths at all? I suggest we drop this subject.
DAVID: Total misinterpretation of my statement. All it says is we can solve things now than they couldn't then.
It says “God set it up so new-sized infant heads fit into their mother’s new-sized pelvises.” You have agreed that there were probably more deaths then than now, so it seems that your God made a hash of it. Why won’t you drop this silly subject?
Human evolution; savannah theory fading
by David Turell , Tuesday, August 23, 2022, 16:09 (821 days ago) @ dhw
Brain expansion
DAVID: Our only disagreement is how the new enlarged number of neurons arrived in sapiens. I'll stick with a designer God. But we have agreed the extra cells arrived new and unused in preparation for the future use.
dhw: We absolutely do NOT agree that the extra new cells were unused!!! That is the nub of our disagreement! You say your God popped in to insert new cells which would not be used for thousands and thousands of years – just as you believe that he turned pre-whales’ legs into flippers before they entered the water. The essence of your theories is God’s anticipation of events to come. (On the pelvis thread, you wrote: “I think God designs all future forms for future use”). My view is the exact opposite. The new sapiens brain cells would have been added to meet what was then a new requirement. They were needed. (If they had not been used, they would have become redundant – which was our agreed explanation for shrinkage, if shrinkage happened). But whereas in the past complexification reached its capacity and more new cells had to be added, in our case, complexification took over almost completely, and the existing, always useful cells were thus able to meet each new requirement as it
arose.
It is preposterous to assume that huge new brain was fully used at its beginning. It is like an idling motor before driving off, functioning at a very low level before new uses begain:
DAVID: Lots of palaver about all those extra neurons 315,000 years ago, not used as they are now. Note in the caves there was little complicated for them to do. Certainly not reading, typing, deep conceptualizing as we do in our discussions.dhw: Of course they were not used as they are used now! They enhanced their range of use as all these new requirements arose. But that does not mean they were not used before! The illiterate women’s existing brains complexified as a result of their learning to read, not in anticipation.
The bold is the right way to view it. Minor use early, heavy use later.
CerebellumDAVID: our large cerebellum, compared to other organisms is finally studied. It arrived 315,000 years ago and performs its duties, and we are now trying to find out how much it does for us.
dhw: Yes, the brain is a community of cell communities, just like the rest of the body, and they work together. And – to get back to the major disagreement which has dogged this discussion – you still haven’t explained why your God, who you agree designed a mechanism for autonomous complexification, could not possibly have designed a mechanism for autonomous enlargement.
DAVID: Same answer. You want secondhand design. Hands on design is more efficient, without question.
We have dealt with this before. When comparing yourself to God, you told us you had your plan when you wanted to design something, and of course it was more efficient for you to do your own designing. And I suggest that if your God’s only plan had been to design H. sapiens plus food, it would have been more efficient for him to mimic you and do it directly. But he didn’t. Unlike you, instead of directly designing the only things he wanted to design, he apparently fiddled around with countless life forms and foods – most of which had no connection with us and our foods – and then with one stage after another (the evolution of humans), designing some bits that were useful, discarding other bits that weren’t, until at long last he came up with the goods: you and me and our food.
Simply a weak criticism of God's method of evolution to create us.
dhw: And you call this efficient? I suggest that he designed what he wanted to design, and that he actually wished for all those countless forms and foods and stages, as life unfolded its ever-changing variety. What better way than to give the original life forms their own means of designing? You agree that he gave brain cells an autonomous mechanism for complexification. And so once more, why couldn’t he possibly have given them the autonomous means of adding to their numbers?
Back to secondhand design. Not worth the trouble it presents. covered before.
Human evolution; savannah theory fading
Brain expansion
DAVID: Our only disagreement is how the new enlarged number of neurons arrived in sapiens. I'll stick with a designer God. But we have agreed the extra cells arrived new and unused in preparation for the future use.
dhw: We absolutely do NOT agree that the extra new cells were unused!!! That is the nub of our disagreement! You say your God popped in to insert new cells which would not be used for thousands and thousands of years – just as you believe that he turned pre-whales’ legs into flippers before they entered the water. The essence of your theories is God’s anticipation of events to come. (On the pelvis thread, you wrote: “I think God designs all future forms for future use”). My view is the exact opposite. The new sapiens brain cells would have been added to meet what was then a new requirement. They were needed. (If they had not been used, they would have become redundant – which was our agreed explanation for shrinkage, if shrinkage happened). But whereas in the past complexification reached its capacity and more new cells had to be added, in our case, complexification took over almost completely, and the existing, always useful cells were thus able to meet each new requirement as it arose.
DAVID: It is preposterous to assume that huge new brain was fully used at its beginning.
Why have you inserted the word “fully”? Of course it’s preposterous. The brain can never be “fully” used – unless you think there will never be any more new ideas or conditions for the rest of time! I dispute your claim that the new cells were not used when they arrived but simply sat around for a few thousand years doing nothing. I find it “preposterous” to assume that new cells were added without any need for them at the time. I propose that they were needed and used to meet a new requirement, and have continued to be used ever since, complexifying as they and their buddies continue to meet new requirements. (But if shrinkage occurred, complexification proved so efficient that some previously useful cells became redundant).
DAVID: Lots of palaver about all those extra neurons 315,000 years ago, not used as they are now. Note in the caves there was little complicated for them to do. Certainly not reading, typing, deep conceptualizing as we do in our discussions.
dhw: Of course they were not used as they are used now! They enhanced their range of use as all these new requirements arose. But that does not mean they were not used before![/i] […]
DAVID: The bold is the right way to view it. Minor use early, heavy use later.
We agree. They did NOT arrive “unused in preparation for the future use”, but were used right from the start. And I extend this principle to the whole of evolution: changes do not take place in anticipation of future requirements but as a response to current new requirements.
Cerebellum
dhw: […] you still haven’t explained why your God, who you agree designed a mechanism for autonomous complexification, could not possibly have designed a mechanism for autonomous enlargement.
DAVID: Same answer. You want secondhand design. Hands on design is more efficient, without question.
dhw: We have dealt with this before. When comparing yourself to God, you told us you had your plan when you wanted to design something, and of course it was more efficient for you to do your own designing. And I suggest that if your God’s only plan had been to design H. sapiens plus food, it would have been more efficient for him to mimic you and do it directly. But he didn’t. Unlike you, instead of directly designing the only things he wanted to design, he apparently fiddled around with countless life forms and foods – most of which had no connection with us and our foods – and then with one stage after another (the evolution of humans), designing some bits that were useful, discarding other bits that weren’t, until at long last he came up with the goods: you and me and our food.
DAVID: Simply a weak criticism of God's method of evolution to create us.
It is not a criticism of God! It is a criticism of your theory that his one and only purpose was to create us and our food! The history of life does not reveal the single-minded pursuit of a single purpose which characterized your own form of design and made direct action the most efficient way of achieving your goal.
dhw: I suggest that he designed what he wanted to design, and that he actually wished for all those countless forms and foods and stages, as life unfolded its ever-changing variety. What better way than to give the original life forms their own means of designing? You agree that he gave brain cells an autonomous mechanism for complexification. And so once more, why couldn’t he possibly have given them the autonomous means of adding to their numbers?
DAVID: Back to secondhand design. Not worth the trouble it presents. covered before.
Still you refuse to answer my question, now bolded. The silly “secondhand” argument, in which you modestly compared yourself to God, has been dealt with above, and you have simply ignored it.
Human evolution; new Australopithecus dating
by David Turell , Wednesday, August 24, 2022, 15:02 (820 days ago) @ dhw
From the south African Sterkfontein caves:
https://www.the-scientist.com/news-opinion/south-african-hominin-fossils-predate-lucy-a...
"A newer dating technique using cosmogenic isotopes finds Australopithecus remains from the Sterkfontein caves to be about 1 million years older than previous estimates, potentially changing scientists’ understanding of humanity’s origins.
"Remains of ancient Australopithecus hominins from the Sterkfontein caves in South Africa—including the well-known “Mrs. Ples”—were originally dated to between 2.1 and 2.6 million years ago, but they are actually between 3.4 and 3.6 million years old, a study estimates. The revised dates, published in PNAS on Monday (June 27), would mean they’re older than the famous Lucy fossil unearthed in Ethiopia, which is dated to around 3.2 million years ago,
***
"The archeological community has widely accepted the hypothesis that the early hominin species Australopithecus africanus (e.g. Mrs. Ples) descended from A. afarensis (e.g. Lucy). However, “[t]he contemporaneity of the two species now suggests that a more complex family tree prevailed early in the human evolutionary process,” the study authors write.
***
"In East Africa, volcanic ash surrounding fossils can be used for accurate dating, according to Purdue’s news release, but it’s more complicated in South Africa. There, researchers have had to use surrounding animal fossils, which can shift over time, or calcite flowstone deposits, which can settle in areas older than them, leading to underestimates of age. The current analysis employed a newer technique instead, one that directly ages the surrounding sediment. Using mass spectrometry, the researchers measured cosmogenic isotopes in quartz excavated from around the fossils; the relative decay of these elements reveals how old the rocks are.
“'South Africa was largely ignored because it was so difficult to date the fossils. They were largely dismissed as not being relevant to the story of human evolution,” study coauthor Ronald Clarke tells The Sydney Morning Herald. “It’s a big deal, this does confirm that these primitive ancestors were all over Africa."
Comment: when Australopithecus appeared it apparently was all over Africa. All the other subsequent hominins descend from them. So our roots were wider spread than realized.
Human evolution; savannah theory fading
by David Turell , Wednesday, August 24, 2022, 15:53 (820 days ago) @ dhw
Brain expansion
DAVID: It is preposterous to assume that huge new brain was fully used at its beginning.
dhw: Why have you inserted the word “fully”? Of course it’s preposterous. The brain can never be “fully” used – unless you think there will never be any more new ideas or conditions for the rest of time! I dispute your claim that the new cells were not used when they arrived but simply sat around for a few thousand years doing nothing. I find it “preposterous” to assume that new cells were added without any need for them at the time. I propose that they were needed and used to meet a new requirement, and have continued to be used ever since, complexifying as they and their buddies continue to meet new requirements. (But if shrinkage occurred, complexification proved so efficient that some previously useful cells became redundant).
Thank you for admitting the new 315,000-old neurons still have future use. That is the whole point: they existed for tiny uses back then with a capacity for our now huge uses. What prepared them for them for an unknown future? Not Darwin theory, which handles only the present. Logical to assume God, the designer set up teh brain for the future.
DAVID: The bold is the right way to view it. Minor use early, heavy use later.dhw: We agree. They did NOT arrive “unused in preparation for the future use”, but were used right from the start. And I extend this principle to the whole of evolution: changes do not take place in anticipation of future requirements but as a response to current new requirements.
We do not agree at all based on this new revision from you.
CerebellumDAVID: Simply a weak criticism of God's method of evolution to create us.
dhw: It is not a criticism of God! It is a criticism of your theory that his one and only purpose was to create us and our food! The history of life does not reveal the single-minded pursuit of a single purpose which characterized your own form of design and made direct action the most efficient way of achieving your goal.
God's direct action at the end was to produce humans, so unusual Adler uses us as proof of God. From the beginning of time God knew we were coming!!! That answers your muddle about evolution which God used as His mechanism to create us.
dhw: I suggest that he designed what he wanted to design, and that he actually wished for all those countless forms and foods and stages, as life unfolded its ever-changing variety. What better way than to give the original life forms their own means of designing? You agree that he gave brain cells an autonomous mechanism for complexification. And so once more, why couldn’t he possibly have given them the autonomous means of adding to their numbers?DAVID: Back to secondhand design. Not worth the trouble it presents. covered before.
dw: Still you refuse to answer my question, now bolded. The silly “secondhand” argument, in which you modestly compared yourself to God, has been dealt with above, and you have simply ignored it.
Answered above
Human evolution; savannah theory fading
Brain expansion
DAVID: It is preposterous to assume that huge new brain was fully used at its beginning.
dhw: Why have you inserted the word “fully”? Of course it’s preposterous. The brain can never be “fully” used – unless you think there will never be any more new ideas or conditions for the rest of time! I dispute your claim that the new cells were not used when they arrived but simply sat around for a few thousand years doing nothing. I find it “preposterous” to assume that new cells were added without any need for them at the time. I propose that they were needed and used to meet a new requirement, and have continued to be used ever since, complexifying as they and their buddies continue to meet new requirements.[/b] (But if shrinkage occurred, complexification proved so efficient that some previously useful cells became redundant).
DAVID: Thank you for admitting the new 315,000-old neurons still have future use.
All successful evolutionary changes have future use! They wouldn’t survive if they didn’t!
DAVID: That is the whole point: they existed for tiny uses back then with a capacity for our now huge uses.
You initially claimed that they had no use but just sat around for thousands of years doing nothing. You then conceded that they may have had minor uses. THAT is the whole point. Your theory is that God popped them into the brains of some sleeping Moroccans so that thousands of years later, they would be useful. My theory is bolded above.
DAVID: What prepared them for them for an unknown future? Not Darwin theory, which handles only the present. Logical to assume God, the designer set up teh brain for the future.
The future is unknown for ALL life forms! According to you, every evolutionary change was engineered by God as preparation for the unknown future. You even have him transforming pre-whale legs into flippers before the animals enter the water. My proposal (why must you bring Darwin into it?) is that every evolutionary change, including the additional brain cells, has resulted from a new current requirement or opportunity presented by changing conditions. NOT from your God’s gazing into his crystal ball and forecasting all future requirements. But of course the additional cells will continue to be used and to complexify in response to new future requirements!
DAVID: The bold is the right way to view it. Minor use early, heavy use later.
dhw: We agree. They did NOT arrive “unused in preparation for the future use”, but were used right from the start.
DAVID: We do not agree at all based on this new revision from you.
What “new revision”? This is the theory I have presented all along. The only revision in the context of the extra brain cells has been yours: from no use at all to minor use. Now would you please tell us why you think it impossible for your God to have given brain cells the same autonomy for adding to their numbers as he apparently gave them for complexification. Your reply to this yesterday was:
DAVID: Back to secondhand design. Not worth the trouble it presents. covered before.
This is not an answer, but I had already covered the silly “secondhand” argument, which you repeat on the “More miscellany thread”, and so I have reproduced the discussion there.
DAVID: God's direct action at the end was to produce humans, so unusual Adler uses us as proof of God.
It was not direct. You yourself cannot understand why “at the end” he would have designed various “species” of hominin and homo before finally designing sapiens. That is one of the theories that “make sense only to God”. Yes, you keep telling us that Adler uses us as proof of God. But we are not arguing about proof of God. We are arguing about your theories of evolution which do not make sense to you.
DAVID: From the beginning of time God knew we were coming!!! That answers your muddle about evolution which God used as His mechanism to create us.
I have covered the hypothesis that from the beginning he “knew we were coming” (or we were his purpose) by explaining all the disconnected life forms and food bushes which you cannot explain as experiments in his quest to create beings that might recognize him and have a relationship with him (your own concept). But you don’t like the theory because it entails “human” attributes which are not among those you want your God to have.
dhw: I suggest that he designed what he wanted to design, and that he actually wished for all those countless forms and foods and stages, as life unfolded its ever-changing variety. What better way than to give the original life forms their own means of designing?
DAVID: Answered above.
Again with your “secondhand” objection. See “More miscellany”.
Human evolution; first walking ancestor
by David Turell , Thursday, August 25, 2022, 22:21 (819 days ago) @ dhw
Seven million years ago:
https://www.livescience.com/when-human-ancestors-first-walked-upright?utm_campaign=368B...
"The oldest known human-like species likely walked on two legs as far back as 7 million years ago, a new study finds, and the discovery sheds light on what first set humans apart from our ape relatives.
"Researchers analyzed a thigh bone (femur) and a pair of forearm bones (ulnae) from Sahelanthropus tchadensis, which may be the oldest known hominin — a relative of humans dating from after our ancestors split from those of modern apes — according to the Smithsonian National Museum of Natural History(opens in new tab). First unearthed in Chad in north central Africa in 2001, the remains are about 7 million years old.
"The examination of the femur and ulnae indicated that S. tchadensis not only walked on two feet but also climbed trees, adding evidence that this enigmatic species was bipedal, as an earlier analysis of its skull anatomy suggested.
***
"The partial skull of S. tchadensis that the scientists found revealed that the species was probably close to a chimpanzee in size and structure. Although its brain also appeared chimp-size, its face and teeth more closely resembled those of hominins, suggesting it may have been a close relative of the last common ancestor of humans and chimps, the researchers said.
"Judging by the thick, prominent brow ridges of the skull, the specimen, which the researchers nicknamed "Toumaï," was probably male.
***
"Perhaps the most interesting feature that Toumaï shares with other hominins is the anatomy of the opening at the base of the skull where the spinal cord emerges. In four-legged animals, this opening is normally located toward the back of the skull and is oriented backward. However, in S. tchadensis, this opening is positioned near the middle of the skull and is oriented downward. This suggests that S. tchadensis was bipedal, meaning it walked on two legs, Daniel Lieberman, a human evolutionary biologist at Harvard University...
***
"'Our study shows that the Chadian species has a set of selected anatomical features that clearly indicate that our oldest known representatives were practicing bipedalism, on the ground and on the trees," study co-author Franck Guy, a paleoanthropologist at the University of Poitiers in France, told Live Science.
***
"All in all, "the key finding is that the earliest hominins were bipeds of some sort, reinforcing the evidence that the evolution of bipedalism is what set the human lineage on a separate path from the apes," Lieberman said in the email. "But, like our closest living chimpanzee relatives, early hominins still retained abilities to climb trees.'"
Comment: the driving force for these early hominins was for terrestrial walking. There is no obvious natural driving need for this, so why did it happen? Apes and monkeys have continued to this day happily in an arboreal existance. Why did some folks try to switch? Or did God design the change?
Human evolution; savannah theory fading
by David Turell , Friday, August 26, 2022, 00:26 (819 days ago) @ dhw
Brain expansion
DAVID: Thank you for admitting the new 315,000-old neurons still have future use.
dhw: You initially claimed that they had no use but just sat around for thousands of years doing nothing. You then conceded that they may have had minor uses. THAT is the whole point. Your theory is that God popped them into the brains of some sleeping Moroccans so that thousands of years later, they would be useful. My theory is bolded above.
We agree therev= was minor use before major uses. Tehyc would not survive if unused, this is obvious. You unreasonably assumed I assumed no use at all until later.
DAVID: What prepared them for them for an unknown future? Not Darwin theory, which handles only the present. Logical to assume God, the designer set up teh brain for the future.dhw: The future is unknown for ALL life forms! According to you, every evolutionary change was engineered by God as preparation for the unknown future. You even have him transforming pre-whale legs into flippers before the animals enter the water. My proposal (why must you bring Darwin into it?) is that every evolutionary change, including the additional brain cells, has resulted from a new current requirement or opportunity presented by changing conditions. NOT from your God’s gazing into his crystal ball and forecasting all future requirements. But of course the additional cells will continue to be used and to complexify in response to new future requirements!
Well, I'm still with God the future designer and you're not. No surprise.
DAVID: God's direct action at the end was to produce humans, so unusual Adler uses us as proof of God.dhw: It was not direct. You yourself cannot understand why “at the end” he would have designed various “species” of hominin and homo before finally designing sapiens. That is one of the theories that “make sense only to God”. Yes, you keep telling us that Adler uses us as proof of God. But we are not arguing about proof of God. We are arguing about your theories of evolution which do not make sense to you.
And proof of God is part of it. Adler helps my arguments.
DAVID: From the beginning of time God knew we were coming!!! That answers your muddle about evolution which God used as His mechanism to create us.dhw: I have covered the hypothesis that from the beginning he “knew we were coming” (or we were his purpose) by explaining all the disconnected life forms and food bushes which you cannot explain as experiments in his quest to create beings that might recognize him and have a relationship with him (your own concept). But you don’t like the theory because it entails “human” attributes which are not among those you want your God to have.
You are again trying to humanize my God to protect your form of god.
dhw: I suggest that he designed what he wanted to design, and that he actually wished for all those countless forms and foods and stages, as life unfolded its ever-changing variety. What better way than to give the original life forms their own means of designing?DAVID: Answered above.
dhw: Again with your “secondhand” objection. See “More miscellany”.
Secondhand design is a cumbersome mess, that you don't seem to understand. You've never tried it and I have with firsthand experience
Human evolution; savannah theory fading
Brain expansion
DAVID: Thank you for admitting the new 315,000-old neurons still have future use.
dhw: You initially claimed that they had no use but just sat around for thousands of years doing nothing. You then conceded that they may have had minor uses. [...]
DAVID: We agree there was minor use before major uses. They would not survive if unused, this is obvious. You unreasonably assumed I assumed no use at all until later.
Initially you argued that the brain was oversized and the new neurons were “excess” (which = not needed). Anyway, we needn’t argue about that now, since you have agreed that the new cells were used from the start.
DAVID: What prepared them for them for an unknown future? Not Darwin theory, which handles only the present. Logical to assume God, the designer set up teh brain for the future.
dhw: The future is unknown for ALL life forms! According to you, every evolutionary change was engineered by God as preparation for the unknown future. You even have him transforming pre-whale legs into flippers before the animals enter the water. My proposal (why must you bring Darwin into it?) is that every evolutionary change, including the additional brain cells, has resulted from a new current requirement or opportunity presented by changing conditions. NOT from your God’s gazing into his crystal ball and forecasting all future requirements. But of course the additional cells will continue to be used and to complexify in response to new future requirements!
DAVID: Well, I'm still with God the future designer and you're not. No surprise.
Are you still with God as a designer who operates on brains to provide them with excess additional cells before they are needed, and on whales to provide them with flippers before they enter the water?
DAVID: God's direct action at the end was to produce humans, so unusual Adler uses us as proof of God.
dhw: It was not direct. You yourself cannot understand why “at the end” he would have designed various “species” of hominin and homo before finally designing sapiens. That is one of the theories that “make sense only to God”. Yes, you keep telling us that Adler uses us as proof of God. But we are not arguing about proof of God. We are arguing about your theories of evolution which do not make sense to you.
DAVID: And proof of God is part of it. Adler helps my arguments.
You don’t need to “prove” God if you wish to argue that God’s one and only aim was to design us and our food, but you don’t know why he designed countless species and foods that had no connection with us, or why he designed us in itsy-bitsy stages instead of directly. All you need to do is admit that your theory “makes sense only to God” and therefore it does not make sense to you.
DAVID: From the beginning of time God knew we were coming!!! That answers your muddle about evolution which God used as His mechanism to create us.
dhw: I have covered the hypothesis that from the beginning he “knew we were coming” (or we were his purpose) by explaining all the disconnected life forms and food bushes which you cannot explain as experiments in his quest to create beings that might recognize him and have a relationship with him (your own concept). But you don’t like the theory because it entails “human” attributes which are not among those you want your God to have.
DAVID: You are again trying to humanize my God to protect your form of god.
“Protect”? The experimenting alternative offers you a logical explanation for YOUR theory which otherwise doesn’t make sense to you!
dhw: I suggest that he designed what he wanted to design, and that he actually wished for all those countless forms and foods and stages, as life unfolded its ever-changing variety. What better way than to give the original life forms their own means of designing?
DAVID: Answered above.
dhw: Again with your “secondhand” objection. See “More miscellany”.
DAVID: Secondhand design is a cumbersome mess, that you don't seem to understand. You've never tried it and I have with firsthand experience.
Please stop comparing yourself to God. I have given you an answer on the “More miscellany” thread.
Human evolution; savannah theory fading
by David Turell , Friday, August 26, 2022, 16:37 (818 days ago) @ dhw
Brain expansion
DAVID: Well, I'm still with God the future designer and you're not. No surprise.
dhw: Are you still with God as a designer who operates on brains to provide them with excess additional cells before they are needed, and on whales to provide them with flippers before they enter the water?
The oversized brain study is now reputed.
DAVID: God's direct action at the end was to produce humans, so unusual Adler uses us as proof of God.dhw: It was not direct. You yourself cannot understand why “at the end” he would have designed various “species” of hominin and homo before finally designing sapiens. That is one of the theories that “make sense only to God”. Yes, you keep telling us that Adler uses us as proof of God. But we are not arguing about proof of God. We are arguing about your theories of evolution which do not make sense to you.
DAVID: And proof of God is part of it. Adler helps my arguments. They all make perfect sense to me. if not to you in your weird pattern of thoughts about your 'possible' God.
dhw: You don’t need to “prove” God if you wish to argue that God’s one and only aim was to design us and our food, but you don’t know why he designed countless species and foods that had no connection with us, or why he designed us in itsy-bitsy stages instead of directly. All you need to do is admit that your theory “makes sense only to God” and therefore it does not make sense to you.
God chose to evolve us in itsy-bitsy stages is a perfect logical conclusion, but He never revealed why He chose that methodology.
DAVID: From the beginning of time God knew we were coming!!! That answers your muddle about evolution which God used as His mechanism to create us.dhw: I have covered the hypothesis that from the beginning he “knew we were coming” (or we were his purpose) by explaining all the disconnected life forms and food bushes which you cannot explain as experiments in his quest to create beings that might recognize him and have a relationship with him (your own concept). But you don’t like the theory because it entails “human” attributes which are not among those you want your God to have.
DAVID: You are again trying to humanize my God to protect your form of god.
dhw: “Protect”? The experimenting alternative offers you a logical explanation for YOUR theory which otherwise doesn’t make sense to you!'
It all makes perfect sense from the way I view God, and you don't.
dhw: I suggest that he designed what he wanted to design, and that he actually wished for all those countless forms and foods and stages, as life unfolded its ever-changing variety. What better way than to give the original life forms their own means of designing?DAVID: Answered above.
dhw: Again with your “secondhand” objection. See “More miscellany”.
DAVID: Secondhand design is a cumbersome mess, that you don't seem to understand. You've never tried it and I have with firsthand experience.
dhw: Please stop comparing yourself to God. I have given you an answer on the “More miscellany” thread.
I'm not comparing to God. I am discussing how designing works from my design background, and you know it!!! Stop distorting!!!
Human evolution; savannah theory fading
Brain expansion
DAVID: Well, I'm still with God the future designer and you're not. No surprise.
dhw: Are you still with God as a designer who operates on brains to provide them with excess additional cells before they are needed, and on whales to provide them with flippers before they enter the water?
DAVID: The oversized brain study is now reputed.
And your theory that the new sapiens cells were “excess” is therefore also repudiated. And you still haven't told us why your God was able to give cells the autonomous ability to complexify, but didn't or couldn't give them the autonomous ability to add to their number when necessary.
The rest of this post should be under the heading of David’s theory of evolution, but we’ll leave it here for now.
DAVID: God's direct action at the end was to produce humans, so unusual Adler uses us as proof of God.
dhw: It was not direct. You yourself cannot understand why “at the end” he would have designed various “species” of hominin and homo before finally designing sapiens. That is one of the theories that “make sense only to God”. Yes, you keep telling us that Adler uses us as proof of God. But we are not arguing about proof of God. We are arguing about your theories of evolution which do not make sense to you.
DAVID: And proof of God is part of it. Adler helps my arguments. They all make perfect sense to me. if not to you in your weird pattern of thoughts about your 'possible' God.
dhw: You don’t need to “prove” God if you wish to argue that God’s one and only aim was to design us and our food, but you don’t know why he designed countless species and foods that had no connection with us, or why he designed us in itsy-bitsy stages instead of directly. All you need to do is admit that your theory “makes sense only to God” and therefore it does not make sense to you.
DAVID: God chose to evolve us in itsy-bitsy stages is a perfect logical conclusion, but He never revealed why He chose that methodology.
It is a fact that we evolved in itsy-bitsy stages. It is not a fact that we (plus our food) were your God's one and only purpose, and it is not perfectly logical that an all-powerful God with one purpose in mind should first design countless life forms that had nothing to do with his purpose, or that he should have “chosen” to evolve us in stages although, according to you, he had the power to design life forms with no precursors. He has never revealed his choice of purpose or method to anyone – even if he exists – and since you can’t explain your theory about his purpose and method, you can hardly call it “perfectly logical”.
DAVID: From the beginning of time God knew we were coming!!! That answers your muddle about evolution which God used as His mechanism to create us.
dhw: I have covered the hypothesis that from the beginning he “knew we were coming” (or we were his purpose) by explaining all the disconnected life forms and food bushes which you cannot explain as experiments in his quest to create beings that might recognize him and have a relationship with him (your own concept). But you don’t like the theory because it entails “human” attributes which are not among those you want your God to have.
DAVID: You are again trying to humanize my God to protect your form of god.
dhw: “Protect”? The experimenting alternative offers you a logical explanation for YOUR theory which otherwise doesn’t make sense to you!'
DAVID: It all makes perfect sense from the way I view God, and you don't.
The way you view God is that he had one purpose, and you have no idea why he chose to fulfil his purpose in the manner you propose. Your proposal “makes sense only to God”, and yet you insist that it makes sense to you. Are you God? 
dhw: I suggest that he designed what he wanted to design, and that he actually wished for all those countless forms and foods and stages, as life unfolded its ever-changing variety. What better way than to give the original life forms their own means of designing?
DAVID: Answered above.
dhw: Again with your “secondhand” objection. […]
DAVID: Secondhand design is a cumbersome mess, that you don't seem to understand. You've never tried it and I have with firsthand experience.
dhw: Please stop comparing yourself to God.
DAVID: I'm not comparing to God. I am discussing how designing works from my design background, and you know it!!! Stop distorting!!!
You are comparing your method of design to God’s, and it is a total mismatch. You have one plan, and you implement it directly. Then you say that is the efficient way to do it, and so he would not have “delegated” design to other minds (intelligent cells). But although you say that like you, your God had one plan, he did NOT implement it directly! He designed countless life forms that had no connection with his “plan”, and he did not even design his “endpoint” (sapiens) directly, but did countless twiddles before finally getting rid of all the irrelevant twiddles and hominins and homos that were not sapiens. It is all the diversions from your proposed “plan” that (a) you cannot explain, and (b) suggest he is not a Turell, and (c) are logically explained by my alternative theories.
Human evolution; savannah theory fading
by David Turell , Saturday, August 27, 2022, 16:16 (817 days ago) @ dhw
Brain expansion
DAVID: God chose to evolve us in itsy-bitsy stages is a perfect logical conclusion, but He never revealed why He chose that methodology.
dhw: It is a fact that we evolved in itsy-bitsy stages. It is not a fact that we (plus our food) were your God's one and only purpose, and it is not perfectly logical that an all-powerful God with one purpose in mind should first design countless life forms that had nothing to do with his purpose, or that he should have “chosen” to evolve us in stages although, according to you, he had the power to design life forms with no precursors. He has never revealed his choice of purpose or method to anyone – even if he exists – and since you can’t explain your theory about his purpose and method, you can hardly call it “perfectly logical”.
The 'countless life forms' created the disappearing food web discussed in the other thread.
DAVID: You are again trying to humanize my God to protect your form of god.dhw: “Protect”? The experimenting alternative offers you a logical explanation for YOUR theory which otherwise doesn’t make sense to you!'
DAVID: It all makes perfect sense from the way I view God, and you don't.
dhw: The way you view God is that he had one purpose, and you have no idea why he chose to fulfil his purpose in the manner you propose. Your proposal “makes sense only to God”, and yet you insist that it makes sense to you. Are you God?
I'm not God but my God makes perfect sense to me.
dhw: I suggest that he designed what he wanted to design, and that he actually wished for all those countless forms and foods and stages, as life unfolded its ever-changing variety. What better way than to give the original life forms their own means of designing?DAVID: Answered above.
dhw: Again with your “secondhand” objection. […]
DAVID: Secondhand design is a cumbersome mess, that you don't seem to understand. You've never tried it and I have with firsthand experience.
dhw: Please stop comparing yourself to God.
DAVID: I'm not comparing to God. I am discussing how designing works from my design background, and you know it!!! Stop distorting!!!
dhw: You are comparing your method of design to God’s, and it is a total mismatch. You have one plan, and you implement it directly. Then you say that is the efficient way to do it, and so he would not have “delegated” design to other minds (intelligent cells). But although you say that like you, your God had one plan, he did NOT implement it directly! He designed countless life forms that had no connection with his “plan”, and he did not even design his “endpoint” (sapiens) directly, but did countless twiddles before finally getting rid of all the irrelevant twiddles and hominins and homos that were not sapiens. It is all the diversions from your proposed “plan” that (a) you cannot explain, and (b) suggest he is not a Turell, and (c) are logically explained by my alternative theories.
God's creation pattern is to evolve all forms stepwise: the universe from the BB, the
Earth from its origin, life from its start to final sapiens from Erectus, etc. It is perfectly obvious pattern. Your point now bolded is refuted by the studies I have quoted.
Human evolution; a mosaic development:
by David Turell , Monday, July 18, 2022, 20:13 (857 days ago) @ dhw
Recent genetic studies of several differing fossil specimens:
https://phys.org/news/2022-07-genetic-variations-human-emerge.html
"The results, published in the journal Scientific Reports, show two moments in which mutations accumulated: one around 40,000 years ago, associated with the growth of the Homo sapiens population and its departure from Africa, and an older one, more than 100,000 years ago, related to the time of the greatest diversity of types of Homo sapiens in Africa.
"However, it is difficult to determine when the genetic variants that distinguish us from other human species emerged. In this study, we have placed species-specific variants on a timeline. We have discovered how these variants accumulate over time, reflecting events such as the point of divergence between Homo sapiens and other human species around 100,000 years ago," says Alejandro Andirkó, first author of this article, which was part of his doctoral thesis at the UB.
***
"The results of the research study also show differences between evolutionary periods. Specifically, they highlight the predominance of genetic variants related to behavior and facial structure—key characteristics in the differentiation of our species from other human species—more than 300,000 years ago, a date that coincides with the available fossil and archaeological evidence. "We have discovered sets of genetic variants which affect the evolution of the face and which we have dated between 300,000 and 500,000 years ago, the period just prior to the dating of the earliest fossils of our species, such as the ones discovered at the Jebel Irhoud archaeological site in Morocco," notes Andirkó. (my bold)
"The researchers also analyzed variants related to the brain, the organ that can best help explain key features of the rich repertoire of behaviors associated with Homo sapiens. Specifically, they dated variants which medical studies conducted in present-day humans have linked to the volume of the cerebellum, corpus callosum and other structures. "We found that brain tissues have a particular genomic expression profile at different times in our history; that is, certain genes related to neural development were more highly expressed at certain times," says the researcher.
"These results complement an idea that is dominant in evolutionary anthropology: that there is no linear history of human species, but that different branches of our evolutionary tree coexisted and often intersected. "The breadth of the range of human diversity in the past has surprised anthropologists. Even within Homo sapiens there are fossils, such as the ones I mentioned earlier from Jebel Irhoud, which, because of their features, were thought to belong to another species. That's why we say that human beings have lived a mosaic evolution," he notes". (my bold)
Comment: dhw has always wondered why so many types of pre-sapiens were evolved. Well, this study shows exactly that is what happened. We are the result of a mosaic of potential final forms. dhw will wonder why God chose that method, and my obvious answer from the way I understand how to think about God, is that is the way God planned to do it for His own reasons. There is no reason to try to dig any deeper, but in dhw's confused way he will make an attempt.
Human evolution; a mosaic development:
QUOTE: "These results complement an idea that is dominant in evolutionary anthropology: that there is no linear history of human species, but that different branches of our evolutionary tree coexisted and often intersected. "The breadth of the range of human diversity in the past has surprised anthropologists. Even within Homo sapiens there are fossils, such as the ones I mentioned earlier from Jebel Irhoud, which, because of their features, were thought to belong to another species. That's why we say that human beings have lived a mosaic evolution," he notes". (David’s bold)
DAVID: dhw has always wondered why so many types of pre-sapiens were evolved. Well, this study shows exactly that is what happened.
I am not questioning that this happened! I ask why a God whose one and only purpose was to design H. sapiens plus food proceeded to design all sort of life forms unconnected with H. sapiens plus food, and also designed all sorts of hominins and homos and then discarded them, although he was apparently perfectly capable of designing new species with no precursors (Cambrian).
DAVID: We are the result of a mosaic of potential final forms. dhw will wonder why God chose that method, and my obvious answer from the way I understand how to think about God, is that is the way God planned to do it for His own reasons.
Precisely. You have no idea why he would have chosen such a method in order to achieve the purpose you have assigned to him – your theories “make sense only to God” and therefore not to you.
DAVID: There is no reason to try to dig any deeper, but in dhw's confused way he will make an attempt.
You would obviously prefer not to dig any deeper, since you regard your own theory as non-sense. I don’t know why you regard my logical alternatives as “confused”, since it is you who can find no explanation for the bolded theory above (which “makes sense only to God”). As you have agreed, the above historical facts would fit in perfectly with the theory that if God did it all, he was experimenting – but no, you can’t accept that a God who certainly/probably/possibly has thought patterns in common with those of his creations could have such thought patterns in common with those of his creations.
In case it gets overlooked, I'd just like to repeat my request for your views on WHY your all-purposeful God might have set out with the one and only purpose of designing H. sapiens (plus food)
Human evolution; a mosaic development:
by David Turell , Tuesday, July 19, 2022, 20:51 (856 days ago) @ dhw
QUOTE: "These results complement an idea that is dominant in evolutionary anthropology: that there is no linear history of human species, but that different branches of our evolutionary tree coexisted and often intersected. "The breadth of the range of human diversity in the past has surprised anthropologists. Even within Homo sapiens there are fossils, such as the ones I mentioned earlier from Jebel Irhoud, which, because of their features, were thought to belong to another species. That's why we say that human beings have lived a mosaic evolution," he notes". (David’s bold)
DAVID: dhw has always wondered why so many types of pre-sapiens were evolved. Well, this study shows exactly that is what happened.
dhw: I am not questioning that this happened! I ask why a God whose one and only purpose was to design H. sapiens plus food proceeded to design all sort of life forms unconnected with H. sapiens plus food, and also designed all sorts of hominins and homos and then discarded them, although he was apparently perfectly capable of designing new species with no precursors (Cambrian).
God simply follows the designs that He felt were necessary. You constantly overanalyze what God has done for His own reasons. You can't outthink Him!!
DAVID: We are the result of a mosaic of potential final forms. dhw will wonder why God chose that method, and my obvious answer from the way I understand how to think about God, is that is the way God planned to do it for His own reasons.dhw: Precisely. You have no idea why he would have chosen such a method in order to achieve the purpose you have assigned to him – your theories “make sense only to God” and therefore not to you.
It makes perfect sense to accept what God does as His perfect choice for creation.
DAVID: There is no reason to try to dig any deeper, but in dhw's confused way he will make an attempt.dhw: You would obviously prefer not to dig any deeper, since you regard your own theory as non-sense. I don’t know why you regard my logical alternatives as “confused”, since it is you who can find no explanation for the bolded theory above (which “makes sense only to God”). As you have agreed, the above historical facts would fit in perfectly with the theory that if God did it all, he was experimenting – but no, you can’t accept that a God who certainly/probably/possibly has thought patterns in common with those of his creations could have such thought patterns in common with those of his creations.
Back we go to your humanized God who must in a human=like way experiment.
dhw: In case it gets overlooked, I'd just like to repeat my request for your views on WHY your all-purposeful God might have set out with the one and only purpose of designing H. sapiens (plus food)
We have all guessed at His reasons repeatedly. He gave us brains so we could debate about Him. So we recognize Him. That much can be said with confidence.
Human evolution; our complex speech mechanism
by David Turell , Tuesday, December 04, 2018, 18:09 (2179 days ago) @ dhw
dhw: The start of our solar system and Planet Earth was pretty major for you and me, but an eternal and infinite universe could have had an infinite number of major starts.
DAVID: Up to this point we were talking about possibilities with significant evidence. The eternal and infinite universe is pure hypothesis and without a smidgen of evidence.
dhw: Fair comment. I should have stuck to our solar system and planet. Apologies for taking us off onto a different track. An interesting one, though. One has to ask: what was there before the Big Bang, if it ever happened? Nothing at all is also pure hypothesis, as is an eternal mind without a beginning. There is no way we shall ever know, unless your pure hypothesis is correct and your God reveals himself!
DAVID: According to Guth and his cohorts there is no 'before' before the Big Bang, proven mathematically in a paper presented in 2002 at Hawkings 60th birthday party/ symposium, my book, page 63. Put simply, time starts with the BB. Just as life starts with the first functional living cell. Both starts are followed by an evolutionary process which are too complex to be the result of chance. If there is a cause for each event, it is simpler to attribute them to one source than to conjure up two causes for two such pivotal creations.
dhw: A strange volte face. According to you, your God caused the BB, and so he existed before the BB. Before, now and after are one concept of time. Nobody can possibly prove anything about what happened before the BB (if it happened). I agree that one cause is simpler than two causes. The one cause may be an eternal and infinite universe of energy and matter constantly changing itself. No, I don’t believe it, and I don’t disbelieve it, just as I don’t believe or disbelieve in a single, conscious, sourceless, eternal mind. Maybe the complex evolutionary process was created (top down), or maybe it evolved (bottom up).
All I presented has appeared here before. If bottom up, from what, and what pushed it to evolve?
Human evolution; our complex speech mechanism
DAVID: According to Guth and his cohorts there is no 'before' before the Big Bang, proven mathematically in a paper presented in 2002 at Hawkings 60th birthday party/ symposium, my book, page 63. Put simply, time starts with the BB. Just as life starts with the first functional living cell. Both starts are followed by an evolutionary process which are too complex to be the result of chance. If there is a cause for each event, it is simpler to attribute them to one source than to conjure up two causes for two such pivotal creations.
dhw: A strange volte face. According to you, your God caused the BB, and so he existed before the BB. Before, now and after are one concept of time. Nobody can possibly prove anything about what happened before the BB (if it happened). I agree that one cause is simpler than two causes. The one cause may be an eternal and infinite universe of energy and matter constantly changing itself. No, I don’t believe it, and I don’t disbelieve it, just as I don’t believe or disbelieve in a single, conscious, sourceless, eternal mind. Maybe the complex evolutionary process was created (top down), or maybe it evolved (bottom up).
DAVID: All I presented has appeared here before. If bottom up, from what, and what pushed it to evolve?
Yes, we have discussed it many times. Bottom up from eternally changing combinations of materials. But I can't tell you how they might have acquired the basic consciosuness to form life, any more than you can tell me how a sourceless, universal, conscious mind can simply have been there for ever. Two first cause hypotheses that are as inexplicable as each other. Enough to make a thinker embrace agnosticism!
Human evolution; our complex speech mechanism
by David Turell , Wednesday, December 05, 2018, 20:22 (2178 days ago) @ dhw
DAVID: According to Guth and his cohorts there is no 'before' before the Big Bang, proven mathematically in a paper presented in 2002 at Hawkings 60th birthday party/ symposium, my book, page 63. Put simply, time starts with the BB. Just as life starts with the first functional living cell. Both starts are followed by an evolutionary process which are too complex to be the result of chance. If there is a cause for each event, it is simpler to attribute them to one source than to conjure up two causes for two such pivotal creations.
dhw: A strange volte face. According to you, your God caused the BB, and so he existed before the BB. Before, now and after are one concept of time. Nobody can possibly prove anything about what happened before the BB (if it happened). I agree that one cause is simpler than two causes. The one cause may be an eternal and infinite universe of energy and matter constantly changing itself. No, I don’t believe it, and I don’t disbelieve it, just as I don’t believe or disbelieve in a single, conscious, sourceless, eternal mind. Maybe the complex evolutionary process was created (top down), or maybe it evolved (bottom up).
DAVID: All I presented has appeared here before. If bottom up, from what, and what pushed it to evolve?
dhw: Yes, we have discussed it many times. Bottom up from eternally changing combinations of materials. But I can't tell you how they might have acquired the basic consciosuness to form life, any more than you can tell me how a sourceless, universal, conscious mind can simply have been there for ever. Two first cause hypotheses that are as inexplicable as each other. Enough to make a thinker embrace agnosticism!
Not if one tries to explain the complex designs in living forms.
Human evolution; our complex speech mechanism
dhw: According to you, your God caused the BB, and so he existed before the BB. Before, now and after are one concept of time. Nobody can possibly prove anything about what happened before the BB (if it happened). I agree that one cause is simpler than two causes. The one cause may be an eternal and infinite universe of energy and matter constantly changing itself. No, I don’t believe it, and I don’t disbelieve it, just as I don’t believe or disbelieve in a single, conscious, sourceless, eternal mind. Maybe the complex evolutionary process was created (top down), or maybe it evolved (bottom up).
DAVID: All I presented has appeared here before. If bottom up, from what, and what pushed it to evolve?
dhw: Yes, we have discussed it many times. Bottom up from eternally changing combinations of materials. But I can't tell you how they might have acquired the basic consciousness to form life, any more than you can tell me how a sourceless, universal, conscious mind can simply have been there for ever. Two first cause hypotheses that are as inexplicable as each other. Enough to make a thinker embrace agnosticism!
DAVID: Not if one tries to explain the complex designs in living forms.
I accept that as a good reason for your faith – but you have always acknowledged that it requires faith and not reason to accept one mystery as the answer to another.
Human evolution; our complex speech mechanism
by David Turell , Thursday, December 06, 2018, 19:33 (2177 days ago) @ dhw
dhw: According to you, your God caused the BB, and so he existed before the BB. Before, now and after are one concept of time. Nobody can possibly prove anything about what happened before the BB (if it happened). I agree that one cause is simpler than two causes. The one cause may be an eternal and infinite universe of energy and matter constantly changing itself. No, I don’t believe it, and I don’t disbelieve it, just as I don’t believe or disbelieve in a single, conscious, sourceless, eternal mind. Maybe the complex evolutionary process was created (top down), or maybe it evolved (bottom up).
DAVID: All I presented has appeared here before. If bottom up, from what, and what pushed it to evolve?
dhw: Yes, we have discussed it many times. Bottom up from eternally changing combinations of materials. But I can't tell you how they might have acquired the basic consciousness to form life, any more than you can tell me how a sourceless, universal, conscious mind can simply have been there for ever. Two first cause hypotheses that are as inexplicable as each other. Enough to make a thinker embrace agnosticism!
DAVID: Not if one tries to explain the complex designs in living forms.
dhw: I accept that as a good reason for your faith – but you have always acknowledged that it requires faith and not reason to accept one mystery as the answer to another.
Reasoning about the need for a designer is strong enough to lead to faith. In my mind there must be a designer. The complex living biology I see and understand with my medical training requires that conclusion. You and I have different backgrounds, which may explain our different positions.
Human evolution; another Australopithecus species? ignore
by David Turell , Friday, December 07, 2018, 01:44 (2176 days ago) @ David Turell
edited by David Turell, Friday, December 07, 2018, 01:55
Still under debate about it, but sure looks like it:
https://www.newscientist.com/article/2187639-exclusive-controversial-skeleton-may-be-a-...
"More than twenty years after it was first discovered, an analysis of a remarkable skeleton discovered in South Africa has finally been published – and the specimen suggests we may need to add a new species to the family tree of early human ancestors.
"The analysis also found evidence that the species was evolving to become better at striding on two legs, helping us to understand when our lineage first became bipedal.
"The specimen, nicknamed “Little Foot”, is a type of Australopithecus, the group of hominins to which the famous fossil “Lucy” belonged. Lucy’s species is called A. afarensis, but we know of several other species of these human-like primates living in Africa around 2 million years ago, including A. africanus.
***
"The Little Foot fossil came to light in the 1990s. Ronald Clarke of the University of the Witwatersrand in Johannesburg, South Africa was asked to go through a collection of bones from Sterkfontein Cave in South Africa. In 1994 he found that four foot bones, thought to belong to monkeys, actually resembled existing fossils belonging to the Australopithecus group.
"The foot bones were quite small, prompting Clarke’s now-deceased colleague Phillip Tobias to dub them “Little Foot”, in reference to the Bigfoot hominin that some believe roams North America.
"In 1997, Clarke and two colleagues found more of the skeleton encased in rock within the same cave. He began excavating it, a process that continued for over a decade. Because the fossilised bone flaked easily, Clarke chose to painstakingly remove the bones from the rock using only an air scribe – a tool that shoots out a thin jet of pressurised air.
***
"The result is a virtually complete skeleton that promises to tell us much about early human-like primates.
A flurry of initial studies, published at last, reveal that Little Foot was an elderly female, about 130 centimetres in height.
"According to a study led by Travis Pickering of the University of Wisconsin-Madison, Little Foot had an arm injury. He suspects she fell onto an outstretched hand during her youth, and that the resulting injury troubled her throughout her life.
"Robin Crompton of the University of Liverpool, UK and his colleagues have analysed how she would have walked. He says it is the first fossil of this age ever to have been discovered with its limbs fully intact.
“'This hominin had longer lower limbs than upper limbs, like ourselves,” says Crompton. This is an interesting finding, as the slightly older hominin Ardipithecus, which came before Australopithecus, had longer arms than legs – more like great apes do. “That means it was being selected for stride length in bipedalism,” says Crompton.
"Little Foot would not have been as good at carrying objects as we are. However, she would have been better at climbing trees than modern humans.
"That would have suited her home: a mix of tropical rainforest, broken woodland and grassland, through which she roamed widely.
A further paper examines the deposits in which Little Foot was encased and concludes that the fossil is 3.67 million years old, more than a million years older than previously thought. (my bold)
"Clarke has argued for over a decade that Little Foot does not belong to any of the known Australopithecus species, and should be named a new species in its own right. He favours calling it A. prometheus.
"The name was coined in 1948 by Raymond Dart, to describe a piece of skull found at Makapansgat in South Africa. Dart is a key figure in anthropology, because in 1925 he described the first Australopithecus specimen, the Taung Child. He used the fossil to argue that humans evolved in Africa. At the time most biologists thought our origins lay in Asia, and Dart was ridiculed for years until other discoveries confirmed that he was right.
"Clarke is convinced that many of the bones from Sterkfontein, including Little Foot, are not A. africanus, so he has resurrected the name A. prometheus. “There are many, many differences, not only in the skull but also in the rest of the skeleton,” he says. They include a flatter face than A. africanus, and larger teeth with a big gap between the upper canines and incisors.
"There is also Little Foot’s diet. Based on her teeth, she ate almost nothing but plants. “A. africanus was more omnivorous,” says Clarke."
Comment: The main thrust here to recognize is that this lady is Lucy's age in fossil time, but she has longer arms than legs and Lucy is longer arms. What this means is a that there were several lines of hominin development going on at different places in Africa in the same periods of time. Places of discovery, to remind us, Lucy is Northeastern Africa and Little Foot is South Africa. It suggests God liked diversity in evolving humans, just as He created diversity in the huge bush of like. I suspect the reason for the diversity in life is econiches for food, while I suspect He already knew what H' sapiens would be like when evolution got to that point..
Human evolution; another Australopithecus species?
by David Turell , Friday, December 07, 2018, 01:45 (2176 days ago) @ David Turell
Still under debate about it, but sure looks like it:
https://www.newscientist.com/article/2187639-exclusive-controversial-skeleton-may-be-a-...
More than twenty years after it was first discovered, an analysis of a remarkable skeleton discovered in South Africa has finally been published – and the specimen suggests we may need to add a new species to the family tree of early human ancestors.
"The analysis also found evidence that the species was evolving to become better at striding on two legs, helping us to understand when our lineage first became bipedal.
"The specimen, nicknamed “Little Foot”, is a type of Australopithecus, the group of hominins to which the famous fossil “Lucy” belonged. Lucy’s species is called A. afarensis, but we know of several other species of these human-like primates living in Africa around 2 million years ago, including A. africanus.
***
"The Little Foot fossil came to light in the 1990s. Ronald Clarke of the University of the Witwatersrand in Johannesburg, South Africa was asked to go through a collection of bones from Sterkfontein Cave in South Africa. In 1994 he found that four foot bones, thought to belong to monkeys, actually resembled existing fossils belonging to the Australopithecus group.
"The foot bones were quite small, prompting Clarke’s now-deceased colleague Phillip Tobias to dub them “Little Foot”, in reference to the Bigfoot hominin that some believe roams North America.
"In 1997, Clarke and two colleagues found more of the skeleton encased in rock within the same cave. He began excavating it, a process that continued for over a decade. Because the fossilised bone flaked easily, Clarke chose to painstakingly remove the bones from the rock using only an air scribe – a tool that shoots out a thin jet of pressurised air.
***
"The result is a virtually complete skeleton that promises to tell us much about early human-like primates.
A flurry of initial studies, published at last, reveal that Little Foot was an elderly female, about 130 centimetres in height.
"According to a study led by Travis Pickering of the University of Wisconsin-Madison, Little Foot had an arm injury. He suspects she fell onto an outstretched hand during her youth, and that the resulting injury troubled her throughout her life.
"Robin Crompton of the University of Liverpool, UK and his colleagues have analysed how she would have walked. He says it is the first fossil of this age ever to have been discovered with its limbs fully intact.
“'This hominin had longer lower limbs than upper limbs, like ourselves,” says Crompton. This is an interesting finding, as the slightly older hominin Ardipithecus, which came before Australopithecus, had longer arms than legs – more like great apes do. “That means it was being selected for stride length in bipedalism,” says Crompton.
"Little Foot would not have been as good at carrying objects as we are. However, she would have been better at climbing trees than modern humans.
"That would have suited her home: a mix of tropical rainforest, broken woodland and grassland, through which she roamed widely.
A further paper examines the deposits in which Little Foot was encased and concludes that the fossil is 3.67 million years old, more than a million years older than previously thought. (my bold)
"Clarke has argued for over a decade that Little Foot does not belong to any of the known Australopithecus species, and should be named a new species in its own right. He favours calling it A. prometheus.
"The name was coined in 1948 by Raymond Dart, to describe a piece of skull found at Makapansgat in South Africa. Dart is a key figure in anthropology, because in 1925 he described the first Australopithecus specimen, the Taung Child. He used the fossil to argue that humans evolved in Africa. At the time most biologists thought our origins lay in Asia, and Dart was ridiculed for years until other discoveries confirmed that he was right.
"Clarke is convinced that many of the bones from Sterkfontein, including Little Foot, are not A. africanus, so he has resurrected the name A. prometheus. “There are many, many differences, not only in the skull but also in the rest of the skeleton,” he says. They include a flatter face than A. africanus, and larger teeth with a big gap between the upper canines and incisors.
"There is also Little Foot’s diet. Based on her teeth, she ate almost nothing but plants. “A. africanus was more omnivorous,” says Clarke."
Comment: The main thrust here to recognize is that this lady is roughly Lucy's age in fossil time, but she has longer arms than legs and Lucy is longer arms. What this means is a that there were several lines of hominin development going on at different places in Africa in the same periods of time. Places of discovery, to remind us, Lucy is Northeastern Africa and Little Foot is South Africa. It suggests God liked diversity in evolving humans, just as He created diversity in the huge bush of like. I suspect the reason for the diversity in life is econiches for food, while I suspect He already knew what H' sapiens would be like when evolution got to that point..
Human evolution; another Australopithecus species?
by David Turell , Wednesday, December 12, 2018, 04:57 (2171 days ago) @ David Turell
“'This hominin had longer lower limbs than upper limbs, like ourselves,” says Crompton. This is an interesting finding, as the slightly older hominin Ardipithecus, which came before Australopithecus, had longer arms than legs – more like great apes do. “That means it was being selected for stride length in bipedalism,” says Crompton.
"Little Foot would not have been as good at carrying objects as we are. However, she would have been better at climbing trees than modern humans.
"That would have suited her home: a mix of tropical rainforest, broken woodland and grassland, through which she roamed widely.
A further paper examines the deposits in which Little Foot was encased and concludes that the fossil is 3.67 million years old, more than a million years older than previously thought. (my bold)
"Clarke has argued for over a decade that Little Foot does not belong to any of the known Australopithecus species, and should be named a new species in its own right. He favours calling it A. prometheus.
"The name was coined in 1948 by Raymond Dart, to describe a piece of skull found at Makapansgat in South Africa. Dart is a key figure in anthropology, because in 1925 he described the first Australopithecus specimen, the Taung Child. He used the fossil to argue that humans evolved in Africa. At the time most biologists thought our origins lay in Asia, and Dart was ridiculed for years until other discoveries confirmed that he was right.
"Clarke is convinced that many of the bones from Sterkfontein, including Little Foot, are not A. africanus, so he has resurrected the name A. prometheus. “There are many, many differences, not only in the skull but also in the rest of the skeleton,” he says. They include a flatter face than A. africanus, and larger teeth with a big gap between the upper canines and incisors.
"There is also Little Foot’s diet. Based on her teeth, she ate almost nothing but plants. “A. africanus was more omnivorous,” says Clarke."
Comment: The main thrust here to recognize is that this lady is roughly Lucy's age in fossil time, but she has longer arms than legs and Lucy is longer arms. What this means is a that there were several lines of hominin development going on at different places in Africa in the same periods of time. Places of discovery, to remind us, Lucy is Northeastern Africa and Little Foot is South Africa. It suggests God liked diversity in evolving humans, just as He created diversity in the huge bush of like. I suspect the reason for the diversity in life is econiches for food, while I suspect He already knew what H' sapiens would be like when evolution got to that point..
This comment is incorrect in that it reversed arm and leg length, which is clear in the article. Little foot had longer legs and is more advanced in bipedalism than Lucy who is younger in the timing of evolution.
New article really adds little::
https://www.livescience.com/64275-little-foot-hominin-excavated.html?utm_source=ls-news...
Human evolution; "Little foot's" brain
by David Turell , Tuesday, December 18, 2018, 19:09 (2165 days ago) @ David Turell
Her brain is both ape and human:
https://phys.org/news/2018-12-peering-foot-million-year-old-brain.html
"MicroCT scans of the Australopithecus fossil known as Little Foot shows that the brain of this ancient human relative was small and shows features that are similar to our own brain and others that are closer to our ancestor shared with living chimpanzees.
"While the brain features structures similar to modern humans—such as an asymmetrical structure and pattern of middle meningeal vessels—some of its critical areas such as an expanded visual cortex and reduced parietal association cortex points to a condition that is distinct from us.
***
"The endocast showed that Little Foot's brain was asymmetrical, with a distinct left occipital petalia. Brain asymmetry is essential for lateralisation of brain function. Asymmetry occurs in humans and living apes, as well as in other younger hominin endocasts. Little Foot now shows us that this brain asymmetry was present at a very early date (from 3.67 million years ago), and supports suggestions that it was probably present in the last common ancestor of hominins and other great apes.
"Other brain structures, such as an expanded visual cortex, suggests that the brain of Little Foot probably had some features that are closer to the ancestor we share with living chimpanzees.
"'In human evolution, when know that a reduced visual cortex, as we can see in our own brain, is related to a more expanded parietal cortex—which is a critical cerebral area responsible for several aspects of sensory processing and sensorimotor integration," says Beaudet. "On the contrary, Little Foot has a large visual cortex, which is more similar to chimpanzees than to humans."
"Beaudet and her colleagues compared the Little Foot endocast with endocasts of 10 other South African hominins dating between three and 1.5 million years ago. Their preliminary calculation of Little Foot's endocranial volume was found to be at the low end of the range for Australopithecus, which is in keeping with its great age and its place among other very early fossils of Australopithecus from East Africa.
"The study also has shown that the vascular system in Australopithecus was more complex than previously thought, which raises new questions on the metabolism of the brain at this time. This might be consistent with a previous hypothesis suggesting that the endocranial vascular system in Australopithecus was closer to modern humans than it was in the geologically younger Paranthropus genus. (my bold)
""This would mean that even if Little Foot's brain was different from us, the vascular system that allows for blood flow (which brings oxygen) and may control temperature in the brain—both essential aspects for evolving a large and complex brain—were possibly already present at that time," says Beaudet.
"Given its geological age of over 3 million years, Little Foot's brain suggests that younger hominins evolved greater complexity in certain brain structures over time, perhaps in response to increasing environmental pressures experienced after 2.6 million years ago with continuing reduction in closed habitats.
"'Such environmental changes could also potentially have encouraged more complex social interaction, which is driven by structures in the brain," says Beaudet. "
Comment: Little Foot is obviously a transitional form. But note my bold about the somewhat advanced vascular system. Advanced planning by God? Social relations were also dictated by hunter-gatherers groups which had to form for survival as small groups cooperation provided food and protection.Brain plasticity would have made brain changes as socialization progressed.
Human evolution; "Little foot's" brain
QUOTES: The study also has shown that the vascular system in Australopithecus was more complex than previously thought, which raises new questions on the metabolism of the brain at this time. This might be consistent with a previous hypothesis suggesting that the endocranial vascular system in Australopithecus was closer to modern humans than it was in the geologically younger Paranthropus genus. (David’s bold)
Given its geological age of over 3 million years, Little Foot's brain suggests that younger hominins evolved greater complexity in certain brain structures over time, perhaps in response to increasing environmental pressures experienced after 2.6 million years ago with continuing reduction in closed habitats. (dhw’s bold)
"'Such environmental changes could also potentially have encouraged more complex social interaction, which is driven by structures in the brain," says Beaudet. (dhw’s bold)
DAVID:Little Foot is obviously a transitional form.
Yes, she provides yet more evidence of common descent.
DAVID: But note my bold about the somewhat advanced vascular system. Advanced planning by God?
If so, then why would he have bothered to introduce the less advanced system later on?
DAVID: Social relations were also dictated by hunter-gatherers groups which had to form for survival as small groups cooperation provided food and protection. Brain plasticity would have made brain changes as socialization progressed.
Delighted to see you acknowledging that this area of evolution was dictated by the survivability which you tell us plays little or no role in evolution. But I’m interested mainly in the two sections I’ve bolded. Increasing environmental pressures demand increased brain activity if the hominin is to survive – i.e. brain change is in response to new requirements. But the second bold suggests the reverse – that it is the brain that drives new activities. This is a contradiction. I would support the first bold: that environmental change requires new activities, and it is these activities that change the brain.
Human evolution; "Little foot's" brain
by David Turell , Wednesday, December 19, 2018, 18:45 (2164 days ago) @ dhw
QUOTES: The study also has shown that the vascular system in Australopithecus was more complex than previously thought, which raises new questions on the metabolism of the brain at this time. This might be consistent with a previous hypothesis suggesting that the endocranial vascular system in Australopithecus was closer to modern humans than it was in the geologically younger Paranthropus genus. (David’s bold)
Given its geological age of over 3 million years, Little Foot's brain suggests that younger hominins evolved greater complexity in certain brain structures over time, perhaps in response to increasing environmental pressures experienced after 2.6 million years ago with continuing reduction in closed habitats. (dhw’s bold)
"'Such environmental changes could also potentially have encouraged more complex social interaction, which is driven by structures in the brain," says Beaudet. (dhw’s bold)
DAVID:Little Foot is obviously a transitional form.
dhw: Yes, she provides yet more evidence of common descent.
OK
DAVID: But note my bold about the somewhat advanced vascular system. Advanced planning by God?dhw: If so, then why would he have bothered to introduce the less advanced system later on?
We don't have Lucy's skull which would have been later . Where did you get observation? The article indicates an improvement from Paranthropus.
DAVID: Social relations were also dictated by hunter-gatherers groups which had to form for survival as small groups cooperation provided food and protection. Brain plasticity would have made brain changes as socialization progressed.dhw: Delighted to see you acknowledging that this area of evolution was dictated by the survivability which you tell us plays little or no role in evolution. But I’m interested mainly in the two sections I’ve bolded. Increasing environmental pressures demand increased brain activity if the hominin is to survive – i.e. brain change is in response to new requirements. But the second bold suggests the reverse – that it is the brain that drives new activities. This is a contradiction. I would support the first bold: that environmental change requires new activities, and it is these activities that change the brain.
No change in your position. I do not believe survivability drives evolution.
Human evolution; "Little foot's" brain
QUOTE: The study also has shown that the vascular system in Australopithecus was more complex than previously thought, which raises new questions on the metabolism of the brain at this time. This might be consistent with a previous hypothesis suggesting that the endocranial vascular system in Australopithecus was closer to modern humans than it was in the geologically younger Paranthropus genus. (David’s bold)
DAVID: But note my bold about the somewhat advanced vascular system. Advanced planning by God?
dhw: If so, then why would he have bothered to introduce the less advanced system later on?
DAVID: We don't have Lucy's skull which would have been later . Where did you get observation? The article indicates an improvement from Paranthropus.
The section you bolded indicates that the system of the older hominin (Australopithecus) was closer to ours than that of the younger hominin (Paranthropus).
Human evolution; "Little foot's" brain
by David Turell , Thursday, December 20, 2018, 21:47 (2163 days ago) @ dhw
QUOTE: The study also has shown that the vascular system in Australopithecus was more complex than previously thought, which raises new questions on the metabolism of the brain at this time. This might be consistent with a previous hypothesis suggesting that the endocranial vascular system in Australopithecus was closer to modern humans than it was in the geologically younger Paranthropus genus. (David’s bold)
DAVID: But note my bold about the somewhat advanced vascular system. Advanced planning by God?
dhw: If so, then why would he have bothered to introduce the less advanced system later on?
DAVID: We don't have Lucy's skull which would have been later . Where did you get observation? The article indicates an improvement from Paranthropus.
dhw: The section you bolded indicates that the system of the older hominin (Australopithecus) was closer to ours than that of the younger hominin (Paranthropus).
You are correct but it appears others had a less advanced vascular system but was several million years younger. Note this from the article:
Beaudet and her colleagues compared the Little Foot endocast with endocasts of 10 other South African hominins dating between three and 1.5 million years ago. Their preliminary calculation of Little Foot's endocranial volume was found to be at the low end of the range for Australopithecus, which is in keeping with its great age and its place among other very early fossils of Australopithecus from East Africa.
Yet its vascular system is more advanced. ?Pre-planning by God?
Human evolution; "Little foot's" brain
QUOTE: The study also has shown that the vascular system in Australopithecus was more complex than previously thought, which raises new questions on the metabolism of the brain at this time. This might be consistent with a previous hypothesis suggesting that the endocranial vascular system in Australopithecus was closer to modern humans than it was in the geologically younger Paranthropus genus. (David’s bold)
DAVID: But note my bold about the somewhat advanced vascular system. Advanced planning by God?
dhw: If so, then why would he have bothered to introduce the less advanced system later on?
DAVID: We don't have Lucy's skull which would have been later . Where did you get observation? The article indicates an improvement from Paranthropus.
dhw: The section you bolded indicates that the system of the older hominin (Australopithecus) was closer to ours than that of the younger hominin (Paranthropus).
DAVID: You are correct but it appears others had a less advanced vascular system but was several million years younger. Note this from the article:
"Beaudet and her colleagues compared the Little Foot endocast with endocasts of 10 other South African hominins dating between three and 1.5 million years ago. Their preliminary calculation of Little Foot's endocranial volume was found to be at the low end of the range for Australopithecus, which is in keeping with its great age and its place among other very early fossils of Australopithecus from East Africa."
DAVID: Yet its vascular system is more advanced. Pre-planning by God?
Here are two more quotes: "This would mean that even if Little Foot's brain was different from us, the vascular system that allows for blood flow (which brings oxygen) and may control temperature in the brain—both essential aspects for evolving a large and complex brain—were possibly already present at that time," says Beaudet.
"Given its geological age of over 3 million years, Little Foot's brain suggests that younger hominins evolved greater complexity in certain brain structures over time, perhaps in response to increasing environmental pressures experienced after 2.6 million years ago with continuing reduction in closed habitats.”
If the more complex vascular system is essential for developing a more complex brain, I don’t understand why the earlier hominin with the more complex vascular system had a less complex brain than the later hominin with the less complex vascular system. And as discussed under God’s purposes and methods, I don’t understand why a God who 1) is always in full control, and 2) has the one and only purpose of creating the brain of H. sapiens, would 3) design all these different combinations. Nor do you, so maybe one or more of your three assumptions is wrong.
Human evolution; "Little foot's" brain
by David Turell , Friday, December 21, 2018, 16:22 (2162 days ago) @ dhw
DAVID: You are correct but it appears others had a less advanced vascular system but was several million years younger. Note this from the article:
"Beaudet and her colleagues compared the Little Foot endocast with endocasts of 10 other South African hominins dating between three and 1.5 million years ago. Their preliminary calculation of Little Foot's endocranial volume was found to be at the low end of the range for Australopithecus, which is in keeping with its great age and its place among other very early fossils of Australopithecus from East Africa."DAVID: Yet its vascular system is more advanced. Pre-planning by God?
dhw: Here are two more quotes: "This would mean that even if Little Foot's brain was different from us, the vascular system that allows for blood flow (which brings oxygen) and may control temperature in the brain—both essential aspects for evolving a large and complex brain—were possibly already present at that time," says Beaudet.
"Given its geological age of over 3 million years, Little Foot's brain suggests that younger hominins evolved greater complexity in certain brain structures over time, perhaps in response to increasing environmental pressures experienced after 2.6 million years ago with continuing reduction in closed habitats.”
If the more complex vascular system is essential for developing a more complex brain, I don’t understand why the earlier hominin with the more complex vascular system had a less complex brain than the later hominin with the less complex vascular system. And as discussed under God’s purposes and methods, I don’t understand why a God who 1) is always in full control, and 2) has the one and only purpose of creating the brain of H. sapiens, would 3) design all these different combinations. Nor do you, so maybe one or more of your three assumptions is wrong.
We can't get around the point Little Foot had a somewhat advanced brain circulatory system. Progress toward H. sapiens apparently went at different speeds in different areas of Africa. I can't explain it clearly to you without assuming God may have been experimenting with different approaches to evolution of humans based on differing environments, differing circulatory arrangements. There is no reason not to entertain God as being somewhat of a tinkerer. No loss of full control, but as an experimenter working things out. Remember I don't view God as religions do, absolutely omniscient. Setting up an advanced circulation before enlarging the brain makes sense since evolution builds stepwise.
Human evolution; "Little foot's" brain
I have shifted this discussion to "Divine purposes and methods".
Human evolution; "Little foot's" balance mechanism
by David Turell , Tuesday, January 15, 2019, 18:43 (2137 days ago) @ dhw
Interesting new finding about 'little foot':
https://www.livescience.com/64464-little-foot-moved-like-chimps.html?utm_source=lsa-new...
"An ancient human relative known as "Little Foot" likely walked more like a chimpanzee than like a modern human.
"Little Foot is an exceptionally well-preserved female Australopithecus — a genus in the human family tree — dating to 3.67 million years ago. Her near-complete skeleton, discovered in a cave in South Africa in 1994, was finally excavated in December after a 20-year effort (which the scientists described as a "miracle"), and close analysis of her skull enabled scientists to create 3D models of the tiny structures in her inner ear.
"This "bony labyrinth" holds important clues about balance and movement, researchers reported in a new study. In shape, Little Foot's inner-ear structure is "substantially different" from early Homo species, suggesting that she moved differently — perhaps more like our closest primate relatives, chimpanzees.
***
" For the study, the researchers scanned the interior of Little Foot's skull and used the data to construct 3D models of her inner ear. They then compared the models with the inner ears of 17 early hominin specimens, 10 extant humans and 10 chimpanzees.
"The scientists discovered that Little Foot's ear canals differed greatly from those in human ears, and they were also very different from another hominin group known as Paranthropus, which lived at the same time as early humans. In fact, Little Foot's canals were distinctly "ape-like," resembling those of chimpanzees. This suggests that the way Australopithecus moved likely had something in common with chimps, according to the study.
"Our analysis of the inner ear might be compatible with the hypothesis that Little Foot and the Australopithecus specimens in general were walking on two legs on the ground but also spent some times in the trees," Beaudet said.
"The shape of Little Foot's cochlea — a hearing organ deep inside the ear that senses vibrations — also differed from that in Homo species, implying that Australopithecus interacted with their environment differently than their human cousins, the researchers reported."
Comment: For me this study shows the vast number of ways humans differ from apes, and why design is required
Human evolution; "Little foot's" balance mechanism
"The shape of Little Foot's cochlea — a hearing organ deep inside the ear that senses vibrations — also differed from that in Homo species, implying that Australopithecus interacted with their environment differently than their human cousins, the researchers reported."
DAVID’s comment: For me this study shows the vast number of ways humans differ from apes, and why design is required.
It is perfectly reasonable for you to make such comments, but I think it is also perfectly reasonable for me to respond. There is no doubt that we differ from apes in a vast number of ways, just as we resemble them in a vast number of ways. Every complexity suggests design, but do you believe your God deliberately designed Little Foot’s cochlea and then separately designed your own? And if so, why do you think your God deliberately designed a different cochlea for Little Foot when all he really wanted to do from the very beginning was design your cochlea?
Human evolution; "Little foot's" balance mechanism
by David Turell , Wednesday, January 16, 2019, 13:46 (2136 days ago) @ dhw
"The shape of Little Foot's cochlea — a hearing organ deep inside the ear that senses vibrations — also differed from that in Homo species, implying that Australopithecus interacted with their environment differently than their human cousins, the researchers reported."
DAVID’s comment: For me this study shows the vast number of ways humans differ from apes, and why design is required.
dhw: It is perfectly reasonable for you to make such comments, but I think it is also perfectly reasonable for me to respond. There is no doubt that we differ from apes in a vast number of ways, just as we resemble them in a vast number of ways. Every complexity suggests design, but do you believe your God deliberately designed Little Foot’s cochlea and then separately designed your own? And if so, why do you think your God deliberately designed a different cochlea for Little Foot when all he really wanted to do from the very beginning was design your cochlea?
Because God used an evolutionary method requiring little steps and big jumps/gaps as history of evolution teaches us.
Human evolution; "Little foot's" balance mechanism
DAVID’s comment: For me this study shows the vast number of ways humans differ from apes, and why design is required.
dhw: It is perfectly reasonable for you to make such comments, but I think it is also perfectly reasonable for me to respond. There is no doubt that we differ from apes in a vast number of ways, just as we resemble them in a vast number of ways. Every complexity suggests design, but do you believe your God deliberately designed Little Foot’s cochlea and then separately designed your own? And if so, why do you think your God deliberately designed a different cochlea for Little Foot when all he really wanted to do from the very beginning was design your cochlea?
DAVID: Because God used an evolutionary method requiring little steps and big jumps/gaps as history of evolution teaches us.
I’m glad to hear that you incorporate little steps in your theory. Unfortunately, what we now have is that your God deliberately designed Little Foot’s cochlea, and then separately designed your cochlea, although he only wanted to design your cochlea and could have done it if he had wanted to since he is in full control. The reason why he used this method is that this is the method he used. Furthermore, what you call an “evolutionary method” is in fact a method of separate creation. I’m sure you will understand why I don’t regard this explanation as very enlightening!
Human evolution; "Little foot's" balance mechanism
by David Turell , Thursday, January 17, 2019, 19:59 (2135 days ago) @ dhw
DAVID’s comment: For me this study shows the vast number of ways humans differ from apes, and why design is required.
dhw: It is perfectly reasonable for you to make such comments, but I think it is also perfectly reasonable for me to respond. There is no doubt that we differ from apes in a vast number of ways, just as we resemble them in a vast number of ways. Every complexity suggests design, but do you believe your God deliberately designed Little Foot’s cochlea and then separately designed your own? And if so, why do you think your God deliberately designed a different cochlea for Little Foot when all he really wanted to do from the very beginning was design your cochlea?
DAVID: Because God used an evolutionary method requiring little steps and big jumps/gaps as history of evolution teaches us.
dhw: I’m glad to hear that you incorporate little steps in your theory. Unfortunately, what we now have is that your God deliberately designed Little Foot’s cochlea, and then separately designed your cochlea, although he only wanted to design your cochlea and could have done it if he had wanted to since he is in full control. The reason why he used this method is that this is the method he used. Furthermore, what you call an “evolutionary method” is in fact a method of separate creation. I’m sure you will understand why I don’t regard this explanation as very enlightening!
I'm concerned with analyzing God's works and methods. The little steps are adaptations within species and the big steps are speciation. Little Foot is a definite new species compared to previous forms and the cochlea is one of changes in the new species. In evolution we don't find God leaping from stage one whales to stage eight whales all at once, therefore it is stepwise as Darwin imagined, but not designed by a drive from survival, but designed as surviving by design in advance of the new step.
Human evolution; "Little foot's" balance mechanism
DAVID’s comment: For me this study shows the vast number of ways humans differ from apes, and why design is required.
dhw: It is perfectly reasonable for you to make such comments, but I think it is also perfectly reasonable for me to respond. There is no doubt that we differ from apes in a vast number of ways, just as we resemble them in a vast number of ways. Every complexity suggests design, but do you believe your God deliberately designed Little Foot’s cochlea and then separately designed your own? And if so, why do you think your God deliberately designed a different cochlea for Little Foot when all he really wanted to do from the very beginning was design your cochlea?
DAVID: Because God used an evolutionary method requiring little steps and big jumps/gaps as history of evolution teaches us.
dhw: I’m glad to hear that you incorporate little steps in your theory. Unfortunately, what we now have is that your God deliberately designed Little Foot’s cochlea, and then separately designed your cochlea, although he only wanted to design your cochlea and could have done it if he had wanted to since he is in full control. The reason why he used this method is that this is the method he used. Furthermore, what you call an “evolutionary method” is in fact a method of separate creation. I’m sure you will understand why I don’t regard this explanation as very enlightening!
DAVID: I'm concerned with analyzing God's works and methods. The little steps are adaptations within species and the big steps are speciation. Little Foot is a definite new species compared to previous forms and the cochlea is one of changes in the new species.
And so you have your God separately designing Little Foot’s cochlea, and then separately designing your cochlea, although he only wanted to design your cochlea and could have done so if he’d wanted to because he is always in full control. The reason why he separately designed the two cochleas is that his method was to separately design two cochleas.
DAVID: In evolution we don't find God leaping from stage one whales to stage eight whales all at once, therefore it is stepwise as Darwin imagined, but not designed by a drive from survival, but designed as surviving by design in advance of the new step.
Transferred from my earlier post under “Big brain evolution”, so do please re-read:
dhw: I don’t know how you can possibly stick to your dogma that survival “never pushes evolution”, when even your own unproven hypothesis claims that your God deliberately designed one innovation after another to enable organisms to survive under new conditions, and their purpose was to enable life forms to survive until he could produce the only life form he actually wanted to produce, which was you and me. The difference between us here is that you have the innovations/adaptations being designed (by your God) in anticipation of their being needed for survival under new conditions, whereas I have them being designed (by intelligent cell communities) in response to their being needed for survival under new conditions. In both cases, survival is the prime reason for each innovation.
DAVID: And that response to natural demands for survival is pure Darwin.
Firstly, why do you think your God specially changed pre-whale legs into fins and then made them go into the water if the fins were not designed to improve their chances of survival in the water? Secondly, you seem to think that the name Darwin automatically negates any argument. What do you find so unthinkable in the proposal that organisms change in accordance with the requirements of their surroundings, and that these changes are made because they might improve their chances of survival?
Human evolution; "Little foot's" balance mechanism
by David Turell , Friday, January 18, 2019, 22:18 (2134 days ago) @ dhw
DAVID: I'm concerned with analyzing God's works and methods. The little steps are adaptations within species and the big steps are speciation. Little Foot is a definite new species compared to previous forms and the cochlea is one of changes in the new species.
dhw: And so you have your God separately designing Little Foot’s cochlea, and then separately designing your cochlea, although he only wanted to design your cochlea and could have done so if he’d wanted to because he is always in full control. The reason why he separately designed the two cochleas is that his method was to separately design two cochleas.
His method I have constantly stated is to gradually create new species by evolving the parts of previous species. Make fun of it if you wish, but it is perfectly understandable.
DAVID: In evolution we don't find God leaping from stage one whales to stage eight whales all at once, therefore it is stepwise as Darwin imagined, but not designed by a drive from survival, but designed as surviving by design in advance of the new step.Transferred from my earlier post under “Big brain evolution”, so do please re-read:
dhw: I don’t know how you can possibly stick to your dogma that survival “never pushes evolution”, when even your own unproven hypothesis claims that your God deliberately designed one innovation after another to enable organisms to survive under new conditions, and their purpose was to enable life forms to survive until he could produce the only life form he actually wanted to produce, which was you and me. The difference between us here is that you have the innovations/adaptations being designed (by your God) in anticipation of their being needed for survival under new conditions, whereas I have them being designed (by intelligent cell communities) in response to their being needed for survival under new conditions. In both cases, survival is the prime reason for each innovation.
DAVID: And that response to natural demands for survival is pure Darwin.
dhw: Firstly, why do you think your God specially changed pre-whale legs into fins and then made them go into the water if the fins were not designed to improve their chances of survival in the water? Secondly, you seem to think that the name Darwin automatically negates any argument. What do you find so unthinkable in the proposal that organisms change in accordance with the requirements of their surroundings, and that these changes are made because they might improve their chances of survival?
He evolves these parts in advance to assure survival. The driving force is design and survival has to be a necessary byproduct so each stage of evolution can continue. Obvious.
Human evolution; "Little foot's" balance mechanism
DAVID: I'm concerned with analyzing God's works and methods. The little steps are adaptations within species and the big steps are speciation. Little Foot is a definite new species compared to previous forms and the cochlea is one of changes in the new species.
dhw: And so you have your God separately designing Little Foot’s cochlea, and then separately designing your cochlea, although he only wanted to design your cochlea and could have done so if he’d wanted to because he is always in full control. The reason why he separately designed the two cochleas is that his method was to separately design two cochleas.
DAVID: His method I have constantly stated is to gradually create new species by evolving the parts of previous species. Make fun of it if you wish, but it is perfectly understandable.
I am not making fun of his method, but of your interpretation of his method. You keep sneering at Darwin’s concept of gradual speciation, but now suddenly species are created gradually. I don’t know what you mean by “evolving” the parts, since you have told us that Little Foot is a new species, God specially designed its cochlea, and he creates every species de novo (the opposite of gradually). There is simply no consistency here or in your interpretation of your God’s purpose (to create H. sapiens), your belief that he is in full control, and that his method of creating the one thing he wants to create is to create lots of different things, including Little Foot and its cochlea, and eight stages of whale – see below.
DAVID: And that response to natural demands for survival is pure Darwin.
dhw: Firstly, why do you think your God specially changed pre-whale legs into fins and then made them go into the water if the fins were not designed to improve their chances of survival in the water? Secondly, you seem to think that the name Darwin automatically negates any argument. What do you find so unthinkable in the proposal that organisms change in accordance with the requirements of their surroundings, and that these changes are made because they might improve their chances of survival?
DAVID: He evolves these parts in advance to assure survival. The driving force is design and survival has to be a necessary byproduct so each stage of evolution can continue. Obvious.
Design is not a driving force! The driving force is the purpose of the design! And if something is designed for the purpose of ensuring survival – whether the designing anticipates a threat to survival or takes place in response to the threat – it is obvious that survival is the motive for the design. It is therefore absurd to argue that the motive for the design is not a driving force. (In both scenarios, you and I agree that the change has been designed, i.e. does not occur by chance).
Under “Lichens”:
QUOTE: The very notion of different organisms living so closely with—or within—each other was unheard of. That they should coexist to their mutual benefit was more ludicrous still. This was a mere decade after Charles Darwin had published his masterpiece, On the Origin of Species, and many biologists were gripped by the idea of nature as a gladiatorial arena, shaped by conflict.[/b] (David’s bold)
DAVID: The major point of this article is that Darwin championed the idea of evolution through conflict, struggle, and the ability to survive. The point of the article is that much of life shows cooperation and that conflict may not be that important.
How often do you have to be reminded that Lynn Margulis – following on from other authors who had posited symbiosis as a a vital part of the evolutionary process – specifically repudiated Darwin’s idea of conflict as the major driving force. Here is a quote: “The view of evolution as a chronic bloody competition among individuals and species, a popular distortion of Darwin's notion of "survival of the fittest," dissolves before a new view of continual cooperation, strong interaction, and mutual dependence among life forms. Life did not take over the globe by combat, but by networking. Life forms multiplied and complexified by co-opting others, not just by killing them.”
We have long since agreed on this. But why do you bracket it with the ability to survive? Why do you think organisms cooperate if it’s not in order to improve their chances of survival?
DAVID: Evolution can certainly mean each step is designed for survival as obviously must happen or there would be no evolution. Viewed this way, since there is no proof survival is the driving force…
If something is designed for survival, to make sure life continues, how can you say the motive for each design is not the driving force?
DAVID….it must be taken as a weak argument. And puts natural selection as a concept in a tenuous position. It can only exert its influence on what is presented by evolving forms. Like survival, it cannot be seen as driving evolution.
We have long since agreed that natural selection does not create anything and is not a driving force. Why do you keep roasting these old chestnuts?
Human evolution; "Little foot's" balance mechanism
by David Turell , Saturday, January 19, 2019, 19:33 (2133 days ago) @ dhw
DAVID: He evolves these parts in advance to assure survival. The driving force is design and survival has to be a necessary byproduct so each stage of evolution can continue. Obvious.
dhw: Design is not a driving force! The driving force is the purpose of the design!
Exactly. Design implies a designer with a purpose
dhw: And if something is designed for the purpose of ensuring survival – whether the designing anticipates a threat to survival or takes place in response to the threat – it is obvious that survival is the motive for the design.
If the purpose is a goal through evolution to create a specific life form, survival is necessary but not a primary force. The purpose is! Design for survival is a byproduct of the purposeful design of teh designer.
Under “Lichens”:QUOTE: The very notion of different organisms living so closely with—or within—each other was unheard of. That they should coexist to their mutual benefit was more ludicrous still. This was a mere decade after Charles Darwin had published his masterpiece, On the Origin of Species, and many biologists were gripped by the idea of nature as a gladiatorial arena, shaped by conflict.[/b] (David’s bold)
DAVID: The major point of this article is that Darwin championed the idea of evolution through conflict, struggle, and the ability to survive. The point of the article is that much of life shows cooperation and that conflict may not be that important.
dhw: How often do you have to be reminded that Lynn Margulis – following on from other authors who had posited symbiosis as a a vital part of the evolutionary process – specifically repudiated Darwin’s idea of conflict as the major driving force. Here is a quote: “The view of evolution as a chronic bloody competition among individuals and species, a popular distortion of Darwin's notion of "survival of the fittest," dissolves before a new view of continual cooperation, strong interaction, and mutual dependence among life forms. Life did not take over the globe by combat, but by networking. Life forms multiplied and complexified by co-opting others, not just by killing them.”
We have long since agreed on this. But why do you bracket it with the ability to survive? Why do you think organisms cooperate if it’s not in order to improve their chances of survival?
DAVID: Evolution can certainly mean each step is designed for survival as obviously must happen or there would be no evolution. Viewed this way, since there is no proof survival is the driving force…
dhw: If something is designed for survival, to make sure life continues, how can you say the motive for each design is not the driving force?
See above.
DAVID….it must be taken as a weak argument. And puts natural selection as a concept in a tenuous position. It can only exert its influence on what is presented by evolving forms. Like survival, it cannot be seen as driving evolution.dhw: We have long since agreed that natural selection does not create anything and is not a driving force. Why do you keep roasting these old chestnuts?
I simply presented the essay as view with which I agree, and it shows how Darwin's concepts poisoned future reasoning. I think your reasoning uses the concept of struggle for survival far beyond its usefulness.
Human evolution; "Little foot's" balance mechanism
DAVID: He evolves these parts in advance to assure survival. The driving force is design and survival has to be a necessary byproduct so each stage of evolution can continue. Obvious.
dhw: Design is not a driving force! The driving force is the purpose of the design!
DAVID: Exactly. Design implies a designer with a purpose.
“Exactly” what? The driving force is not design but the motive for the design.
dhw: And if something is designed for the purpose of ensuring survival – whether the designing anticipates a threat to survival or takes place in response to the threat – it is obvious that survival is the motive for the design.
DAVID: If the purpose is a goal through evolution to create a specific life form, survival is necessary but not a primary force. The purpose is! Design for survival is a byproduct of the purposeful design of the designer.
So your designer did not design the whale’s fin to help the whale to survive in water; he designed it so that he would be able to design the human ear, pelvis, brain and bipedalism.
Under “Lichens”:
DAVID: The major point of this article is that Darwin championed the idea of evolution through conflict, struggle, and the ability to survive. The point of the article is that much of life shows cooperation and that conflict may not be that important.
dhw: How often do you have to be reminded that Lynn Margulis – following on from other authors who had posited symbiosis as a a vital part of the evolutionary process – specifically repudiated Darwin’s idea of conflict as the major driving force. […]
We have long since agreed on this. But why do you bracket it with the ability to survive? Why do you think organisms cooperate if it’s not in order to improve their chances of survival?
Not answered.
dhw: If something is designed for survival, to make sure life continues, how can you say the motive for each design is not the driving force?
DAVID: ...it must be taken as a weak argument. And puts natural selection as a concept in a tenuous position. It can only exert its influence on what is presented by evolving forms. Like survival, it cannot be seen as driving evolution.
dhw: We have long since agreed that natural selection does not create anything and is not a driving force. Why do you keep roasting these old chestnuts?
DAVID: I simply presented the essay as view with which I agree, and it shows how Darwin's concepts poisoned future reasoning. I think your reasoning uses the concept of struggle for survival far beyond its usefulness.
Your hatred of Darwin simply blinds you to obvious truths. Please answer the question above: why do you think organisms cooperate if it’s not in order to improve their chances of survival?
Human evolution; "Little foot's" balance mechanism
by David Turell , Sunday, January 20, 2019, 18:34 (2132 days ago) @ dhw
DAVID: If the purpose is a goal through evolution to create a specific life form, survival is necessary but not a primary force. The purpose is! Design for survival is a byproduct of the purposeful design of the designer.
dhw: So your designer did not design the whale’s fin to help the whale to survive in water; he designed it so that he would be able to design the human ear, pelvis, brain and bipedalism.
Glib response. Just accept the obvious. From simple to complex in evolution can be created in stepwise fashion .
Under “Lichens”:
DAVID: The major point of this article is that Darwin championed the idea of evolution through conflict, struggle, and the ability to survive. The point of the article is that much of life shows cooperation and that conflict may not be that important.
dhw: How often do you have to be reminded that Lynn Margulis – following on from other authors who had posited symbiosis as a a vital part of the evolutionary process – specifically repudiated Darwin’s idea of conflict as the major driving force. […]
We have long since agreed on this. But why do you bracket it with the ability to survive? Why do you think organisms cooperate if it’s not in order to improve their chances of survival?Not answered.
I accept Margulis. I always have. Of course there is cooperation. Note my presentation of lichens. Lichens have a purpose in that they break down lava rock on the way to soil for plants. Everything in evolution fills God purposes to eventually create humans. And He must design for survival if his method is to continue .
dhw: If something is designed for survival, to make sure life continues, how can you say the motive for each design is not the driving force?DAVID: ...it must be taken as a weak argument. And puts natural selection as a concept in a tenuous position. It can only exert its influence on what is presented by evolving forms. Like survival, it cannot be seen as driving evolution.
dhw: We have long since agreed that natural selection does not create anything and is not a driving force. Why do you keep roasting these old chestnuts?
DAVID: I simply presented the essay as view with which I agree, and it shows how Darwin's concepts poisoned future reasoning. I think your reasoning uses the concept of struggle for survival far beyond its usefulness.
dhw: Your hatred of Darwin simply blinds you to obvious truths. Please answer the question above: why do you think organisms cooperate if it’s not in order to improve their chances of survival?
I don't hate Darwin. He opened up an area for research and discussion by making us all recognize we got here by evolution. His antiquated arguments were reasonable enough at his time in life, but they need to be fully abandoned as we learn what he theorized as causing evolution is totally wrong. I only hate what his followers have created in a religion of Darwinism to protect his out-of-date ideas.
Human evolution; "Little foot's" balance mechanism
DAVID: If the purpose is a goal through evolution to create a specific life form, survival is necessary but not a primary force. The purpose is! Design for survival is a byproduct of the purposeful design of the designer.
dhw: So your designer did not design the whale’s fin to help the whale to survive in water; he designed it so that he would be able to design the human ear, pelvis, brain and bipedalism.
DAVID:Glib response. Just accept the obvious. From simple to complex in evolution can be created in stepwise fashion.
Of course it can! How does that support your contention that your God did not design the whale’s fin in order to help the whale survive in water, but in order to enable him to design the human ear, pelvis etc.? This raises the next question, which you keep refusing to answer:
dhw: Why do you think organisms cooperate if it’s not in order to improve their chances of survival?
DAVID: I accept Margulis. I always have. Of course there is cooperation. Note my presentation of lichens. Lichens have a purpose in that they break down lava rock on the way to soil for plants. Everything in evolution fills God purposes to eventually create humans. And He must design for survival if his method is to continue.
So the purpose of organisms cooperating or of your God specially designing dinosaurs to eat one another, and turning pre-whale legs into fins, and teaching monarch butterflies the route to safety, and camouflaging cuttlefish, and specially designing 50,000 different spider webs had nothing to do with helping those organisms to survive, but it was to help those organisms to survive! Because if those evolutionary developments hadn’t been specially designed to help those organisms to survive, your always-in-control God couldn’t have stuck to his self-imposed timetable of specially designing H. sapiens after 3.5+ billion years.
DAVID: I simply presented the essay as view with which I agree, and it shows how Darwin's concepts poisoned future reasoning. I think your reasoning uses the concept of struggle for survival far beyond its usefulness.
dhw: Your hatred of Darwin simply blinds you to obvious truths. Please answer the question above: why do you think organisms cooperate if it’s not in order to improve their chances of survival?
DAVID: I don't hate Darwin. He opened up an area for research and discussion by making us all recognize we got here by evolution. His antiquated arguments were reasonable enough at his time in life, but they need to be fully abandoned as we learn what he theorized as causing evolution is totally wrong.
Abandoning ideas such as random mutations as the cause of innovation, and nature never jumps, is in my view very reasonable. That is not the same as “fully” abandoning his ideas. I’m actually surprised to hear that you still recognize that we got here by evolution, when in a recent post you believed that your God “creates species de novo”, but perhaps this is no more surprising than your insistence that survival is not a driving force for evolution even though you think your God specially designed innovations in order to help the organisms survive (as above), or your reluctance to answer questions such as: why do you think organisms cooperate if it’s not in order to improve their chances of survival?
DAVID: I only hate what his followers have created in a religion of Darwinism to protect his out-of-date ideas.
I agree that some of Darwin’s ideas are out of date (as above), but some are not. I also hate it when both theists and atheists distort Darwin’s ideas and pretend that evolution is incompatible with religious belief when he explicitly pointed out that it wasn’t.
Human evolution; "Little foot's" balance mechanism
by David Turell , Monday, January 21, 2019, 15:33 (2131 days ago) @ dhw
DAVID:Glib response. Just accept the obvious. From simple to complex in evolution can be created in stepwise fashion.
dhw: Of course it can! How does that support your contention that your God did not design the whale’s fin in order to help the whale survive in water, but in order to enable him to design the human ear, pelvis etc.? This raises the next question, which you keep refusing to answer:
dhw: Why do you think organisms cooperate if it’s not in order to improve their chances of survival?
Survival is required for evolution to continue. Survival is designed into the process by God.
DAVID: I accept Margulis. I always have. Of course there is cooperation. Note my presentation of lichens. Lichens have a purpose in that they break down lava rock on the way to soil for plants. Everything in evolution fills God purposes to eventually create humans. And He must design for survival if his method is to continue.dhw: So the purpose of organisms cooperating or of your God specially designing dinosaurs to eat one another, and turning pre-whale legs into fins, and teaching monarch butterflies the route to safety, and camouflaging cuttlefish, and specially designing 50,000 different spider webs had nothing to do with helping those organisms to survive, but it was to help those organisms to survive! Because if those evolutionary developments hadn’t been specially designed to help those organisms to survive, your always-in-control God couldn’t have stuck to his self-imposed timetable of specially designing H. sapiens after 3.5+ billion years.
Welcome to the clear history of evolution. Survival is obviously required for evolution to continue. "Struggle for survival" does not drive evolution.
DAVID: I don't hate Darwin. He opened up an area for research and discussion by making us all recognize we got here by evolution. His antiquated arguments were reasonable enough at his time in life, but they need to be fully abandoned as we learn what he theorized as causing evolution is totally wrong.Abandoning ideas such as random mutations as the cause of innovation, and nature never jumps, is in my view very reasonable. That is not the same as “fully” abandoning his ideas. I’m actually surprised to hear that you still recognize that we got here by evolution, when in a recent post you believed that your God “creates species de novo”, but perhaps this is no more surprising than your insistence that survival is not a driving force for evolution even though you think your God specially designed innovations in order to help the organisms survive (as above), or your reluctance to answer questions such as: why do you think organisms cooperate if it’s not in order to improve their chances of survival?
Cooperation helps survival, but you keep insisting survival drives evolution and that is a concept that is unproven.
DAVID: I only hate what his followers have created in a religion of Darwinism to protect his out-of-date ideas.dhw: I agree that some of Darwin’s ideas are out of date (as above), but some are not. I also hate it when both theists and atheists distort Darwin’s ideas and pretend that evolution is incompatible with religious belief when he explicitly pointed out that it wasn’t.
Which of Darwin's ideas do you cling to? Both of us accept that we evolved as he championed. Anything more?
Human evolution; "Little foot's" balance mechanism
dhw: Why do you think organisms cooperate if it’s not in order to improve their chances of survival?
DAVID: Cooperation helps survival, but you keep insisting survival drives evolution and that is a concept that is unproven.
And
DAVID: Survival is required for evolution to continue. Survival is designed into the process by God.
I would have thought that for most people the role of survival as a driving force is blindingly obvious, and even you keep agreeing that the purpose of cooperation between organisms, the development of fins, camouflage and migration– whether designed by your God or designed by the cell communities themselves – is to ensure survival! If you wish to add to this your personal and inexplicable belief that your God’s reason for wanting the whale to survive in water, the cuttlefish to survive predation, and the monarch butterfly to survive the winter, was that if they hadn‘t, he couldn’t have waited 3.5+ billion years in order to specially design you and me, that’s up to you. But it does not alter the fact that the purpose of the fin, the camouflage and the migration was to improve chances of survival, and for most of us the purpose of something is the driving force behind its coming into being.
The next section of your post deals with the same conflation of the blindingly obvious purpose of survival, which you keep acknowledging, with the overall purpose you impose on your God of filling in 3.5+ billion years of life before he specially designs the only thing he actually wants to design.
DAVID: I only hate what his [Darwin’s] followers have created in a religion of Darwinism to protect his out-of-date ideas.
dhw: I agree that some of Darwin’s ideas are out of date (as above), but some are not. I also hate it when both theists and atheists distort Darwin’s ideas and pretend that evolution is incompatible with religious belief when he explicitly pointed out that it wasn’t.
DAVID: Which of Darwin's ideas do you cling to? Both of us accept that we evolved as he championed. Anything more?
Sometimes you say you accept evolution, but sometimes you insist that every innovation was specially designed and you subscribe directly to Creationism: “I think God creates species de novo in an evolving order.” I don’t know what you meant by an evolving order, but de novo could hardly be clearer. I accept common descent, the influence of the environment on speciation, survival as the driving force (which entails cooperation as well as competition), and natural selection as a neat term to explain the survival of organs and organisms (but NOT to explain speciation). I am only against random mutations as the cause of innovations, and Darwin’s insistence that “natura non facit saltus”.
Human evolution; "Little foot's" balance mechanism
by David Turell , Tuesday, January 22, 2019, 16:55 (2130 days ago) @ dhw
dhw: Why do you think organisms cooperate if it’s not in order to improve their chances of survival?
DAVID: Cooperation helps survival, but you keep insisting survival drives evolution and that is a concept that is unproven.
And
DAVID: Survival is required for evolution to continue. Survival is designed into the process by God.
dhw: I would have thought that for most people the role of survival as a driving force is blindingly obvious, and even you keep agreeing that the purpose of cooperation between organisms, the development of fins, camouflage and migration– whether designed by your God or designed by the cell communities themselves – is to ensure survival! If you wish to add to this your personal and inexplicable belief that your God’s reason for wanting the whale to survive in water, the cuttlefish to survive predation, and the monarch butterfly to survive the winter, was that if they hadn‘t, he couldn’t have waited 3.5+ billion years in order to specially design you and me, that’s up to you. But it does not alter the fact that the purpose of the fin, the camouflage and the migration was to improve chances of survival, and for most of us the purpose of something is the driving force behind its coming into being.
Our difference is that I view God as driving evolution step by step which makes survival a non-driving force
dhw: I agree that some of Darwin’s ideas are out of date (as above), but some are not. I also hate it when both theists and atheists distort Darwin’s ideas and pretend that evolution is incompatible with religious belief when he explicitly pointed out that it wasn’t.
DAVID: Which of Darwin's ideas do you cling to? Both of us accept that we evolved as he championed. Anything more?
dhw: Sometimes you say you accept evolution, but sometimes you insist that every innovation was specially designed and you subscribe directly to Creationism: “I think God creates species de novo in an evolving order.” I don’t know what you meant by an evolving order, but de novo could hardly be clearer. I accept common descent, the influence of the environment on speciation, survival as the driving force (which entails cooperation as well as competition), and natural selection as a neat term to explain the survival of organs and organisms (but NOT to explain speciation). I am only against random mutations as the cause of innovations, and Darwin’s insistence that “natura non facit saltus”.
Fine. Common descent is a step-wize development of more and more complexity. As above I view God as the driver designer.
Human evolution; "Little foot's" balance mechanism
dhw: Why do you think organisms cooperate if it’s not in order to improve their chances of survival?
DAVID: Cooperation helps survival, but you keep insisting survival drives evolution and that is a concept that is unproven.
And
DAVID: Survival is required for evolution to continue. Survival is designed into the process by God.
dhw: I would have thought that for most people the role of survival as a driving force is blindingly obvious etc. etc.
DAVID: Our difference is that I view God as driving evolution step by step which makes survival a non-driving force.
No it doesn’t. In your hypothesis, of course your God is the driving force behind the creation of life and evolution. The doer is the driving force behind the deed, and the reason for the deed is the driving force behind the doer. In your hypothesis, survival is the driving force behind your God’s decision to specially design whale fins, cuttlefish camouflage and monarch butterfly flight paths. The fact that you believe your always-in-control God specially designed these means of survival in order to provide econiches for life forms to eat one another (= your food argument on the genome thread) so that he could fill in 3.5+ billion years before specially designing the only thing he wanted to specially design – you and me – does not alter the obvious fact that survival is the reason for inventing means of survival. The reason for doing something is the driving force for doing it. And so even in your strange hypothesis of 3.5 billion years of divine procrastination, it is absurd to claim that “there is little real evidence that survival plays any role in evolution”, which was the starting point of this particular discussion.
You then asked me which of Darwin’s ideas I “cling” to, and I gave you a complete list of those I accepted and those I rejected.
DAVID: Fine. Common descent is a step-wize development of more and more complexity. As above I view God as the driver designer.
I know you do. Sometimes you even view God as having specially designed every step and every species “de novo” although you claim to believe in evolution and common descent. Anyway, you asked me which of Darwin’s ideas I “cling” to, and I answered you.
Human evolution; "Little foot's" balance mechanism
by David Turell , Wednesday, January 23, 2019, 19:28 (2129 days ago) @ dhw
dhw: Why do you think organisms cooperate if it’s not in order to improve their chances of survival?
DAVID: Cooperation helps survival, but you keep insisting survival drives evolution and that is a concept that is unproven.
And
DAVID: Survival is required for evolution to continue. Survival is designed into the process by God.dhw: I would have thought that for most people the role of survival as a driving force is blindingly obvious etc. etc.
DAVID: Our difference is that I view God as driving evolution step by step which makes survival a non-driving force.
dhw: No it doesn’t. In your hypothesis, of course your God is the driving force behind the creation of life and evolution. The doer is the driving force behind the deed, and the reason for the deed is the driving force behind the doer. In your hypothesis, survival is the driving force behind your God’s decision to specially design whale fins, cuttlefish camouflage and monarch butterfly flight paths.
Total misinterpretation of my clearly stated position. God's driving force is His purpose to produce humans through a process of evolving ever-complex organisms. Survival must be included in the progressive designs or evolution cannot proceed. This is a nuanced view that seems to escape you, probably because you do not have a view of God similar to mine.
dhw: The fact that you believe your always-in-control God specially designed these means of survival in order to provide econiches for life forms to eat one another (= your food argument on the genome thread) so that he could fill in 3.5+ billion years before specially designing the only thing he wanted to specially design – you and me – does not alter the obvious fact that survival is the reason for inventing means of survival. The reason for doing something is the driving force for doing it. And so even in your strange hypothesis of 3.5 billion years of divine procrastination, it is absurd to claim that “there is little real evidence that survival plays any role in evolution”, which was the starting point of this particular discussion.
Your usual trope. Of course God seems to have procrastinated if He decided to chose evolution as his means of creation. Why won't you allow Him the right to make that choice? It is what history tells us, and doesn't require your fanciful theories about God wildly human desires.
dhw: You then asked me which of Darwin’s ideas I “cling” to, and I gave you a complete list of those I accepted and those I rejected.DAVID: Fine. Common descent is a step-wize development of more and more complexity. As above I view God as the driver designer.
dhw: I know you do. Sometimes you even view God as having specially designed every step and every species “de novo” although you claim to believe in evolution and common descent. Anyway, you asked me which of Darwin’s ideas I “cling” to, and I answered you.
I don't understand you. My view of God's control is obviously a form of common descent, one you don't like, but that doesn't change its validity as a viewpoint.
Human evolution; "Little foot's" balance mechanism
dhw: I would have thought that for most people the role of survival as a driving force is blindingly obvious etc. etc.
DAVID: Our difference is that I view God as driving evolution step by step which makes survival a non-driving force.
dhw: No it doesn’t. In your hypothesis, of course your God is the driving force behind the creation of life and evolution. The doer is the driving force behind the deed, and the reason for the deed is the driving force behind the doer. In your hypothesis, survival is the driving force behind your God’s decision to specially design whale fins, cuttlefish camouflage and monarch butterfly flight paths.
DAVID: Total misinterpretation of my clearly stated position. God's driving force is His purpose to produce humans through a process of evolving ever-complex organisms. Survival must be included in the progressive designs or evolution cannot proceed. This is a nuanced view that seems to escape you, probably because you do not have a view of God similar to mine.
I certainly don’t share your view that your God specially designed whale fins, cuttlefish camouflage and monarch flight paths in order to produce humans through a process of “ever-complex” organisms, and like yourself I cannot understand why he would impose a 3.5+ billion-year schedule upon himself (see below) to create the only life form he wanted to create. But of course I agree that evolution could not have proceeded if every life form died out – regardless of where it was leading! That is why – even if your God exists and designed every single life form etc. – the reason for all the individual innovations, lifestyles and natural wonders that constitute the history of life and evolution is to improve chances of survival. And that is why it is absurd to claim that “there is little real evidence that survival plays any role in evolution”, which was the starting point of this particular discussion
DAVID: Your usual trope. Of course God seems to have procrastinated if He decided to chose evolution as his means of creation. Why won't you allow Him the right to make that choice? It is what history tells us, and doesn't require your fanciful theories about God wildly human desires.
If God exists, of course he chose evolution as his means of creation. What I am contesting is your right to insist that he only wanted to create H. sapiens, and imposed a 3.5+ billion-year waiting time on himself, and only created all the other life forms so that they could eat one another until his self-imposed waiting time was over. “Wildly human desires” are your mantra whenever I challenge your logic (not God’s), as in this exchange taken from the “Genome complexity” thread on the same subject:
dhw: Your idea is that your always-in-control God specially designed a bush of food to fill in 3.5+ billion years of life until he could specially design the only thing he wanted to design. I suggest that the helter-skelter bush is the result of him wishing to create a helter-skelter bush. We needn’t go into the “humanizing” reasons we both hypothesize.
DAVID: But all you have done is look for humanizing reasons. There is no reason for humans with consciousness to appear unless God desired that result of evolution.
If your God exists, there is no reason for the higgledy-piggledy bush to appear unless he desired that result of evolution. Why is that a “humanizing” reason, and the appearance of humans is not a “humanizing” reason. Why would he want a higgledy-piggledy bush to appear? I can’t give you a reason without “humanizing him”. Why would he want humans to appear? Give me a reason without “humanizing” him. You can’t. That’s why you came up with: he wants us to think about him, to have a relationship with him, to admire what he has created. And so it is perfectly reasonable to suggest that since history shows us a higgledy-piggledy bush, your God may have wanted a higgledy-piggledy bush, and we needn’t go into the “humanizing” reasons we both hypothesize.
dhw: You then asked me which of Darwin’s ideas I “cling” to, and I gave you a complete list of those I accepted and those I rejected.
DAVID: Fine. Common descent is a step-wize development of more and more complexity. As above I view God as the driver designer.
dhw: I know you do. Sometimes you even view God as having specially designed every step and every species “de novo” although you claim to believe in evolution and common descent. Anyway, you asked me which of Darwin’s ideas I “cling” to, and I answered you.
DAVID: I don't understand you. My view of God's control is obviously a form of common descent, one you don't like, but that doesn't change its validity as a viewpoint.
Your view changes from day to day. How can you reconcile common descent with “I think God creates species de novo in an evolving order” (January 16)? If he modifies existing species (= common descent), then speciation is not de novo!
Human evolution; "Little foot's" balance mechanism
by David Turell , Thursday, January 24, 2019, 21:07 (2128 days ago) @ dhw
dhw: In your hypothesis, of course your God is the driving force behind the creation of life and evolution. The doer is the driving force behind the deed, and the reason for the deed is the driving force behind the doer. In your hypothesis, survival is the driving force behind your God’s decision to specially design whale fins, cuttlefish camouflage and monarch butterfly flight paths.
DAVID: Total misinterpretation of my clearly stated position. God's driving force is His purpose to produce humans through a process of evolving ever-complex organisms. Survival must be included in the progressive designs or evolution cannot proceed. This is a nuanced view that seems to escape you, probably because you do not have a view of God similar to mine.
dhw: But of course I agree that evolution could not have proceeded if every life form died out – regardless of where it was leading! That is why – even if your God exists and designed every single life form etc. – the reason for all the individual innovations, lifestyles and natural wonders that constitute the history of life and evolution is to improve chances of survival. And that is why it is absurd to claim that “there is little real evidence that survival plays any role in evolution”, which was the starting point of this particular discussion
Have you presented any actual evidence?
dhw: Your idea is that your always-in-control God specially designed a bush of food to fill in 3.5+ billion years of life until he could specially design the only thing he wanted to design. I suggest that the helter-skelter bush is the result of him wishing to create a helter-skelter bush. We needn’t go into the “humanizing” reasons we both hypothesize.DAVID: But all you have done is look for humanizing reasons. There is no reason for humans with consciousness to appear unless God desired that result of evolution.
dhw: If your God exists, there is no reason for the higgledy-piggledy bush to appear unless he desired that result of evolution. Why is that a “humanizing” reason, and the appearance of humans is not a “humanizing” reason. Why would he want a higgledy-piggledy bush to appear? I can’t give you a reason without “humanizing him”. Why would he want humans to appear? Give me a reason without “humanizing” him. You can’t. That’s why you came up with: he wants us to think about him, to have a relationship with him, to admire what he has created. And so it is perfectly reasonable to suggest that since history shows us a higgledy-piggledy bush, your God may have wanted a higgledy-piggledy bush, and we needn’t go into the “humanizing” reasons we both hypothesize.
The h-p provides the necessary food. Of course God needed to create the bush.
dhw: I know you do. Sometimes you even view God as having specially designed every step and every species “de novo” although you claim to believe in evolution and common descent. Anyway, you asked me which of Darwin’s ideas I “cling” to, and I answered you.DAVID: I don't understand you. My view of God's control is obviously a form of common descent, one you don't like, but that doesn't change its validity as a viewpoint.
dhw: Your view changes from day to day. How can you reconcile common descent with “I think God creates species de novo in an evolving order” (January 16)? If he modifies existing species (= common descent), then speciation is not de novo!
My view is quite fixed. You misinterpret my use of de novo. Each species is a new species although it certainly may be a modification. It may have come from a previous form but it still is something new. I use it is the Latin sense of something new from something in the past.
Human evolution; "Little foot's" balance mechanism
DAVID: God's driving force is His purpose to produce humans through a process of evolving ever-complex organisms. Survival must be included in the progressive designs or evolution cannot proceed. This is a nuanced view that seems to escape you, probably because you do not have a view of God similar to mine.
dhw: But of course I agree that evolution could not have proceeded if every life form died out – regardless of where it was leading! That is why – even if your God exists and designed every single life form etc. – the reason for all the individual innovations, lifestyles and natural wonders that constitute the history of life and evolution is to improve chances of survival. And that is why it is absurd to claim that “there is little real evidence that survival plays any role in evolution”, which was the starting point of this particular discussion
DAVID: Have you presented any actual evidence?
What do you want me to do? Should I cut off the whale’s fins and tail, remove the cuttlefish’s camouflage, stop the monarch butterfly from migrating, go round snipping out the web-making equipment of 50,000 types of spider, and then report back to tell you how long they survive? You claim that your God specially designed all these innovations, lifestyles and natural wonders, and did so to enable the organisms to SURVIVE until his mysteriously self-imposed waiting time of 3.5+ billion years had elapsed, and only then could he design the only thing he wanted to design. "Have you presented any actual evidence?" If the purpose of an innovation, lifestyle or natural wonder (whether specially designed by your God or not) is to help the organism to survive, it is patently absurd to say that survival plays no role in evolution.
DAVID: My view of God's control is obviously a form of common descent, one you don't like, but that doesn't change its validity as a viewpoint.
dhw: Your view changes from day to day. How can you reconcile common descent with “I think God creates species de novo in an evolving order” (January 16)? If he modifies existing species (= common descent), then speciation is not de novo!
DAVID: My view is quite fixed. You misinterpret my use of de novo. Each species is a new species although it certainly may be a modification. It may have come from a previous form but it still is something new. I use it is the Latin sense of something new from something in the past.
A lot of your views are indeed fixed. Lots of species are now old, and so I presume you mean that each new species is a new species, which I suspect we would all agree on. But if you create something de novo, it means you create it from scratch, not that you modify something that already exists. Creationists believe that their God created each species separately, or de novo (= anew, afresh, from the beginning), whereas evolutionists believe that all species evolved out of earlier species. You are as aware of this as I am. Even with my limited knowledge of Latin, I don’t know how “de novo” can mean “from something in the past”.
Human evolution; "Little foot's" balance mechanism
by David Turell , Friday, January 25, 2019, 21:46 (2127 days ago) @ dhw
DAVID: Have you presented any actual evidence?
dhw: What do you want me to do? Should I cut off the whale’s fins and tail, remove the cuttlefish’s camouflage, stop the monarch butterfly from migrating, go round snipping out the web-making equipment of 50,000 types of spider, and then report back to tell you how long they survive? You claim that your God specially designed all these innovations, lifestyles and natural wonders, and did so to enable the organisms to SURVIVE until his mysteriously self-imposed waiting time of 3.5+ billion years had elapsed, and only then could he design the only thing he wanted to design. "Have you presented any actual evidence?" If the purpose of an innovation, lifestyle or natural wonder (whether specially designed by your God or not) is to help the organism to survive, it is patently absurd to say that survival plays no role in evolution.
Twisting and turning again. I never said it played NO role in evolution. To repeat: species must be designed to survive or evolutionary advances will stop. The driving force is a designer who is fully aware of the necessity of survival. I do not accept survival as a driving force, and I don't expect you to become a research scientist. Just find me a factual report that proves evolution is driven by survival. It is a Darwin concept, never proven, and I know you know that.
DAVID: My view of God's control is obviously a form of common descent, one you don't like, but that doesn't change its validity as a viewpoint.dhw: Your view changes from day to day. How can you reconcile common descent with “I think God creates species de novo in an evolving order” (January 16)? If he modifies existing species (= common descent), then speciation is not de novo!
DAVID: My view is quite fixed. You misinterpret my use of de novo. Each species is a new species although it certainly may be a modification. It may have come from a previous form but it still is something new. I use it is the Latin sense of something new from something in the past.
dhw: A lot of your views are indeed fixed. Lots of species are now old, and so I presume you mean that each new species is a new species, which I suspect we would all agree on. But if you create something de novo, it means you create it from scratch, not that you modify something that already exists. Creationists believe that their God created each species separately, or de novo (= anew, afresh, from the beginning), whereas evolutionists believe that all species evolved out of earlier species. You are as aware of this as I am. Even with my limited knowledge of Latin, I don’t know how “de novo” can mean “from something in the past”.
No need to argue about de novo. In Latin it is something new. Dictionaries support there usage: Roget's thesaurus : anew, afresh
Human evolution; "Little foot's" balance mechanism
DAVID: Have you presented any actual evidence?
dhw: What do you want me to do? Should I cut off the whale’s fins and tail, remove the cuttlefish’s camouflage, stop the monarch butterfly from migrating, go round snipping out the web-making equipment of 50,000 types of spider, and then report back to tell you how long they survive? You claim that your God specially designed all these innovations, lifestyles and natural wonders, and did so to enable the organisms to SURVIVE until his mysteriously self-imposed waiting time of 3.5+ billion years had elapsed, and only then could he design the only thing he wanted to design. "Have you presented any actual evidence?" If the purpose of an innovation, lifestyle or natural wonder (whether specially designed by your God or not) is to help the organism to survive, it is patently absurd to say that survival plays no role in evolution.
DAVID: Twisting and turning again. I never said it played NO role in evolution.
I haven’t got time to go through all your past posts, but this has been an ongoing theme. The quote I noted down for future reference was from 11 December under “Introducing the brain; complexity: autopilot: “As I see it there is little real evidence that survival plays any role in evolution, if humans are used as an example.” At the time, this had nothing to do with the subject under discussion, and I responded: “Why you keep harping on about survival is a mystery to me, except that it is part of your Darwinphobia.” But we needn’t quibble over it, since you continue to insist, as below, that survival is not a driving force:
DAVID: To repeat: species must be designed to survive or evolutionary advances will stop. The driving force is a designer who is fully aware of the necessity of survival. I do not accept survival as a driving force, and I don't expect you to become a research scientist. Just find me a factual report that proves evolution is driven by survival. It is a Darwin concept, never proven, and I know you know that.
Nothing is proven – not even the existence of God or the theory of evolution. Why have you ignored the point I put to you earlier? If there is a God, then of course he is the driving force behind life and evolution. That is not the issue. The doer is the driving force behind the deed, and the motive is the driving force behind the doer. If you set out to make a fortune, you are the driving force behind the business, and love of money is the driving force for your creating all the elements which will make the business successful. Whatever may have been your God’s motive in starting life and evolution, the purpose, motive or driving force for creating all the individual elements (innovations, lifestyles and natural wonders) – according to your own hypothesis – was to enable the organisms to survive. If purpose or motive is not a driving force, then I really don’t know what is.
dhw: How can you reconcile common descent with “I think God creates species de novo in an evolving order” (January 16)? If he modifies existing species (= common descent), then speciation is not de novo!
DAVID: You misinterpret my use of de novo. Each species is a new species although it certainly may be a modification. It may have come from a previous form but it still is something new. I use it is the Latin sense of something new from something in the past.
dhw: …if you create something de novo, it means you create it from scratch, not that you modify something that already exists. Creationists believe that their God created each species separately, or de novo (= anew, afresh, from the beginning), whereas evolutionists believe that all species evolved out of earlier species. You are as aware of this as I am. Even with my limited knowledge of Latin, I don’t know how “de novo” can mean “from something in the past”.
DAVID: No need to argue about de novo. In Latin it is something new. Dictionaries support there usage: Roget's thesaurus : anew, afresh.
Thank you for repeating the definition I already gave you in my answer (now bolded). Absolutely nothing to do with “something from the past”, and absolutely in line with Creationism as opposed to evolution. I presume your use of the term was simply a mistake, then, and you do believe in common descent as opposed to your God creating species de novo, so we can drop it.
Human evolution; "Little foot's" balance mechanism
by David Turell , Saturday, January 26, 2019, 18:43 (2126 days ago) @ dhw
DAVID: Twisting and turning again. I never said it [survival] played NO role in evolution.dhw: I haven’t got time to go through all your past posts, but this has been an ongoing theme. The quote I noted down for future reference was from 11 December under “Introducing the brain; complexity: autopilot: “As I see it there is little real evidence that survival plays any role in evolution, if humans are used as an example.” At the time, this had nothing to do with the subject under discussion, and I responded: “Why you keep harping on about survival is a mystery to me, except that it is part of your Darwinphobia.” But we needn’t quibble over it, since you continue to insist, as below, that survival is not a driving force:
DAVID: To repeat: species must be designed to survive or evolutionary advances will stop. The driving force is a designer who is fully aware of the necessity of survival. I do not accept survival as a driving force, and I don't expect you to become a research scientist. Just find me a factual report that proves evolution is driven by survival. It is a Darwin concept, never proven, and I know you know that.
dhw: Nothing is proven – not even the existence of God or the theory of evolution. Why have you ignored the point I put to you earlier? If there is a God, then of course he is the driving force behind life and evolution. That is not the issue. The doer is the driving force behind the deed, and the motive is the driving force behind the doer. If you set out to make a fortune, you are the driving force behind the business, and love of money is the driving force for your creating all the elements which will make the business successful. Whatever may have been your God’s motive in starting life and evolution, the purpose, motive or driving force for creating all the individual elements (innovations, lifestyles and natural wonders) – according to your own hypothesis – was to enable the organisms to survive. If purpose or motive is not a driving force, then I really don’t know what is.
We are close together, but there is a major nuance of difference. Survival is required but does not drive evolution to force new advances in complexity. I view God as the designer with the prime purpose to create beings with consciousness. That consciousness at the human level is not required for survival is demonstrated by all the other primates. I repeat survival as a driving force is not proven and never will be. I will continue to believe in a designer with an identifiable purpose.
Human evolution; "Little foot's" balance mechanism
dhw: […] Whatever may have been your God’s motive in starting life and evolution, the purpose, motive or driving force for creating all the individual elements (innovations, lifestyles and natural wonders) – according to your own hypothesis – was to enable the organisms to survive. If purpose or motive is not a driving force, then I really don’t know what is.
DAVID: We are close together, but there is a major nuance of difference. Survival is required but does not drive evolution to force new advances in complexity.
I did not say it forced advances in complexity – I do not regard fins as more complex than legs. But I believe that if the pre-whale’s legs turned into fins, that was because fins improved its chances of survival in water.
DAVID: I view God as the designer with the prime purpose to create beings with consciousness. That consciousness at the human level is not required for survival is demonstrated by all the other primates.
We have both agreed a thousand times that since bacteria have survived, NOTHING else was “required” for the survival of life itself. I don’t understand why suddenly you are confining evolution to humans. Once multicellular organisms evolved, there was diversity, and all kinds of innovations were designed (by your God or by my cell communities) to improve chances of survival – leading to all the different econiches (see below under “Neanderthal”) that existed thousands of millions of years before humans arrived.
DAVID: I repeat survival as a driving force is not proven and never will be. I will continue to believe in a designer with an identifiable purpose.
I repeat: (a) none of our hypotheses about God or about evolution are “proven”, and (b) if you think the purpose of or motive for an invention is not a driving force, then I don’t know what is. And if God exists, of course he has a purpose, but you are in no better a position than I am to identify it or to read the thoughts behind his method for achieving his purpose.
Under “Neanderthal”
QUOTE: "And so we have consistently mistaken survival and extinction with biological superiority or inferiority. That is why we have incessantly sought differences to explain our observations. We are here and they are not and so we must seek differences to explain the data. (David's bold)
DAVID: […] Note my bold. Survival does not indicate natural superiority. We still do not know all the reasons for survival and therefore for evolution to newer 'better' forms. Evolution is not driven by a need for survival. On the other hand it is obvious there is a drive for evolution to proceed.
The fact that we don’t know why Neanderthals as such did not survive has absolutely nothing to do with the reason why new organs, lifestyles and natural wonders have originated throughout the history of evolution. Superiority or inferiority are not the point either. As you yourself keep emphasizing, all econiches depend on a hierarchy. For the econiche to survive, the “inferior” organisms must also survive or the “superior” ones will perish. You simply refuse to recognize the obvious fact that if innovations, lifestyles and natural wonders help organisms to survive, then survival is the obvious reason for their existence, no matter how they came into being. And it is patently absurd to say that the reason for something coming into existence is not a driving force.
Human evolution; "Little foot's" balance mechanism
by David Turell , Sunday, January 27, 2019, 19:44 (2125 days ago) @ dhw
DAVID: We are close together, but there is a major nuance of difference. Survival is required but does not drive evolution to force new advances in complexity.
dhw: I did not say it forced advances in complexity – I do not regard fins as more complex than legs. But I believe that if the pre-whale’s legs turned into fins, that was because fins improved its chances of survival in water.
It seems you have just agreed survival does not drive evolution.
dhw: I repeat: (a) none of our hypotheses about God or about evolution are “proven”, and (b) if you think the purpose of or motive for an invention is not a driving force, then I don’t know what is. And if God exists, of course he has a purpose, but you are in no better a position than I am to identify it or to read the thoughts behind his method for achieving his purpose.
I'm not reading more than He desired to create humans. And I accept His choice in evolving us.
Under “Neanderthal”
QUOTE: "And so we have consistently mistaken survival and extinction with biological superiority or inferiority. That is why we have incessantly sought differences to explain our observations. We are here and they are not and so we must seek differences to explain the data. (David's bold)DAVID: […] Note my bold. Survival does not indicate natural superiority. We still do not know all the reasons for survival and therefore for evolution to newer 'better' forms. Evolution is not driven by a need for survival. On the other hand it is obvious there is a drive for evolution to proceed.
dhw: The fact that we don’t know why Neanderthals as such did not survive has absolutely nothing to do with the reason why new organs, lifestyles and natural wonders have originated throughout the history of evolution. Superiority or inferiority are not the point either. As you yourself keep emphasizing, all econiches depend on a hierarchy. For the econiche to survive, the “inferior” organisms must also survive or the “superior” ones will perish. You simply refuse to recognize the obvious fact that if innovations, lifestyles and natural wonders help organisms to survive, then survival is the obvious reason for their existence, no matter how they came into being. And it is patently absurd to say that the reason for something coming into existence is not a driving force.
Old material. Obviously survival must occur or nothing will evolve. Of course thre is a driving force. God the designer
Human evolution; "Little foot's" balance mechanism
DAVID: We are close together, but there is a major nuance of difference. Survival is required but does not drive evolution to force new advances in complexity.
dhw: I did not say it forced advances in complexity – I do not regard fins as more complex than legs. But I believe that if the pre-whale’s legs turned into fins, that was because fins improved its chances of survival in water.
DAVID: It seems you have just agreed survival does not drive evolution.
How do you reach that conclusion? If the reason for legs turning into fins is to improve chances of survival, then the evolution of fins is driven by the drive to survive or to improve chances of survival!
dhw: I repeat: (a) none of our hypotheses about God or about evolution are “proven”, and (b) if you think the purpose of or motive for an invention is not a driving force, then I don’t know what is. And if God exists, of course he has a purpose, but you are in no better a position than I am to identify it or to read the thoughts behind his method for achieving his purpose.
DAVID: I'm not reading more than He desired to create humans. And I accept His choice in evolving us.
You keep telling us that his desire to create humans was his one and only purpose, and his method was to spend 3.5+ billion years not creating humans. You “accept” that he follows your own non-logic. And you still haven’t told me why you think the motive or purpose for doing something is not a driving force.
dhw: The fact that we don’t know why Neanderthals as such did not survive has absolutely nothing to do with the reason why new organs, lifestyles and natural wonders have originated throughout the history of evolution. Superiority or inferiority are not the point either. As you yourself keep emphasizing, all econiches depend on a hierarchy. For the econiche to survive, the “inferior” organisms must also survive or the “superior” ones will perish. You simply refuse to recognize the obvious fact that if innovations, lifestyles and natural wonders help organisms to survive, then survival is the obvious reason for their existence, no matter how they came into being. And it is patently absurd to say that the reason for something coming into existence is not a driving force.
DAVID: Old material. Obviously survival must occur or nothing will evolve. Of course thre is a driving force. God the designer.
And you persist in ignoring the point that I keep making over and over again: yes, if God exists he must have created life and evolution and in that sense he is the driving force. But the purpose of means of survival is to enable organisms to survive, so even if he designed every single one, their purpose was survival. Now please tell us at last why you think the purpose or motive for designing something is not a driving force.
Human evolution; "Little foot's" balance mechanism
by David Turell , Monday, January 28, 2019, 14:39 (2124 days ago) @ dhw
dhw: I repeat: (a) none of our hypotheses about God or about evolution are “proven”, and (b) if you think the purpose of or motive for an invention is not a driving force, then I don’t know what is. And if God exists, of course he has a purpose, but you are in no better a position than I am to identify it or to read the thoughts behind his method for achieving his purpose.
DAVID: I'm not reading more than He desired to create humans. And I accept His choice in evolving us.
dhw: You keep telling us that his desire to create humans was his one and only purpose, and his method was to spend 3.5+ billion years not creating humans. You “accept” that he follows your own non-logic. And you still haven’t told me why you think the motive or purpose for doing something is not a driving force.
I have accepted that God's purpose or motive was to evolve human beings. That is a driving force from my viewpoint.
dhw: The fact that we don’t know why Neanderthals as such did not survive has absolutely nothing to do with the reason why new organs, lifestyles and natural wonders have originated throughout the history of evolution. Superiority or inferiority are not the point either. As you yourself keep emphasizing, all econiches depend on a hierarchy. For the econiche to survive, the “inferior” organisms must also survive or the “superior” ones will perish. You simply refuse to recognize the obvious fact that if innovations, lifestyles and natural wonders help organisms to survive, then survival is the obvious reason for their existence, no matter how they came into being. And it is patently absurd to say that the reason for something coming into existence is not a driving force.DAVID: Old material. Obviously survival must occur or nothing will evolve. Of course thre is a driving force. God the designer.
dhw: And you persist in ignoring the point that I keep making over and over again: yes, if God exists he must have created life and evolution and in that sense he is the driving force. But the purpose of means of survival is to enable organisms to survive, so even if he designed every single one, their purpose was survival. Now please tell us at last why you think the purpose or motive for designing something is not a driving force.
And you persist in not recognizing that evolution is a process that would grind to a halt unless the ability to survive is built into each successive level of new organisms.
Human evolution; "Little foot's" balance mechanism
dhw: You keep telling us that his desire to create humans was his one and only purpose, and his method was to spend 3.5+ billion years not creating humans. You “accept” that he follows your own non-logic. And you still haven’t told me why you think the motive or purpose for doing something is not a driving force.
DAVID: I have accepted that God's purpose or motive was to evolve human beings. That is a driving force from my viewpoint.
You have not “accepted” it, you believe it, but if it’s true, then of course that would be a driving force. But according to you, his purpose or motive in designing whale fins, cuttlefish camouflage and the monarch’s flight path was to enable them to survive so life could go on for 3.5+ billion years until he could design the only thing he wanted to design. Whatever may be the purpose or motive for doing something is its driving force. Once again, if God exists, he is the driving force behind life and evolution, and his wish to enable organisms to survive is the driving force behind what you believe to be the special designs that enable them to do so.
dhw: […] you persist in ignoring the point that I keep making over and over again: yes, if God exists he must have created life and evolution and in that sense he is the driving force. But the purpose of means of survival is to enable organisms to survive, so even if he designed every single one, their purpose was survival. […]
DAVID: And you persist in not recognizing that evolution is a process that would grind to a halt unless the ability to survive is built into each successive level of new organisms.
Of course I recognize that evolution would have ended if new organisms had not survived! How does that come to mean that the purpose or motive behind each individual evolutionary change was not survival? And how does that lead to your conclusion that the purpose or motive for change is not a driving force?
Human evolution; "Little foot's" balance mechanism
by David Turell , Tuesday, January 29, 2019, 17:36 (2123 days ago) @ dhw
dhw: You keep telling us that his desire to create humans was his one and only purpose, and his method was to spend 3.5+ billion years not creating humans. You “accept” that he follows your own non-logic. And you still haven’t told me why you think the motive or purpose for doing something is not a driving force.
DAVID: I have accepted that God's purpose or motive was to evolve human beings. That is a driving force from my viewpoint.
dhw: You have not “accepted” it, you believe it, but if it’s true, then of course that would be a driving force. But according to you, his purpose or motive in designing whale fins, cuttlefish camouflage and the monarch’s flight path was to enable them to survive so life could go on for 3.5+ billion years until he could design the only thing he wanted to design. Whatever may be the purpose or motive for doing something is its driving force. Once again, if God exists, he is the driving force behind life and evolution, and his wish to enable organisms to survive is the driving force behind what you believe to be the special designs that enable them to do so.
It seems you are understanding what I believe. It is not illogical.
dhw: […] you persist in ignoring the point that I keep making over and over again: yes, if God exists he must have created life and evolution and in that sense he is the driving force. But the purpose of means of survival is to enable organisms to survive, so even if he designed every single one, their purpose was survival. […]DAVID: And you persist in not recognizing that evolution is a process that would grind to a halt unless the ability to survive is built into each successive level of new organisms.
dhw: Of course I recognize that evolution would have ended if new organisms had not survived! How does that come to mean that the purpose or motive behind each individual evolutionary change was not survival? And how does that lead to your conclusion that the purpose or motive for change is not a driving force?
The driving force is God using evolution to create humans. Survival is simply a secondary requirement as you admit.
Human evolution; how our eyes see light-dark contrast
by David Turell , Tuesday, January 29, 2019, 23:06 (2123 days ago) @ David Turell
By little unnoticed movements:
https://cosmosmagazine.com/biology/we-see-contrast-because-our-eyes-are-always-moving
"Contrast sensitivity function – which is different to visual acuity – is the minimum amount of light and dark that we need to see to detect an object or pattern.
"Until now, researchers have thought that seeing contrast relies on eye optics and brain processing. However, a new study, published in the journal eLife, reveals that tiny eye movements play a critical role.
“'Historically these eye movements have been pretty much ignored,” says Michele Rucci, professor of brain and cognitive sciences at the University of Rochester in the US. “But what seems to be happening is that they are contributing to vision in a number of different ways, including contrast sensitivity function.”
"If we fix our eyes on a single point, the world may appear still. But microscopically, our eyes are always moving – known as “fixational eye movements”. Without these movements continually refreshing visual input to the retina, an image can fade from view.
"To test the role of eye movements in detecting contrast, the researchers showed five females aged 21-31 with normal vision gratings with black and white stripes, making them progressively thinner – known as spatial frequency – until volunteers could no longer see separate bars.
"When they simulated the task in a computer model of the retina and associated neurons, the researchers found that contrast sensitivity was only achieved when they included the eye movements.
“'When we don’t include this movement factor in the computer model, the simulated neurons don’t give the same responses that the subjects do,” says Rucci.
"It’s a bit like the system involved in our sense of touch, explains lead author Antonino Casile from the Italian Institute of Technology.
"To feel the texture of a surface, it is not enough to just touch it – we also need to move our fingers along the object. We process information from the interaction between our fingertips’ tactile sensors and movement.
'Similarly, contrast sensitivity results from the interaction between the sensory process in the brain’s visual system and the motor process of eye movement, Casile says.
"The findings, write the authors, “are highly robust, bear multiple consequences, and lead to important predictions”.
“'Vision isn’t just taking an image and processing it via neurons,” says Rucci. “The visual system uses an active scheme to extract and code information. We see because our eyes are always moving, even if we don’t know it.'”
Comment: I'm sure previous ancestors have this same ability long before humans arrived. I am aware that my eyes are constantly moving, if only to keep them moist. but I never noticed tiny changes As described.
Human evolution; how our eyes see light intensity
by David Turell , Monday, August 19, 2019, 00:24 (1922 days ago) @ David Turell
A toally new cell function is described:
https://www.sciencedaily.com/releases/2019/08/190818101642.htm
"Scientists are shedding new light on the importance of light-sensing cells in the retina that process visual information. The researchers isolated the functions of melanopsin cells and demonstrated their crucial role in the perception of visual environment. This ushers in a new understanding of the biology of the eye and how visual information is processed.
"The back of the human eye is lined with the retina, a layer of various types of cells, called photoreceptors, that respond to different amounts of light. The cells that process a lot of light are called cones and those that process lower levels of light are named rods.
Up until recently, researchers have thought that when light struck the retina, rods and cones were the only two kinds of cells that react. Recent discoveries have revealed an entirely new type of cells, called intrinsically photosensitive retinal ganglion cells (ipRGCs). Unlike rods and cones, ipRGCs contain melanopsin, a photopigment that is sensitive to light. While it has been established that ipRGCs are involved in keeping the brain's internal clock in sync with changes in daylight, their importance in the detection of the amount of light had not yet been well understood.
***
"In the study, the authors showed how cones and melanopsin combine to allow the perception of brightness. In order to better assess the contribution of melanopsin to the detection of light, the melanopsin's signals were isolated from cones and rods. This separation allowed for more accurate observation of the melanopsin signal alone. Visual stimuli were carefully designed and positioned in order to specifically stimulate the light-sensitive chemical. Also, the researchers used tracking software to measure study participants' pupil diameters under each visual stimulus. This served as a way to determine the relationship between brightness perception and the actual visual stimulus intensity on the retina.
"The researchers were able to show that the varying brightness levels of an image that was perceived is a sum of the melanopsin response and the response that is generated by the cones. The former is a linear readout and the latter is not. The results also show that melanopsin is not a minor contributor in brightness perception. Rather, it is a crucial player in brightness perception."
Comment: The retina is shown to be even more complex in this newly recognized cell with its very special light sensing protein. Not by chance.
Human evolution; how our brains create images
by David Turell , Wednesday, August 21, 2019, 18:55 (1919 days ago) @ David Turell
A complex relationship with the visual cortex:
https://www.quantamagazine.org/a-mathematical-model-unlocks-the-secrets-of-vision-20190...
"This is the great mystery of human vision: Vivid pictures of the world appear before our mind’s eye, yet the brain’s visual system receives very little information from the world itself. Much of what we “see” we conjure in our heads.
“'A lot of the things you think you see you’re actually making up,” said Lai-Sang Young, a mathematician at New York University. “You don’t actually see them.”
***
"The eye acts as a lens. It receives light from the outside world and projects a scale replica of our visual field onto the retina, which sits in the back of the eye. The retina is connected to the visual cortex, the part of the brain in the back of the head.
"However, there’s very little connectivity between the retina and the visual cortex. For a visual area roughly one-quarter the size of a full moon, there are only about 10 nerve cells connecting the retina to the visual cortex. These cells make up the LGN, or lateral geniculate nucleus, the only pathway through which visual information travels from the outside world into the brain.
"Not only are LGN cells scarce — they can’t do much either. LGN cells send a pulse to the visual cortex when they detect a change from dark to light, or vice versa, in their tiny section of the visual field. And that’s all. The lighted world bombards the retina with data, but all the brain has to go on is the meager signaling of a tiny collection of LGN cells.
***
“'But the brain doesn’t take a picture, the retina does, and the information passed from the retina to the visual cortex is sparse.”
"But then the visual cortex goes to work. While the cortex and the retina are connected by relatively few neurons, the cortex itself is dense with nerve cells. For every 10 LGN neurons that snake back from the retina, there are 4,000 neurons in just the initial “input layer” of the visual cortex — and many more in the rest of it. This discrepancy suggests that the brain heavily processes the little visual data it does receive.
“'The visual cortex has a mind of its own,” Shapley said.
***
"These “feed forward” models were easier to create, but they ignored the plain implications of the anatomy of the cortex — which suggested “feedback” loops had to be a big part of the story.
***
"Young, Shapley and Chariker demonstrated that their feedback-rich model was able to reproduce the orientation of edges in objects — from vertical to horizontal and everything in between — based on only slight changes in the weak LGN input coming into the model.
“[They showed] that you can generate all orientations in the visual world using just a few neurons connecting to other neurons,” Angelucci said.
***
"In 2018, the three researchers published a second paper in which they demonstrated that the same model that can detect edges can also reproduce an overall pattern of pulse activity in the cortex known as the gamma rhythm. (It’s similar to what you see when swarms of fireflies flash in collective patterns.)
"They have a third paper under review that explains how the visual cortex perceives changes in contrast. Their explanation involves a mechanism by which excitatory neurons reinforce each other’s activity, an effect like the gathering fervor in a dance party. It’s the type of ratcheting up that’s necessary if the visual cortex is going to create full images from sparse input data.
***
"While their model is far from uncovering the full mystery of vision, it is a step in the right direction — the first model to try and decipher vision in a biologically plausible way.
“People hand-waved about that point for a long time,” said Jonathan Victor, a neuroscientist at Cornell University. “Showing you can do it in a model that fits the biology is a real triumph.'”
Comment: Babies see upside down and backward, but their brains are gradually taught to see reality. The visual cortex learns over time to effectively make the pictures. No 'free will' folks will point to this as proof they are right. But this is the only way a biological system can give proper results.
Human evolution; the brain differs from all others
by David Turell , Thursday, August 22, 2019, 01:03 (1918 days ago) @ David Turell
A newly studied 20 myo monkey brain reveals clues as to brain evolution:
https://cosmosmagazine.com/palaeontology/lifting-the-lid-on-primate-brains?utm_source=C...
"A fossilised primate skull the size of a chicken egg has yielded insights into how primate brains – including our own – evolved.
"The 20-million-year-old near-complete skull is a rare specimen. It belongs to Chilecebus carrascoensis, a primate that scampered around the Chilean Andes during the Miocene.
"The species is a member of the New World monkeys, or platyrrhines, a group found in Central and South America which today includes marmosets, capuchins and spider monkeys.
***
"Weighing in at around eight grams, Chilecebus had a brain roughly the size of a marmoset’s.
However, unlike a marmoset’s brain, which has quite a smooth surface, Chilecebus’s brain had seven pairs of grooves – sulci – on its surface.
"The presence of sulci is usually associated with larger, more cognitively advanced brains. The Chilecebus brain suggests size and brain folds don’t go hand in hand.
"Other anatomical features also seem to evolve independently.
***
"The findings support the idea that the primate brain evolves in a complex “mosaic” fashion, with different functional regions evolving independently of others.
"New World monkeys split from the other main group of primates, the catarrhines, more than 40 million years ago. This group includes the Old World monkeys of Asia and Africa – baboons and mandrils and the like – and apes, to which our own lineage belongs.
"In both groups, brain size has increased over time – a situation of convergent evolution.
But the comparison also reveals just how weird human brains are.
“'Only within the human lineage are the brains exceptionally enlarged,” says Ni. Human brains enlarged three times more than would be predicted based on the evolutionary trajectory of other lineages". (my bold)
Comment: Note my bold. Our brain evolved in a different trajectory.
Human evolution; how our brains create images
by David Turell , Monday, September 30, 2019, 19:31 (1879 days ago) @ David Turell
More studies on how the brain helps us see what we need to see, by pruning away the extraneous
objects:
https://www.quantamagazine.org/your-brain-chooses-what-to-let-you-see-20190930/
"Scientists have long known that our sensory processing must automatically screen out extraneous inputs — otherwise, we couldn’t experience the world as we do. When we look at our surroundings, for instance, our perceived field of view holds steady or moves smoothly with our gaze. But the eye is also constantly making small movements, or saccades; our visual system has to subtract that background jitter from what we see.
“'Automatic suppressive types of mechanisms take place … through large swaths of the brain,” said Richard Krauzlis, a neuroscientist at the National Eye Institute at the National Institutes of Health in Maryland. “Basically all over the place".
"And automatic background subtraction, it turns out, can also manifest in intriguing, unexpected ways. Take a counterintuitive finding that Tadin and his colleagues made in 2003: We’re good at perceiving the movements of small objects, but if those objects are simply made bigger, we find it much more difficult to detect their motion.
***
"The brain prioritizes the detection of objects that are more important for us to see, and those tend to be smaller. To a hawk hunting for its next meal, a mouse suddenly darting through a field matters more than the swaying motion of the grass and trees around it. As a result, Tadin and his team discovered, the brain suppresses information about the movement of the background — and as a side effect, it has more difficulty perceiving the movements of larger objects, because it treats them as a kind of background, too.
***
"Other researchers had previously reported that there’s not much difference between how well seniors observe the motion of a small object and the motion of a larger one. Because of this, Tadin and his colleagues predicted that older people would have problems spotting small moving objects against a moving backdrop — and that’s exactly what they found. Still, with a few weeks’ training, the test subjects got much better at recognizing that motion.
***
"What these results highlighted, he added, is that our sensitivity to larger moving objects is lower “because that’s the strategy our brain uses to make smaller moving objects against those backgrounds stand out more.”
It’s the same strategy (executed by a different mechanism) that the brain uses in goal-directed attentional processes: It gets rid of information that’s distracting or less useful in order to make the more relevant inputs stand out.
“'Before attention gets to do its job,” Tadin said, “there’s already a lot of pruning of information.” For motion perception, that pruning has to happen automatically because it needs to be done very quickly. “Attention can do the same thing in much smarter and more flexible ways, but not so effortlessly.”
"Together, these processes — both the automatic bottom-up ones and the more conscious top-down ones — generate the brain’s internal representation of its environment. It is what Ian Fiebelkorn, a cognitive neuroscientist at Princeton University, refers to as a “priority map,” with peaks and valleys that dictate where attentional resources should be aimed.
Through learning and training, he said, top-down goals continue to “manipulate that map, amplifying or suppressing the peaks” that represent salient properties of a stimulus.
"When it comes to how and what we perceive, Tadin said, “there’s a lot going on behind the scenes that we just take for granted.'”
Comment: However secondhand the brain makes our perceptions, we successfully navigate our environment as our progress shows. As a biological representation of our surroundings, it works, and that is all that counts.
Human evolution; "Little foot's" balance mechanism
DAVID: I have accepted that God's purpose or motive was to evolve human beings. That is a driving force from my viewpoint.
dhw: You have not “accepted” it, you believe it, but if it’s true, then of course that would be a driving force. But according to you, his purpose or motive in designing whale fins, cuttlefish camouflage and the monarch’s flight path was to enable them to survive so life could go on for 3.5+ billion years until he could design the only thing he wanted to design. Whatever may be the purpose or motive for doing something is its driving force. Once again, if God exists, he is the driving force behind life and evolution, and his wish to enable organisms to survive is the driving force behind what you believe to be the special designs that enable them to do so.
DAVID: It seems you are understanding what I believe. It is not illogical.
No it’s not. It is totally logical that the doer is the driving force behind the action, and the purpose is the driving force behind the doer. The purpose of fins, camouflage and migration is survival, and it is therefore illogical to say that survival is not a driving force in evolution. Thank you. Your other illogicality is dealt with on the “Big brain” thread.
Human evolution; "Little foot's" balance mechanism
by David Turell , Wednesday, January 30, 2019, 17:26 (2122 days ago) @ dhw
DAVID: I have accepted that God's purpose or motive was to evolve human beings. That is a driving force from my viewpoint.
dhw: You have not “accepted” it, you believe it, but if it’s true, then of course that would be a driving force. But according to you, his purpose or motive in designing whale fins, cuttlefish camouflage and the monarch’s flight path was to enable them to survive so life could go on for 3.5+ billion years until he could design the only thing he wanted to design. Whatever may be the purpose or motive for doing something is its driving force. Once again, if God exists, he is the driving force behind life and evolution, and his wish to enable organisms to survive is the driving force behind what you believe to be the special designs that enable them to do so.
DAVID: It seems you are understanding what I believe. It is not illogical.
dhw: No it’s not. It is totally logical that the doer is the driving force behind the action, and the purpose is the driving force behind the doer. The purpose of fins, camouflage and migration is survival, and it is therefore illogical to say that survival is not a driving force in evolution. Thank you. Your other illogicality is dealt with on the “Big brain” thread.
You have the argument totally backward. I accept that God is the doer and He wants to evolve humans. Survival has to be designed into each stage or evolution stops. Survival is required but the driver is God. It is illogical to you because you do not see the driving mechanism as I do.
Human evolution; "Little foot's" balance mechanism
dhw: […] if God exists, he is the driving force behind life and evolution, and his wish to enable organisms to survive is the driving force behind what you believe to be the special designs that enable them to do so.
DAVID: It seems you are understanding what I believe. It is not illogical.
dhw: No it’s not. It is totally logical that the doer is the driving force behind the action, and the purpose is the driving force behind the doer. The purpose of fins, camouflage and migration is survival, and it is therefore illogical to say that survival is not a driving force in evolution. Thank you. Your other illogicality is dealt with on the “Big brain” thread.
DAVID: You have the argument totally backward. I accept that God is the doer and He wants to evolve humans.
Not “accept”. These are your beliefs. For argument’s sake, I am accepting God’s existence, but a) questioning your belief that his sole purpose was to produce H. sapiens (see “Big brain evolution”), and on this thread b) questioning your belief that survival is not a driving force in the process of evolution.
DAVID: Survival has to be designed into each stage or evolution stops. Survival is required but the driver is God. It is illogical to you because you do not see the driving mechanism as I do.
Of course life has to survive or it stops. Once more: I see TWO driving mechanisms in your scenario: 1) Your God as the creator is the driving force behind life and evolution. 2) The reason for his designing all the innovations, lifestyles and natural wonders is to ensure that life SURVIVES. The reason for doing something is a driving force. Concrete example: if, as you believe, your God designed pre-whale fins, the reason for his doing so was to enable the pre-whale to improve its chances of survival in the water. How can you possibly argue that the reason for doing something is not a driving force?
Human evolution; "Little foot's" balance mechanism
by David Turell , Thursday, January 31, 2019, 14:54 (2121 days ago) @ dhw
dhw: […] if God exists, he is the driving force behind life and evolution, and his wish to enable organisms to survive is the driving force behind what you believe to be the special designs that enable them to do so.
DAVID: It seems you are understanding what I believe. It is not illogical.
dhw: No it’s not. It is totally logical that the doer is the driving force behind the action, and the purpose is the driving force behind the doer. The purpose of fins, camouflage and migration is survival, and it is therefore illogical to say that survival is not a driving force in evolution. Thank you. Your other illogicality is dealt with on the “Big brain” thread.
DAVID: You have the argument totally backward. I accept that God is the doer and He wants to evolve humans.
Not “accept”. These are your beliefs. For argument’s sake, I am accepting God’s existence, but a) questioning your belief that his sole purpose was to produce H. sapiens (see “Big brain evolution”), and on this thread b) questioning your belief that survival is not a driving force in the process of evolution.
DAVID: Survival has to be designed into each stage or evolution stops. Survival is required but the driver is God. It is illogical to you because you do not see the driving mechanism as I do.
dhw: Of course life has to survive or it stops. Once more: I see TWO driving mechanisms in your scenario: 1) Your God as the creator is the driving force behind life and evolution. 2) The reason for his designing all the innovations, lifestyles and natural wonders is to ensure that life SURVIVES. The reason for doing something is a driving force. Concrete example: if, as you believe, your God designed pre-whale fins, the reason for his doing so was to enable the pre-whale to improve its chances of survival in the water. How can you possibly argue that the reason for doing something is not a driving force?
Wrong nuance of meaning. When you drive your ancient VW you are careful not to crash. That is caution about necessary survival. God drives evolution with the same caution about survival of the organism s created.
Human evolution; "Little foot's" balance mechanism
dhw: Of course life has to survive or it stops. Once more: I see TWO driving mechanisms in your scenario: 1) Your God as the creator is the driving force behind life and evolution. 2) The reason for his designing all the innovations, lifestyles and natural wonders is to ensure that life SURVIVES. The reason for doing something is a driving force. Concrete example: if, as you believe, your God designed pre-whale fins, the reason for his doing so was to enable the pre-whale to improve its chances of survival in the water. How can you possibly argue that the reason for doing something is not a driving force?
DAVID: Wrong nuance of meaning. When you drive your ancient VW you are careful not to crash. That is caution about necessary survival. God drives evolution with the same caution about survival of the organism s created.
I don’t think this image helps us very much, but hey ho. The driving force behind the design of brakes, lights, windscreen wipers, seat belts etc. was to improve my chances of survival (and those of other drivers, pedestrians etc.) as I go hurtling along through streets, traffic, darkness, rain and snow. Meanwhile, back to your hypothesis, in which the driving force behind your God’s design of fins, camouflage and migration routes was to improve survival chances for whales, cuttlefish and monarch butterflies, just as apparently he designed my late wife’s pelvis, my hunter’s/escaper’s legs, and now even our skin colour (see below) to improve our chances of survival. Yes, if your God exists he is the driving force behind life and evolution. But why do you refuse to acknowledge that the purpose behind a design is also a driving force?
Under “skin color”
QUOTES: "Why is folate so important? The nutrient plays a role in DNA activities, but its major impact is on evolutionary fitness — one’s ability to survive and reproduce — through fetal development.
"[..] vitamin D became a problem. Like folate, this vitamin is important for evolutionary fitness. It facilitates absorption of calcium, necessary for healthy bones and immunity.
"A range of skin colors evolved at different times, in different populations, as human spread across the globe. In addition to these genetic biological changes, groups have also developed cultural adaptations to deal with variable sunlight. For instance, we can consume diets rich in folate and vitamin D. We can also build shelters, wear clothing and slather sunscreen to block UV rays."
All of which make it crystal clear that the purpose is survival. The driving force behind our building of shelters, our clothes and our sunscreen is our desire to improve our chances of survival, and likewise the driving force behind variations of skin colors.
DAVID: These studies certainly appear to explain why our species adapted light or dark skin. Since folate is so important to reproduction, I would suspect it was more of a driving force than Vitamin D in producing this adaptation. (dhw’s bold)
And so the requirement for folate to aid reproduction was a “driving force”. Just like the requirement for fins to aid swimming etc. etc. Crystal clear again.
Human evolution; "Little foot's" balance mechanism
by David Turell , Friday, February 01, 2019, 14:44 (2120 days ago) @ dhw
DAVID: Wrong nuance of meaning. When you drive your ancient VW you are careful not to crash. That is caution about necessary survival. God drives evolution with the same caution about survival of the organism s created.
dhw: I don’t think this image helps us very much, but hey ho. The driving force behind the design of brakes, lights, windscreen wipers, seat belts etc. was to improve my chances of survival (and those of other drivers, pedestrians etc.) as I go hurtling along through streets, traffic, darkness, rain and snow. Meanwhile, back to your hypothesis, in which the driving force behind your God’s design of fins, camouflage and migration routes was to improve survival chances for whales, cuttlefish and monarch butterflies, just as apparently he designed my late wife’s pelvis, my hunter’s/escaper’s legs, and now even our skin colour (see below) to improve our chances of survival. Yes, if your God exists he is the driving force behind life and evolution. But why do you refuse to acknowledge that the purpose behind a design is also a driving force?
Because I view God as the driver, and survival a secondary requirement since evolving organisms must survive for each advance to occur. Again a difference in nuance.
dhw: Under “skin color”
QUOTES: "Why is folate so important? The nutrient plays a role in DNA activities, but its major impact is on evolutionary fitness — one’s ability to survive and reproduce — through fetal development."[..] vitamin D became a problem. Like folate, this vitamin is important for evolutionary fitness. It facilitates absorption of calcium, necessary for healthy bones and immunity.
"A range of skin colors evolved at different times, in different populations, as human spread across the globe. In addition to these genetic biological changes, groups have also developed cultural adaptations to deal with variable sunlight. For instance, we can consume diets rich in folate and vitamin D. We can also build shelters, wear clothing and slather sunscreen to block UV rays."
dhw: All of which make it crystal clear that the purpose is survival. The driving force behind our building of shelters, our clothes and our sunscreen is our desire to improve our chances of survival, and likewise the driving force behind variations of skin colors.
DAVID: These studies certainly appear to explain why our species adapted light or dark skin. Since folate is so important to reproduction, I would suspect it was more of a driving force than Vitamin D in producing this adaptation. (dhw’s bold)
dhw: And so the requirement for folate to aid reproduction was a “driving force”. Just like the requirement for fins to aid swimming etc. etc. Crystal clear again.
Immediate driving forces are part of the pattern of survival for the overall purpose of evolution to the goal, humans. Crystal clear.
Human evolution; "Little foot's" balance mechanism
dhw: Yes, if your God exists he is the driving force behind life and evolution. But why do you refuse to acknowledge that the purpose behind a design is also a driving force?
DAVID: Because I view God as the driver, and survival a secondary requirement since evolving organisms must survive for each advance to occur. Again a difference in nuance.
DAVID (re skin colour): These studies certainly appear to explain why our species adapted light or dark skin. Since folate is so important to reproduction, I would suspect it was more of a driving force than Vitamin D in producing this adaptation. (dhw’s bold)
dhw: And so the requirement for folate to aid reproduction was a “driving force”. Just like the requirement for fins to aid swimming etc. etc. Crystal clear again.
DAVID: Immediate driving forces are part of the pattern of survival for the overall purpose of evolution to the goal, humans. Crystal clear.
So you agree that the driving force for your God’s design of fins, camouflage and patterns of migration was survival, but God’s one and only purpose in designing all of these was to enable them to eat and be eaten (to survive or not to survive) until he could design humans, which apparently means that survival is a driving force but is not a driving force.
Human evolution; "Little foot's" balance mechanism
by David Turell , Saturday, February 02, 2019, 18:47 (2119 days ago) @ dhw
dhw: Yes, if your God exists he is the driving force behind life and evolution. But why do you refuse to acknowledge that the purpose behind a design is also a driving force?
DAVID: Because I view God as the driver, and survival a secondary requirement since evolving organisms must survive for each advance to occur. Again a difference in nuance.
DAVID (re skin colour): These studies certainly appear to explain why our species adapted light or dark skin. Since folate is so important to reproduction, I would suspect it was more of a driving force than Vitamin D in producing this adaptation. (dhw’s bold)
dhw: And so the requirement for folate to aid reproduction was a “driving force”. Just like the requirement for fins to aid swimming etc. etc. Crystal clear again.
DAVID: Immediate driving forces are part of the pattern of survival for the overall purpose of evolution to the goal, humans. Crystal clear.
dhw: So you agree that the driving force for your God’s design of fins, camouflage and patterns of migration was survival, but God’s one and only purpose in designing all of these was to enable them to eat and be eaten (to survive or not to survive) until he could design humans, which apparently means that survival is a driving force but is not a driving force.
Quibbling again. Survival is a secondary requirement for evolution to continue to its goal
Human evolution; "Little foot's" balance mechanism
DAVID (re skin colour): These studies certainly appear to explain why our species adapted light or dark skin. Since folate is so important to reproduction, I would suspect it was more of a driving force than Vitamin D in producing this adaptation. (dhw’s bold)
dhw: And so the requirement for folate to aid reproduction was a “driving force”. Just like the requirement for fins to aid swimming etc. etc. Crystal clear again.
DAVID: Immediate driving forces are part of the pattern of survival for the overall purpose of evolution to the goal, humans. Crystal clear.
dhw: So you agree that the driving force for your God’s design of fins, camouflage and patterns of migration was survival, but God’s one and only purpose in designing all of these was to enable them to eat and be eaten (to survive or not to survive) until he could design humans, which apparently means that survival is a driving force but is not a driving force.
DAVID: Quibbling again. Survival is a secondary requirement for evolution to continue to its goal.
Sorry, but the quibble is entirely yours. If organisms don’t survive, there is no evolution, and an immediate driving force is a driving force.
Human evolution; "Little foot's" balance mechanism
by David Turell , Sunday, February 03, 2019, 14:50 (2118 days ago) @ dhw
DAVID (re skin colour): These studies certainly appear to explain why our species adapted light or dark skin. Since folate is so important to reproduction, I would suspect it was more of a driving force than Vitamin D in producing this adaptation. (dhw’s bold)
dhw: And so the requirement for folate to aid reproduction was a “driving force”. Just like the requirement for fins to aid swimming etc. etc. Crystal clear again.
DAVID: Immediate driving forces are part of the pattern of survival for the overall purpose of evolution to the goal, humans. Crystal clear.
dhw: So you agree that the driving force for your God’s design of fins, camouflage and patterns of migration was survival, but God’s one and only purpose in designing all of these was to enable them to eat and be eaten (to survive or not to survive) until he could design humans, which apparently means that survival is a driving force but is not a driving force.
DAVID: Quibbling again. Survival is a secondary requirement for evolution to continue to its goal.
dhw: Sorry, but the quibble is entirely yours. If organisms don’t survive, there is no evolution, and an immediate driving force is a driving force.
I will continue to view survival as a requirement of design driven evolution.
Human evolution; "Little foot's" balance mechanism
DAVID (re skin colour): These studies certainly appear to explain why our species adapted light or dark skin. Since folate is so important to reproduction, I would suspect it was more of a driving force than Vitamin D in producing this adaptation. (dhw’s bold)
dhw: And so the requirement for folate to aid reproduction was a “driving force”. Just like the requirement for fins to aid swimming etc. etc. Crystal clear again.
DAVID: Immediate driving forces are part of the pattern of survival for the overall purpose of evolution to the goal, humans. Crystal clear.
dhw: So you agree that the driving force for your God’s design of fins, camouflage and patterns of migration was survival, but God’s one and only purpose in designing all of these was to enable them to eat and be eaten (to survive or not to survive) until he could design humans, which apparently means that survival is a driving force but is not a driving force.
DAVID: Quibbling again. Survival is a secondary requirement for evolution to continue to its goal.
dhw: Sorry, but the quibble is entirely yours. If organisms don’t survive, there is no evolution, and an immediate driving force is a driving force.
DAVID: I will continue to view survival as a requirement of design driven evolution.
Of course. You can’t have evolution without survival. I’m afraid that does not mean an immediate driving force is not a driving force. Why don’t we leave it at that?
Human evolution; "Little foot's" balance mechanism
by David Turell , Monday, February 04, 2019, 15:22 (2117 days ago) @ dhw
DAVID (re skin colour): These studies certainly appear to explain why our species adapted light or dark skin. Since folate is so important to reproduction, I would suspect it was more of a driving force than Vitamin D in producing this adaptation. (dhw’s bold)
dhw: And so the requirement for folate to aid reproduction was a “driving force”. Just like the requirement for fins to aid swimming etc. etc. Crystal clear again.
DAVID: Immediate driving forces are part of the pattern of survival for the overall purpose of evolution to the goal, humans. Crystal clear.
dhw: So you agree that the driving force for your God’s design of fins, camouflage and patterns of migration was survival, but God’s one and only purpose in designing all of these was to enable them to eat and be eaten (to survive or not to survive) until he could design humans, which apparently means that survival is a driving force but is not a driving force.
DAVID: Quibbling again. Survival is a secondary requirement for evolution to continue to its goal.
dhw: Sorry, but the quibble is entirely yours. If organisms don’t survive, there is no evolution, and an immediate driving force is a driving force.
DAVID: I will continue to view survival as a requirement of design driven evolution.
dhw: Of course. You can’t have evolution without survival. I’m afraid that does not mean an immediate driving force is not a driving force. Why don’t we leave it at that?
Fine. you still don't accept a designer.
Human evolution; "Little foot's" balance mechanism
DAVID: Immediate driving forces are part of the pattern of survival for the overall purpose of evolution to the goal, humans. Crystal clear.
dhw: So you agree that the driving force for your God’s design of fins, camouflage and patterns of migration was survival, but God’s one and only purpose in designing all of these was to enable them to eat and be eaten (to survive or not to survive) until he could design humans, which apparently means that survival is a driving force but is not a driving force.
DAVID: Quibbling again. Survival is a secondary requirement for evolution to continue to its goal.
dhw: Sorry, but the quibble is entirely yours. If organisms don’t survive, there is no evolution, and an immediate driving force is a driving force.
DAVID: I will continue to view survival as a requirement of design driven evolution.
dhw: Of course. You can’t have evolution without survival. I’m afraid that does not mean an immediate driving force is not a driving force. Why don’t we leave it at that?
DAVID: Fine. you still don't accept a designer.
I will keep your agreement for future reference, in case you bring up “survival” again as an issue. My agnostic non-acceptance/non-rejection of a designer is irrelevant.
Human evolution; "Little foot's" balance mechanism
by David Turell , Tuesday, February 05, 2019, 15:26 (2116 days ago) @ dhw
DAVID: Immediate driving forces are part of the pattern of survival for the overall purpose of evolution to the goal, humans. Crystal clear.
dhw: So you agree that the driving force for your God’s design of fins, camouflage and patterns of migration was survival, but God’s one and only purpose in designing all of these was to enable them to eat and be eaten (to survive or not to survive) until he could design humans, which apparently means that survival is a driving force but is not a driving force.
DAVID: Quibbling again. Survival is a secondary requirement for evolution to continue to its goal.
dhw: Sorry, but the quibble is entirely yours. If organisms don’t survive, there is no evolution, and an immediate driving force is a driving force.
DAVID: I will continue to view survival as a requirement of design driven evolution.
dhw: Of course. You can’t have evolution without survival. I’m afraid that does not mean an immediate driving force is not a driving force. Why don’t we leave it at that?
DAVID: Fine. you still don't accept a designer.
I will keep your agreement for future reference, in case you bring up “survival” again as an issue. My agnostic non-acceptance/non-rejection of a designer is irrelevant.
Yes, we will agree to disagree into the future.
Human evolution; Arthropithicus walking on ground
by David Turell , Tuesday, April 30, 2019, 16:06 (2032 days ago) @ David Turell
Ardipithicus is a million years older than Lucy and has a monkey-like foot:
https://phys.org/news/2019-04-human-ancestors-grounded-analysis.html
"'Our unique form of human locomotion evolved from an ancestor that moved in similar ways to the living African apes—chimpanzees, bonobos, and gorillas," explains Thomas Prang, a doctoral candidate in New York University's Department of Anthropology and the author of the study, which appears in the journal eLife. "In other words, the common ancestor we share with chimpanzees and bonobos was an African ape that probably had adaptations to living on the ground in some form and frequency."
"The way that humans walk—striding bipedalism—is unique among all living mammals, an attribute resulting from myriad changes over time.
"'The human body has been dramatically modified by evolutionary processes over the last several million years in ways that happened to make us better walkers and runners," notes Prang.
Much of this change is evident in the human foot, which has evolved to be a propulsive organ, with a big toe incapable of ape-like grasping and a spring-like, energy-saving arch that runs from front to back.
***
" Prang, a researcher in NYU's Center for the Study of Human Origins, focused on the fossil species Ardipithecus ramidus ('Ardi'), a 4.4 million-years-old human ancestor from Ethiopia—more than a million years older than the well-known 'Lucy' fossil. Ardi's bones were first publicly revealed in 2009 and have been the subject of debate since then.
"In his research, Prang ascertained the relative length proportions of multiple bones in the primate foot skeleton to evaluate the relationship between species' movement (locomotion) and their skeletal characteristics (morphology). In addition, drawing upon the Ardi fossils, he used statistical methods to reconstruct or estimate what the common ancestor of humans and chimpanzees might have looked like.
"Here, he found that the African apes show a clear signal of being adapted to ground-living. The results also reveal that the Ardi foot and the estimated morphology of the human-chimpanzee last common ancestor is most similar to these African ape species.
"'Therefore, humans evolved from an ancestor that had adaptations to living on the ground, perhaps not unlike those found in African apes," Prang concludes. "These findings suggest that human bipedalism was derived from a form of locomotion similar to that of living African apes, which contrasts with the original interpretation of these fossils."
"The original interpretation of the Ardi foot fossils, published in 2009, suggested that its foot was more monkey-like than chimpanzee- or gorilla-like. The implication of this interpretation is that many of the features shared by living great apes (chimpanzees, bonobos, gorillas, and orangutans) in their foot and elsewhere must have evolved independently in each lineage—in a different time and place.
"'Humans are part of the natural world and our locomotor adaptation—bipedalism—cannot be understood outside of its natural evolutionary context," Prang observes. "Large-scale evolutionary changes do not seem to happen spontaneously. Instead, they are rooted in deeper histories revealed by the study of the fossil record." (my bold)
Comment: This shows how uniquely different we are. we came from apes but we are not apes. My bold above is to show this is a Darwin interpretation
Human evolution; Arthropithicus walking on ground
QUOTES: "The way that humans walk—striding bipedalism—is unique among all living mammals, an attribute resulting from myriad changes over time."
"'The human body has been dramatically modified by evolutionary processes over the last several million years in ways that happened to make us better walkers and runners," notes Prang.
"'Humans are part of the natural world and our locomotor adaptation—bipedalism—cannot be understood outside of its natural evolutionary context," Prang observes. "Large-scale evolutionary changes do not seem to happen spontaneously. Instead, they are rooted in deeper histories revealed by the study of the fossil record." (David’s bold)
DAVID: This shows how uniquely different we are. we came from apes but we are not apes. My bold above is to show this is a Darwin interpretation.
Yes, it is a Darwin interpretation, and since it is based on the fossil record – which you do not dispute – it is clear evidence that in this particular case, Darwin was right. You seem to think that the very mention of his name invalidates any research that supports him. You are then left with no idea why your God, whose sole purpose was to create H. sapiens, should have chosen to use such an itty-bitty method, when according to you he knows exactly what he wants and has the power to get it through a dabble (think of your favourite pre-whale having its legs turned into flippers before it enters the water). However, with the Cambrian in mind, I agree that the claim you have bolded is far too general.
Human evolution; Arthropithicus walking on ground
by David Turell , Wednesday, May 01, 2019, 20:01 (2031 days ago) @ dhw
QUOTES: "The way that humans walk—striding bipedalism—is unique among all living mammals, an attribute resulting from myriad changes over time."
"'The human body has been dramatically modified by evolutionary processes over the last several million years in ways that happened to make us better walkers and runners," notes Prang.
"'Humans are part of the natural world and our locomotor adaptation—bipedalism—cannot be understood outside of its natural evolutionary context," Prang observes. "Large-scale evolutionary changes do not seem to happen spontaneously. Instead, they are rooted in deeper histories revealed by the study of the fossil record." (David’s bold)
DAVID: This shows how uniquely different we are. we came from apes but we are not apes. My bold above is to show this is a Darwin interpretation.
dhw: Yes, it is a Darwin interpretation, and since it is based on the fossil record – which you do not dispute – it is clear evidence that in this particular case, Darwin was right. You seem to think that the very mention of his name invalidates any research that supports him. You are then left with no idea why your God, whose sole purpose was to create H. sapiens, should have chosen to use such an itty-bitty method, when according to you he knows exactly what he wants and has the power to get it through a dabble (think of your favourite pre-whale having its legs turned into flippers before it enters the water). However, with the Cambrian in mind, I agree that the claim you have bolded is far too general.
My point is the author's 'deeper histories' may simply be viewed as God in action. That
certainly fits the Cambrian Gap you have noted..
Human evolution; Arthropithicus walking on ground
QUOTE: "'Humans are part of the natural world and our locomotor adaptation—bipedalism—cannot be understood outside of its natural evolutionary context," Prang observes. "Large-scale evolutionary changes do not seem to happen spontaneously. Instead, they are rooted in deeper histories revealed by the study of the fossil record." (David’s bold)
DAVID: This shows how uniquely different we are. we came from apes but we are not apes. My bold above is to show this is a Darwin interpretation.
dhw: Yes, it is a Darwin interpretation, and since it is based on the fossil record – which you do not dispute – it is clear evidence that in this particular case, Darwin was right. You seem to think that the very mention of his name invalidates any research that supports him. You are then left with no idea why your God, whose sole purpose was to create H. sapiens, should have chosen to use such an itty-bitty method, when according to you he knows exactly what he wants and has the power to get it through a dabble (think of your favourite pre-whale having its legs turned into flippers before it enters the water). However, with the Cambrian in mind, I agree that the claim you have bolded is far too general.
DAVID: My point is the author's 'deeper histories' may simply be viewed as God in action. That certainly fits the Cambrian Gap you have noted.
It is a prime example of itty-bitty evolution, proven by the fossil record, though we have always agreed that Darwin was wrong to claim that “Natura non facit saltum”. I’m glad you now accept that Darwin’s itty-bitty theory is at least partly true, and of course you are still left with the problem of how to reconcile this with your own anthropocentric interpretation of evolution as summarized above.
Human evolution; Arthropithicus walking on ground
by David Turell , Thursday, May 02, 2019, 15:17 (2030 days ago) @ dhw
QUOTE: "'Humans are part of the natural world and our locomotor adaptation—bipedalism—cannot be understood outside of its natural evolutionary context," Prang observes. "Large-scale evolutionary changes do not seem to happen spontaneously. Instead, they are rooted in deeper histories revealed by the study of the fossil record." (David’s bold)
DAVID: This shows how uniquely different we are. we came from apes but we are not apes. My bold above is to show this is a Darwin interpretation.
dhw: Yes, it is a Darwin interpretation, and since it is based on the fossil record – which you do not dispute – it is clear evidence that in this particular case, Darwin was right. You seem to think that the very mention of his name invalidates any research that supports him. You are then left with no idea why your God, whose sole purpose was to create H. sapiens, should have chosen to use such an itty-bitty method, when according to you he knows exactly what he wants and has the power to get it through a dabble (think of your favourite pre-whale having its legs turned into flippers before it enters the water). However, with the Cambrian in mind, I agree that the claim you have bolded is far too general.
DAVID: My point is the author's 'deeper histories' may simply be viewed as God in action. That certainly fits the Cambrian Gap you have noted.
dhw: It is a prime example of itty-bitty evolution, proven by the fossil record, though we have always agreed that Darwin was wrong to claim that “Natura non facit saltum”. I’m glad you now accept that Darwin’s itty-bitty theory is at least partly true, and of course you are still left with the problem of how to reconcile this with your own anthropocentric interpretation of evolution as summarized above.
I view nothing about the Athropithicus developments as itty-bitty. The quote above specifically states "large scale evolutionary changes' come from past history. You see iity -bitty, I don't.
Human evolution; Arthropithicus walking on ground
dhw: It is a prime example of itty-bitty evolution, proven proven by the fossil record, though we have always agreed that Darwin was wrong to claim that “Natura non facit saltum”. I’m glad you now accept that Darwin’s itty-bitty theory is at least partly true, and of course you are still left with the problem of how to reconcile this with your own anthropocentric interpretation of evolution as summarized above.
DAVID: I view nothing about the Athropithicus developments as itty-bitty. The quote above specifically states "large scale evolutionary changes' come from past history. You see iity -bitty, I don't.
QUOTES: "The way that humans walk—striding bipedalism—is unique among all living mammals, an attribute resulting from myriad changes over time. (dhw’s bold)
"'The human body has been dramatically modified by evolutionary processes over the last several million years in ways that happened to make us better walkers and runners," notes Prang. (dhw’s bold)
If the fossil record shows that bipedalism and the human body reached their final form as a result of myriad changes and dramatic modifications, how can you honestly claim that this is not an itty-bitty process?
Human evolution; Arthropithicus walking on ground
by David Turell , Friday, May 03, 2019, 19:22 (2029 days ago) @ dhw
dhw: It is a prime example of itty-bitty evolution, proven proven by the fossil record, though we have always agreed that Darwin was wrong to claim that “Natura non facit saltum”. I’m glad you now accept that Darwin’s itty-bitty theory is at least partly true, and of course you are still left with the problem of how to reconcile this with your own anthropocentric interpretation of evolution as summarized above.
DAVID: I view nothing about the Athropithicus developments as itty-bitty. The quote above specifically states "large scale evolutionary changes' come from past history. You see iity -bitty, I don't.
QUOTES: "The way that humans walk—striding bipedalism—is unique among all living mammals, an attribute resulting from myriad changes over time. (dhw’s bold)
"'The human body has been dramatically modified by evolutionary processes over the last several million years in ways that happened to make us better walkers and runners," notes Prang. (dhw’s bold)
dhw: If the fossil record shows that bipedalism and the human body reached their final form as a result of myriad changes and dramatic modifications, how can you honestly claim that this is not an itty-bitty process?
Have you forgotten, from the fossils we have the brain size jumped 200cc each time it enlarged, which then involves birth canal problems as well as skull enlargements. Not tiny steps at any point.
Human evolution; Arthropithicus walking on ground
dhw: It is a prime example of itty-bitty evolution, proven proven by the fossil record, though we have always agreed that Darwin was wrong to claim that “Natura non facit saltum”. I’m glad you now accept that Darwin’s itty-bitty theory is at least partly true, and of course you are still left with the problem of how to reconcile this with your own anthropocentric interpretation of evolution as summarized above.
DAVID: I view nothing about the Athropithicus developments as itty-bitty. The quote above specifically states "large scale evolutionary changes' come from past history. You see iity -bitty, I don't.
QUOTES: "The way that humans walk—striding bipedalism—is unique among all living mammals, an attribute resulting from myriad changes over time. (dhw’s bold)
"'The human body has been dramatically modified by evolutionary processes over the last several million years in ways that happened to make us better walkers and runners," notes Prang. (dhw’s bold)
dhw: If the fossil record shows that bipedalism and the human body reached their final form as a result of myriad changes and dramatic modifications, how can you honestly claim that this is not an itty-bitty process?
DAVID: Have you forgotten, from the fossils we have the brain size jumped 200cc each time it enlarged, which then involves birth canal problems as well as skull enlargements. Not tiny steps at any point.
Some steps are small (why do you suddenly ignore the history of bipedalism?) and some are large, but they are all itty-bitty if you believe that your always-in-control God’s sole purpose was to produce H. sapiens. Do you really think that a larger brain or a different shaped/sized birth canal is an innovation? Why bother with these “myriad” interim stages of brain, pelvis, big toe etc.? And why bother with the complexities of the whale if all he wanted was humans? The answer is that in both cases you have no idea, but you insist that this was his chosen method of designing the only thing he wanted to design.
Human evolution; Arthropithicus walking on ground
by David Turell , Saturday, May 04, 2019, 19:06 (2028 days ago) @ dhw
dhw: It is a prime example of itty-bitty evolution, proven proven by the fossil record, though we have always agreed that Darwin was wrong to claim that “Natura non facit saltum”. I’m glad you now accept that Darwin’s itty-bitty theory is at least partly true, and of course you are still left with the problem of how to reconcile this with your own anthropocentric interpretation of evolution as summarized above.
DAVID: I view nothing about the Athropithicus developments as itty-bitty. The quote above specifically states "large scale evolutionary changes' come from past history. You see iity -bitty, I don't.
QUOTES: "The way that humans walk—striding bipedalism—is unique among all living mammals, an attribute resulting from myriad changes over time. (dhw’s bold)
"'The human body has been dramatically modified by evolutionary processes over the last several million years in ways that happened to make us better walkers and runners," notes Prang. (dhw’s bold)dhw: If the fossil record shows that bipedalism and the human body reached their final form as a result of myriad changes and dramatic modifications, how can you honestly claim that this is not an itty-bitty process?
DAVID: Have you forgotten, from the fossils we have the brain size jumped 200cc each time it enlarged, which then involves birth canal problems as well as skull enlargements. Not tiny steps at any point.
dhw: Some steps are small (why do you suddenly ignore the history of bipedalism?) and some are large, but they are all itty-bitty if you believe that your always-in-control God’s sole purpose was to produce H. sapiens. Do you really think that a larger brain or a different shaped/sized birth canal is an innovation? Why bother with these “myriad” interim stages of brain, pelvis, big toe etc.? And why bother with the complexities of the whale if all he wanted was humans? The answer is that in both cases you have no idea, but you insist that this was his chosen method of designing the only thing he wanted to design.
Evolution requires steps to reach a goal. No matter how hard you try to make the steps as small, the design requirements and the gaps in forms is very large. Each step in whale evolution is the result of highly complex phenotypical and physiological design steps. In my view as God chose evolution to reach His goal of large-brained humans He knew He had to provide a larger bush of eco-niches to feel everyone on the way over lots of time. I don't know why you cannot see that as totally logical?
Human evolution; Arthropithicus walking on ground
by David Turell , Wednesday, June 14, 2023, 15:56 (526 days ago) @ David Turell
Latest study on theoretical muscles:
https://www.livescience.com/archaeology/32-million-year-old-human-ancestor-lucy-had-mas...
"Our 3.2 million-year-old ancestor "Lucy" could stand and walk upright just like modern humans do, new 3D muscle modeling reveals.
"The finding bolsters a growing consensus among researchers that Australopithecus afarensis — the extinct species to which Lucy belongs — walked erect rather than with a chimpanzee-like, crouching waddle.
"The hominin's reconstructed pelvis and leg muscles also suggest that she could climb trees, meaning the species likely thrived in both forest and grassland habitats in East Africa 3 million to 4 million years ago.
"'Lucy's muscles suggest that she was as proficient at bipedalism as we are, while possibly also being at home in the trees," Ashleigh Wiseman, a research associate at the University of Cambridge's McDonald Institute for Archaeological Research in the U.K. who conducted the modeling study, said in a statement. "She would have been able to exploit both habitats effectively."
"Lucy's fossils are the best-preserved Australopithecus remains ever unearthed, with 40% of her skeleton recovered from Ethiopia's Hadar region in the mid-1970s. Her bones indicate that she stood 3.4 feet (1 meter) tall and weighed between 29 and 93 pounds (13 to 42 kilograms). Her discovery pointed to the possibility that human ancestors could walk upright long before they evolved bigger brains.
"The reconstruction shows that Lucy could straighten her knee joints and extend her hips in a similar way to modern humans, suggesting that the species could stand and walk upright.
"The model also reveals the proportions of fat and muscle in Lucy's legs, showing they were far more muscular than a modern human's and similar in composition to a bonobo's (Pan paniscus). While a human thigh is about 50% muscle, Lucy's were likely 74% and less fatty. Some of her calf and thigh muscles occupied twice as much space in her legs as they do in human legs today.
"Lucy's knees demonstrated a wider range of motion in the extension-flexion axis than a human's. This, combined with her muscle mass, suggests that A. afarensis could utilize a wide range of habitats, from dense forests to grassy savannas. This type of locomotion is not seen in any modern animal, Wiseman said. "Lucy likely walked and moved in a way that we do not see in any living species today."
***
"However, reconstructing the muscles is a novel and exciting method to confirm bipedalism, Spoor told Live Science in an email. "This approach is certainly promising," he said. "It goes beyond the sometimes somewhat simplistic interpretations of paleontologists when it comes to inferring what movements and locomotor pattern characterized an extinct species."
"Muscle modeling has already helped researchers gauge the walking speed of a Tyrannosaurus rex and could shed light on similar traits in archaic humans. "By applying similar techniques to ancestral humans, we want to reveal the spectrum of physical movement that propelled our evolution," Wiseman said. "
Comment: this new technique gives us a broader picture of what Lucy must have been like.
Human evolution; our complex speech mechanism
dhw: According to you, your God caused the BB, and so he existed before the BB. Before, now and after are one concept of time. Nobody can possibly prove anything about what happened before the BB (if it happened). I agree that one cause is simpler than two causes. The one cause may be an eternal and infinite universe of energy and matter constantly changing itself. No, I don’t believe it, and I don’t disbelieve it, just as I don’t believe or disbelieve in a single, conscious, sourceless, eternal mind. Maybe the complex evolutionary process was created (top down), or maybe it evolved (bottom up).
DAVID: All I presented has appeared here before. If bottom up, from what, and what pushed it to evolve?
dhw: Yes, we have discussed it many times. Bottom up from eternally changing combinations of materials. But I can't tell you how they might have acquired the basic consciousness to form life, any more than you can tell me how a sourceless, universal, conscious mind can simply have been there for ever. Two first cause hypotheses that are as inexplicable as each other. Enough to make a thinker embrace agnosticism!
DAVID: Not if one tries to explain the complex designs in living forms.
dhw: I accept that as a good reason for your faith – but you have always acknowledged that it requires faith and not reason to accept one mystery as the answer to another.
DAVID: Reasoning about the need for a designer is strong enough to lead to faith. In my mind there must be a designer. The complex living biology I see and understand with my medical training requires that conclusion. You and I have different backgrounds, which may explain our different positions.
It has nothing whatsoever to do with background – unless you now wish to claim that every doctor, biologist, biochemist etc. shares your faith. I don’t know how often I have to repeat that I accept the design argument as good reason for faith, and it is one of two major influences (along with psychic experiences) that leave me open to the possibility of a God. But in all these discussions you simply refuse to acknowledge the reason why I myself cannot take that leap of faith, as bolded above.
Human evolution; our complex speech mechanism
by David Turell , Friday, December 07, 2018, 21:14 (2176 days ago) @ dhw
dhw: According to you, your God caused the BB, and so he existed before the BB. Before, now and after are one concept of time. Nobody can possibly prove anything about what happened before the BB (if it happened). I agree that one cause is simpler than two causes. The one cause may be an eternal and infinite universe of energy and matter constantly changing itself. No, I don’t believe it, and I don’t disbelieve it, just as I don’t believe or disbelieve in a single, conscious, sourceless, eternal mind. Maybe the complex evolutionary process was created (top down), or maybe it evolved (bottom up).
DAVID: All I presented has appeared here before. If bottom up, from what, and what pushed it to evolve?
dhw: Yes, we have discussed it many times. Bottom up from eternally changing combinations of materials. But I can't tell you how they might have acquired the basic consciousness to form life, any more than you can tell me how a sourceless, universal, conscious mind can simply have been there for ever. Two first cause hypotheses that are as inexplicable as each other. Enough to make a thinker embrace agnosticism!
DAVID: Not if one tries to explain the complex designs in living forms.
dhw: I accept that as a good reason for your faith – but you have always acknowledged that it requires faith and not reason to accept one mystery as the answer to another.
DAVID: Reasoning about the need for a designer is strong enough to lead to faith. In my mind there must be a designer. The complex living biology I see and understand with my medical training requires that conclusion. You and I have different backgrounds, which may explain our different positions.
dhw: It has nothing whatsoever to do with background – unless you now wish to claim that every doctor, biologist, biochemist etc. shares your faith. I don’t know how often I have to repeat that I accept the design argument as good reason for faith, and it is one of two major influences (along with psychic experiences) that leave me open to the possibility of a God. But in all these discussions you simply refuse to acknowledge the reason why I myself cannot take that leap of faith, as bolded above.
A survey, a number of years ago, found 40% of physicians are believers. I acknowledge your problem.
Human evolution; our complex speech mechanism
DAVID: Reasoning about the need for a designer is strong enough to lead to faith. In my mind there must be a designer. The complex living biology I see and understand with my medical training requires that conclusion. You and I have different backgrounds, which may explain our different positions.
dhw: It has nothing whatsoever to do with background – unless you now wish to claim that every doctor, biologist, biochemist etc. shares your faith. I don’t know how often I have to repeat that I accept the design argument as good reason for faith, and it is one of two major influences (along with psychic experiences) that leave me open to the possibility of a God. But in all these discussions you simply refuse to acknowledge the reason why I myself cannot take that leap of faith. [...]
DAVID: A survey, a number of years ago, found 40% of physicians are believers. I acknowledge your problem.
Thank you. I wonder how many of the remaining 60% are atheists and how many are agnostics.
Human evolution; our complex speech mechanism
by David Turell , Saturday, December 08, 2018, 22:14 (2175 days ago) @ dhw
DAVID: Reasoning about the need for a designer is strong enough to lead to faith. In my mind there must be a designer. The complex living biology I see and understand with my medical training requires that conclusion. You and I have different backgrounds, which may explain our different positions.
dhw: It has nothing whatsoever to do with background – unless you now wish to claim that every doctor, biologist, biochemist etc. shares your faith. I don’t know how often I have to repeat that I accept the design argument as good reason for faith, and it is one of two major influences (along with psychic experiences) that leave me open to the possibility of a God. But in all these discussions you simply refuse to acknowledge the reason why I myself cannot take that leap of faith. [...]
DAVID: A survey, a number of years ago, found 40% of physicians are believers. I acknowledge your problem.
dhw: Thank you. I wonder how many of the remaining 60% are atheists and how many are agnostics.
Have no idea
Human evolution; a gene for primate brains
by David Turell , Sunday, December 09, 2018, 00:32 (2174 days ago) @ David Turell
Found in a new study. Our brains are different than other mammals:
https://www.sciencedaily.com/releases/2018/12/181206120047.htm
"University of Otago researchers have discovered information about a gene that sets primates -- great apes and humans -- apart from other mammals, through the study of a rare developmental brain disorder.
"Dr Adam O'Neill carried out the research as part of his PhD at the University of Otago, under the supervision of Professor Stephen Robertson, discovering that the PLEKHG6 gene has qualities that drives aspects of brain development differently in primates compared to other species.
"'Broadly speaking, this gene can be thought of as one of the genetic factors that make us human in a neurological sense,"...
***
"Their results showed that the particular genetic change that disabled a component of this gene (PLEKHG6) altered its ability to support the growth and proliferation of specialised stem cells in the developing brain. In addition, some of these cells also failed to migrate to their correct position in the growing "mini-brain" during the first few weeks of brain development.
"Professor Robertson says it has been known for a while that these stem cells behave differently between primates/humans and other animals, but understanding what genes regulate these differences has been a mystery.
"Adam's achievement has been to show that this particular component of the PLEKHG6 gene is one such regulator that humans have 'acquired' very recently in their evolution to make their brains 'exceptional'."
"Dr O'Neill says there are very few genetic elements that are primate specific in our genome, so this discovery adds to a very short list of genetic factors that, at least in one sense, make us human."
Comment: A lucky chance break? If that is the case all of the preparatory steps to reach the point where primates could appear are lucky contingencies. Doubtful.
Human evolution; a gene for primate brains
by David Turell , Tuesday, December 11, 2018, 17:52 (2172 days ago) @ David Turell
Found in a new study. Our brains are different than other mammals:
https://www.sciencedaily.com/releases/2018/12/181206120047.htm
"University of Otago researchers have discovered information about a gene that sets primates -- great apes and humans -- apart from other mammals, through the study of a rare developmental brain disorder.
"Dr Adam O'Neill carried out the research as part of his PhD at the University of Otago, under the supervision of Professor Stephen Robertson, discovering that the PLEKHG6 gene has qualities that drives aspects of brain development differently in primates compared to other species.
"'Broadly speaking, this gene can be thought of as one of the genetic factors that make us human in a neurological sense,"...
***
"Their results showed that the particular genetic change that disabled a component of this gene (PLEKHG6) altered its ability to support the growth and proliferation of specialised stem cells in the developing brain. In addition, some of these cells also failed to migrate to their correct position in the growing "mini-brain" during the first few weeks of brain development.
"Professor Robertson says it has been known for a while that these stem cells behave differently between primates/humans and other animals, but understanding what genes regulate these differences has been a mystery.
"Adam's achievement has been to show that this particular component of the PLEKHG6 gene is one such regulator that humans have 'acquired' very recently in their evolution to make their brains 'exceptional'."
"Dr O'Neill says there are very few genetic elements that are primate specific in our genome, so this discovery adds to a very short list of genetic factors that, at least in one sense, make us human."
Comment: A lucky chance break? If that is the case all of the preparatory steps to reach the point where primates could appear are lucky contingencies. Doubtful.
The original paper summary:
The mammalian neocortex has undergone remarkable changes through evolution. A consequence of
such rapid evolutionary events could be a trade-off that has rendered the brain susceptible to certain neurodevelopmental and neuropsychiatric conditions. We analyzed the exomes of 65 patients with the structural brain malformation periventricular nodular heterotopia (PH). De novo coding variants were observed in excess in genes defining a transcriptomic signature of basal radial glia, a cell type linked to brain evolution. In addition, we located two variants in human isoforms of two genes that have no ortholog in mice. Modulating the levels of one of these isoforms for the gene PLEKHG6 demonstrated its role in regulating neuroprogenitor differentiation and neuronal migration via RhoA, with phenotypic recapitulation of PH in human cerebral organoids. This suggests that this PLEKHG6 isoform is an example of a primate-specific genomic element supporting brain development.
https://www.cell.com/cell-reports/pdf/S2211-1247(18)31775-3.pdf
Human evolution; theory of hominin language
by David Turell , Thursday, December 13, 2018, 14:37 (2170 days ago) @ David Turell
This much seems well established but how actual language started is still problematic:
http://blogs.discovermagazine.com/crux/2018/12/07/where-does-language-come-from/#.XBJqq...
"There are at least three elements of language only present in hominins:
First, is a fine-control over our vocal tracts. Other apes are likely born with a more limited repertoire of vocalizations. The difference comes down to how our brains are wired: Humans have direct connections between the neurons controlling our voice box and the motor cortex, the region of our brain responsible for voluntary movements. Brain scans show these connections are lacking in other primates. (my bold)
"Next is our tendency to communicate for the sake of communicating. To encapsulate this, biologist Fitch used the German word Mitteilungsbedürfnis, “the drive to share thoughts.” Whereas chimps use a finite set of calls and gestures to convey the essentials — food, sex and danger — humans talk to bond and exchange ideas, and strive to ensure we’re understood. Most researchers attribute this difference to an idea called “theory of mind,” the understanding that others have thoughts. Chimps demonstrate more limited theory of mind, whereas humans know that other humans think things — and we’re constantly using language to uncover and influence those thoughts.
"The last difference is hierarchical syntax. Phrases and sentences have nested structure and these provide meaning beyond the simple sequence of words. For instance, take the sentence: “Chad, who was out to lunch with Tony, was late to the meeting.” Hierarchical syntax processing allows us to correctly interpret that Chad was late to the meeting, even though “Tony” is closer to the verb “was late.” Over 60 years ago and still today, linguist Noam Chomsky proposed hierarchical syntax as the key to language.
"So hypotheses for language origins must explain (at least) these three traits: precise vocal learning and control, overtly social communication and hierarchical syntax."
Comment: Note my bold. We are physically wired differently. This describes the basics, beyond this is pure unestablished sets of theories. We are different in kind.
Human evolution; theory of hominin language
"There are at least three elements of language only present in hominins:
First, is a fine-control over our vocal tracts. Other apes are likely born with a more limited repertoire of vocalizations. The difference comes down to how our brains are wired: Humans have direct connections between the neurons controlling our voice box and the motor cortex, the region of our brain responsible for voluntary movements. Brain scans show these connections are lacking in other primates. (David's bold)
DAVID: Note my bold. We are physically wired differently. This describes the basics, beyond this is pure unestablished sets of theories. We are different in kind.
I really don’t think there are many people who would say that we are exactly the same as our fellow primates, and I doubt if many people would say that elephants are the same “kind” as whales or ants or the duckbilled platypus. Yes, we are different, and our language is a million times more complicated than that of our fellow animals, and we are self-aware and very clever. But that still doesn’t mean that your God’s sole purpose from the very start was to create us, and that elephants, whales, ants and the duckbilled platypus were specially designed simply to provide food until he could specially design us.
Human evolution; theory of hominin language
by David Turell , Friday, December 14, 2018, 15:26 (2169 days ago) @ dhw
"There are at least three elements of language only present in hominins:
First, is a fine-control over our vocal tracts. Other apes are likely born with a more limited repertoire of vocalizations. The difference comes down to how our brains are wired: Humans have direct connections between the neurons controlling our voice box and the motor cortex, the region of our brain responsible for voluntary movements. Brain scans show these connections are lacking in other primates. (David's bold)DAVID: Note my bold. We are physically wired differently. This describes the basics, beyond this is pure unestablished sets of theories. We are different in kind.
dhw: I really don’t think there are many people who would say that we are exactly the same as our fellow primates, and I doubt if many people would say that elephants are the same “kind” as whales or ants or the duckbilled platypus. Yes, we are different, and our language is a million times more complicated than that of our fellow animals, and we are self-aware and very clever. But that still doesn’t mean that your God’s sole purpose from the very start was to create us, and that elephants, whales, ants and the duckbilled platypus were specially designed simply to provide food until he could specially design us.
Ah, it seems you have forgotten that 'different in kind' refers to the other primates we left behind and also Adler's theory which supports our assent to the top pf the heap. All the animals you listed are obviously foodstuff, and not on the point of my comment, Another of your inventive neatly formed sidesteps.
Human evolution; theory of hominin language
QUOTE: "There are at least three elements of language only present in hominins:
First, is a fine-control over our vocal tracts. Other apes are likely born with a more limited repertoire of vocalizations. The difference comes down to how our brains are wired: Humans have direct connections between the neurons controlling our voice box and the motor cortex, the region of our brain responsible for voluntary movements. Brain scans show these connections are lacking in other primates. (David's bold)
DAVID: Note my bold. We are physically wired differently. This describes the basics, beyond this is pure unestablished sets of theories. We are different in kind.
dhw: I really don’t think there are many people who would say that we are exactly the same as our fellow primates, and I doubt if many people would say that elephants are the same “kind” as whales or ants or the duckbilled platypus. Yes, we are different, and our language is a million times more complicated than that of our fellow animals, and we are self-aware and very clever. But that still doesn’t mean that your God’s sole purpose from the very start was to create us, and that elephants, whales, ants and the duckbilled platypus were specially designed simply to provide food until he could specially design us.
DAVID: Ah, it seems you have forgotten that 'different in kind' refers to the other primates we left behind and also Adler's theory which supports our assent to the top pf the heap. All the animals you listed are obviously foodstuff, and not on the point of my comment, Another of your inventive neatly formed sidesteps.
I have no objections at all to your saying that we are a different species (= different in kind) from our fellow primates, just as our fellow primates are different in kind from elephants, whales and ants, and I could hardly have made it clearer that in terms of language, self-awareness and cleverness we are top of the heap. All life, including ourselves, is ultimately foodstuff. I simply object to your assumption that this means we were your God’s goal from the very beginning, and he specially designed everything else over 3+ billion years for the sole purpose of providing food until he could specially design us. This is the logical gap which you prefer to sidestep rather than bridge.
Human evolution; theory of hominin language
by David Turell , Saturday, December 15, 2018, 14:25 (2168 days ago) @ dhw
QUOTE: "There are at least three elements of language only present in hominins:
First, is a fine-control over our vocal tracts. Other apes are likely born with a more limited repertoire of vocalizations. The difference comes down to how our brains are wired: Humans have direct connections between the neurons controlling our voice box and the motor cortex, the region of our brain responsible for voluntary movements. Brain scans show these connections are lacking in other primates. (David's bold)DAVID: Note my bold. We are physically wired differently. This describes the basics, beyond this is pure unestablished sets of theories. We are different in kind.
dhw: I really don’t think there are many people who would say that we are exactly the same as our fellow primates, and I doubt if many people would say that elephants are the same “kind” as whales or ants or the duckbilled platypus. Yes, we are different, and our language is a million times more complicated than that of our fellow animals, and we are self-aware and very clever. But that still doesn’t mean that your God’s sole purpose from the very start was to create us, and that elephants, whales, ants and the duckbilled platypus were specially designed simply to provide food until he could specially design us.
DAVID: Ah, it seems you have forgotten that 'different in kind' refers to the other primates we left behind and also Adler's theory which supports our assent to the top pf the heap. All the animals you listed are obviously foodstuff, and not on the point of my comment, Another of your inventive neatly formed sidesteps.
dhw: I have no objections at all to your saying that we are a different species (= different in kind) from our fellow primates, just as our fellow primates are different in kind from elephants, whales and ants, and I could hardly have made it clearer that in terms of language, self-awareness and cleverness we are top of the heap. All life, including ourselves, is ultimately foodstuff. I simply object to your assumption that this means we were your God’s goal from the very beginning, and he specially designed everything else over 3+ billion years for the sole purpose of providing food until he could specially design us. This is the logical gap which you prefer to sidestep rather than bridge.
What is logical to me is illogical to you. What you describe is what we see. All I have done is said God did it. God can do it any way He wants.
Human evolution; theory of hominin language
DAVID: Ah, it seems you have forgotten that 'different in kind' refers to the other primates we left behind and also Adler's theory which supports our assent to the top of the heap. All the animals you listed are obviously foodstuff, and not on the point of my comment, Another of your inventive neatly formed sidesteps.
dhw: I have no objections at all to your saying that we are a different species (= different in kind) from our fellow primates, just as our fellow primates are different in kind from elephants, whales and ants, and I could hardly have made it clearer that in terms of language, self-awareness and cleverness we are top of the heap. All life, including ourselves, is ultimately foodstuff. I simply object to your assumption that this means we were your God’s goal from the very beginning, and he specially designed everything else over 3+ billion years for the sole purpose of providing food until he could specially design us. This is the logical gap which you prefer to sidestep rather than bridge.
DAVID: What is logical to me is illogical to you. What you describe is what we see. All I have done is said God did it. God can do it any way He wants.
If you had only said God did it, there would be no problem. But you insist that he specifically preprogrammed or personally dabbled every innovation, econiche, lifestyle and natural wonder over 3.5+ billion years, and did so for the sole purpose of providing food until he specifically designed H. sapiens – his only goal for creating life. You can’t explain why he “chose” this method, even though he was always in full control and could have done it any way he wanted. If you can’t think of an explanation, how can you say it is logical to you? In the four theistic alternative explanations I have given you, which you acknowledge to be logical, God still did it, and in the hypothesis that I have offered, your God could still have done it by inventing the original mechanisms that propelled evolution. But you reject all these logical God-did-it possibilities in favour of the one you can't understand.
Human evolution; theory of hominin language
by David Turell , Sunday, December 16, 2018, 14:45 (2167 days ago) @ dhw
DAVID: Ah, it seems you have forgotten that 'different in kind' refers to the other primates we left behind and also Adler's theory which supports our assent to the top of the heap. All the animals you listed are obviously foodstuff, and not on the point of my comment, Another of your inventive neatly formed sidesteps.
dhw: I have no objections at all to your saying that we are a different species (= different in kind) from our fellow primates, just as our fellow primates are different in kind from elephants, whales and ants, and I could hardly have made it clearer that in terms of language, self-awareness and cleverness we are top of the heap. All life, including ourselves, is ultimately foodstuff. I simply object to your assumption that this means we were your God’s goal from the very beginning, and he specially designed everything else over 3+ billion years for the sole purpose of providing food until he could specially design us. This is the logical gap which you prefer to sidestep rather than bridge.
DAVID: What is logical to me is illogical to you. What you describe is what we see. All I have done is said God did it. God can do it any way He wants.
dhw: If you had only said God did it, there would be no problem. But you insist that he specifically preprogrammed or personally dabbled every innovation, econiche, lifestyle and natural wonder over 3.5+ billion years, and did so for the sole purpose of providing food until he specifically designed H. sapiens – his only goal for creating life. You can’t explain why he “chose” this method, even though he was always in full control and could have done it any way he wanted. If you can’t think of an explanation, how can you say it is logical to you? In the four theistic alternative explanations I have given you, which you acknowledge to be logical, God still did it, and in the hypothesis that I have offered, your God could still have done it by inventing the original mechanisms that propelled evolution. But you reject all these logical God-did-it possibilities in favour of the one you can't understand.
Human evolution; theory of hominin language
by David Turell , Sunday, December 16, 2018, 15:09 (2167 days ago) @ dhw
DAVID: Ah, it seems you have forgotten that 'different in kind' refers to the other primates we left behind and also Adler's theory which supports our assent to the top of the heap. All the animals you listed are obviously foodstuff, and not on the point of my comment, Another of your inventive neatly formed sidesteps.
dhw: I have no objections at all to your saying that we are a different species (= different in kind) from our fellow primates, just as our fellow primates are different in kind from elephants, whales and ants, and I could hardly have made it clearer that in terms of language, self-awareness and cleverness we are top of the heap. All life, including ourselves, is ultimately foodstuff. I simply object to your assumption that this means we were your God’s goal from the very beginning, and he specially designed everything else over 3+ billion years for the sole purpose of providing food until he could specially design us. This is the logical gap which you prefer to sidestep rather than bridge.
DAVID: What is logical to me is illogical to you. What you describe is what we see. All I have done is said God did it. God can do it any way He wants.
dhw: If you had only said God did it, there would be no problem. But you insist that he specifically preprogrammed or personally dabbled every innovation, econiche, lifestyle and natural wonder over 3.5+ billion years, and did so for the sole purpose of providing food until he specifically designed H. sapiens – his only goal for creating life. You can’t explain why he “chose” this method, even though he was always in full control and could have done it any way he wanted. If you can’t think of an explanation, how can you say it is logical to you? In the four theistic alternative explanations I have given you, which you acknowledge to be logical, God still did it, and in the hypothesis that I have offered, your God could still have done it by inventing the original mechanisms that propelled evolution. But you reject all these logical God-did-it possibilities in favour of the one you can't understand.
The first bold above is the nubbin of our disagreement. In analyzing God's methods and motives, a conclusion will depend upon one's concept of God. All of both our proposals are logical. I view God as more controlling and purposeful than you do, and therefore favor the proposals I've given. You can't explain God any more than I can. What is logical to you is logical to me. It is not an issue of my understanding. You have misunderstood my comment about God and His use of evolution (second bold). My thought has always been, why did He evolve life if He had the capability to do direct creation as in Genesis? Since it happened it was obviously His choice of method of creation. And as I sit here answering you, I am as far removed from apehood as anything you can imagine. We are the current endpoint. If God used evolution to guide creation and we are the current result, I just accept it as a logical conclusion that we have been His purpose all along. And furthermore, where does evolution go in the future? Superhumans? Same endpoint! Flying humans? We already have that. Case closed.
Human evolution; theory of hominin language
I have combined this thread with "Divine purposes and methods".
Human evolution; how we became marathoners
by David Turell , Tuesday, December 18, 2018, 21:30 (2165 days ago) @ dhw
A gene has been found, which allowed us to run down prey. We sweat, they don't:
https://www.scientificamerican.com/article/simple-genetic-mutation-helped-humans-become...
"Roughly two million to three million years ago, a primate moved from the forest to the savanna. It grew longer legs, larger muscles and wider feet. It developed sweat glands that allowed it to remain cool under the blazing African sun. It was also around this time, according to recent research, that a mutation in a single gene called CMAH spread throughout the species. Now a study in mice supports the idea that this genetic tweak enabled humans to run long distances and hunt their prey to exhaustion.
"According to biologist Ajit Varki of the University of California, San Diego, the mutation rendered the CMAH gene completely inactive. Varki wondered if there was a link between this genetic event and a knack for long-distance running. Because all humans share the same nonfunctional gene, he could not simply compare the running abilities of people with different versions of it. But he had spent years studying mice bred to have the same CMAH inactivation as humans to gain insight into diabetes, cancer and muscular dystrophy. Varki's work suggested a link between CMAH loss and muscle biology, but he needed proof.
“'For about 10 years I've been trying to convince somebody in my lab to put these mice on a treadmill,” Varki says. When he finally did the experiment, “lo and behold, without any training, [the CMAH-deficient mice] were one and a half times better at running.” The rodents' muscles—especially those in their hind limbs—used oxygen more efficiently and were more resistant to fatigue.
"In 2004 Harvard University biologist Daniel Lieberman had hypothesized that running—as opposed to bipedal locomotion alone—played a major role in human evolution. Lieberman, who was not involved in the new mouse research, says it is “the first really good, careful genetic study that fits our predictions” about running's role in the rise of modern humans."
Comment: You can easily overheat your dog by jogging with him at a distance that is too far. On two feet we obviously needed this ability to run down game. We trded hair for sweat glands. It is another way we are different in kind rather than degree from apes and monkeys.
Human evolution; are we a danger to the Earth?
by David Turell , Tuesday, December 25, 2018, 00:42 (2158 days ago) @ David Turell
This op-ed thinks so:
http://science.sciencemag.org/content/362/6420/1242
"Earth is in the throes of a mass extinction event and climate change upheaval, risking a planetary shift into conditions that will be extremely challenging, if not catastrophic, for complex life (1). Although responsibility for the present trajectory is unevenly distributed, the overarching drivers are rapid increases in (i) human population, (ii) consumption of food, water, energy, and materials, and (iii) infrastructural incursions into the natural world. As the “trends of more” on all these fronts continue to swell, the ecological crisis is intensifying (2–4). Given that human expansionism is causing mass extinction of nonhuman life and threatening both ecological and societal stability, why is humanity not steering toward limiting and reversing its expansionism?
"The rational response to the present-day ecological emergency would be to pursue actions that will downscale the human factor and contract our presence in the realm of nature. Yet in mainstream institutional arenas, economic, demographic, and infrastructural growth are framed as inevitable, while technological and management solutions to adverse impacts are pursued single-mindedly. Although pursuing such solutions is important, it is also clear that reducing humanity's scale and scope in the ecosphere is the surest approach to arresting the extinction crisis, moderating climate change, decreasing pollution, and providing sorely needed leeway to tackle problems of poverty, food insecurity, and forced migration
***
"The planetwide sense of entitlement bequeathed by a supremacist worldview blinds the human collective to the wisdom of limitations in several ways, thereby hindering efforts to address the ecological crisis by downscaling the human enterprise and withdrawing it from large portions of land and sea.
***
"The reigning human-nature hierarchical worldview thus hinders the recognition that scaling down and pulling back is the most farsighted path forward. Scaling down involves reducing the overall amount of food, water, energy, and materials that humanity consumes and making certain shifts in what food, energy, and materials are used. This quantitative and qualitative change can be achieved by actions that can lower the global population within a human-rights framework, shrink animal agriculture, phase out fossil fuels, and transform an extractionist, overproducing, throwaway, and polluting economy into a recycling, less busy, thrifty, more ecologically benign economy. (my bold)
***
"To pursue scaling down and pulling back the human factor requires us to reimagine the human in a register that no longer identifies human greatness with dominance within the ecosphere and domination over nonhumans. The present historical time invites opening our imagination toward a new vision of humanity no longer obstructed by the worldview of human supremacy. Learning to inhabit Earth with care, grace, and proper measure promises material and spiritual abundance for all."
Comment: Please note my bold above. It points out how bubbled-headed this Utopian opinion-piece comes across. Only in a dictatorship of Communist China was ever birth controlled! When I was born the Earth had two billion folks. We are now over seven billion in less than ninety years. But guess what is happening? In the West birth rate is below replacement rate all on its own. It is the other folks who are multiplying and producing those numbers. Third world countries need help in modern economic development As that happens the birth rate will drop as it has elsewhere. Experts estimate a sustainable human population is best around ten billion.
Any thoughts, anyone?
Human evolution; are we a danger to the Earth?
QUOTES: The reigning human-nature hierarchical worldview thus hinders the recognition that scaling down and pulling back is the most farsighted path forward. Scaling down involves reducing the overall amount of food, water, energy, and materials that humanity consumes and making certain shifts in what food, energy, and materials are used. This quantitative and qualitative change can be achieved by actions that can lower the global population within a human-rights framework, shrink animal agriculture, phase out fossil fuels, and transform an extractionist, overproducing, throwaway, and polluting economy into a recycling, less busy, thrifty, more ecologically benign economy. (David’s bold)
"To pursue scaling down and pulling back the human factor requires us to reimagine the human in a register that no longer identifies human greatness with dominance within the ecosphere and domination over nonhumans. The present historical time invites opening our imagination toward a new vision of humanity no longer obstructed by the worldview of human supremacy. Learning to inhabit Earth with care, grace, and proper measure promises material and spiritual abundance for all."
DAVID’s comment: Please note my bold above. It points out how bubbled-headed this Utopian opinion-piece comes across. Only in a dictatorship of Communist China was ever birth controlled! When I was born the Earth had two billion folks. We are now over seven billion in less than ninety years. But guess what is happening? In the West birth rate is below replacement rate all on its own. It is the other folks who are multiplying and producing those numbers. Third world countries need help in modern economic development As that happens the birth rate will drop as it has elsewhere. Experts estimate a sustainable human population is best around ten billion.
Any thoughts, anyone?
Human arrogance, ignorance, greed and lust for power are certainly posing a huge threat to the overall ecosystem on which our survival depends. And I think we would all agree that “Learning to inhabit Earth with care, grace, and proper measure promises material and spiritual abundance for all”. But the “Utopia” does not depend on birth control alone, and regulating birth does not depend on help in modern economic development. On the contrary, modern economic development is precisely what has triggered many of the other threats the author has listed, and for which we in the West are the prime culprits, having set the example for “extractionist, overproducing, throwaway, polluting economies”. I don’t think our own drop in birth rate has anything to do with our concern for the future of the planet or with modern economic development. There has been a huge cultural shift, and many western folk now are far more focused on their careers, their lifestyles and/or simply earning a living than on making children, whereas even today a woman with no children is not seen as fulfilled in many non-western societies. Perhaps the answer is education, but that does not necessarily mean western education. Ancient cultures have a lot to teach us about respect for Nature. So how can Utopia be achieved? To be blunt, I don’t think it can. Ant society is probably the nearest life can get. (But Aldous Huxley's Brave New World is a scary example of a Utopia I don't think any of us would want.) If God exists, he may have a few ideas of his own!
Human evolution; are we a danger to the Earth?
by David Turell , Thursday, December 27, 2018, 22:25 (2156 days ago) @ dhw
QUOTES: The reigning human-nature hierarchical worldview thus hinders the recognition that scaling down and pulling back is the most farsighted path forward. Scaling down involves reducing the overall amount of food, water, energy, and materials that humanity consumes and making certain shifts in what food, energy, and materials are used. This quantitative and qualitative change can be achieved by actions that can lower the global population within a human-rights framework, shrink animal agriculture, phase out fossil fuels, and transform an extractionist, overproducing, throwaway, and polluting economy into a recycling, less busy, thrifty, more ecologically benign economy. (David’s bold)
"To pursue scaling down and pulling back the human factor requires us to reimagine the human in a register that no longer identifies human greatness with dominance within the ecosphere and domination over nonhumans. The present historical time invites opening our imagination toward a new vision of humanity no longer obstructed by the worldview of human supremacy. Learning to inhabit Earth with care, grace, and proper measure promises material and spiritual abundance for all."
DAVID’s comment: Please note my bold above. It points out how bubbled-headed this Utopian opinion-piece comes across. Only in a dictatorship of Communist China was ever birth controlled! When I was born the Earth had two billion folks. We are now over seven billion in less than ninety years. But guess what is happening? In the West birth rate is below replacement rate all on its own. It is the other folks who are multiplying and producing those numbers. Third world countries need help in modern economic development As that happens the birth rate will drop as it has elsewhere. Experts estimate a sustainable human population is best around ten billion.
Any thoughts, anyone?
dhw: Human arrogance, ignorance, greed and lust for power are certainly posing a huge threat to the overall ecosystem on which our survival depends. And I think we would all agree that “Learning to inhabit Earth with care, grace, and proper measure promises material and spiritual abundance for all”. But the “Utopia” does not depend on birth control alone, and regulating birth does not depend on help in modern economic development. On the contrary, modern economic development is precisely what has triggered many of the other threats the author has listed, and for which we in the West are the prime culprits, having set the example for “extractionist, overproducing, throwaway, polluting economies”. I don’t think our own drop in birth rate has anything to do with our concern for the future of the planet or with modern economic development. There has been a huge cultural shift, and many western folk now are far more focused on their careers, their lifestyles and/or simply earning a living than on making children, whereas even today a woman with no children is not seen as fulfilled in many non-western societies. Perhaps the answer is education, but that does not necessarily mean western education. Ancient cultures have a lot to teach us about respect for Nature. So how can Utopia be achieved? To be blunt, I don’t think it can. Ant society is probably the nearest life can get. (But Aldous Huxley's Brave New World is a scary example of a Utopia I don't think any of us would want.) If God exists, he may have a few ideas of his own!
Medically woman who put off birth into their 30's or 40's are doing a great disservice to themselves, by making more complications in pregnancy and birth. But this points out is DHW's comments. Humans do what humans want to do for themselves with thinking more widely.
Human evolution; our dads are different than ape dads
by David Turell , Thursday, January 17, 2019, 21:02 (2135 days ago) @ David Turell
A new study shows how different:
https://aeon.co/essays/the-devotion-of-the-human-dad-separates-us-from-other-apes?utm_s...
"Among our close animal relatives, only humans have involved and empathic fathers. Why did evolution favour the devoted dad?
***
"So necessary is this trait to the survival of our species that it is underpinned by an extensive, interrelated web of biological, psychological and behavioural systems that evolved over the past half a million years. Yet, until 10 years ago, we had neglected to try to understand this trait, due to the misguided assumption that it was of no significance – indeed, that it was dispensable. This trait is human fatherhood,
***
"To understand the role of the father, we must first understand why it evolved in our species of ape and no other. The answer inevitably lies in our unique anatomy and life history. As any parent knows, human babies are startlingly dependent when they are born. This is due to the combination of a narrowed birth canal – the consequence of our bipedality – and our unusually large brains, which are six times larger than they should be for a mammal of our body size.
***
"This has meant that, to ensure the survival of mother and baby and the continued existence of our species, we have evolved to exhibit a shortened gestation period, enabling the head to pass safely through the birth canal. The consequence of this is that our babies are born long before their brains are fully developed. But this reduced investment in the womb has not led to an increased, compensatory period of maternal investment after birth. Rather, the minimum period of lactation necessary for a child to survive is likewise drastically reduced; the age at weaning of an infant child can be as young as three or four months. A stark contrast to the five years evident in the chimp. Why is this the case?
"If we, as a species, were to follow the trajectory of the chimpanzee, then our interbirth interval (the time between the birth of one baby and the next) would have been so long; so complex and so energy-hungry is the human brain that it would have led to an inability to replace – let alone increase – our population. So, evolution selected for those members of our species who could wean their babies earlier and return to reproduction, ensuring the survival of their genes and our species. But because the brain had so much development ahead of it, these changes in gestation and lactation lengths led to a whole new life-history stage – childhood – and the evolution of a uniquely human character: the toddler.
***
"But 500,000 years ago, our ancestors’ brains made another massive leap in size, and suddenly relying on female help alone was not enough. This new brain was energetically hungrier than ever before. Babies were born more helpless still, and the food – meat – now required to fuel our brains was even more complicated to catch and process than before. Mum needed to look beyond her female kin for someone else. Someone who was as genetically invested in her child as she was. This was, of course, dad.
"Without dad’s input, the threat to the survival of his child, and hence his genetic heritage, was such that, on balance, it made sense to stick around. Dad was incentivised to commit to one female and one family while rejecting those potential matings with other females, where his paternity was less well-assured.
***
"Mothers, still focused on the production of the next child, would be restricted in the amount of hands-on life experience they could give their teenagers, so it was dad who became the teacher.
"This still rings true for the fathers whom my colleagues and I research, across the globe, today. In all cultures, regardless of their economic model, fathers teach their children the vital skills to survive in their particular environment.
***
"Fathers are so critical to the survival of our children and our species that evolution has not left their suitability for the role to chance. Like mothers, fathers have been shaped by evolution to be biologically, psychologically and behaviourally primed to parent. We can no longer say that mothering is instinctive yet fathering is learned.
"The hormonal and brain changes seen in new mothers are mirrored in fathers. Irreversible reductions in testosterone and changes in oxytocin levels prepare a man to be a sensitive and responsive father, attuned to his child’s needs and primed to bond – and critically, less motivated by the search for a new mate. As a man’s testosterone drops, the reward of chemical dopamine increases; this means that he receives the most wonderful neurochemical reward of all whenever he interacts with his child.
***
"Men have evolved to father and to be an equal but crucially different part of the parenting team. By not acknowledging who they are or supporting what they do, we are really missing a trick. Some 80 per cent of men aspire to become fathers. I believe it is time we made the effort to get to know who they really are."
Comment: Very long extremely interesting article. It all seems to be the fault of such a huge brain size and the time to become adult.. No ape does this.
Human evolution; our 7-8 hour sleep pattern is not ape-like
by David Turell , Thursday, January 24, 2019, 20:13 (2128 days ago) @ David Turell
Parts of the world still have several periods of sleep, but most of the advanced world it is one long patch of seven-plus hours. No apes or other animals are like this:
http://discovermagazine.com/2019/jan/to-sleep-perchance-to-evolve?utm_source=Yesmail&am...
"First off, we sleep less. While humans average seven hours, other primates range from just under nine hours (blue-eyed black lemurs) to 17 (owl monkeys). Chimps, our closest living evolutionary relatives, average about nine and a half hours. And although humans doze for less time, a greater proportion is rapid eye movement sleep (REM), the deepest phase, when vivid dreams unfold.
***
"While the costs of sleep are obvious — an animal is vulnerable to predators and other threats, and loses opportunities to find food and mates — the benefits are not. Different hypotheses about why we need sleep include neural development and upkeep, memory processing and immune defense, but there’s no consensus.
"Sleep habits also differ drastically among species. Elephants get by with two hours of shut-eye, while armadillos need 20. Researchers have found several factors that influence these variations in sleep patterns. For example, animals with high metabolisms sleep less — presumably because they spend more time awake and eating. And animals with bigger brains spend a greater portion of sleep in REM.
***
"In a 2018 study in the American Journal of Physical Anthropology, Samson and colleague Charles Nunn, an anthropologist at Duke University, employed a sophisticated statistical method to compare the sleep patterns found in 30 primate species, including our own. They found, says Samson, that humans are significant “evolutionary outliers.” We sleep less but spend about 10 percent more of our total sleep time in REM than expected. Human sleep is shorter and deeper — in other words, more efficient — than that of our closest relatives.
"The finding supports a hypothesis proposed by the duo in 2015: Efficient sleep gave our hominin ancestors an evolutionary edge. By shortening total duration, hominins reduced their time as unconscious targets for predators, and added waking hours to complete essential tasks, like learning, securing resources and maintaining social bonds.
"It’s also still unknown when our ancestors evolved this unusual sleep pattern. Samson speculates it may have emerged when they became too large to sleep in trees, roughly 2 million years ago with Homo erectus. While other apes avoid predators by building arboreal nests, it’s possible that hominins sleeping on the ground evolved more efficient sleep to allow them to spend more time awake — and on the alert for potential threats.
"Based on nearly 70 studies across cultures, including those without electricity or 9-to-5 workdays, Samson and Nunn determined that humans sleep an average of seven hours out of every 24. But, says Samson, “where it gets tricky is that when you look across cultures, the way those seven hours are expressed can be pretty flexible.”
"In contemporary industrialized societies, people typically sleep for one continuous bout. But other cultures divide sleep over multiple sessions, through daytime napping or two nighttime episodes, separated by about an hour of wakefulness.
The latter was the norm for humans before the Industrial Revolution, according to research by historian Roger Ekirch. In preindustrial documents, Ekirch identified over a thousand mentions of so-called first and second sleep, and activities done between, such as chores, prayers, even visiting neighbors. Found in newspapers, court records, diaries and literature, from Homer’s Odyssey to Leo Tolstoy’s War and Peace, the references permeate more than 2,000 years of recorded culture.
"The habit of segmented sleep was shed by the early 1900s, likely due to artificial lighting and changing societal views that equated single-bout sleep with productivity and prosperity. Yet Ekirch believes it persists, among Westerners who spontaneously wake in the middle of the night, “a persistent echo of a pattern of sleep ... dominant for literally thousands of years.”
***
"According to the sentinel hypothesis, staggered sleep evolved to ensure that there was always some portion of a group awake and able to detect threats.
***
" In a 2017 study in Proceedings of the Royal Society B, Samson gave activity trackers, which can approximate sleep time, to a community of Hadza hunter-gatherers in Tanzania. Over 20 nights, there were only 18 one-minute periods when everyone was asleep. Most of the time, about 40 percent of the group was active.
"The study “suggested there’s some type of mechanism set in place where there’s individuals alert, protecting everyone, while most everyone is asleep,” says Samson. This could explain how our ancestors avoided danger while enjoying deep, REM-packed sleep.
"It also fits the idea that the pattern emerged around 2 million years ago, when ancestors like H. erectus abandoned the safety of trees for a fully terrestrial life. Efficient, sentinel-style sleep may have then spurred advances in brain power, technology and social cooperation seen in later hominins. "
Comment: this is an other way we differ from all primates. Our brain seems to require it.
Human evolution; our faces are smaller, show more emotion
by David Turell , Tuesday, April 16, 2019, 01:46 (2046 days ago) @ David Turell
Interesting proposal involving living in cities and the ease of getting food, et c.:
https://cosmosmagazine.com/biology/face-facts-we-have-evolved-to-communicate
"Writing in the journal Nature Ecology and Evolution, an international team proposes that our faces evolved not just because of factors such as diet and climate, but also to provide more opportunities for gesture and non-verbal communication.
"'We can now use our faces to signal more than 20 different categories of emotion via the contraction or relaxation of muscles", says Paul O'Higgins, from the University of York in the UK.
"'It's unlikely that our early human ancestors had the same facial dexterity as the overall shape of the face and the positions of the muscles were different.
"The researchers traced changes in the evolution of the face from the early African hominins to the appearance of modern human anatomy and conclude that they are the result of a combination of biomechanical, physiological and social influences.
"Human faces are more slender that those of other hominins, and they have a smoother forehead with more visible, hairy eyebrows capable of a greater range of movement. This allows us to express a wide range of subtle emotions, including recognition and sympathy.
***
"The human face has been partly shaped by the mechanical demands of feeding and over the past 100,000 years they have been getting smaller as our developing ability to cook and process food led to a reduced need for chewing, the researchers say.
"This facial shrinking process has become particularly marked since the agricultural revolution, as we switched from being hunter gatherers to agriculturalists and then to living in cities – lifestyles that led to increasingly pre-processed foods and less physical effort.
"'Softer modern diets and industrialised societies may mean that the human face continues to decrease in size", O'Higgins says. "There are limits on how much the human face can change…for example breathing requires a sufficiently large nasal cavity.
"'However, within these limits, the evolution of the human face is likely to continue as long as our species survives, migrates and encounters new environmental, social and cultural conditions.'"
Comment: Interesting concept. We certainly use voice, hands and facial expressions to express ourselves. These are minor changes; we are still H. sapiens sapiens and I think only minor changes of this sort are all that will happen in the future. See the illustrated skulls on the website
Human evolution; our complex speech mechanism;English
by David Turell , Monday, April 22, 2019, 01:24 (2040 days ago) @ dhw
English is considered very complex:
https://cosmosmagazine.com/social-sciences/it-s-official-english-is-a-genuinely-weird-l...
"Some computational linguists have, however, used data in the World Atlas of Language Structures (WALS) to explore which languages might be considered the “weirdest”. This was not just a value judgement: they systematically compared the information in the WALS website for 239 languages from different parts of the world.
"Their aim was to find out which languages had the largest number of features that differed most from other languages. In this survey, English came in 33rd position out of 239 languages. So it was definitely “weirder” than over 80% of the other languages in the survey.
***
"English probably sounds a little “weird” to many speakers of other languages. According to the WALS, the average number of distinctive speech sounds in the world’s languages is about 25-30 – known as “phonemes”. Pirahã, an indigenous language spoken in the Amazon region of Brazil, has an unusually small set of phonemes. It has eight consonants, and just three vowels: /i/, /a/ and /o/. In contrast, Taa – also known as !Xóõ) is a language in southern Africa which has more than 100 phonemes, including many different types of click sounds. Sign languages, such as British Sign Language or American Sign Language, do not use sounds at all. Signs are, instead, composed out of combinations of handshapes, movements of the hands, and locations on or near the body of the signer.
"English has more phonemes than many languages, with around 44, depending on which variety of English you speak. It has an unusually large set of vowel sounds – there are around 11. According to WALS, most spoken languages only have between five to six vowel sounds. This is part of the reason that English spelling is fiendishly complicated, because it has inherited five letters for vowels from the Roman alphabet and speakers have to make them work for more than twice that number of sounds.
"English has some comparatively unusual consonant sounds as well. Two sounds, those represented by the “th” in “bath” and “bathe” respectively, are found in fewer than 10% of the languages surveyed in WALS. In fact, these two sounds are generally among the last sounds acquired by children, with some adult varieties of English not using them at all.
'English grammar is also “weird”. English uses varying word orders to distinguish between questions and statements – meaning that the subject of the sentence precedes the verb in statements. Take the phrase “life is a box of chocolates” for example. Here, the order is subject (“life”) followed by the verb (“is”). In the question, “is life a box of chocolates?”, the order of these elements is reversed.
"In a WALS survey of 955 languages, fewer than 2% of languages in the sample used English-like differences in sentence structure for questions. Over 50% of the languages added a question particle to differentiate a question from a statement.
In Japanese, for example, you add the question particle “ka” to a statement to turn it into a question. The second most common strategy in WALS was to change the intonation pattern, such as changing a falling intonation pattern (for a statement) to a rising one (for a question). In contrast, Mixtec (an indigenous language of Mexico) is a highly atypical language because it does not use any grammatical strategy to distinguish between questions and statements.
"That said, it is impossible to conclusively make the argument that English is, or isn’t, “weird” because all the data needed to make this judgement is not available. As several thousand languages have not yet been included in WALS, this means WALS can only be used to compare English with a small proportion of the estimated 7000 languages in the world today. So more language documentation is ultimately needed to give a better understanding of the world’s amazing linguistic diversity.
Comment: Only humans use the invented 7,000+ languages that exist. Different in kind, no question. We each have the capacity to learn all we wish. As for 'weird English', it conveys meanings in words more exactly than almost all other languages with over 550,000 words and counting.
Human evolution; our complex speech mechanism;English
DAVID: English is considered very complex:
https://cosmosmagazine.com/social-sciences/it-s-official-english-is-a-genuinely-weird-l...
QUOTE: "Some computational linguists have, however, used data in the World Atlas of Language Structures (WALS) to explore which languages might be considered the “weirdest”. This was not just a value judgement: they systematically compared the information in the WALS website for 239 languages from different parts of the world.
"Their aim was to find out which languages had the largest number of features that differed most from other languages. In this survey, English came in 33rd position out of 239 languages. So it was definitely “weirder” than over 80% of the other languages in the survey.
This must be one of the “weirdest” projects ever to be awarded a research grant. They forgot to mention that English is therefore less “weird” than under 20% of other languages, which of course proves…exactly what? And why is this “weird”? The largest number of different features is the largest number of different features.
DAVID: Only humans use the invented 7,000+ languages that exist. Different in kind, no question. We each have the capacity to learn all we wish. As for 'weird English', it conveys meanings in words more exactly than almost all other languages with over 550,000 words and counting.
Yes, that is very true: only humans use human languages. And I agree that bacterial, insect, fish, bird, animal languages are different in kind from human language. I’m sorry to say that I don’t know enough of the 7000+ human languages to confirm that English conveys more meanings than 80% of them. However, having spent a lifetime speaking, writing, studying and lecturing on the English language, I can confirm that it is constantly evolving and provides a wonderfully complex system with a vast potential for expression. Out of respect for my European friends, I must also confirm that the same can be said of French, German and Spanish. I shall now apply for a grant to further my research into the weirdest uses of research grants.
Human evolution; our complex speech mechanism;English
by David Turell , Monday, April 22, 2019, 15:27 (2040 days ago) @ dhw
DAVID: English is considered very complex:
https://cosmosmagazine.com/social-sciences/it-s-official-english-is-a-genuinely-weird-l...QUOTE: "Some computational linguists have, however, used data in the World Atlas of Language Structures (WALS) to explore which languages might be considered the “weirdest”. This was not just a value judgement: they systematically compared the information in the WALS website for 239 languages from different parts of the world.
"Their aim was to find out which languages had the largest number of features that differed most from other languages. In this survey, English came in 33rd position out of 239 languages. So it was definitely “weirder” than over 80% of the other languages in the survey.This must be one of the “weirdest” projects ever to be awarded a research grant. They forgot to mention that English is therefore less “weird” than under 20% of other languages, which of course proves…exactly what? And why is this “weird”? The largest number of different features is the largest number of different features.
DAVID: Only humans use the invented 7,000+ languages that exist. Different in kind, no question. We each have the capacity to learn all we wish. As for 'weird English', it conveys meanings in words more exactly than almost all other languages with over 550,000 words and counting.
dhw: Yes, that is very true: only humans use human languages. And I agree that bacterial, insect, fish, bird, animal languages are different in kind from human language. I’m sorry to say that I don’t know enough of the 7000+ human languages to confirm that English conveys more meanings than 80% of them. However, having spent a lifetime speaking, writing, studying and lecturing on the English language, I can confirm that it is constantly evolving and provides a wonderfully complex system with a vast potential for expression. Out of respect for my European friends, I must also confirm that the same can be said of French, German and Spanish. I shall now apply for a grant to further my research into the weirdest uses of research grants.
I was quoting from the book, The Mother Tongue, 1990, which gave a history of the language.
Human evolution; our complex speech mechanism;
by David Turell , Friday, May 01, 2020, 15:48 (1665 days ago) @ David Turell
A connection in humans to the frontal cortex is found to have early evidence in macaques from 20-25 million years ago:
https://bigthink.com/mind-brain/speech-20-million-years?rebelltitem=4#rebelltitem4
"Researchers find traces of something like our arcuate fasciculus in macaque brains.
"Since the last ancestor we shared with macaques was 25-30 million years ago, this would push speech way back.
"The study suggests human speech began in the auditory cortex and eventually extended to include the executive-function areas of the brain.
"As far as we know, humans alone are capable of speech as we know it, with words and sentences. This has to do, scientists believe, with a pathway in the brain we possess. Now a new and controversial study reports the presence of this same pathway, albeit in less pronounced form, in macaques. Given that our last shared ancestor with these monkeys was 25-30 million years ago,
***
"The fuss is about a neural pathway in humans called the arcuate fasciculus, or AF, that traverses our prefrontal cortex and frontal lobe. Recent research suggests it has connections to other brain regions as well.
"'This is a pathway that interconnects brain regions that are important for language. If this pathway or some of these regions it interconnects are damaged because of stroke or brain degeneration a person might immediately (because of stroke) or progressively (because of dementia) lose the ability to understand or to produce language," Petkov tells Newsweek.
***
"For the study, international teams of European and US scientists pored through new imaging data of humans looking for evidence of this pathway in other regions. They found a segment of it, unexpectedly, in the auditory complexes of both brain hemispheres, though most strongly identifiable in the left one. Says Petkov, "To be honest, we were really quite surprised that the auditory system has this privileged pathway to vocal production regions in frontal cortex." He adds, "That in itself tells us that there is something special about this pathway. The link to projection from the auditory system to frontal cortex regions, which in humans supports language, is fascinating."
***
"Finding an AF-like pathway in macaques may not even represent their earliest development, notes Petkov, who points out, "there may be more brain 'fossils' yet to be discovered with even earlier evolutionary origins. Or it may be discovered that the origin of this pathway traces back even further if another brain "fossil" is found.'"
Comment: Tracts in the brain have to begin development somewhere in time as evolution progressed to produce humans and their ability to have speech and language. As always I view this a God's preplanning for the future
Human evolution; our complex speech mechanism
QUOTE: "Finding an AF-like pathway in macaques may not even represent their earliest development, notes Petkov, who points out, "there may be more brain 'fossils' yet to be discovered with even earlier evolutionary origins. Or it may be discovered that the origin of this pathway traces back even further if another brain "fossil" is found.'"
DAVID: Tracts in the brain have to begin development somewhere in time as evolution progressed to produce humans and their ability to have speech and language. As always I view this a God's preplanning for the future.
I agree totally with your first sentence, because I believe in common descent. What mystifies me is that your now totally hands-on God apparently only wanted to directly design H. sapiens, but first he had to directly design the arcuate fasciculus 20-25million years ago, and then all the other bits and pieces over the next umpteen millions of years just to produce our voices. Fortunately, you’ve given us your answer to the mystery under “David’s Theory of Evolution”.
Human evolution; our complex speech mechanism
by David Turell , Saturday, May 02, 2020, 16:04 (1664 days ago) @ dhw
QUOTE: "Finding an AF-like pathway in macaques may not even represent their earliest development, notes Petkov, who points out, "there may be more brain 'fossils' yet to be discovered with even earlier evolutionary origins. Or it may be discovered that the origin of this pathway traces back even further if another brain "fossil" is found.'"
DAVID: Tracts in the brain have to begin development somewhere in time as evolution progressed to produce humans and their ability to have speech and language. As always I view this a God's preplanning for the future.
dhw: I agree totally with your first sentence, because I believe in common descent. What mystifies me is that your now totally hands-on God apparently only wanted to directly design H. sapiens, but first he had to directly design the arcuate fasciculus 20-25million years ago, and then all the other bits and pieces over the next umpteen millions of years just to produce our voices. Fortunately, you’ve given us your answer to the mystery under “David’s Theory of Evolution”.
I am still surprised at your surprise. I've always said God speciated. In the book we worked on Atheist Delusion, there is a section you will remember on a vertebral change from 20+ million years ago that foretold upright posture. I always point out pre-planning when I see it. Do you deny the possibility that God planed ahead as He designed advances in evolution? Pre-planning, advanced programming, dabbling are all just reasonable guesses as to His methodology. You always debate them as if they were written on stone, when they can't be.
Human evolution; using gestures
by David Turell , Saturday, May 15, 2021, 19:12 (1286 days ago) @ David Turell
All humans can communicate this way:
https://www.sciencemag.org/news/2021/05/no-shared-language-no-problem-people-across-cul...
"One of the hardest questions for evolutionary linguists is why humans speak at all. When people don’t share a language, they quickly resort to using their hands, rather than their voices: It’s easier to mime “drink” than it is to make a noise that sounds like drinking. Those gestures, over time, can easily blossom into full-fledged sign languages. “If gesture is good enough for language,” says Aleksandra Ćwiek, a linguistics Ph.D. student at the Leibniz-Centre General Linguistics, “why the hell do we talk?”
"In a new study, Ćwiek and her colleagues help answer that question: People from very different cultures can understand nonlinguistic vocal clues better than expected by chance, they find. Speakers of 28 languages could all successfully guess meanings in a charadeslike game where other people expressed words like “water” using vocal sounds—but no language.
***
"They found that participants could guess general meanings surprisingly well. Each correct meaning was presented along with five incorrect options, so guessing at random would give participants a 17% chance of being right. But on average, people across all languages guessed correctly 65% of the time, they report this week in Scientific Reports. That’s enough to show participants often understood the clues, researchers say.
"Some words were easier than others: Participants nearly always correctly guessed the sound for “sleep.” But guesses for the more abstract “that” and “gather” scraped in only just above chance. English speakers were correct 74% of the time, suggesting a shared culture helps, says senior author Marcus Perlman, a linguist at the University of Birmingham. But the lowest score, for Thai speakers, was 52%—still far above chance.
"To cast the cultural net even wider, the researchers also tested participants in communities that seldom use written language. This included speakers of three additional languages in Vanuatu, French Guiana, and Brazil. Rather than asking people to choose the written word that matched the clue they heard, they were asked to choose pictures, limiting the test to concepts that could be shown in a photograph.
"Again, people were surprisingly good at the task. Participants were correct at least 34% of the time (compared with 8% if they’d been right by chance), with Daakie speakers from Vanuatu getting nearly half the answers right. “It’s cool to think that we … can communicate meaning just with the sound of our voice,” Perlman says. “People don’t just make meaningless sounds.”
***
"Although it’s simple, it challenges an old and central idea in linguistics: that there’s no relationship between the sounds that make up a word and the meaning of that word. For instance, there’s nothing about the word “cat” that is obviously connected to the animal. But this study adds to a growing pile of evidence that iconicity in speech isn’t limited to just the rare case of onomatopoeia, like “meow.”
"If vocalization, like gesture, can convey meaning without being part of a language, it could have played a role in the emergence of early linguistic systems, Perlman says. The finding makes it possible for linguists to start to explore how vocalization and gesture might have worked in tandem in the evolution of language, Raviv says, rather than arguing about which came first: “It makes the mystery of the shift from gesture to spoken language obsolete.'”
Comment: Certainly erectus using its enlarged brain got by with a few understood words and lots of gestures. That even unrelated language speakers could guess meanings is very significant.
Human evolution; newborn brains wired for word recognition
by David Turell , Monday, September 27, 2021, 18:52 (1151 days ago) @ David Turell
Shown by very early fMRI's:
https://www.sciencedaily.com/releases/2020/10/201022125525.htm
"Humans are born with a part of the brain that is prewired to be receptive to seeing words and letters, setting the stage at birth for people to learn how to read, a new study suggests. Analyzing brain scans of newborns, researchers found that this part of the brain -- called the 'visual word form area' (VWFA) -- is connected to the language network of the brain.
***
"The VWFA is specialized for reading only in literate individuals. Some researchers had hypothesized that the pre-reading VWFA starts out being no different than other parts of the visual cortex that are sensitive to seeing faces, scenes or other objects, and only becomes selective to words and letters as children learn to read or at least as they learn language.
"'We found that isn't true. Even at birth, the VWFA is more connected functionally to the language network of the brain than it is to other areas," Saygin said. "It is an incredibly exciting finding."
***
"The researchers analyzed fMRI scans of the brains of 40 newborns, all less than a week old, who were part of the Developing Human Connectome Project. They compared these to similar scans from 40 adults who participated in the separate Human Connectome Project.
"The VWFA is next to another part of visual cortex that processes faces, and it was reasonable to believe that there wasn't any difference in these parts of the brain in newborns, Saygin said.
"As visual objects, faces have some of the same properties as words do, such as needing high spatial resolution for humans to see them correctly.
"But the researchers found that, even in newborns, the VWFA was different from the part of the visual cortex that recognizes faces, primarily because of its functional connection to the language processing part of the brain.
"'The VWFA is specialized to see words even before we're exposed to them," Saygin said.
***
"'Our study really emphasized the role of already having brain connections at birth to help develop functional specialization, even for an experience-dependent category like reading.'"
Comment: Was this wiring arrangement present 70,000 years ago when it is thought complex language developed or did the brain circuits evolve quickly since then? I think God had the brains pre-wired and therefore ready to accommodate the new skill.
Human evolution; language and abstract concepts
by David Turell , Tuesday, December 11, 2018, 17:32 (2172 days ago) @ David Turell
edited by David Turell, Tuesday, December 11, 2018, 17:54
Our language ability allows us to have abstract concepts:
https://mindmatters.ai/2018/12/how-is-human-language-different-from-animal-signals/
"A hallmark of human beings is the ability to use language. No other species of animal has language, although other species are capable of understanding and communicating quite a few things. Yet (non-human) animal communications cannot properly be called language. A closer look at human language and animal communication, and at the function language serves for us reveals important things about the human mind and about what it is to be human.
***
"A designator, however, is a kind of sign that differs in a very important way from a signal. A designator points to an object, but it does so abstractly, not concretely. The spoken or written word “cat” has nothing physically to do with a cat. Unlike a gesture (pointing to a cat) or making the sound “meow”, the letters C-A-T feature nothing that concretely links the word to the animal. You only know what “cat” designates if you understand the word as used in English. By contrast, you could understand a signal like pointing to a cat or saying “meow” even if you spoke no English. Designators differ from signals in that they point to objects—things or concepts—abstractly.
"Language is the systematic use of designators—the rule-based use of abstract signs. That is why a lion’s roar, an ape’s gesture, or a bird’s song are not really language. They are signals. A signal is not rule-based (signals have no grammar) and signals are concrete, not abstract.
"Only humans have language because only humans are capable of rule-based abstract signing. Animals can often employ complex signals but no animal uses rule-based designators. Animals that can be trained to communicate using “language” (such as parrots or apes) are using words as signals, not as designators. For example, you can train your dog to go fetch the leash when you say “Do you want to go for a walk?” because he has learned to fetch the leash in response to those sounds, which he hears as a signal. He does not understand them as a grammatical construction and will certainly not go on to discuss the weather forecast with you. His communication is concrete, not abstract.
***
"What is the purpose of language? Why does man, and no other animal, use language in addition to signals? As linguist Noam Chomsky has pointed out, the purpose of language is not essentially to communicate. Signals work well for communication. Language permits more complex communication under some circumstances but some signals are quite complex and serve to facilitate communication quite well. Sign language, which is mostly a system of signals, is a quite effective means of communication, even of conveying abstractions, but it is not (except when it signs the alphabet) language. It is derived from language.
"The purpose of language is not primarily to communicate. The purpose of language is to enable man to think in a human way. Man alone is capable of abstract thought—thought about concepts that are universals, and not particular things. Man thinks about justice, and about mercy, about politics and imaginary numbers, and about countless concepts that are not particular physical things. This is abstract thought, and only humans think abstractly.
"Animals are limited to thought about particulars. Dogs think about the food in their bowl. Humans think about nutrition. Dogs think about the good feeling they get when they are petted. Humans think about joy and love in an abstract sense. Both humans and animals have the capacity to think about particulars. Only humans also have the capacity to think about abstract concepts.
"Every thought is about something. All thought is intentional, in the technical philosophical sense that it points to something. Thoughts about particular things—physical objects in the environment, imagination, or memory—are akin to signals.
"But humans cannot think abstractly using signals. A signal points to a physical thing—a physical (or imagined or remembered) object. An abstract concept, such as mercy or justice, is not a physical thing. In order to think abstractly, we must use abstract signs—designators—to point to the conceptual objects of our thoughts. Consider: How could we contemplate mercy if we did not have the word “mercy,” if our thoughts were restricted to concrete objects (akin to signals)? We could imagine situations, persons, or objects that might be associated with mercy but we couldn’t contemplate mercy itself unless we had a word for it. Mercy isn’t a physical thing we can point to.
"Language, which is the rule-based use of abstract designators, is essential for abstract thought because only designators can point to things that have no concrete physical existence. Only human beings think abstractly, and language is what makes abstract thought possible."
Comment: This clearly shows humans are different in kind, not degree. Only we have abstract thought and are aware we are aware. See: Tuesday, December 11, 2018, 17:32
Human evolution; language and abstract concepts
by David Turell , Thursday, January 26, 2023, 15:35 (665 days ago) @ David Turell
Using symbols 20,000 years ago:
https://www.discovermagazine.com/the-sciences/ancient-humans-first-written-words-are-20...
"When was writing initially invented? Though anthropologists and archaeologists tend to accept that the oldest written word appeared around 5,000 years ago, a new paper published in the Cambridge Archaeology Journal pushes this date back by about 15,000 years.
"According to the paper, Ice Age individuals scored and painted strange symbols, including dots, slashes and asterisks, on rock surfaces inside and outside of caves and across portable items such as sticks and stones, to record the seasonal activities of their favorite animals. If these findings stand up under scrutiny, it may mean that our ancient ancestors were much more advanced than previously appreciated.
“'The ability to assign abstract signs to phenomena in the world […] to record past events and predict future events was a profound intellectual achievement,” the researchers posit in their paper.
"Ice Age individuals adorned an assortment of surfaces across France and Spain with representations of regional prey animals, from bison to birds to fish, approximately 20,000 years ago. And sometimes, in caves such as Lascaux, Chauvet and Altamira, these representations were augmented with stunning sequences of abstract symbols, whose meanings still stump anthropologists and archaeologists today.
"Working with the supposedly “uncontroversial” assumption that these sequences maintained some sort of notational or numerical meaning to their makers, a team of researchers recently assessed a series of 862 animal representations from the Upper Paleolithic to translate the three widest spread symbols: the dot, the slash and the y-shaped sign.
"Ultimately, the team surmised that the number and the placement of these symbols related information about the mating and birthing of their associated animals, which was of the utmost importance to individuals of the time.
***
"After a cursory review, the researchers realized that all of the sequences contained no more than 13 marks.
"Using statistical analysis to scrutinize these animal-and-sequence associations further, comparing patterns of birthing, mating and migration to patterns of dots, slashes and strokes, the team found that the simple dots and slashes symbolized the number of synodic months after the start of the spring (out of the total of 13) that the associated animals started to mate. Alternatively, they found that the placement of the Y-shaped strokes symbolized the beginning of the species’ birthing season.
"According to the authors, while the sequences may not constitute the “full-blown” form of the written word, they certainly comprise a preliminary phase in the transition to writing.
“'Perhaps it is best described as a proto-writing system,” the researchers add in their study."
Comment: symbols show abstract thought, and this could well be the beginning of written lauguage.
Human evolution; migration on plate tectoncis
by David Turell , Tuesday, February 14, 2023, 18:06 (646 days ago) @ David Turell
Floating along with the plates' movements. Simply moving land masses helped humans spread out:
https://www.sciencealert.com/scientists-reveal-how-humans-first-populated-the-ancient-m...
"Between 75,000 and 50,000 years ago, humans began to make their way across the megacontinent of Sahul, a landmass that connected what is now Australia, Tasmania, New Guinea, and the Aru Islands.
"New research reveals more about the routes used by these early humans and the length of time it took for them to fully explore the extremities of Sahul. It could have taken up to 10,000 years for the vast area to be completely covered by these intrepid humans, which is twice as long as previously thought.
"To refine their estimates, researchers developed a new, more sophisticated model that factored in influences on travel, like the land's ability to provide food, water source distribution, and the landscape's topography.
"'The ways that people interact with terrain, ecology, and potentially other people alter our model outcomes, providing more realistic results," says ecologist Corey Bradshaw from Flinders University in Australia.
"'We now have a good prediction of the patterns and processes of how people first settled these lands tens of thousands of years ago."
***
'Migration most likely began through Timor, then later through western parts of New Guinea. Rapid expansion would then have happened southward toward the Great Australian Bight and northward to New Guinea.
***
'Whether it's preferring a route through two mountains rather than over them or keeping close to water sources, these details can be significant when it comes to where populations spread and how quickly.
"'This also goes to show the power of combining computational models with archaeology and anthropology for refining our understanding of humanity," says archaeologist Stefani Crabtree from Utah State University.
Comment: sailing over the seas obviously happened as in teh a cific, but following land masses makes perfect sense. See the illustrations.
Human evolution; innate number sense in babies
by David Turell , Thursday, February 16, 2023, 00:10 (644 days ago) @ David Turell
Giant review article which comes down on the side, yes they do:
https://www.scientificamerican.com/article/babies-are-born-with-an-innate-number-sense/
"In the 17th century John Locke rejected this idea, insisting that the human mind begins as a tabula rasa, or blank slate, with almost all knowledge acquired through experience. This view, known as empiricism, in contrast to Plato's nativism, was later further developed by John Stuart Mill, who argued that we learn two plus three is five by seeing many examples where it holds true: two apples and three apples make five apples, two beers and three beers make five beers, and so on.
"In short, empiricism dominated philosophy and psychology until the second half of the 20th century, when nativist-friendly thinkers such as Noam Chomsky swung the pendulum back toward Plato. Chomsky focused on language, proposing that children are born with an innate language instinct that enables them to quickly acquire their first language with little in the way of explicit instruction.
"Others then extended Chomsky's hypothesis to mathematics. In the late 1970s cognitive scientists C. R. Gallistel and Rochel Gelman argued that children learn to count by mapping the number words in their language onto an innate system of preverbal counting that humans share with many other animals. In his landmark book The Number Sense, first published in 1997, French neuroscientist Stanislas Dehaene drew attention to the converging evidence for this preverbal system, helping researchers from diverse disciplines—animal cognition, developmental psychology, cognitive psychology, neuroscience, education—realize they were all studying the same thing.
"In our 2021 paper in the journal Behavioral and Brain Sciences, we argued that there is no longer a serious alternative to the view that humans and many nonhuman animals have evolved a capacity to process numbers. Whereas Plato proposed that we have innate mathematical knowledge, or a capacity to think about numbers, we argue that we have innate mathematical perception—an ability to see or sense numbers."
Comment: there follows an enormous number of studies arguing the point. Knowing the innate sense of numbers position they favor, studies they describe are barely convincing.
Human evolution; our neocortex appears do novo
by David Turell , Thursday, February 16, 2023, 00:43 (644 days ago) @ David Turell
edited by David Turell, Thursday, February 16, 2023, 00:49
There is no past anticendent form:
https://www.quantamagazine.org/gene-expression-in-neurons-solves-a-brain-evolution-puzz...
"The neocortex stands out as a stunning achievement of biological evolution. All mammals have this swath of tissue covering their brain, and the six layers of densely packed neurons within it handle the sophisticated computations and associations that produce cognitive prowess. Since no animals other than mammals have a neocortex, scientists have wondered how such a complex brain region evolved.
"For more than 50 years, some evolutionary neuroscientists have argued that the neocortex and the DVR were both derived from a more primitive feature in an ancestor shared by mammals and reptiles.
"Now, however, by analyzing molecular details invisible to the human eye, scientists have refuted that view. By looking at patterns of gene expression in individual brain cells, researchers showed that despite the anatomical similarities, the neocortex in mammals and the DVR in reptiles are unrelated. Instead, mammals seem to have evolved the neocortex as an entirely new brain region, one built without a trace of what came before it. The neocortex is composed of new types of neurons that seem to have no precedent in ancestral animals. (my bold)
***
" The discovery that gene expression can reveal these kinds of important distinctions between neurons is also prompting researchers to rethink how they define some brain regions and to reassess whether some animals might have more complex brains than they thought.
***
"...brain regions do not evolve neatly one on top of another. Instead, the brain evolves as a whole, with older parts undergoing modifications to adapt to the addition of new parts, explained Paul Cisek, a cognitive neuroscientist . “It’s not like upgrading your iPhone, where you load up a new app,” he said.
***
"The debate over the origins of the neocortex and DVR stretched out over decades. Now, however, a recently developed technique is helping to break the stalemate. Single-cell RNA sequencing enables scientists to read out which genes are being transcribed in a single cell. From these gene expression profiles, evolutionary neuroscientists can identify a wealth of detailed differences between individual neurons. They can use those differences to determine how evolutionarily similar the neurons are.
***
"...differences in gene expression suggested that the reptilian DVR and the mammalian neocortex evolved independently from different regions of the brain.
“'The 2018 paper was really a landmark paper in that it was the first really comprehensive molecular characterization of neural types between mammals and reptiles,” said Bradley Colquitt, a molecular neuroscientist at the University of California, Santa Cruz.
***
"Mammals, however, were a different story. Salamander neurons didn’t match anything in the mammalian neocortex, although they did resemble cells in parts of the mammalian brain outside the neocortex.
"Moreover, several kinds of cells in the neocortex — specifically, the types of pyramidal neurons that make up the majority of neurons in the structure — didn’t match with cells in the reptiles either. Tosches and her colleagues therefore suggested that these neurons evolved solely in mammals. They aren’t the first researchers to propose that origin for the cells, but they are the first to produce evidence for it using the powerful resolution of single-cell RNA sequencing.
***
"Tosches and her team propose that essentially all of the mammalian neocortex is an evolutionary innovation. So while at least part of the reptilian DVR was adapted from the brain region of an ancestral creature, the mammalian neocortex evolved as a new brain region burgeoning with novel cell types. Their answer to the decades of debate is that the mammalian neocortex and the reptile DVR are not homologous because they don’t have a common origin.
***
"The new answer from Tosches’ team doesn’t mean that the neocortex in mammals evolved to sit neatly atop older brain regions, as the triune brain theory proposed. Instead, as the neocortex expanded and new types of pyramidal neurons were born within it, other brain regions kept evolving in concert with it. They didn’t just hang on as an ancient “lizard brain” underneath. It’s even possible that the complexity emerging in the neocortex pushed other brain regions to evolve — or vice versa.
***
"First they compared the full array of neural cell types in each species to find the ones that they shared, which must have been passed down from a common ancestor. Then they looked for neural cell types that differed between the species.
"Their results showed that both conserved and novel neural cell types are found all over the brain — not just in the brain regions that appeared more recently. The entire brain is a “mosaic” of old and new cell types, said Justus Kebschull, an evolutionary neuroscientist at Johns Hopkins University."
Comment: No surprise. If the Cambrian explosion had no precursors, so did the specialized pyramidal neurons of our cortex. A designer can add anything new He wishes. This is a 'neuron gap' as significant as the Cambrian. The new cells will obviously push around the placement of old ones, so the whole brain continues to evolve. dhw take notice.
Human evolution; our neocortex appears de novo II
by David Turell , Thursday, February 16, 2023, 01:20 (644 days ago) @ David Turell
edited by David Turell, Thursday, February 16, 2023, 01:54
Further viewpoint:
dhw has had tremendous trouble shaking off Darwinian evolution concepts, which, by definition, has each new form coming from precursors. A designer needs no precursors. He can plug in something new at any point he wishes. DHW has constantly complained about this. Why did God wait until the Cambrian period to pull this stunt he asks? All we know is it happened when it did. Now we have a second big gap in the sudden arrival of special neurons in mammalian brains leading up to humans. This should settle dhw's issue. NO PRECURSORS REQUIRED in designed evolution. Darwin envisioned chance evolution with natural selection weeding out the best ones to remain in competition for the future living forms. That form of evolution requires precursors. God doesn't.
Human evolution: an early tunicate relative found
by David Turell , Friday, July 07, 2023, 16:39 (503 days ago) @ David Turell
From Utah Cambrian shale:
https://www.sciencemagazinedigital.org/sciencemagazine/library/item/07_july_2023/411356...
"In 2019, a finger-size fossil landed on the desk of Karma Nanglu, a paleontologist at Harvard University who specializes in the Cambrian and Ordovician periods, when many of today’s animal forms made their entrance. The specimen had sat for years in the drawer of a Salt Lake City museum; its finders, who had pulled it from a fossil-rich layer of Cambrian limestone in western Utah, thought it might be a sea squirt or tunicate—a marine invertebrate that shares a distant ancestor with all vertebrates.
***
"Now, in a paper published in Nature Communications this week, Nanglu and his coauthors report that the exquisitely-preserved 500-million-year-old fossil is a dead ringer for some tunicates today, with two siphons to filter organic particles from the water and complex musculature controlling the siphons. “It looks like a tunicate that died yesterday and just happened to fall down on some rock,” says Nicholas Treen, a developmental biologist at Princeton University who wasn’t involved in the work. The discovery offers clues to the timing and development of early tunicates and could even push back the date for the origin of tunicates’ sister group, the vertebrates, including humans.
"Today, some 3000 species of tunicate live in almost every habitat of the oceans. Most have a two-part life cycle, including a free-swimming, tadpolelike larva that settles and metamorphoses into a stationary adult. Tunicate larvae have a notochord, the precursor to a spinal column—a defining trait of the group called chordates, which includes all vertebrates. But only a handful of tunicate fossils exist, for reasons paleontologists can’t fully explain.
***
"As a tunicate matures, its siphon muscles develop from the same cells that form cardiac tissue in modern vertebrates. The muscles’ presence in Megasiphon means it may have already had something like a heart, even though its internal structures aren’t preserved. “Since you can see these atrial siphon muscles, you can almost take it for granted that there is a beating, vertebrate-like heart inside this organism,” Treen says.
"The fossil addresses a long-unresolved question in early chordate evolution: whether the common ancestor to all tunicates was a free-swimming organism or rooted to the bottom. Megasiphon, with its resemblance to living, sessile tunicates, strongly supports the latter hypothesis. The find suggests that tunicates’ two-part life history and ability to metamorphose is an ancestral characteristic of the group."
Comment: Gould described another animal with a notochord at that time interval, the Pikaia, in his book, Wonderful Life. And later in China in 1995 more forms were found.
Human evolution; our complex speech mechanism
by David Turell , Wednesday, February 27, 2019, 05:19 (2094 days ago) @ David Turell
Some animals can mimic our speech but only humans have coordinated speech and language:
https://www.knowablemagazine.org/article/mind/2019/why-speech-human-innovation
"It’s true that humans, and humans alone, evolved the complex set of voice, hearing and brain-processing skills enabling full-scale sophisticated vocal communication. Yet animals can make complicated sounds; parrots can mimic human speech and cats can clearly convey that it’s time for a treat. Many animals possess an acute sense of hearing and are able to distinguish random noises from intentional communication. So even though only humans possess the complete linguistic package, the components of language ability “have very deep evolutionary roots,” says Fitch, of the University of Vienna.
"Much of the physiological apparatus for hearing and speaking is found in all land-dwelling vertebrates — the tetrapods — including mammals, birds, amphibians and reptiles. “Humans share a significant proportion of our basic machinery of hearing and vocal production with other tetrapods,”
"Life-forms occupying numerous branches of the tree of life possess anatomical tools for producing and perceiving vocal communication. Where human ability exceeds our predecessors, Fitch says, is the sophistication of the brain circuitry adapted to the uniquely human capacity for complex linguistic expression.
***
"Among the tetrapods, mammals evolved much more sensitive hearing, able to cope with a wider range of frequencies and therefore more able to process nuances of vocalizations. Humankind’s primate ancestors, for instance, possessed highly capable hearing ability. “There is nothing about the human ear that is strikingly different from that of other primates,” Fitch writes. “Our peripheral hearing apparatus was in place, in our primate ancestors, in essentially modern form long before we evolved the capacity for speech.”
***
"Besides all that, parrots and many other bird species, some bats and even elephants can mimic vocal sounds. So humans’ distinctive speech can’t depend solely on vocal production ability. Considering all the evidence, the vocal and auditory skills of various animals tell a tale of multiple preludes to the human speech story. That tale reveals that humans acquired speech not via anatomical innovation for vocalizing and hearing, but by novel neural connections that control the anatomical hardware.
"After all, speech requires more than producing and perceiving sounds. A speaker’s brain must decide what sounds to produce and issue instructions for producing them to the body’s vocal apparatus. And a listener’s brain must be able to decode auditory signals it receives and then issue commands for a vocal response. People are skillful at producing sounds in response to other sounds — it’s why you can repeat a word out loud after the first time you hear it.
"Such controlled vocalization of a word is different from just making noise. Most animals possess neural circuitry for producing “innate” vocalizations: Dogs bark, squirrels chatter and seagulls squawk. Even humans have their own innate vocalizations, including crying, laughter and screams. But among primates, only humans have the “capacity to produce novel, learned vocalizations beyond the innate call repertoire,” Fitch notes.
"Today the dominant hypothesis explaining that ability is the presence of special connections between brain regions involved in controlling speech and hearing. Innate calls — in humans and all other mammals — are initiated by direct signals from the brain stem. Indirect messaging from the cortex (the brain’s more advanced outer layer) enables voluntary suppression or production of innate calls. Unlike other animals, humans possess direct connections between nerve cells in the cortex and the nerve cells that control the muscles operating the larynx. Some apes and monkeys have direct connections from cortex to the muscles controlling the lips and tongue, but not to the muscles controlling the larynx. (Circuitry connecting the auditory cortex to the motor cortex also seem more extensively developed in humans.)
***
“'The genetic underpinnings of … [neural] connections involved in human vocal control are virtually unknown,”
***
“'Language is more than speech,” said Friederici, director of the Max Planck Institute for Human Cognitive and Brain Sciences, in Leipzig, Germany. “Speech … uses a limited set of vowels and consonants to form words. Language, however, is a system consisting of words … and a set of rules called grammar or syntax to form phrases and sentences.”
"Nonhuman primates can learn the meaning of individual words, she notes, but aren’t capable of combining words into meaningful sequences of any substantial length. That ability also depends on circuitry connecting different parts of the brain, current research by Friederici, collaborators and other scientists is now showing.
"Understanding that circuitry depends on comparing the cellular architecture and nerve fiber tracts of the human brain with the brain of animals with lesser linguistic power. So in a way, scientists may be able to ask animals for clues not only to the evolution of speech, but to language skills more generally as well. Sort of like going straight to the source and asking the horse."
Comment: As usual we are different in kind, not degree, as vocal animals have lots of the parts we have but not the brain controls.
Human evolution; early upright posture
by David Turell , Thursday, February 28, 2019, 18:55 (2093 days ago) @ David Turell
New anatomic studies review the ability to walk upright and climb trees:
https://phys.org/news/2019-02-upright-human-ancestors.html
"Scott W. Simpson, Ph.D., led an analysis of a 4.5 million-year-old fragmentary female skeleton of the human ancestor Ardipithecus ramidus that was discovered in the Gona Project study area in the Afar Regional State of Ethiopia.
"The newly analyzed fossils document a greater, but far from perfect, adaptation to bipedalism in the Ar. ramidus ankle and hallux (big toe) than previously recognized. "Our research shows that while Ardipithecus was a lousy biped, she was somewhat better than we thought before," said Simpson.
***
"The new analysis, published in the Journal of Human Evolution, thus points to a diversity of adaptations during the transition to how modern humans walk today. "The fact that Ardipithecus could both walk upright, albeit imperfectly, and scurry in trees marks it out as a pivotal transitional figure in our human lineage," said Simpson.
"Key to the adaptation of bipedality are changes in the lower limbs. For example, unlike monkeys and apes, the human big toe is parallel with the other toes, allowing the foot to function as a propulsive lever when walking. While Ardipithecus had an offset grasping big toe useful for climbing in trees, Simpson's analysis shows that it also used its big toe to help propel it forward, demonstrating a mixed, transitional adaptation to terrestrial bipedalism.
"Specifically, Simpson looked at the area of the joints between the arch of the foot and the big toe, enabling him to reconstruct the range of motion of the foot. While joint cartilage no longer remains for the Ardipithecus fossil, the surface of the bone has a characteristic texture which shows that it had once been covered by cartilage. "This evidence for cartilage shows that the big toe was used in a more human-like manner to push off," said Simpson. "It is a foot in transition, one that shows primitive, tree-climbing physical characteristics but one that also features a more human-like use of the foot for upright walking." Additionally, when chimpanzees stand, their knees are "outside" the ankle, i.e., they are bow-legged. When humans stand, the knees are directly above the ankle—which Simpson found was also true for the Ardipithecus fossil.
Comment: this an obvious transitional fossil, but full blown speciation requiring design. I don't believe the cells of the common ancestor of chimps and humans could conceive of how to design a foot and spine and pelvis for bipdal movement.
Human evolution; diet change and 'f', 'v' speech ability
by David Turell , Monday, March 18, 2019, 00:08 (2075 days ago) @ David Turell
A softer diet and development of upper teeth overhang allowed the easier use of labiodental sounds:
https://cosmosmagazine.com/biology/you-sound-how-you-eat-speech-evolved-as-diet-changed
"A surprising new study has revealed that diverse sounds produced by human speech not only evolved after Neolithic times, but also stem from biological alterations in the human bite as a result of eating softer diets.
"The findings contradict the theory that the range of human sounds has not changed since Homo sapiens emerged about 300,000 years ago. Linguistic diversity was also commonly thought to evolve independently of biological changes.
"In 1985, linguist Charles Hockett suggested that labiodentals – the class of speech sounds including ‘f’ and ‘v’ in English – might have evolved as diets became softer with the move away from hunting and gathering towards agriculture and industrialised food processing.
"These changes, he said, altered the human bite so that new sounds were easier to produce.
"Damian Blasi and Steven Moran, researchers from the Department of Comparative Linguistics at the University of Zurich in Switzerland, thought the proposal was intriguing.
***
“'So, we set out to test whether we could find such a link between diet, bite and labiodentals.”
"Enlisting a highly interdisciplinary team to investigate, he and colleagues analysed the distribution of labiodentals in contemporary languages.
"They studied how sounds changed through time in the diverse family of Indo-European languages – which includes English, Hindi and Spanish – then modelled the cost of producing labiodentals in a computational model of speech, and scoured paleoanthropological evidence.
"Their investigations revealed that labiodental sounds arose recently, and that they did indeed stem from changes in diet and bite just as Hockett hypothesised.
“'Soft diets led to a preservation of overbite and overjet, which characterises the majority of the bites that people have nowadays,” Blasi explains. These rendered labiodental sounds low cost, or “easy” to produce.
“'Since our upper teeth protrude from our mouth, they can touch the lower lips with very little effort,” he says.
“'Before, heavy wear diets produced an edge-to-edge bite so the upper teeth didn’t protrude, and hence it was harder to produce those sounds. Try it yourself – put your upper and lower teeth in contact then try to produce an ‘f’.”
"The team’s research suggests that the sounds originated not long before the Bronze Age in Europe and Asia. They suspect they emerged from bilabials, another class of speech sounds which include, for instance, ‘b’.
"The authors explore how labiodentals might be “useful” sounds for communicating.
“'They are clearly distinguishable acoustically from other speech sounds and visually salient (think of someone saying the f-word),” Blasi says, adding that ultimately their benefit needs to be further investigated."
Comment: Since speech and language are thought to be recent developments over the past 50,000 years, an appearance of this ability just before the Bronze Age makes for a reasonable timing.
Human evolution; our complex speech mechanism
by David Turell , Tuesday, March 26, 2019, 17:52 (2067 days ago) @ David Turell
It definitely includes the use of meaningful gestures, but just how the brain handles all of this is on partially known:
https://www.quantamagazine.org/how-the-brain-links-gestures-perception-and-meaning-2019...
"The conversion from movement into meaning is both seamless and direct, because we are endowed with the capacity to speak without talking and comprehend without hearing. We can direct attention by pointing, enhance narrative by miming, emphasize with rhythmic strokes and convey entire responses with a simple combination of fingers.
'The tendency to supplement communication with motion is universal, though the nuances of delivery vary slightly. In Papua New Guinea, for instance, people point with their noses and heads, while in Laos they sometimes use their lips. In Ghana, left-handed pointing can be taboo, while in Greece or Turkey forming a ring with your index finger and thumb to indicate everything is A-OK could get you in trouble.
"Despite their variety, gestures can be loosely defined as movements used to reiterate or emphasize a message — whether that message is explicitly spoken or not. A gesture is a movement that “represents action,” but it can also convey abstract or metaphorical information. It is a tool we carry from a very young age, if not from birth; even children who are congenitally blind naturally gesture to some degree during speech. Everybody does it.
"And yet, few of us have stopped to give much thought to gesturing as a phenomenon — the neurobiology of it, its development, and its role in helping us understand others’ actions. As researchers delve further into our neural wiring, it’s becoming increasingly clear that gestures guide our perceptions just as perceptions guide our actions.
***
"No other species points, Novack explained, not even chimpanzees or apes, according to most reports, unless they are raised by people. Human babies, in contrast, often point before they can speak, and our ability to generate and understand symbolic motions continues to evolve in tandem with language. Gesture is also a valuable tool in the classroom, where it can help young children generalize verbs to new contexts or solve math equations. “But,” she said, “it’s not necessarily clear when kids begin to understand that our hand movements are communicative — that they’re part of the message.”
"When children can’t find the words to express themselves, they let their hands do the talking. Novack, who has studied infants as young as 18 months, has seen how the capacity to derive meaning from movement increases with age. Adults do it so naturally, it’s easy to forget that mapping meaning onto hand shape and trajectory is no small feat.
"Gestures may be simple actions, but they don’t function in isolation. Research shows that gesture not only augments language, but also aids in its acquisition. In fact, the two may share some of the same neural systems. Acquiring gesture experience over the course of a lifetime may also help us intuit meaning from others’ motions. But whether individual cells or entire neural networks mediate our ability to decipher others’ actions is still up for debate.
***
"Researchers may not be able to pinpoint the exact cells that help us to communicate and learn with our bodies, but the overlap between multisensory systems is undeniable. Gesture allows us to express ourselves, and it also shapes the way we understand and interpret others. To quote one of Quandt’s papers: “The actions of others are perceived through the lens of the self.”
"So, the next time someone gives you the one-finger salute, take a moment to appreciate what it takes to receive that message loud and clear. If nothing else, it might lessen the sting a bit."
Comment: Gestures are obviously part of language, but how the brain handles them is still understudy. They are obviously very naturally developed and used with meaning, as seen in young children. The major portion of the article is the discussion of many studies that try to reach a conclusion, but all fail so far.
Human evolution; early diet and brain enlargement
by David Turell , Monday, April 01, 2019, 21:00 (2061 days ago) @ David Turell
Our larger brain takes 20% of our calorie intake. Early enlargement before Homo species certainly required a diet higher in calories. This theory about early butchery tries to cover that possibility:
https://www.scientificamerican.com/article/fat-not-meat-may-have-led-to-bigger-hominin-...
"Northern Ethiopia was once home to a vast, ancient lake.
***
"Deposited within these layers are fossils: some of early hominins, along with the bones of hippos, antelope, and elephants. Anthropologist Jessica Thompson encountered two of these specimens, from an area named Dikika, in 2010.
"At the time, she was a visiting researcher at the Institute of Human Origins at Arizona State University. Given no explanation as to their history, she analyzed the bones and found signs of butchery. Percussion marks suggested someone may have accessed the marrow; cut marks hinted that flesh was stripped from bone. To her surprise, the specimens were 3.4 million years old, putting the butcher’s behaviors back 800,000 years earlier than conventional estimates would suggest. That fact got Thompson, now an assistant professor in the department of anthropology at Yale University, thinking there might be more traces of tool use from those early times.
***
"The prevailing view, supported by a confluence of fossil evidence from sites in Ethiopia, is that the emergence of flaked tool use and meat consumption led to the cerebral expansion that kickstarted human evolution more than 2 million years ago. Thompson and her colleagues disagree: Rather than using sharpened stones to hunt and scrape meat from animals, they suggest, earlier hominins may have first bashed bones to harvest fatty nutrients from marrow and brains.
***
"Because large animals such as antelope pack a serious micro-and-macro-nutrient punch, scientists have thought their meat contributed to humanity’s outsized brains. A consensus arose in the 1950s that our ancestors first hunted small animals before moving on to larger beasts around 2.6 million years ago. Flaked tool use and meat eating became defining characteristics of the Homo genus.
***
"Then, starting in the mid-1980s, an opposing theory arose in which Homo’s emergence wasn’t so tightly coupled with the origins of hunting and predatory dominance. Rather, early hominins first accessed brain-feeding nutrients through scavenging large animal carcasses. The debate has rolled on through the decades, with evidence for the scavenging theory gradually building.
***
"Marrow and brains, meanwhile, are locked inside bones and stay fresh longer. These highly nutritional parts are also a precursor to the fatty acids involved with brain and eye development. And more easily than flesh-meat, bones could be carried away from carcass sites, safe from predators.
***
"she says, “This team has shown that marrow may have in fact been more important. It’s a nuance, but an important nuance.”
***
"Evidence suggests hominins shifted their diet around 3.76 million years ago as they took advantage of the open spaces. By around 3.5 million years ago, some species of Australopithecus already showed increased brain sizes, up to 30 percent larger than chimpanzees of comparable body size. Canines had shrunk to proportions later seen in the genus Homo, and hand morphology was already more human than ape, with potential both for terrestrial travel and tool use.
***
"The earliest Homo specimen is now dated to 2.8 million years. The Dikika fossils suggest butchery behaviors at 3.4 million years ago. Homo may have emerged earlier than scientists suspected—a theory that would need more fossil evidence to support it—or another hominin, such as Australopithecus, may have created tools before Homo."
Comment: It is important to recognize extra dietary calories al lowed brain growth, but didn't cause it.
Human evolution; our complex speech mechanism
by David Turell , Tuesday, May 07, 2019, 20:15 (2025 days ago) @ David Turell
With lots of research we still have no idea how the brain produces language:
https://inference-review.com/article/kept-in-mind
"For all the sophistication of their ideas, surprisingly simple questions remain. Which part of our brain carries information forward in time? No one knows. For that matter, no one knows what a symbol is, or where symbolic interactions take place. The formal structures of linguistics and neurophysiology are disjoint, a point emphasized by Poeppel and David Embick in a widely cited study. There is an incommensurability between theories of the brain, TB, and theories of the mind, TM. This is the sort of granularity issue that concerned Poeppel and Embick. TM deals with formal devices and how they interact, while TB deals with waves of different frequencies and amplitudes, and how they overlap in time sequences across brain regions.
***
"Few neuropsychologists have studied how sentences break down into phrases, or how words carry meanings, or why speech is more than just sound. No one has distinguished one thought from another by dissecting brains. Neuroimaging tells us only when some areas of the brain light up selectively. Brain wave frequencies may suggest that different kinds of thinking are occurring, but a suggestion is not an inference—even if there is a connection between certain areas of the brain and seeing, hearing, or processing words. Connections of this sort are not nothing, of course, but neither are they very much. Is this because techniques have not yet been developed to target individual neurons? Or is it because thinking is more subtle than previously imagined?
We may not figure this out within our lifetimes.
***
"When Friederici writes about the “fast computation of the phonological representation,” an obvious inferential lapse is involved.4 Some considerable distance remains between the observation that the brain is doing something and the claim that it is manipulating various linguistic representations. Friederici notes the lapse. “How information content is encoded and decoded,” she remarks, “in the sending and receiving brain areas is still an open issue—not only with respect to language, but also with respect to the neurophysiology of information processing in general.”
***
"Cognitive scientists cannot say how the mass or energy of the brain is related to the information it carries. Everyone expects that more activity in a given area means more information processing. No one has a clue whether it is more information or more articulated information, or more interconnected information, or whether, for that matter, the increased neuro-connectivity signifies something else entirely. Friederici remarks:
"The picture that can be drawn from the studies reviewed here is neuroanatomically quite concise with respect to sensory processes and those cognitive processes that follow fixed rules, namely, the syntactic processes. Semantic processes that involve associative aspects are less narrowly localized.
***
If the perception of a signal presupposes some sensory modality, the modality must swing into action before computation begins. Language in Our Brain is written in the expectation, or the hope, that a division of labor into phonetics, morphology, syntax, semantics, and pragmatics more or less corresponds to the tasks the brain executes in aggregating representations from more elementary bits.
***
"There is also a language network at the molecular level. “Information flows,” Friederici writes, “from the inferior frontal gyrus back to the posterior temporal cortex via the dorsal pathway.” This is, of course, inferential: no one has seen information flowing, if only because no one has ever seen information. But brain events cohere at different levels into a pattern, which is consistent with what can be surmised from brain deficits and injuries. A functional language network, if more abstract than the digestive system, is no less real.
***
“'t is rather unlikely that psychology, on its own, will arrive at the real, lawful characterization of the structure of the mind, as long as it neglects the anatomy of the organ of the mind.” I am left wondering whether neurobiology shouldn’t have to take in all seriousness the central results of cognitive psychology—including the competence/performance divide—if seeking a lawful understanding of the human mind."
Comment: Presented to show just how difficult it is to research and understand the brain and the presence of mind. The enormous complexity demands to understand it was designed.
Human evolution; our complex speech mechanism
by David Turell , Tuesday, May 07, 2019, 22:44 (2025 days ago) @ David Turell
We really do not know how or why it evolved:
https://inference-review.com/article/the-siege-of-paris
"Linguists told themselves many stories about the evolution of language, and so did evolutionary biologists; but stories, as Richard Lewontin rightly notes, are not hypotheses, a term that should be “reserved for assertions that can be tested.”
"The human language faculty is a species-specific property, with no known group differences and little variation. There are no significant analogues or homologues to the human language faculty in other species.5 The notion of a species-specific biological trait is itself unremarkable. Species-specific traits are essential to the very definition of a species, at least for multicellular animals requiring reproductive isolation,
***
"Every human language is a finite computational system generating an infinite array of hierarchically structured expressions. This is the basic property (BP) of language. Every structured expression has a definite semantic interpretation and can be expressed by some sensory modality—speech when possible, gesture when not. The BP is best explained, we argued, as the expression of an underlying computational system, an example of those innate repertoires to which Tinbergen, Lorenz, and Lenneberg called attention.
***
"Citing comparative avian work by Andreas Pfenning et al., we demonstrated that many of the systems for vocal learning and production must have been in place before the emergence of language.17 This follows the typical evolutionary pattern. By the same token, Elizabeth Atkinson et al. carefully reexamined FOXP2 together with the intronic regions that might have been involved in a selective sweep.18 They found that human-specific DNA and amino acid variations matched those of Neanderthals or Denisovans but not other non-human primates.
***
"How far back does language go? There is no evidence of significant symbolic activity before the appearance of anatomically modern humans 200 thousand years ago (kya).22 The South African Blombos cave site contains abstract patterns using ochre crayon on silcrete. These have been dated to approximately 80 kya.23 There is no doubt that these patterns, which represent the earliest known drawings, were executed by anatomically modern humans. In 2018, Dirk Hoffman et al. claimed to have found cave art in Spain dating to roughly 65 kya and thus predating the earliest known arrival of modern humans in Europe.24 Dates have been corrected to approximately 47 kya, the time at which human beings appeared in Europe.
***
"The emergence of language occurred earlier than we thought, and certainly earlier than we suggested.....Riny Huybregts ... concludes that the language faculty emerged with Homo sapiens, or shortly thereafter, but externalization in one form or another must have been a later development, and quite possibly involved little or no evolutionary change.
***
"For all that, the chasm between phenotype, algorithm, and neural implementation remains just that—a chasm. We do not yet understand the space of algorithms that might inform, or guide, the BP.
***
"There is a common, conserved genetic toolkit for building vocal learners, one aligned with neurological wiring. To have understood this is surely progress. With the externalization apparatus for language in place, the rapid emergence of language itself is far easier to explain. Once this part of the story is complete, we will understand in some detail how the printer for human language works and how it evolved.
***
"There is no evidence that great apes, however sophisticated, have any of the crucial distinguishing features of language and ample evidence that they do not.48 Claims made in favor of their semantic powers, we might observe, are wrong. Recent research reveals that the semantic properties of even the simplest words are radically different from anything in animal symbolic systems."
Comment: Before humans developed spoken language there were massive anatomic changes compared to the earliest homos: a dropped pharynx. a protective epiglottis, an arched pallet, special tongue and lip muscles and their brain controls, along with specialized breath controls. All of this appeared before speech. None of this was caused by a need for survival and certainly not driven by environmental demands. In fact none of the development of human characteristics are clearly environmentally driven. Yes, they descended from trees, but that may well have been a voluntary choice to which they then adapted
Human evolution; our complex speech mechanism
DAVID: Before humans developed spoken language there were massive anatomic changes compared to the earliest homos: a dropped pharynx. a protective epiglottis, an arched pallet, special tongue and lip muscles and their brain controls, along with specialized breath controls. All of this appeared before speech. None of this was caused by a need for survival and certainly not driven by environmental demands. In fact none of the development of human characteristics are clearly environmentally driven. Yes, they descended from trees, but that may well have been a voluntary choice to which they then adapted.
As usual you try to make it sound like a fact that all the changes took place BEFORE the actions were possible, whereas I keep proposing that the changes took place BECAUSE the actions were required. (There is no way anyone can possibly prove either hypothesis.) It makes no difference whether a group of primates was forced to descend by environmental change or had a great idea and decided to to venture forth voluntarily. Once the environment had changed, the adaptations were either necessary or desirable to improve their chances of surviving in the new environment. And I would suggest that the new way of living REQUIRED better means of communication, and that the cell communities responded to that need as our ancestors invented new sounds – much as legs would have turned to flippers as the pre-whale cell communities responded to the need for more efficient movement in the water. I propose that it is the effort to make the required changes that causes the cells to restructure themselves – as opposed to a 3.8-billion-year-old computer programme suddenly being switched on, or your God popping in to do some surgery on a group of pharynxes, epiglottises, palates, tongues, lips and brains, with a final announcement: “Now thou canst speak.”
Human evolution; our complex speech mechanism
by David Turell , Wednesday, May 08, 2019, 20:20 (2024 days ago) @ dhw
edited by David Turell, Wednesday, May 08, 2019, 20:40
DAVID: Before humans developed spoken language there were massive anatomic changes compared to the earliest homos: a dropped pharynx. a protective epiglottis, an arched pallet, special tongue and lip muscles and their brain controls, along with specialized breath controls. All of this appeared before speech. None of this was caused by a need for survival and certainly not driven by environmental demands. In fact none of the development of human characteristics are clearly environmentally driven. Yes, they descended from trees, but that may well have been a voluntary choice to which they then adapted.
dhw: As usual you try to make it sound like a fact that all the changes took place BEFORE the actions were possible, whereas I keep proposing that the changes took place BECAUSE the actions were required.
If humans arrived 300,000+ years ago with the anatomic changes for speech now in place well before language developed (per current experts) your statement is entirely false. Did earlier homos and early sapiens speak? Of course they did, but the development of complex language syntax, forming 30 specific different sounds (phonemes) all required the anatomic changes and the larger brain to allow the appearance.
dhw: And I would suggest that the new way of living REQUIRED better means of communication, and that the cell communities responded to that need as our ancestors invented new sounds – much as legs would have turned to flippers as the pre-whale cell communities responded to the need for more efficient movement in the water. I propose that it is the effort to make the required changes that causes the cells to restructure themselves – as opposed to a 3.8-billion-year-old computer programme suddenly being switched on, or your God popping in to do some surgery on a group of pharynxes, epiglottises, palates, tongues, lips and brains, with a final announcement: “Now thou canst speak.”
I view your response a denial of the fossil history as we know it. Reading 'The Ape that Spoke', John Mc Crone, 1991, will explain the points I am making.
From Tuesday, May 07, 2019, 22:44:
"'The emergence of language occurred earlier than we thought, and certainly earlier than we suggested.....Riny Huybregts ... concludes that the language faculty emerged with Homo sapiens, or shortly thereafter, but externalization in one form or another must have been a later development, and quite possibly involved little or no evolutionary change."
Riny Huybregts is saying what I have said from McCrone. Anatomy first
Human evolution; our complex speech mechanism
by David Turell , Wednesday, May 08, 2019, 20:34 (2024 days ago) @ David Turell
DAVID: Before humans developed spoken language there were massive anatomic changes compared to the earliest homos: a dropped pharynx. a protective epiglottis, an arched pallet, special tongue and lip muscles and their brain controls, along with specialized breath controls. All of this appeared before speech. None of this was caused by a need for survival and certainly not driven by environmental demands. In fact none of the development of human characteristics are clearly environmentally driven. Yes, they descended from trees, but that may well have been a voluntary choice to which they then adapted.
dhw: As usual you try to make it sound like a fact that all the changes took place BEFORE the actions were possible, whereas I keep proposing that the changes took place BECAUSE the actions were required.
If humans arrived 300,000+ years ago with the anatomic changes for speech now in place well before language developed (per current experts) your statement is entirely false. Did earlier homos and early sapiens speak? Of course they did, but the development of complex language syntax, forming 30 specific different sounds all required the anatomic changes and the larger brain to allow the appearance.
dhw: And I would suggest that the new way of living REQUIRED better means of communication, and that the cell communities responded to that need as our ancestors invented new sounds – much as legs would have turned to flippers as the pre-whale cell communities responded to the need for more efficient movement in the water. I propose that it is the effort to make the required changes that causes the cells to restructure themselves – as opposed to a 3.8-billion-year-old computer programme suddenly being switched on, or your God popping in to do some surgery on a group of pharynxes, epiglottises, palates, tongues, lips and brains, with a final announcement: “Now thou canst speak.”
I view your response a denial of the fossil history as we know it. Reading 'The Ape that Spoke', John Mc Crone, 1991, will explain the points I am making.
From our thread, Tuesday, May 07, 2019, 22:44:
"'The emergence of language occurred earlier than we thought, and certainly earlier than we suggested.....Riny Huybregts ... concludes that the language faculty emerged with Homo sapiens, or shortly thereafter, but externalization in one form or another must have been a later development, and quite possibly involved little or no evolutionary change."
Riny Huybregts is saying what I have said from McCrone. Anatomy first
Furthermore our sapiens anatomy allow for this language discrimination:
"Phoneme Segmentation
What are phoneme segmentation skills?
Phoneme segmentation is the ability to break words down into individual sounds.
For example, the learner breaks the word run into its component sounds – r, u, and n."
Human evolution; where does A. sediba fit?
by David Turell , Wednesday, May 08, 2019, 21:44 (2024 days ago) @ David Turell
Most likely not a direct ancestor of sapiens:
https://phys.org/news/2019-05-statistical-south-african-fossil-species.html
Statistical analysis of fossil data shows that it is unlikely that Australopithecus sediba, a nearly two-million-year-old, apelike fossil from South Africa, is the direct ancestor of Homo, the genus to which modern-day humans belong.
The research by paleontologists from the University of Chicago, published this week in Science Advances, concludes by suggesting that Australopithecus afarensis, of the famous "Lucy" skeleton, is still the most likely ancestor to the genus Homo.
The first A. sediba fossils were unearthed near Johannesburg in 2008. Hundreds of fragments of the species have since been discovered, all dating to roughly two million years ago. The oldest known Homofossil, the jawbone of an as yet unnamed species found in Ethiopia, is 2.8 million years old, predating A. sediba by 800,000 years.
Despite this timeline, the researchers who discovered A. sediba have claimed that it is an ancestral species to Homo. While it is possible that A. sediba (the hypothesized ancestor) could have postdated earliest Homo (the hypothesized descendant) by 800,000 years, the new analysis indicates that the probability of finding this chronological pattern is highly unlikely.
"It is definitely possible for an ancestor's fossil to postdate a descendant's by a large amount of time," said the study's lead author Andrew Du, Ph.D., who will join the faculty at Colorado State University after concluding his postdoctoral research in the lab of Zeray Alemseged, Ph.D., the Donald M. Pritzker Professor of Organismal and Biology and Anatomy at UChicago.
"We thought we would take it one step further to ask how likely it is to happen, and our models show that the probability is next to zero," Du said.
Du and Alemseged also reviewed the scientific literature for other hypothesized ancestor-descendant relationships between two hominin species. Of the 28 instances they found, only one first-discovered fossil of a descendant was older than its proposed ancestor, a pair of Homo species separated by 100,000 years, far less than the 800,000 years separating A. sediba and earliest Homo. For context, the average lifespan of any hominin species is about one million years.
"Again, we see that it's possible for an ancestor's fossil to postdate its descendant's," Du said. "But 800,000 years is quite a long time."
Alemseged and Du maintain that Australopithecus afarensisis a better candidate for the direct ancestor of Homofor a number of reasons. A. afarensis fossils have been dated up to three million years old, nearing the age of the first Homo jaw. Lucy and her counterparts, including Selam, the fossil of an A. afarensischild that Alemseged discovered in 2000, were found in Ethiopia, just miles from where the Homo jaw was discovered. The jaw's features also resemble those of A. afarensis closely enough that one could make the case it was a direct descendant.
"Given the timing, geography and morphology, these three pieces of evidence make us think afarensisis a better candidate than sediba," Alemseged said. "One can disagree about morphology and the different features of a fossil, but the level of confidence we can put in the mathematical and statistical analyses of the chronological data in this paper makes our argument a very strong one."
Comment: So it seems there were several branches of hominin. I assume as m ore fossils are found we will really establish a full line to sapiens.
Human evolution; our complex speech mechanism
DAVID: Before humans developed spoken language there were massive anatomic changes compared to the earliest homos: a dropped pharynx. a protective epiglottis, an arched pallet, special tongue and lip muscles and their brain controls, along with specialized breath controls. All of this appeared before speech. […]
dhw: As usual you try to make it sound like a fact that all the changes took place BEFORE the actions were possible, whereas I keep proposing that the changes took place BECAUSE the actions were required.
DAVID: If humans arrived 300,000+ years ago with the anatomic changes for speech now in place well before language developed (per current experts) your statement is entirely false. Did earlier homos and early sapiens speak? Of course they did, but the development of complex language syntax, forming 30 specific different sounds (phonemes) all required the anatomic changes and the larger brain to allow the appearance.
The development of syntax has nothing to do with anatomy and phonemes, and there is no expert on earth who can verify that all the anatomic changes took place before early homos and early sapiens began the process of trying to form new sounds.
dhw: And I would suggest that the new way of living REQUIRED better means of communication, and that the cell communities responded to that need as our ancestors invented new sounds […]
DAVID: I view your response a denial of the fossil history as we know it. Reading 'The Ape that Spoke', John Mc Crone, 1991, will explain the points I am making.
From Tuesday, May 07, 2019, 22:44:
"'The emergence of language occurred earlier than we thought, and certainly earlier than we suggested.....Riny Huybregts ... concludes that the language faculty emerged with Homo sapiens, or shortly thereafter, but externalization in one form or another must have been a later development, and quite possibly involved little or no evolutionary change."
How early is irrelevant to your theory. The question is whether the anatomy changed before the different sounds were available, or the anatomy changed because a wider variety became necessary, and the need for change engendered the process of change (as with pre-whale legs turning into flippers). What does “externalization” mean? All forms of language are externalizations – otherwise there would be no communication!
DAVID: Riny Huybregts is saying what I have said from McCrone. Anatomy first
Furthermore our sapiens anatomy allow for this language discrimination:
"Phoneme Segmentation
What are phoneme segmentation skills?
Phoneme segmentation is the ability to break words down into individual sounds.
For example, the learner breaks the word run into its component sounds – r, u, and n."
Obviously! What does that have to do with my proposal that the attempt to create different sounds would have resulted in anatomical change, as opposed to anatomical change preceding the ability to make sounds. However, this is all too rigid. I am not saying that every attempted sound meant/means anatomical change. This is self-evident from the fact that every language stems from the now established anatomy: many sounds made in English are very different from those made in other languages, and vice versa. The question (as with whale flippers) is what CAUSED the anatomical changes in the first place. I propose cell communities responding to the effort to create new sounds, you propose your God’s 3.8-billion-year-old computer programme for epiglottis change – along with every other evolutionary innovation – or your God personally performing operations on a group of individual epiglottises. I find that pretty far-fetched.
Human evolution; our complex speech mechanism
by David Turell , Thursday, May 09, 2019, 22:30 (2023 days ago) @ dhw
DAVID: If humans arrived 300,000+ years ago with the anatomic changes for speech now in place well before language developed (per current experts) your statement is entirely false. Did earlier homos and early sapiens speak? Of course they did, but the development of complex language syntax, forming 30 specific different sounds (phonemes) all required the anatomic changes and the larger brain to allow the appearance.
dhw: The development of syntax has nothing to do with anatomy and phonemes, and there is no expert on earth who can verify that all the anatomic changes took place before early homos and early sapiens began the process of trying to form new sounds.
I've said earlier homos used voice. Complex language requires the appearance of complex anatomic changes to perform enough phonemes to form a complex intelligible language. As for experts read McCrone. The need for the previously enlarged brain is necessary for the language control areas to develop syntax among the aspects of organized language.
dhw: And I would suggest that the new way of living REQUIRED better means of communication, and that the cell communities responded to that need as our ancestors invented new sounds […]DAVID: I view your response a denial of the fossil history as we know it. Reading 'The Ape that Spoke', John Mc Crone, 1991, will explain the points I am making.
From Tuesday, May 07, 2019, 22:44:
"'The emergence of language occurred earlier than we thought, and certainly earlier than we suggested.....Riny Huybregts ... concludes that the language faculty emerged with Homo sapiens, or shortly thereafter, but externalization in one form or another must have been a later development, and quite possibly involved little or no evolutionary change."dhw; How early is irrelevant to your theory. The question is whether the anatomy changed before the different sounds were available, or the anatomy changed because a wider variety became necessary, and the need for change engendered the process of change (as with pre-whale legs turning into flippers). What does “externalization” mean? All forms of language are externalizations – otherwise there would be no communication!
What Huybregts implies to me is anatomy first , sounds next. Exactly what McCrone writes.
DAVID: Riny Huybregts is saying what I have said from McCrone. Anatomy first
Furthermore our sapiens anatomy allow for this language discrimination:
"Phoneme Segmentation
What are phoneme segmentation skills?
Phoneme segmentation is the ability to break words down into individual sounds.
For example, the learner breaks the word run into its component sounds – r, u, and n."dhw: Obviously! What does that have to do with my proposal that the attempt to create different sounds would have resulted in anatomical change, as opposed to anatomical change preceding the ability to make sounds. However, this is all too rigid. I am not saying that every attempted sound meant/means anatomical change. This is self-evident from the fact that every language stems from the now established anatomy: many sounds made in English are very different from those made in other languages, and vice versa. The question (as with whale flippers) is what CAUSED the anatomical changes in the first place. I propose cell communities responding to the effort to create new sounds, you propose your God’s 3.8-billion-year-old computer programme for epiglottis change – along with every other evolutionary innovation – or your God personally performing operations on a group of individual epiglottises. I find that pretty far-fetched.
You have not answered the point that H. sapiens arrived with all the required anatomical changes in place needed to produce human sounds for modern complex language which appears to have started 50,000+ years ago, 250.000 years after the first sapiens arrived. That is Mc Crone's view. Just when did your cell committees do their job?
Human evolution; our complex speech mechanism
dhw: The development of syntax has nothing to do with anatomy and phonemes, and there is no expert on earth who can verify that all the anatomic changes took place before early homos and early sapiens began the process of trying to form new sounds.
DAVID: I've said earlier homos used voice. Complex language requires the appearance of complex anatomic changes to perform enough phonemes to form a complex intelligible language.
All languages, including those of animals, birds and insects, are intelligible to those who use them. But yes of course complex new sounds require complex anatomic changes. The question is why, when and how the changes took place. (See below)
DAVID: As for experts read McCrone. The need for the previously enlarged brain is necessary for the language control areas to develop syntax among the aspects of organized language.
All the anatomical changes, including those in the brain, were necessary for the development of all aspects of language. Once again, the question is why, when and how the changes took place. (See below)
DAVID: You have not answered the point that H. sapiens arrived with all the required anatomical changes in place needed to produce human sounds for modern complex language which appears to have started 50,000+ years ago, 250.000 years after the first sapiens arrived. That is Mc Crone's view. Just when did your cell committees do their job?
Please tell me how McCrone knows when H. sapiens started to make the sounds needed for modern language. Did he happen to be around with his tape recorder?
Once again: I am not denying that the changed anatomy was necessary for the new sounds, but neither you nor I nor McCrone can possibly know what sounds were already being made when the anatomy reached its final form. (I propose that the final form, including that of the brain, was reached when pre-sapiens or possible early sapiens succeeded in making all the necessary changes.) As I pointed out yesterday, different modern languages have different sounds, and of course all of these are produced by the final anatomy. But the issue is what in the first place caused the changes that led to the final anatomy. Here are your choices: divine preprogramming, divine dabbling, random mutations, or cellular intelligence making changes IN RESPONSE to the need for new sounds (just like legs changing into flippers IN RESPONSE to the new environment). So please tell me which of these options McCrone favours.
Human evolution; our complex speech mechanism
by David Turell , Friday, May 10, 2019, 21:21 (2022 days ago) @ dhw
DAVID: You have not answered the point that H. sapiens arrived with all the required anatomical changes in place needed to produce human sounds for modern complex language which appears to have started 50,000+ years ago, 250.000 years after the first sapiens arrived. That is Mc Crone's view. Just when did your cell committees do their job?
dhw: Please tell me how McCrone knows when H. sapiens started to make the sounds needed for modern language. Did he happen to be around with his tape recorder?
If you read his book you would be surprised how cogent his arguments are.
dhw: Once again: I am not denying that the changed anatomy was necessary for the new sounds, but neither you nor I nor McCrone can possibly know what sounds were already being made when the anatomy reached its final form. (I propose that the final form, including that of the brain, was reached when pre-sapiens or possible early sapiens succeeded in making all the necessary changes.) As I pointed out yesterday, different modern languages have different sounds, and of course all of these are produced by the final anatomy. But the issue is what in the first place caused the changes that led to the final anatomy. Here are your choices: divine preprogramming, divine dabbling, random mutations, or cellular intelligence making changes IN RESPONSE to the need for new sounds (just like legs changing into flippers IN RESPONSE to the new environment). So please tell me which of these options McCrone favours.
What McCrone strictly presents are major anatomic and neurosensory brain control changes first and then capacity for modern language exists, defined as developing 50,000 year ago. The book is very descriptive of the changes that were required to allow what we do now. No need to describe them again, as I have done several times previously. Remember we arrived with all this stuff in place 300,000 years ago and then 250,000 years later started really complex language. You want cell committees to foresee the future: arch the palate, drop the larynx, invent an epiglottis, reroute the laryngeal nerve, alter lip and tongue muscles and tie it all into specific areas of an enlarged brain. A pipe dream. Mc Crone recognized H. erectus might have spoken, estimating 'five or six words in five seconds". (pg. 161) 'Modern man can speak at the rate of two hundred or more words per minute."
Human evolution; our complex speech mechanism
DAVID: You have not answered the point that H. sapiens arrived with all the required anatomical changes in place needed to produce human sounds for modern complex language which appears to have started 50,000+ years ago, 250.000 years after the first sapiens arrived. That is Mc Crone's view. Just when did your cell committees do their job?
dhw: Please tell me how McCrone knows when H. sapiens started to make the sounds needed for modern language. Did he happen to be around with his tape recorder?
DAVID: If you read his book you would be surprised how cogent his arguments are.
You have read it, so please tell us how he knows when H. sapiens started to make the sounds needed for modern language.
DAVID: What McCrone strictly presents are major anatomic and neurosensory brain control changes first and then capacity for modern language exists, defined as developing 50,000 year ago. […] You want cell committees to foresee the future: arch the palate, drop the larynx, invent an epiglottis, reroute the laryngeal nerve, alter lip and tongue muscles and tie it all into specific areas of an enlarged brain. A pipe dream.
I am not querying the point that these changes took place before modern language was possible. I am challenging your interpretation of how, why and when they took place. Your hypothesis has always been that your God either preprogrammed the changes or personally performed operations on existing palates, larynxes etc. Does McCrone agree? Or does he opt for random mutations? Or does he consider my proposal, which is that pre-sapiens felt the need for enhanced communication, i.e. new sounds, and the effort to produce new sounds resulted in the changes which produced the arched palate and the dropped larynx – just as the effort to swim changed pre-whale legs into flippers, and just as the illiterate women’s efforts to read changed the relevant parts of their brains. We know that brain and body make changes in response to new demands, and I keep repeating that I do NOT want cell communities to foresee the future. It is you who demand fortune-telling in the shape of your God’s plans and/or direct surgery. My proposal, once again, is that the cell communities RESPOND to needs, not that they anticipate them. What is McCrone’s proposal?
DAVID: Mc Crone recognized H. erectus might have spoken, estimating 'five or six words in five seconds". (pg. 161) 'Modern man can speak at the rate of two hundred or more words per minute."
He is welcome to his guesses, but in any case this proves nothing. Every generation builds on the progress of its predecessors. Once the anatomy was in place, of course the range of sounds, words, structures expanded. Language continues to evolve all the time. That doesn’t mean it began with a divine programme or specialist surgery to create arched palates and dropped larynxes!
Human evolution; our complex speech mechanism
by David Turell , Saturday, May 11, 2019, 20:29 (2021 days ago) @ dhw
DAVID: You have not answered the point that H. sapiens arrived with all the required anatomical changes in place needed to produce human sounds for modern complex language which appears to have started 50,000+ years ago, 250.000 years after the first sapiens arrived. That is Mc Crone's view. Just when did your cell committees do their job?
dhw: Please tell me how McCrone knows when H. sapiens started to make the sounds needed for modern language. Did he happen to be around with his tape recorder?
DAVID: If you read his book you would be surprised how cogent his arguments are.
dhw: You have read it, so please tell us how he knows when H. sapiens started to make the sounds needed for modern language.
No one knows. But it is apparent sapiens arrived with full complex language ability 300,000+ years ago and eventually learned how to use it.
DAVID: What McCrone strictly presents are major anatomic and neurosensory brain control changes first and then capacity for modern language exists, defined as developing 50,000 year ago. […] You want cell committees to foresee the future: arch the palate, drop the larynx, invent an epiglottis, reroute the laryngeal nerve, alter lip and tongue muscles and tie it all into specific areas of an enlarged brain. A pipe dream.dhw: I am not querying the point that these changes took place before modern language was possible. I am challenging your interpretation of how, why and when they took place. Your hypothesis has always been that your God either preprogrammed the changes or personally performed operations on existing palates, larynxes etc. Does McCrone agree? Or does he opt for random mutations? Or does he consider my proposal, which is that pre-sapiens felt the need for enhanced communication, i.e. new sounds, and the effort to produce new sounds resulted in the changes which produced the arched palate and the dropped larynx – just as the effort to swim changed pre-whale legs into flippers, and just as the illiterate women’s efforts to read changed the relevant parts of their brains. We know that brain and body make changes in response to new demands, and I keep repeating that I do NOT want cell communities to foresee the future. It is you who demand fortune-telling in the shape of your God’s plans and/or direct surgery. My proposal, once again, is that the cell communities RESPOND to needs, not that they anticipate them. What is McCrone’s proposal?
McCrone does not discuss the genetic possibilities we discuss. He simply describes the anatomic changes that homo fossils tell us.
DAVID: Mc Crone recognized H. erectus might have spoken, estimating 'five or six words in five seconds". (pg. 161) 'Modern man can speak at the rate of two hundred or more words per minute."dhw: He is welcome to his guesses, but in any case this proves nothing. Every generation builds on the progress of its predecessors. Once the anatomy was in place, of course the range of sounds, words, structures expanded. Language continues to evolve all the time. That doesn’t mean it began with a divine programme or specialist surgery to create arched palates and dropped larynxes!
The dropped larynx allows for our ability to speak as we do. Chimps have a simple epiglottis and an oral pharyngeal anatomy that allows for breathing and swallowing at the same time. Human infants are born with the same arrangement, and as they develop, the larynx drops and the epiglottis develops fully. This article explains:
https://mosesappliances.com/wp-content/uploads/2019/01/Evolution-of-the-Human-Oral-Airw...
I interpret it as pre-planning. You don't. That is a gulf which will never shrink.
Human evolution; our complex speech mechanism
dhw: Please tell me how McCrone knows when H. sapiens started to make the sounds needed for modern language. Did he happen to be around with his tape recorder?
DAVID: If you read his book you would be surprised how cogent his arguments are.
dhw: You have read it, so please tell us how he knows when H. sapiens started to make the sounds needed for modern language.
DAVID: No one knows. But it is apparent sapiens arrived with full complex language ability 300,000+ years ago and eventually learned how to use it.
No one knows. Thank you. Yes, we sapiens arrived with the mechanisms that enabled us to develop language, walk upright on the ground, give birth to our young through a different shaped birth canal, twiddle our thumbs, and do everything else that distinguishes us from our ancestors. The question is how, when and why all these changes took place. You say your God programmed the first cells with each and every one of them 3.8 billion years ago or they were the result of direct surgery (dabbling). I propose that each one was a response by the cellular communities to new requirements – either for survival or for improvement. Some people think it was all the result of random mutations. No one knows.
dhw: We know that brain and body make changes in response to new demands, and I keep repeating that I do NOT want cell communities to foresee the future. It is you who demand fortune-telling in the shape of your God’s plans and/or direct surgery. My proposal, once again, is that the cell communities RESPOND to needs, not that they anticipate them. What is McCrone’s proposal?
DAVID: McCrone does not discuss the genetic possibilities we discuss. He simply describes the anatomic changes that homo fossils tell us.
Then please stop using him as if he supported your hypothesis. The fossils tell us the changes that took place – not how, when or why.
DAVID: The dropped larynx allows for our ability to speak as we do. Chimps have a simple epiglottis and an oral pharyngeal anatomy that allows for breathing and swallowing at the same time. Human infants are born with the same arrangement, and as they develop, the larynx drops and the epiglottis develops fully. This article explains:
https://mosesappliances.com/wp-content/uploads/2019/01/Evolution-of-the-Human-Oral-Airw...
I interpret it as pre-planning. You don't. That is a gulf which will never shrink.
Yes, we know the changes, and it is interesting to see that infants repeat the same evolutionary process, and yes, once again you interpret this as evidence that your God provided the first living cells with a larynx-dropping, epiglottis-forming programme (along with programmes for every other change in the history of evolution), or stepped in to operate on our ancestors. You prefer to gloss over the unlikelihood of such a process with the term “pre-planning”.
Human evolution; our complex speech mechanism
by David Turell , Sunday, May 12, 2019, 20:01 (2020 days ago) @ dhw
edited by David Turell, Sunday, May 12, 2019, 20:18
dhw: We know that brain and body make changes in response to new demands, and I keep repeating that I do NOT want cell communities to foresee the future. It is you who demand fortune-telling in the shape of your God’s plans and/or direct surgery. My proposal, once again, is that the cell communities RESPOND to needs, not that they anticipate them. What is McCrone’s proposal?
DAVID: McCrone does not discuss the genetic possibilities we discuss. He simply describes the anatomic changes that homo fossils tell us.
dhw: Then please stop using him as if he supported your hypothesis. The fossils tell us the changes that took place – not how, when or why.
But his description of the changes and when they occurred fits my theory. As for your 'fortune-testing'. comment, I'll remind you the dropped larynx required intense re-engineering of the epiglottis, in anticipation of the problems related to that change, I can easily image your cell committees around the planning table puzzling what to do. Your improbable theory stretching the known fact that individual cells make intelligent appearing responses to simple stimuli is just that, an enormous stretch, when it is obviously not known/proven that cells are innately intelligent.
DAVID: The dropped larynx allows for our ability to speak as we do. Chimps have a simple epiglottis and an oral pharyngeal anatomy that allows for breathing and swallowing at the same time. Human infants are born with the same arrangement, and as they develop, the larynx drops and the epiglottis develops fully. This article explains:
https://mosesappliances.com/wp-content/uploads/2019/01/Evolution-of-the-Human-Oral-Airw...
I interpret it as pre-planning. You don't. That is a gulf which will never shrink.dhw: Yes, we know the changes, and it is interesting to see that infants repeat the same evolutionary process, and yes, once again you interpret this as evidence that your God provided the first living cells with a larynx-dropping, epiglottis-forming programme (along with programmes for every other change in the history of evolution), or stepped in to operate on our ancestors. You prefer to gloss over the unlikelihood of such a process with the term “pre-planning”.
I gloss over nothing. You always forget I've got God in charge and I have made assumptions as to how He managed control. At least I don't imagine brilliant cells running the show, as a huge imaginary stretch..
Human evolution; our complex speech mechanism
dhw: We know that brain and body make changes in response to new demands, and I keep repeating that I do NOT want cell communities to foresee the future. It is you who demand fortune-telling in the shape of your God’s plans and/or direct surgery. My proposal, once again, is that the cell communities RESPOND to needs, not that they anticipate them. What is McCrone’s proposal?
DAVID: McCrone does not discuss the genetic possibilities we discuss. He simply describes the anatomic changes that homo fossils tell us.
dhw: Then please stop using him as if he supported your hypothesis. The fossils tell us the changes that took place – not how, when or why.
DAVID: But his description of the changes and when they occurred fits my theory. As for your 'fortune-testing'. comment, I'll remind you the dropped larynx required intense re-engineering of the epiglottis, in anticipation of the problems related to that change…
And in turn I’ll remind you that in my view the re-engineering of all parts is the RESPONSE to the problems raised by the need for change (i.e. for enhanced communication through new sounds), not in anticipation of them. The sounds cannot be made without all parts cooperating – and that also includes changes to the brain. You opt for a 3.8-billion-year old computer programme or divine surgery for epiglottis re-engineering and larynx-dropping, whereas I propose that the efforts to produce new sounds caused all the changes. Clearly McCrone has nothing to say about either hypothesis, so he offers no more support to you than he does to me.
DAVID: I can easily image your cell committees around the planning table puzzling what to do.
For the thousandth time, there is no planning table in my hypothesis. My proposal is that the changes are the RESULT of efforts to produce new sounds – just as the change of legs to flippers RESULTS from efforts to implement new tasks.
DAVID: Your improbable theory stretching the known fact that individual cells make intelligent appearing responses to simple stimuli is just that, an enormous stretch, when it is obviously not known/proven that cells are innately intelligent.
For the thousandth time, none of the hypotheses are proven. But many scientists support the view that cells are innately intelligent, so it is a hypothesis to be taken seriously. How many scientists support your “assumptions” repeated below?
DAVID: You always forget I've got God in charge and I have made assumptions as to how He managed control. At least I don't imagine brilliant cells running the show, as a huge imaginary stretch.
I can hardly forget your assumption that 3.8 billion years ago your God provided the first cells with a programme to be passed on for every undabbled innovation, life form, lifestyle and natural wonder in the history of life. That is the basis of this whole discussion! I don’t know why you should consider this hypothesis to be more imaginable than your God designing microorganisms with the intelligence to cooperate in forming an ever increasing variety of cell communities.
Human evolution; our complex speech mechanism
by David Turell , Monday, May 13, 2019, 17:16 (2019 days ago) @ dhw
dhw: Then please stop using him as if he supported your hypothesis. The fossils tell us the changes that took place – not how, when or why.
But McCrone specifically states the fossils show the changes were present in habilis and the erectus well before modern speech appeared. Do you read what I stated? When is not in question
DAVID: But his description of the changes and when they occurred fits my theory. As for your 'fortune-testing'. comment, I'll remind you the dropped larynx required intense re-engineering of the epiglottis, in anticipation of the problems related to that change…
dhw: And in turn I’ll remind you that in my view the re-engineering of all parts is the RESPONSE to the problems raised by the need for change (i.e. for enhanced communication through new sounds), not in anticipation of them. The sounds cannot be made without all parts cooperating – and that also includes changes to the brain. You opt for a 3.8-billion-year old computer programme or divine surgery for epiglottis re-engineering and larynx-dropping, whereas I propose that the efforts to produce new sounds caused all the changes. Clearly McCrone has nothing to say about either hypothesis, so he offers no more support to you than he does to me.
You are still ignoring my statements summarizing McCrone.
DAVID: I can easily image your cell committees around the planning table puzzling what to do.dhw: For the thousandth time, there is no planning table in my hypothesis. My proposal is that the changes are the RESULT of efforts to produce new sounds – just as the change of legs to flippers RESULTS from efforts to implement new tasks.
And I find your hypothesis impossible, as all the different changes have to coordinated. Even Dawkins says biology looks designed.
DAVID: Your improbable theory stretching the known fact that individual cells make intelligent appearing responses to simple stimuli is just that, an enormous stretch, when it is obviously not known/proven that cells are innately intelligent.dhw: For the thousandth time, none of the hypotheses are proven. But many scientists support the view that cells are innately intelligent, so it is a hypothesis to be taken seriously. How many scientists support your “assumptions” repeated below?
DAVID: You always forget I've got God in charge and I have made assumptions as to how He managed control. At least I don't imagine brilliant cells running the show, as a huge imaginary stretch.
dhw: I can hardly forget your assumption that 3.8 billion years ago your God provided the first cells with a programme to be passed on for every undabbled innovation, life form, lifestyle and natural wonder in the history of life. That is the basis of this whole discussion! I don’t know why you should consider this hypothesis to be more imaginable than your God designing microorganisms with the intelligence to cooperate in forming an ever increasing variety of cell communities.
See my new entry on Darwin doubt among scientists. And I'll remind you, I view God as much more purposeful than you do. He won't give up tight control over evolution.
Human evolution; our complex speech mechanism
dhw: Then please stop using him [McCrone] as if he supported your hypothesis. The fossils tell us the changes that took place – not how, when or why.
DAVID: But McCrone specifically states the fossils show the changes were present in habilis and the erectus well before modern speech appeared. Do you read what I stated? When is not in question
Thank you. I rely on you to inform me about McCrone’s findings and arguments. If all the changes were present in habilis and erectus, does he think they communicated without using their voices to make sounds, and how does he know that they were not able to make some of the sounds that are now used in modern speech? Is there a tape recording?
DAVID: I'll remind you the dropped larynx required intense re-engineering of the epiglottis, in anticipation of the problems related to that change…
dhw: And in turn I’ll remind you that in my view the re-engineering of all parts is the RESPONSE to the problems raised by the need for change (i.e. for enhanced communication through new sounds), not in anticipation of them. The sounds cannot be made without all parts cooperating – and that also includes changes to the brain. You opt for a 3.8-billion-year old computer programme or divine surgery for epiglottis re-engineering and larynx-dropping, whereas I propose that the efforts to produce new sounds caused all the changes. Clearly McCrone has nothing to say about either hypothesis, so he offers no more support to you than he does to me.
DAVID: You are still ignoring my statements summarizing McCrone.
You told us that he has nothing to say about how the changes took place. If so, what statements have you summarized in support of your preprogramming/dabbling hypothesis?
DAVID: I can easily image your cell committees around the planning table puzzling what to do.
dhw: For the thousandth time, there is no planning table in my hypothesis. My proposal is that the changes are the RESULT of efforts to produce new sounds – just as the change of legs to flippers RESULTS from efforts to implement new tasks.
DAVID: And I find your hypothesis impossible, as all the different changes have to coordinated. Even Dawkins says biology looks designed.
I wrote above (now bolded) that all parts have to cooperate, and I have always agreed that biology looks designed. In case you’ve forgotten, my theistic proposal is that your God designed the mechanism that does the designing – as opposed to preprogramming the first cells with every single undabbled design in the history of life.
DAVID: See my new entry on Darwin doubt among scientists. And I'll remind you, I view God as much more purposeful than you do. He won't give up tight control over evolution.
See my reply on the Darwin thread, and I do not accept that your view of God is “much more purposeful”, since the only purpose you are prepared to offer for every organism that ever existed is his wish to design H. sapiens. You have no justification for claiming that “he won’t give up tight control”, especially since your belief in tight control leaves you with “no idea” why he chose the above method to fulfil his one and only purpose. It is perfectly feasible that his purpose was to create the ongoing, ever-changing spectacle of life’s history, with humans providing the richest variety of all. Your God as spectator at his own production instead of puppet master (but always with the option of dabbling when he feels like it).
Human evolution; our complex speech mechanism
by David Turell , Tuesday, May 14, 2019, 14:59 (2018 days ago) @ dhw
dhw: Thank you. I rely on you to inform me about McCrone’s findings and arguments. If all the changes were present in habilis and erectus, does he think they communicated without using their voices to make sounds, and how does he know that they were not able to make some of the sounds that are now used in modern speech? Is there a tape recording?
DAVID: And I find your hypothesis impossible, as all the different changes have to coordinated. Even Dawkins says biology looks designed.
dhw: I wrote above (now bolded) that all parts have to cooperate, and I have always agreed that biology looks designed. In case you’ve forgotten, my theistic proposal is that your God designed the mechanism that does the designing – as opposed to preprogramming the first cells with every single undabbled design in the history of life.
And I've written such a mechanism must contain God's guidelines, and you have refused to accept that limitation which means your mechanism allows that God is not entirely in control
DAVID: See my new entry on Darwin doubt among scientists. And I'll remind you, I view God as much more purposeful than you do. He won't give up tight control over evolution.dhw: See my reply on the Darwin thread, and I do not accept that your view of God is “much more purposeful”, since the only purpose you are prepared to offer for every organism that ever existed is his wish to design H. sapiens. You have no justification for claiming that “he won’t give up tight control”, especially since your belief in tight control leaves you with “no idea” why he chose the above method to fulfil his one and only purpose. It is perfectly feasible that his purpose was to create the ongoing, ever-changing spectacle of life’s history, with humans providing the richest variety of all. Your God as spectator at his own production instead of puppet master (but always with the option of dabbling when he feels like it).
Same old mantra. I accept th at God chose the method He did. You can't refute that point, so you keep repeating I have 'no idea', but I do.
Human evolution; our complex speech mechanism
dhw: I rely on you to inform me about McCrone’s findings and arguments. If all the changes were present in habilis and erectus, does he think they communicated without using their voices to make sounds, and how does he know that they were not able to make some of the sounds that are now used in modern speech? Is there a tape recording?
I notice you have skipped over this point. Please tell us how McCrone knows that pre-sapiens did not use his larynx and epiglottis to make sounds now made by H. sapiens.
DAVID: And I find your hypothesis impossible, as all the different changes have to coordinated. Even Dawkins says biology looks designed.
dhw: I wrote above […] that all parts have to cooperate, and I have always agreed that biology looks designed. In case you’ve forgotten, my theistic proposal is that your God designed the mechanism that does the designing – as opposed to preprogramming the first cells with every single undabbled design in the history of life.
DAVID: And I've written such a mechanism must contain God's guidelines, and you have refused to accept that limitation which means your mechanism allows that God is not entirely in control.
The only “guidelines” you can offer are a 3.8-billion-year-old computer programme for epiglottises and larynxes and every other evolutionary change in life’s history, or your God performing ad hoc operations on individual organisms. Yes, in my theistic hypothesis, my autonomous mechanism means God deliberately creates a free-for-all while still having the option to dabble if he feels like it. How do you know your God does not want some unpredictability to add to the interest?
DAVID: […] I'll remind you, I view God as much more purposeful than you do. He won't give up tight control over evolution.
dhw: […] I do not accept that your view of God is “much more purposeful”, since the only purpose you are prepared to offer for every organism that ever existed is his wish to design H. sapiens. You have no justification for claiming that “he won’t give up tight control”, especially since your belief in tight control leaves you with “no idea” why he chose the above method to fulfil his one and only purpose. It is perfectly feasible that his purpose was to create the ongoing, ever-changing spectacle of life’s history, with humans providing the richest variety of all. Your God as spectator at his own production instead of puppet master (but always with the option of dabbling when he feels like it).
DAVID: Same old mantra. I accept that God chose the method He did. You can't refute that point, so you keep repeating I have 'no idea', but I do.
In your own words, you have “no idea why God chose to evolve humans over time”. We agree that if God exists, he chose evolution to fulfil his purposes. That is a million miles away from saying that he chose your interpretation of evolution (every life form etc. specially preprogrammed or dabbled) to fulfil your interpretation of his purpose (to specially design humans). See "Unanswered questions" for your concept of evolution which so blatantly contradicts your concept of your God's purpose.
Human evolution; our complex speech mechanism
by David Turell , Wednesday, May 15, 2019, 18:07 (2017 days ago) @ dhw
dhw: I rely on you to inform me about McCrone’s findings and arguments. If all the changes were present in habilis and erectus, does he think they communicated without using their voices to make sounds, and how does he know that they were not able to make some of the sounds that are now used in modern speech? Is there a tape recording?
I notice you have skipped over this point. Please tell us how McCrone knows that pre-sapiens did not use his larynx and epiglottis to make sounds now made by H. sapiens.
I said Mc Crone did describe them talking at five, six words per minute, remember?
DAVID: And I've written such a mechanism must contain God's guidelines, and you have refused to accept that limitation which means your mechanism allows that God is not entirely in control.dhw: The only “guidelines” you can offer are a 3.8-billion-year-old computer programme for epiglottises and larynxes and every other evolutionary change in life’s history, or your God performing ad hoc operations on individual organisms. Yes, in my theistic hypothesis, my autonomous mechanism means God deliberately creates a free-for-all while still having the option to dabble if he feels like it. How do you know your God does not want some unpredictability to add to the interest?
As usual I think your concept humanizes God. I view Him as knowing exactly what He wants
DAVID: Same old mantra. I accept that God chose the method He did. You can't refute that point, so you keep repeating I have 'no idea', but I do.dhw: In your own words, you have “no idea why God chose to evolve humans over time”. We agree that if God exists, he chose evolution to fulfil his purposes. That is a million miles away from saying that he chose your interpretation of evolution (every life form etc. specially preprogrammed or dabbled) to fulfil your interpretation of his purpose (to specially design humans). See "Unanswered questions" for your concept of evolution which so blatantly contradicts your concept of your God's purpose.
What is evolution but the development of all the forms that evolution has produced? If God is in change, the history of what He did is clear. And humans are certainly specially designed, compared to everything else
Human evolution; split from Neanderthals
by David Turell , Thursday, May 16, 2019, 01:07 (2016 days ago) @ David Turell
About 800,000 years ago:
https://cosmosmagazine.com/palaeontology/neanderthals-and-modern-humans-parted-company-...
"Now a new study, centring on hominin remains found in a Spanish cave, push the likely diversion date back even further, to around 800,000 years ago.
***
"Gómez-Robles’s approach took advantage of the fact that while tooth sizes vary quite broadly within hominin species, tooth shape, at least in the matter of molars, tends to be much more homogenous, and changes only slowly.
"She took a very close look at the teeth of some of the 28 sets of hominin remains discovered in a cave known Sima de los Huesos (SH), in Spain – a site that has been subject to continual exploration since it was first discovered in 1984.
" Establishing the age of the Spanish remains was for many years a controversial process, but a 2014 study employing luminescence dating techniques and palaeomagnetism conclusively established that the cave occupants lived about 430,000 years ago.
"The date, for Gómez-Robles, was highly significant. Analysis of the hominins’ teeth revealed that they were “unexpectedly derived toward the Neanderthal condition”.
"It followed, therefore, that the Sima de los Huesos hominins must have existed after the last common ancestor of Neanderthals and modern humans.
"Not only that, Gómez-Robles writes, they must have lived substantially after the divergence, unless they were, at least in the matter of dentition, for some reason subject to “exceedingly high evolutionary rates”.
***
"However, she concludes, “the simplest explanation of the results presented in this study is that Neanderthals and modern humans diverged before [800,000 years ago], which would make evolutionary rates for the SH dentition roughly comparable to those found in other species.”
"The findings are unlikely to settle the divergence debate once and for all, particularly as they sit at odds with DNA-based dating attempts. Gómez-Robles fully acknowledges this state of affairs, and suggests that much more research is necessary – and many more fossils need to be found – before the matter can be resolved.
“'The discrepancies between the dates at which clear Neanderthal and modern human affinities are observed in the hominin fossil record may seem to indicate differential evolutionary rates in both lineages, which would affect the inferences made through the present study,” she notes.
“'However, they may simply reflect the incompleteness of the fossil record, particularly for the modern human lineage.'”
Comment: We had to split at some point.
Human evolution; our complex speech mechanism
dhw: I rely on you to inform me about McCrone’s findings and arguments. If all the changes were present in habilis and erectus, does he think they communicated without using their voices to make sounds, and how does he know that they were not able to make some of the sounds that are now used in modern speech? Is there a tape recording?
I notice you have skipped over this point. Please tell us how McCrone knows that pre-sapiens did not use his larynx and epiglottis to make sounds now made by H. sapiens.
DAVID: I said McCrone did describe them talking at five, six words per minute, remember?
And how does he know that? Anyway, the argument now is that the mechanisms for modern language were already in place and were already being used before H. sapiens. There is therefore no gulf between pre-sapiens and sapiens, but simply an onward development of sounds as pre-sapiens and sapiens built on the linguistic achievements of their predecessors. Please explain what you think this proves.
DAVID: And I've written such a mechanism must contain God's guidelines, and you have refused to accept that limitation which means your mechanism allows that God is not entirely in control.
dhw: The only “guidelines” you can offer are a 3.8-billion-year-old computer programme for epiglottises and larynxes and every other evolutionary change in life’s history, or your God performing ad hoc operations on individual organisms. Yes, in my theistic hypothesis, my autonomous mechanism means God deliberately creates a free-for-all while still having the option to dabble if he feels like it. How do you know your God does not want some unpredictability to add to the interest?
DAVID: As usual I think your concept humanizes God. I view Him as knowing exactly what He wants.
If he exists, I also view him as knowing exactly what he wants, and it ain’t the same as your version of exactly what he wants. And there is no point in talking about purpose if you are not prepared to tell us what that purpose is. AnD why do you think your God is incapable of creating an autonomous mechanism, as opposed to a mechanism that preprogrammes every undabbled change in the history of evolution?
DAVID: What is evolution but the development of all the forms that evolution has produced? If God is in change, the history of what He did is clear. And humans are certainly specially designed, compared to everything else.
Yes, evolution is the history of all the forms, and if God exists, that history is clear. But you keep telling us that EVERYTHING is specially designed – even the weaverbird’s nest – and THAT is the problem with your hypothesis, because you will insist that he specially designed EVERY form, and did so only in order to specially design humans.
Human evolution; our complex speech mechanism
by David Turell , Thursday, May 16, 2019, 18:48 (2016 days ago) @ dhw
DAVID: I said McCrone did describe them talking at five, six words per minute, remember?
dhw: And how does he know that? Anyway, the argument now is that the mechanisms for modern language were already in place and were already being used before H. sapiens. There is therefore no gulf between pre-sapiens and sapiens, but simply an onward development of sounds as pre-sapiens and sapiens built on the linguistic achievements of their predecessors. Please explain what you think this proves.
The physical changes advanced with each homo stage including humans, but really functional language appeared 50,000 years ago perv theory. Form appeared before true function. Tht is what it proves. Design first.
DAVID: As usual I think your concept humanizes God. I view Him as knowing exactly what He wants.dhw: If he exists, I also view him as knowing exactly what he wants, and it ain’t the same as your version of exactly what he wants. And there is no point in talking about purpose if you are not prepared to tell us what that purpose is. AnD why do you think your God is incapable of creating an autonomous mechanism, as opposed to a mechanism that preprogrammes every undabbled change in the history of evolution?
your view is very different than mine in which I see Him as purely purposeful, who does not need spectacle
DAVID: What is evolution but the development of all the forms that evolution has produced? If God is in change, the history of what He did is clear. And humans are certainly specially designed, compared to everything else.dhw: Yes, evolution is the history of all the forms, and if God exists, that history is clear. But you keep telling us that EVERYTHING is specially designed – even the weaverbird’s nest – and THAT is the problem with your hypothesis, because you will insist that he specially designed EVERY form, and did so only in order to specially design humans.
And just why can't it be proposed that He designed everything, while in charge of evolution?
Human evolution; our complex speech mechanism
DAVID: I said McCrone did describe them talking at five, six words per minute, remember?
dhw: And how does he know that? Anyway, the argument now is that the mechanisms for modern language were already in place and were already being used before H. sapiens. There is therefore no gulf between pre-sapiens and sapiens, but simply an onward development of sounds as pre-sapiens and sapiens built on the linguistic achievements of their predecessors. Please explain what you think this proves.
DAVID: The physical changes advanced with each homo stage including humans, but really functional language appeared 50,000 years ago perv theory. Form appeared before true function. That is what it proves. Design first.
What do you mean by “really functional language” and “true function”? Do you honestly think that communication between pre-sapiens and between early sapiens didn’t function? Nobody can possibly know how simple/complex early language was unless they were standing around with a tape recorder. Language must have evolved from simple beginnings to its current complexities as homos and humans built on the linguistic inventions of their predecessors in response to the need for a wider range of communication. But there would certainly have been long periods of linguistic stasis in times when societies themselves were static.
DAVID: As usual I think your concept humanizes God. I view Him as knowing exactly what He wants.
dhw: If he exists, I also view him as knowing exactly what he wants, and it ain’t the same as your version of exactly what he wants. And there is no point in talking about purpose if you are not prepared to tell us what that purpose is. AnD why do you think your God is incapable of creating an autonomous mechanism, as opposed to a mechanism that preprogrammes every undabbled change in the history of evolution?
DAVID: your view is very different than mine in which I see Him as purely purposeful, who
does not need spectacle
What do you mean by “purely purposeful”? How can you have a purpose without a definition of what that purpose is? You are playing with words. And you haven’t explained why you think your God is incapable of creating an autonomous mechanism.
DAVID: What is evolution but the development of all the forms that evolution has produced? If God is in change, the history of what He did is clear. And humans are certainly specially designed, compared to everything else.
dhw: Yes, evolution is the history of all the forms, and if God exists, that history is clear. But you keep telling us that EVERYTHING is specially designed – even the weaverbird’s nest – and THAT is the problem with your hypothesis, because you will insist that he specially designed EVERY form, and did so only in order to specially design humans.
DAVID: And just why can't it be proposed that He designed everything, while in charge of evolution?
Of course it can be proposed. It simply doesn’t make sense that he should specially design the whale’s flipper and the weaverbird’s nest when the only thing he wanted to design was H. sapiens.
Human evolution; our complex speech mechanism
by David Turell , Friday, May 17, 2019, 18:52 (2015 days ago) @ dhw
DAVID: The physical changes advanced with each homo stage including humans, but really functional language appeared 50,000 years ago perv theory. Form appeared before true function. That is what it proves. Design first.
dhw: What do you mean by “really functional language” and “true function”? Do you honestly think that communication between pre-sapiens and between early sapiens didn’t function? Nobody can possibly know how simple/complex early language was unless they were standing around with a tape recorder. Language must have evolved from simple beginnings to its current complexities as homos and humans built on the linguistic inventions of their predecessors in response to the need for a wider range of communication. But there would certainly have been long periods of linguistic stasis in times when societies themselves were static.
"Really functional language" and "true function" are meant to describe our speech ability starting 50,000 years ago. After your quibbling, the rest of your statement recognizes the progression of language after being give the anatomic mechanisms by phenotypic evolution. You cannot deny that, much as you would like to.
DAVID: your view is very different than mine in which I see Him as purely purposeful, who does not need spectacledhw; What do you mean by “purely purposeful”? How can you have a purpose without a definition of what that purpose is? You are playing with words. And you haven’t explained why you think your God is incapable of creating an autonomous mechanism.
You are twisting interpretations as usual. You know full well, I view God as much more serious than you do. Of course I've said, God is capable of inventing an autonomous mechanism. My objection to your proposal again returns to our individual concepts of who God is and what He controls from His desires.
DAVID: What is evolution but the development of all the forms that evolution has produced? If God is in change, the history of what He did is clear. And humans are certainly specially designed, compared to everything else.dhw: Yes, evolution is the history of all the forms, and if God exists, that history is clear. But you keep telling us that EVERYTHING is specially designed – even the weaverbird’s nest – and THAT is the problem with your hypothesis, because you will insist that he specially designed EVERY form, and did so only in order to specially design humans.
DAVID: And just why can't it be proposed that He designed everything, while in charge of evolution?
dhw: Of course it can be proposed. It simply doesn’t make sense that he should specially design the whale’s flipper and the weaverbird’s nest when the only thing he wanted to design was H. sapiens.
Again a huge hole in your reasoning. Accepting that God is in charge of design within the process of evolution, what you say He should not do, is exactly what He had to do to eventually create humans by evolving them from previous forms. Obviously, we concptualize God very differently. Thus your problem with my view
Human evolution; balanced diet 120,000 years ago
by David Turell , Friday, May 17, 2019, 21:20 (2015 days ago) @ David Turell
From a cave in South Africa:
https://phys.org/news/2019-05-earliest-evidence-cooking-starch.html
"New discoveries made at the Klasies River Cave in South Africa's southern Cape, where charred food remains from hearths were found, provide the first archaeological evidence that anatomically modern humans were roasting and eating plant starches, such as those from tubers and rhizomes, as early as 120,000 years ago.
"The new research by an international team of archaeologists, published in the Journal of Human Evolution, provides archaeological evidence that has previously been lacking to support the hypothesis that the duplication of the starch digestion genes is an adaptive response to an increased starch diet.
***
"'Our results showed that these small ashy hearths were used for cooking food and starchy roots and tubers were clearly part of their diet, from the earliest levels at around 120,000 years ago through to 65,000 years ago," says Larbey. "Despite changes in hunting strategies and stone tool technologies, they were still cooking roots and tubers."
"Professor Sarah Wurz from the School of Geography, Archaeology and Environmental Studies at the University of the Witwatersrand in Johannesburg, South Africa (Wits University) and principal investigator of the site says the research shows that "early human beings followed a balanced diet and that they were ecological geniuses, able to exploit their environments intelligently for suitable foods and perhaps medicines".
"By combining cooked roots and tubers as a staple with protein and fats from shellfish, fish, small and large fauna, these communities were able to optimally adapt to their environment, indicating great ecological intelligence as early as 120,000 years ago.
"'Starch diet isn't something that happens when we started farming, but rather, is as old as humans themselves," says Larbey. Farming in Africa only started in the last 10,000 years of human existence.
***
"'Evidence from Klasies River, where several human skull fragments and two maxillary fragments dating 120,000 years ago occur, show that humans living in that time period looked like modern humans of today. However, they were somewhat more robust," says Wurz."
Comment: We adapted to starches, just like adults adapted to milk when dairy herds were developed. And I'm sure these folks had rudimentary language.
Human evolution; our complex speech mechanism
DAVID: The physical changes advanced with each homo stage including humans, but really functional language appeared 50,000 years ago perv theory. Form appeared before true function. That is what it proves. Design first.
dhw: What do you mean by “really functional language” and “true function”? Do you honestly think that communication between pre-sapiens and between early sapiens didn’t function? Nobody can possibly know how simple/complex early language was unless they were standing around with a tape recorder. Language must have evolved from simple beginnings to its current complexities as homos and humans built on the linguistic inventions of their predecessors in response to the need for a wider range of communication. But there would certainly have been long periods of linguistic stasis in times when societies themselves were static.
DAVID: "Really functional language" and "true function" are meant to describe our speech ability starting 50,000 years ago.
I wish you would make up your mind. According to you and apparently McCrone, all the necessary anatomical changes (i.e. the ability to speak) were already in place, even in our immediate predecessors, but by some mysterious means, he happens to know that they only spoke five or six words a minute. Apparently this did not enable them to use language functionally. Also by some mysterious means he happens to know that they started gabbling away 50,000 years ago. If this is true, there must have been a leap forward in the requirements for an expanded range of vocabulary.
DAVID: After your quibbling, the rest of your statement recognizes the progression of language after being give the anatomic mechanisms by phenotypic evolution. You cannot deny that, much as you would like to.
I am not denying it at all. My proposal all along has been that the changes in the anatomic mechanisms (= phenotypic evolution),and hence in the ability to produce new sounds, were the RESULT of cells restructuring themselves IN RESPONSE to the need for a wider range of communication (just as pre-whale legs became flippers IN RESPONSE to a change in their environment). Not your God performing various operations on various individuals at various times. And of course language progressed once this evolutionary process had produced the new mechanisms. Where on earth have you found me denying that?
DAVID: your view is very different than mine in which I see Him as purely purposeful, who does not need spectacle
dhw: What do you mean by “purely purposeful”? How can you have a purpose without a definition of what that purpose is? You are playing with words. And you haven’t explained why you think your God is incapable of creating an autonomous mechanism.
DAVID: You are twisting interpretations as usual. You know full well, I view God as much more serious than you do. Of course I've said, God is capable of inventing an autonomous mechanism. My objection to your proposal again returns to our individual concepts of who God is and what He controls from His desires.
Why is a “pure” purpose without any substance more “serious” than a defined purpose? You are trying to present us with a God who has no feelings, no interests, no recognizably human traits. He might as well be a robot. He follows his own single command: “Thou shalt create H. Sapiens”, but for unknown reasons chooses to create H. sapiens by first creating a billion non-sapiens life forms, lifestyles and natural wonders.
DAVID: And just why can't it be proposed that He designed everything, while in charge of evolution?
dhw: Of course it can be proposed. It simply doesn’t make sense that he should specially design the whale’s flipper and the weaverbird’s nest when the only thing he wanted to design was H. sapiens.
DAVID: Again a huge hole in your reasoning. Accepting that God is in charge of design within the process of evolution, what you say He should not do, is exactly what He had to do to eventually create humans by evolving them from previous forms.
We agree that humans evolved from previous forms. But as usual you prefer to ignore the fact that (a) according to you, every stage of evolution was specially designed, and (b) he specially designed every other non-human life form extant and extinct, although the only thing he wanted to specially design was H. sapiens. And you have “no idea” why he “chose” that way to produce the only thing he wanted to produce.
Human evolution; our complex speech mechanism
by David Turell , Saturday, May 18, 2019, 19:06 (2014 days ago) @ dhw
DAVID: "Really functional language" and "true function" are meant to describe our speech ability starting 50,000 years ago.
dhw: I wish you would make up your mind. According to you and apparently McCrone, all the necessary anatomical changes (i.e. the ability to speak) were already in place, even in our immediate predecessors, but by some mysterious means, he happens to know that they only spoke five or six words a minute. Apparently this did not enable them to use language functionally.
mcCrone's description of their speaking ability is based on his knowledge of their anatomy and their presumed ability to produce bursts of air to be formed into intelligible sounds by tongue, lips and a lower larynx. Nothing mysterious. I cannot reproduce all the intelligence in the book for you, but as he presents it, it is very believable. Obviously they did have a simple language, not the sophisticated one like ours from 50,000 years ago. In an example of early language think of the evidence from the Old Testament: 2-3,000 word bases and with punctuation marks, suffixes and prefixes resulting in about 10,000 meaningful words. One can presume the spoken language was somewhat larger, and is much larger now that the Israelis have added many words from others. Last estimate I saw was 60-70,000.
dhw: Also by some mysterious means he happens to know that they started gabbling away 50,000 years ago. If this is true, there must have been a leap forward in the requirements for an expanded range of vocabulary.
Not mysterious, but based on current linguist estimates. What you fail to notice (or to stubbornly) accept is they were given the physical ability to gabble 250,000 years prior to the gabble. Form before function is the simple historical claim
DAVID: After your quibbling, the rest of your statement recognizes the progression of language after being give the anatomic mechanisms by phenotypic evolution. You cannot deny that, much as you would like to.dhw: I am not denying it at all. My proposal all along has been that the changes in the anatomic mechanisms (= phenotypic evolution),and hence in the ability to produce new sounds, were the RESULT of cells restructuring themselves IN RESPONSE to the need for a wider range of communication (just as pre-whale legs became flippers IN RESPONSE to a change in their environment). Not your God performing various operations on various individuals at various times. And of course language progressed once this evolutionary process had produced the new mechanisms. Where on earth have you found me denying that?
God did it, not your cells, which cannot design increasing complexity. Thanks for finally accepting my timeline.
DAVID: You are twisting interpretations as usual. You know full well, I view God as much more serious than you do. Of course I've said, God is capable of inventing an autonomous mechanism. My objection to your proposal again returns to our individual concepts of who God is and what He controls from His desires.dhw: Why is a “pure” purpose without any substance more “serious” than a defined purpose? You are trying to present us with a God who has no feelings, no interests, no recognizably human traits. He might as well be a robot. He follows his own single command: “Thou shalt create H. Sapiens”, but for unknown reasons chooses to create H. sapiens by first creating a billion non-sapiens life forms, lifestyles and natural wonders.
Same silly mantra: what is so hard in understanding God chose to evolve His creations? He may have 'human traits', but are unknown to us. Why guess at humanizing Him? Just follow His works!
DAVID: And just why can't it be proposed that He designed everything, while in charge of evolution?dhw: Of course it can be proposed. It simply doesn’t make sense that he should specially design the whale’s flipper and the weaverbird’s nest when the only thing he wanted to design was H. sapiens.
DAVID: Again a huge hole in your reasoning. Accepting that God is in charge of design within the process of evolution, what you say He should not do, is exactly what He had to do to eventually create humans by evolving them from previous forms.
dhw: We agree that humans evolved from previous forms. But as usual you prefer to ignore the fact that (a) according to you, every stage of evolution was specially designed, and (b) he specially designed every other non-human life form extant and extinct, although the only thing he wanted to specially design was H. sapiens. And you have “no idea” why he “chose” that way to produce the only thing he wanted to produce.
Same wildly illogical mantra. I accept that God chose to evolve everything to reach the goal of humans, rather than a direct Biblical form of creation. You want me to return to accepting the Genesis version for some really strange reasoning, which cannot be followed.
Human evolution; our complex speech mechanism
DAVID: "Really functional language" and "true function" are meant to describe our speech ability starting 50,000 years ago.
dhw: I wish you would make up your mind. According to you and apparently McCrone, all the necessary anatomical changes (i.e. the ability to speak) were already in place, even in our immediate predecessors, but by some mysterious means, he happens to know that they only spoke five or six words a minute. Apparently this did not enable them to use language functionally.
DAVID: mcCrone's description of their speaking ability is based on his knowledge of their anatomy and their presumed ability to produce bursts of air to be formed into intelligible sounds by tongue, lips and a lower larynx. Nothing mysterious. I cannot reproduce all the intelligence in the book for you, but as he presents it, it is very believable. Obviously they did have a simple language, not the sophisticated one like ours from 50,000 years ago. In an example of early language think of the evidence from the Old Testament etc.
I keep saying that language evolves! Once the anatomy was in place, then it evolved from the simple pre-sapiens through to the complex language we know today. What’s the problem?
dhw: Also by some mysterious means he happens to know that they started gabbling away 50,000 years ago. If this is true, there must have been a leap forward in the requirements for an expanded range of vocabulary.
DAVID: Not mysterious, but based on current linguist estimates. What you fail to notice (or to stubbornly) accept is they were given the physical ability to gabble 250,000 years prior to the gabble. Form before function is the simple historical claim.
That is the nature of evolution! One generation builds on the achievements of its predecessors. What is all this meant to prove? My proposal is that pre-sapiens needed a wider range of communication, and the effort to produce new sounds resulted in anatomical changes. Once the changes had taken place, the range of sounds increased in response to ever growing needs. Exactly the same process as yours, except that you think your God performed various operations on pre-sapiens to enable him to make the sounds.
DAVID: God did it, not your cells, which cannot design increasing complexity. Thanks for finally accepting my timeline.
Did you see him operating? Why should he not have given cells the ability to design increasing complexity? The time line is irrelevant. Language evolved from the simple to the more complex – probably with periods of stasis in between, when there was nothing new to communicate.
dhw: Why is a “pure” purpose without any substance more “serious” than a defined purpose? You are trying to present us with a God who has no feelings, no interests, no recognizably human traits. He might as well be a robot. He follows his own single command: “Thou shalt create H. Sapiens”, but for unknown reasons chooses to create H. sapiens by first creating a billion non-sapiens life forms, lifestyles and natural wonders.
DAVID: Same silly mantra: what is so hard in understanding God chose to evolve His creations? He may have 'human traits', but are unknown to us. Why guess at humanizing Him? Just follow His works!
And later: You want me to return to accepting the Genesis version for some really strange reasoning, which cannot be followed.
I have no problem with your God choosing to evolve his creations. The problem is that you have him specially designing EVERY creation in order to specially design us. I don’t want you to return to Genesis; I want you to explain why he specially designed the slingshot spider if his only purpose was to specially design H. sapiens. And what is the point of telling us how purposeful he is if you are not prepared to discuss his possible purposes?
Human evolution; our complex speech mechanism
by David Turell , Thursday, May 23, 2019, 19:18 (2009 days ago) @ dhw
DAVID: mcCrone's description of their speaking ability is based on his knowledge of their anatomy and their presumed ability to produce bursts of air to be formed into intelligible sounds by tongue, lips and a lower larynx. Nothing mysterious. I cannot reproduce all the intelligence in the book for you, but as he presents it, it is very believable. Obviously they did have a simple language, not the sophisticated one like ours from 50,000 years ago. In an example of early language think of the evidence from the Old Testament etc.
dhw: I keep saying that language evolves! Once the anatomy was in place, then it evolved from the simple pre-sapiens through to the complex language we know today. What’s the problem?
The problem is getting you to realize each pre-human had stepwise advances from ape throat and larynx anatomy to finally our human anatomy which allowed rapid speech, which then led us to learn to use it and develop our modern language ability , over recent history. Anatomy first, use second.
dhw: Also by some mysterious means he happens to know that they started gabbling away 50,000 years ago. If this is true, there must have been a leap forward in the requirements for an expanded range of vocabulary.DAVID: Not mysterious, but based on current linguist estimates. What you fail to notice (or to stubbornly) accept is they were given the physical ability to gabble 250,000 years prior to the gabble. Form before function is the simple historical claim.
dhw: That is the nature of evolution! One generation builds on the achievements of its predecessors. What is all this meant to prove? My proposal is that pre-sapiens needed a wider range of communication, and the effort to produce new sounds resulted in anatomical changes. Once the changes had taken place, the range of sounds increased in response to ever growing needs. Exactly the same process as yours, except that you think your God performed various operations on pre-sapiens to enable him to make the sounds.
The nuances of language phonemes required the anatomy appeared first. I'll never agree that your pre-humans efforts to communicate caused the complex anatomic and brain changes required.
DAVID: Same silly mantra: what is so hard in understanding God chose to evolve His creations? He may have 'human traits', but are unknown to us. Why guess at humanizing Him? Just follow His works!
And later: You want me to return to accepting the Genesis version for some really strange reasoning, which cannot be followed.
dhw: I have no problem with your God choosing to evolve his creations. The problem is that you have him specially designing EVERY creation in order to specially design us. I don’t want you to return to Genesis; I want you to explain why he specially designed the slingshot spider if his only purpose was to specially design H. sapiens. And what is the point of telling us how purposeful he is if you are not prepared to discuss his possible purposes?
I've discussed his possible purposes over and over. The discussions are all just logical guesswork, proving nothing. And again, if God controls evolution, then He produced everything
Human evolution; our complex speech mechanism
dhw: I keep saying that language evolves! Once the anatomy was in place, then it evolved from the simple pre-sapiens through to the complex language we know today. What’s the problem?
DAVID: The problem is getting you to realize each pre-human had stepwise advances from ape throat and larynx anatomy to finally our human anatomy which allowed rapid speech, which then led us to learn to use it and develop our modern language ability , over recent history. Anatomy first, use second.
Of course there were stepwise advances, and of course we used them to develop new sounds that have led to our modern language. The disagreement is your contention that your God specially designed (= preprogrammed or personally dabbled) each successive anatomical change, though he alone knows why he had to conduct so many different operations and specially design so many hominins and hominids and homos – let alone the billions of other life forms, natural wonders etc. – before finally specially designing his only desire, which was H. sapiens.
dhw: […] My proposal is that pre-sapiens needed a wider range of communication, and the effort to produce new sounds resulted in anatomical changes. Once the changes had taken place, the range of sounds increased in response to ever growing needs. Exactly the same process as yours, except that you think your God performed various operations on pre-sapiens to enable him to make the sounds.
DAVID: The nuances of language phonemes required the anatomy appeared first. I'll never agree that your pre-humans efforts to communicate caused the complex anatomic and brain changes required.
I know you won’t. And yet you know from modern research that the effort to implement ideas affects the structure of the brain. I suspect that most people would accept the idea that anatomical changes such as legs turning into flippers are a RESPONSE to new demands, as opposed to being the result of your God conducting an operation in anticipation of them. (You can multiply the example by thousands.) But as you keep pointing out, nothing is proven either way.
dhw: […] what is the point of telling us how purposeful he is if you are not prepared to discuss his possible purposes?
DAVID: I've discussed his possible purposes over and over. The discussions are all just logical guesswork, proving nothing. And again, if God controls evolution, then He produced everything.
All our discussions are guesswork with greater or lesser degrees of logic. Your “if” is the point at issue: maybe he deliberately set up a system whereby he sacrificed control, and allowed the environment to keep changing, and organisms to keep adapting to or exploiting the environmental changes (though also allowing himself the occasional dabble). This provides a logical explanation for slingshot spiders and whale flippers and weaverbirds’ nests, all of which according to your own guesswork were specially designed so that the organisms could eat or not eat one another until he specially designed H. sapiens.
Human evolution; our complex speech mechanism
by David Turell , Friday, May 24, 2019, 19:40 (2008 days ago) @ dhw
dhw: I keep saying that language evolves! Once the anatomy was in place, then it evolved from the simple pre-sapiens through to the complex language we know today. What’s the problem?
DAVID: The problem is getting you to realize each pre-human had stepwise advances from ape throat and larynx anatomy to finally our human anatomy which allowed rapid speech, which then led us to learn to use it and develop our modern language ability , over recent history. Anatomy first, use second.
dhw: Of course there were stepwise advances, and of course we used them to develop new sounds that have led to our modern language. The disagreement is your contention that your God specially designed (= preprogrammed or personally dabbled) each successive anatomical change, though he alone knows why he had to conduct so many different operations and specially design so many hominins and hominids and homos – let alone the billions of other life forms, natural wonders etc. – before finally specially designing his only desire, which was H. sapiens.
Same issue: God chose to evolve humans from the earliest life, which He created first.
dhw: […] My proposal is that pre-sapiens needed a wider range of communication, and the effort to produce new sounds resulted in anatomical changes. Once the changes had taken place, the range of sounds increased in response to ever growing needs. Exactly the same process as yours, except that you think your God performed various operations on pre-sapiens to enable him to make the sounds.DAVID: The nuances of language phonemes required the anatomy appeared first. I'll never agree that your pre-humans efforts to communicate caused the complex anatomic and brain changes required.
dhw: I know you won’t. And yet you know from modern research that the effort to implement ideas affects the structure of the brain. I suspect that most people would accept the idea that anatomical changes such as legs turning into flippers are a RESPONSE to new demands, as opposed to being the result of your God conducting an operation in anticipation of them. (You can multiply the example by thousands.) But as you keep pointing out, nothing is proven either way.
dhw: […] what is the point of telling us how purposeful he is if you are not prepared to discuss his possible purposes?
DAVID: I've discussed his possible purposes over and over. The discussions are all just logical guesswork, proving nothing. And again, if God controls evolution, then He produced everything.
dhw: All our discussions are guesswork with greater or lesser degrees of logic. Your “if” is the point at issue: maybe he deliberately set up a system whereby he sacrificed control, and allowed the environment to keep changing, and organisms to keep adapting to or exploiting the environmental changes (though also allowing himself the occasional dabble). This provides a logical explanation for slingshot spiders and whale flippers and weaverbirds’ nests, all of which according to your own guesswork were specially designed so that the organisms could eat or not eat one another until he specially designed H. sapiens.
Same answer: I accept that God chose to evolve everything starting after He created first life. And I believe we are the endpoint under His control.
Human evolution; we may need GI worms
by David Turell , Tuesday, May 28, 2019, 18:34 (2004 days ago) @ David Turell
An interesting comment on how we have approached our health and GI biome:
https://aeon.co/essays/gut-worms-were-once-a-cause-of-disease-now-they-are-a-cure?utm_s...
"What if our bias against a handful of helminths led us to slaughter billions of innocent and even helpful worms? Indeed, my research and the research of many others tell us that helminths are necessary for our health. A barrage of scientific evidence points toward helminths as being important regulators of immune function. Because of this, our genocidal campaign against intestinal worms apparently has a very nasty backlash that nobody saw coming. But science moves very slowly. All helminths are still labelled as parasites in textbooks, despite the fact that we now know this to be incorrect.
***
"The immune system was actually supporting rather than fighting off most of the bacteria in our body! This paradigm-shifting idea had far-reaching implications for the field of immunity. For example, the function of the vermiform (worm-like) appendix, that troublesome little structure in our gut, could now be seen clearly as a type of safe house for beneficial bacteria.
***
"These early observations led to numerous additional studies, summarised in 2004 by Rick Maizels at the University of Edinburgh, showing inverse relationships between helminths and allergies in various human populations. At the same time, Maizels also compiled an impressive list of studies using laboratory mice, showing that helminths attenuate a multiple sclerosis (MS)-like syndrome, a Type 1 diabetes-like condition, inflammatory bowel disease, gastric ulcers and allergic reactions, including allergic reactions to peanuts.
***
"My own research has shown that thousands of humans are now using intestinal worms, from a variety of sources, to effectively treat a wide range of allergic, autoimmune and digestive diseases. Based on previous studies, we were not surprised that people were having success. But we did find one puzzler: people and their doctors were reporting that helminths were helping to treat neuropsychiatric problems such as anxiety disorders and migraine headaches.
***
"The thought of actually using a helminth as a cure doesn’t seem to be under consideration, perhaps because we are locked into the view that only a drug can help us.
"But based on available evidence, we and others conclude that we don’t need to take the risky and potentially very long route of trying to make a worm-inspired drug. In fact, trying to recapitulate a complex biological relationship using a single molecule in a pill might be a lost cause. In contrast, the naturally occurring worm will apparently work just fine.
***
"The ‘poop transplant’ – officially called the faecal microbiota transplantation – now widely appreciated by medical researchers, is a truly tragic example of this problem. The transfer of faecal material from a healthy donor to an unhealthy one was shown, as long ago as 1958, to cure Clostridium difficile colitis.
***
"Reintroduction of helminths to the human body and poop transplants share several things in common. First, they involve naturally occurring organisms that are difficult to patent. With no patent, or ‘intellectual property’, the financial incentive for developing the associated therapy vanishes.
***
A second thing that helminths and poop transplants share in common is that they don’t require any of the panoply of modern molecular, genetic tools to sort out what’s going on. What was lost has been found, and now the biological system is restored. It’s easy to comprehend, akin to a vitamin, with no PhD required to grasp the picture.
***
"The lack of acceptance of proven and commonsense therapies such as faecal transplants is yet another. Failure to fund work aimed at the reintroduction of intestinal worms to alleviate inflammatory disease, despite compelling evidence from the laboratory, is another indication still. Why did we do all of those successful experiments with therapeutic helminths if nobody is going to translate them to the clinic?"
Comment: Thinking outside the box! Helminths, human round worms, may well be beneficial. Our reasoning about what evolution has produced in us is often very wrong: the appendix is not vestigial, the retina is a marvelous efficient structure, not 'backwards'. We should trust what evolution has given us. Nothing is poorly designed. Pre-modern humans obviously lived with beneficial worms. Accept it!
Human evolution; onset of bipedalism
by David Turell , Saturday, June 01, 2019, 20:51 (2000 days ago) @ David Turell
Current research:
https://www.sapiens.org/archaeology/human-bipedality/
"Fossils suggests that bipedality may have begun as early as 6 million years ago. But it was with Australopithecus, an early hominin who evolved in southern and eastern Africa between 4 and 2 million years ago, that our ancestors took their first steps as committed bipeds. Yet scientists still know little about the circumstances that led to this trait’s emergence.
"Carol Ward, a paleoanthropologist and anatomist at the University of Missouri, studies this question. A specialist in human origins, Ward has spent a number of field seasons at various paleontological sites, including at Kanapoi and Lomekwi in West Turkana, Kenya, where she and her colleagues recovered australopithecine fossils. Her latest work repurposes 3D medical-imaging technologies to compare modern primate anatomy, including soft tissues and organs, with the skeletal fossil record of ancient hominids.
"The way that humans get around the world is different from any other animal on Earth. We move around on the ground, upright on two feet, but in a unique way: with one foot after the other, holding our body fully upright in a characteristic series of motions. This is something that no other primate does, and it seems to be a behavior that was present in some of the earliest members of our branch of the family tree. It represented what was really the initial major adaptive change from any apelike creature that came before us.
***
"... the fossil record tells us that we began to walk upright on two feet maybe between 6 and 4 million years ago. Brains in early hominins really don’t start to get large until after 2 million years ago, so for the first two-thirds of human evolution, brain size change wasn’t really a major event.
"We have many apelike creatures that lived in the Miocene, between 23 and 5 million years ago. There’s nothing really like us at this time. And then there’s a gap in the fossil record, largely because of geologic happenstance, if you will. There aren’t many sites at the right time and place that have any fossils. And then all of a sudden, around 4 million years ago, we have these committed bipedal animals, and we don’t have a great fossil record of transitional forms.
That said, sometime between 7 and 4 million years ago a number of primates appear to have developed upright postures, but nothing as developed or specialized as we see later on. So we may be starting to get a little window on this time period.
***
"Taking my perspective in looking at the torso, combined with the new things we’re learning about australopithecines, we are finding out they’re not quite as chimp-like in all ways as we thought. Dipping further back in time, into the ape fossil record, we are finding out those things aren’t very much like modern chimps either. You map that onto the whole tree and apply the basic principles of parsimony (what’s the simplest way this could have happened?), and it’s really supporting the hypothesis that’s been around for a long time: that maybe we didn’t evolve from something that was just like a modern chimp or gorilla. But now we’re able to show in which ways ancient hominids might have been similar or different. And that’s going to help us get a much better picture of what the ancestral condition was that led to bipedality.
"Natural selection can only work on “last year’s model.” If you want to understand why something happened, you need to understand what happened."
Comment: It seems as if our evolution from the ape group was really very special. We are certainly not chimps. Note the late development of the larger brain as compared to the early bipedal posture. The hands for different uses preceded the brain development. Seem logical to me as God did His work.
Human evolution; onset of bipedalism
DAVID: It seems as if our evolution from the ape group was really very special. We are certainly not chimps. Note the late development of the larger brain as compared to the early bipedal posture. The hands for different uses preceded the brain development. Seem logical to me as God did His work.
And if we were able to study the evolution of whales and elephants and camels from their common ancestors, they too would be very special. No, we are not chimps or whales or elephants or camels, but you have your God specially designing every stage of their evolution too. Why should we note the late development of the larger brain? Was your God incapable, then, of accelerating the process, since according to you, the larger brain was all he wanted? I suggest the process was a natural progression as the perhaps God-given autonomous IM in all organisms responded to the changing conditions which you think may have been out of the control of your totally-in-control God.
Human evolution; onset of bipedalism
by David Turell , Sunday, June 02, 2019, 17:58 (1999 days ago) @ dhw
DAVID: It seems as if our evolution from the ape group was really very special. We are certainly not chimps. Note the late development of the larger brain as compared to the early bipedal posture. The hands for different uses preceded the brain development. Seem logical to me as God did His work.
dhw: And if we were able to study the evolution of whales and elephants and camels from their common ancestors, they too would be very special. No, we are not chimps or whales or elephants or camels, but you have your God specially designing every stage of their evolution too. Why should we note the late development of the larger brain? Was your God incapable, then, of accelerating the process, since according to you, the larger brain was all he wanted? I suggest the process was a natural progression as the perhaps God-given autonomous IM in all organisms responded to the changing conditions which you think may have been out of the control of your totally-in-control God.
As usual you have no answer for my concept that God prefers to carefully evolves what He desires to create. I use history which agrees as the basis of my thinking .
Human evolution; a new group of recent humans
by David Turell , Thursday, June 06, 2019, 23:36 (1995 days ago) @ David Turell
Found in Siberia:
https://www.newscientist.com/article/2205463-childrens-teeth-reveal-previously-unknown-...
"They analysed genetic data from 34 samples that range between 31,000 and 600 years old, from high-latitude sites across the Asian continent, from Finland to the Bering Strait. The samples include two fragmented milk teeth from the Yana River site in north-eastern Siberia, which are the oldest human remains found at these harsh northern latitudes.
***
"They found a lineage of people in the region that diverged from other populations around 38,000 years ago, which he and his colleagues have named Ancient North Siberians, that were not directly related to Native Americans. “It’s a people we didn’t know about. They died out. They have left tiny traces of DNA in contemporary Siberians but only a small trace, so that was a great surprise,” he says.
"Willerslev and his team found that these people moved further south to slightly warmer areas during the Last Glacial Maximum, from about 26,500 to 19,000 years ago. They are genetically closer to the hunter-gatherer populations in western Eurasia that those in the east.
"Another sample found near the Kolyma River in north-eastern Siberia dated to 10,000 years old, and may be from a descendant of the Ancient North Siberians. This sample is more closely related to the direct ancestor of Native Americans and to another group that lived east of the Bering Sea, which the team calls Ancient Palaeo-Siberians, who came about when East Asian people mixed with their northern neighbours, says Willerslev.
“'It was a really tough environment, but there were still at least three waves of migration,” he says. “Back then, there were large mammals – woolly mammoth, woolly rhinoceros, steppe bison – so in terms of food resources, this was a really attractive place to be. You may be freezing your butt off, but at least you’d have something to eat.'”
Comment: Obviously with migrations, there were many sub-groups of H. sapiens.
Human evolution; migration from Asia to N. America
by David Turell , Wednesday, May 20, 2020, 18:57 (1646 days ago) @ David Turell
Across an old land bridge:
https://www.sciencenews.org/article/oldest-genetic-link-asians-native-americans-siberia
"DNA gleaned from a roughly 14,000-year-old fragment of a human tooth suggests that people inhabiting a surprisingly large swath of Asia were the ancestors of the first Americans.
"This tooth, unearthed at a site just south of Lake Baikal in southern Siberia, provides the oldest known genetic link between Stone Age Asians and ancient American settlers, scientists report May 20 in Cell. Present-day Native Americans in North and South America are partly related to those early arrivals, the team says.
"Like a previously studied, nearly 10,000-year-old man in northeastern Siberia, the southern Siberian individual inherited genes from two Asian populations that contributed to the genetic makeup of Native Americans.
"Using DNA already extracted from human remains at several ancient Siberian sites, archaeogeneticist He Yu of the Max Planck Institute for the Science of Human History in Jena, Germany, and her colleagues conclude that one of those ancestral populations originated in northeastern Asia, east of Lake Baikal. The other hailed from north-central Asia, west of the lake.
"It’s unclear where and when members of those two populations met up and mingled. But mating between them produced a mix of DNA that characterized people who crossed a land bridge to what’s now Alaska perhaps 16,000 years ago or more, the researchers say."
Comment: Migrating out of Africa, modern humans did not reach the Americas until about 16,000 years ago. And yet many of the Pacific islands were fully colonized much earlier. Not Hawaii which occurred less than 3,000 years ago. Interesting that travel by sea was faster than over land. At sea you have no idea what is over the horizon, but they apparently had enough provisions to live to see new unknown islands.
Human evolution; our unique speech mechanism
by David Turell , Sunday, June 09, 2019, 02:11 (1992 days ago) @ David Turell
It exists only in us:
https://inference-review.com/article/the-siege-of-paris
The human language faculty is a species-specific property, with no known group differences and little variation. There are no significant analogues or homologues to the human language faculty in other species. The notion of a species-specific biological trait is itself unremarkable. Species-specific traits are essential to the very definition of a species, at least for multicellular animals requiring reproductive isolation, and species specificity is both widespread and expected according to conventional evolutionary theory. Still, an expectation, it is important to stress, is not yet an explanation.
Why only us? Why indeed.
***
Every human language is a finite computational system generating an infinite array of hierarchically structured expressions. This is the basic property (BP) of language. Every structured expression has a definite semantic interpretation and can be expressed by some sensory modality—speech when possible, gesture when not. The BP is best explained, we argued, as the expression of an underlying computational system,
***
In Why Only Us, we argued against the thesis that FOXP2 is the gene for language. FOXP2 functions as part of the system for externalizing language to the sensory-motor interface, and many aspects of externalization are not specific to human beings. Citing comparative avian work by Andreas Pfenning et al., we demonstrated that many of the systems for vocal learning and production must have been in place before the emergence of language.
***
Elizabeth Atkinson et al. carefully reexamined FOXP2 together with the intronic regions that might have been involved in a selective sweep. They found that human-specific DNA and amino acid variations matched those of Neanderthals or Denisovans but not other non-human primates.
***
How far back does language go? There is no evidence of significant symbolic activity before the appearance of anatomically modern humans 200 thousand years ago (kya). The South African Blombos cave site contains abstract patterns using ochre crayon on silcrete. These have been dated to approximately 80 kya. There is no doubt that these patterns, which represent the earliest known drawings, were executed by anatomically modern humans.
***
Recent genomic work has refined our claims about symbolic activity. The emergence of language occurred earlier than we thought, and certainly earlier than we suggested. The relevant research is drawn from the detailed genomic sequencing of human subpopulations, and establishes that between 200 kya and 125 kya, the San people in Southern Africa became genomically separated from other human populations. The San are alive today; their ancestors presumably shared the human language faculty. The BP must have emerged sometime between 300 and 200 kya.
***
He concludes that the language faculty emerged with Homo sapiens, or shortly thereafter, but externalization in one form or another must have been a later development, and quite possibly involved little or no evolutionary change. (mybold)
***
For all that, the chasm between phenotype, algorithm, and neural implementation remains just that—a chasm. We do not yet understand the space of algorithms that might inform, or guide, the BP....it is also true that we have no direct link between the genome and any complex phenotype—say, genes and walking. This remains one of the great scientific challenges, one more thing that we cannot yet puzzle out.
***
There is no evidence that great apes, however sophisticated, have any of the crucial distinguishing features of language and ample evidence that they do not. Claims made in favor of their semantic powers, we might observe, are wrong. Recent research reveals that the semantic properties of even the simplest words are radically different from anything in animal symbolic systems.
Comment: Note my bold. Anatomy was fully developed before sapiens speech appeared. Anatomic form first, then function. Note, one of the authors is Noam Chomsky
Human evolution; unique in the universe?
by David Turell , Tuesday, June 11, 2019, 01:02 (1990 days ago) @ David Turell
Paul Davies' new opinion:
https://cosmosmagazine.com/physics/wings-may-all-be-universal-smarts-not-so-much
"Whether we are alone in the universe is one of the oldest and deepest questions of existence. It was once the province of philosophy and religion, but Paul Davies suggests science has begun to make a contribution too.
"Although we have no clue how life began, and no way to estimate the odds, many astrobiologists believe life gets going easily on earthlike planets and so will be widespread in the universe. It is then possible that some of those planets might have evolved intelligent beings.
***
"With only one sample of life to go on, it’s hard to draw general conclusions. However, looking back at the evolution of life on Earth, some features, for example eyes and wings, have evolved independently many times, presumably because they have good survival value.
We might therefore expect alien life to possess these characteristics too. But other features, like the elephant’s trunk, seem to be baroque aberrations – the result of rare evolutionary accidents.
"When it comes to human-level intelligence, is that a wing-like or a trunk-like property? There is no agreement among scientists, but Charles Lineweaver of the Australian National University has pointed out that advanced intelligence evolved only once, in Africa, even though it could have arisen independently in several other isolated land masses, for example Australia or America.
"Moreover, dinosaurs, which famously “ruled the Earth” for 200 million years, never evolved to make tools, build cities or fly to the moon (as far as we know). These facts suggest that human-level intelligence is a rare quirk of fate rather than the inevitable product of natural selection. If that is so, it is bad news for SETI.
"Arguments about the likelihood of intelligent aliens is made murkier by disagreement concerning the nature of the evolutionary process. For some decades after the acceptance of Darwin’s theory, there was a popular belief that life on Earth gets progressively more complex over time.
"Sadly for SETI, most contemporary biologists don’t think evolution is heading anywhere in particular; there is no inbuilt biological arrow of time, they claim, no innate drive towards complexity or braininess.
"True, life on Earth started out with simple microbes, but the emergence of greater complexity was merely the product of a meandering exploration in the vast space of biological possibilities, and not a systematic trend. The idea that intelligence is somehow “waiting in the wings” for a chance to arise is dismissed as mystical nonsense.
"Defending that view, Lineweaver invokes what he calls “the Planet of the Apes fallacy”. In the original movie starring Charlton Heston, humanity gets wiped out and the apes become the dominant species by rapidly evolving human level intelligence. The story is portrayed as if there is “an intelligence niche” that became vacated by the demise of Homo sapiens, with the apes being next in line to fill it.
***
"There is, however, a glimmer of hope for SETI.
"Evolutionary theory remains a work in progress, and in recent years some contrarian biologists have challenged the dogma that there is no directionality in evolution. (my bold)
"They have identified several mechanisms whereby characteristics acquired during the lifetime of an organism seem to be passed on to their offspring, a process known as epigenetic inheritance. This is in stark contrast to standard Darwinism, according to which mutations in offspring arise from purely random errors unconnected to the circumstances of the parent.
"If epigenetic inheritance plays a significant role in the evolution of brains, it is possible to imagine a sort of accelerating IQ phenomenon.
"In fact, the fossil record points to an upward trend in the encephalisation quotient – a measure of brain size relative to body mass – among hominins over the past few million years. Assuming something similar works itself out on other planets too, maybe we are not alone after all."
Comment: Note my bold. I believe there is directionality to evolution from simple to complex. Certainly it cannot be denied consciousness is an amazingly complex current result. But I see Davies as offering little hope for alien life.
Human evolution; needs habitable planets
by David Turell , Tuesday, June 11, 2019, 01:18 (1990 days ago) @ David Turell
This study says few are likely to exist besides us:
https://phys.org/news/2019-06-narrows-advanced-life-universe.html
"In a new study, a UC Riverside–led team discovered that a buildup of toxic gases in the atmospheres of most planets makes them unfit for complex life as we know it.
***
"The team's work, published today in The Astrophysical Journal, shows that accounting for predicted levels of certain toxic gases narrows the safe zone for complex life by at least half—and in some instances eliminates it altogether.
"'This is the first time the physiological limits of life on Earth have been considered to predict the distribution of complex life elsewhere in the universe," said Timothy Lyons, one of the study's co-authors, a distinguished professor of biogeochemistry in UCR's Department of Earth and Planetary Sciences,
"'Imagine a 'habitable zone for complex life' defined as a safe zone where it would be plausible to support rich ecosystems like we find on Earth today," Lyons explained. "Our results indicate that complex ecosystems like ours cannot exist in most regions of the habitable zone as traditionally defined."
***
"'To sustain liquid water at the outer edge of the conventional habitable zone, a planet would need tens of thousands of times more carbon dioxide than Earth has today," said Edward Schwieterman, the study's lead author and a NASA Postdoctoral Program fellow working with Lyons. "That's far beyond the levels known to be toxic to human and animal life on Earth."
"The new study concludes that carbon dioxide toxicity alone restricts simple animal life to no more than half of the traditional habitable zone. For humans and other higher order animals, which are more sensitive, the safe zone shrinks to less than one third of that area.
"What is more, no safe zone at all exists for certain stars, including two of the sun's nearest neighbors, Proxima Centauri and TRAPPIST-1. The type and intensity of ultraviolet radiation that these cooler, dimmer stars emit can lead to high concentrations of carbon monoxide, another deadly gas. Carbon monoxide binds to hemoglobin in animal blood—the compound that transports oxygen through the body. Even small amounts of it can cause the death of body cells due to lack of oxygen.
"Carbon monoxide cannot accumulate on Earth because our hotter, brighter sun drives chemical reactions in the atmosphere that destroy it quickly. Although the team concluded recently that microbial biospheres may be able to thrive on a planet with abundant carbon monoxide, Schwieterman emphasized that "these would certainly not be good places for human or animal life as we know it on Earth."
***
"'I think showing how rare and special our planet is only enhances the case for protecting it," Schwieterman said. "As far as we know, Earth is the only planet in the universe that can sustain human life.'"
Comment: I'm not surprised. Our planet has many fine-tuned and undoubtedly unique features. I suspect we are alone
Human evolution; unique in the universe?
QUOTE: "Evolutionary theory remains a work in progress, and in recent years some contrarian biologists have challenged the dogma that there is no directionality in evolution. (David’s bold)
DAVID: Note my bold. I believe there is directionality to evolution from simple to complex. Certainly it cannot be denied consciousness is an amazingly complex current result. But I see Davies as offering little hope for alien life.
I would also challenge the view that there is no directionality in evolution. It would be absurd to deny that human consciousness is amazingly complex. The great question, however, is how ALL the advances (not just human) from simple bacteria to the complexities of whales and elephants and camels and monarch butterflies and ant colonies etc. have come about. If there is alien life, perhaps it consists of bacteria only. What enabled single cells to create these vast and increasingly complex communities? For a change, David, I am on your side – but of course our whole discussion centres on the various possible explanations: a designer God doing it all, or designing an intelligent mechanism to work autonomously, or the same mechanism evolving from some form of rudimentary panpsychic intelligence, or chance coming up with the right combination in the course of an eternity and infinity of combinations? It seems to me that belief in any of these hypotheses requires a great deal of faith!
Human evolution; unique in the universe?
by David Turell , Tuesday, June 11, 2019, 14:38 (1990 days ago) @ dhw
QUOTE: "Evolutionary theory remains a work in progress, and in recent years some contrarian biologists have challenged the dogma that there is no directionality in evolution. (David’s bold)
DAVID: Note my bold. I believe there is directionality to evolution from simple to complex. Certainly it cannot be denied consciousness is an amazingly complex current result. But I see Davies as offering little hope for alien life.
dhw: I would also challenge the view that there is no directionality in evolution. It would be absurd to deny that human consciousness is amazingly complex. The great question, however, is how ALL the advances (not just human) from simple bacteria to the complexities of whales and elephants and camels and monarch butterflies and ant colonies etc. have come about. If there is alien life, perhaps it consists of bacteria only. What enabled single cells to create these vast and increasingly complex communities? For a change, David, I am on your side – but of course our whole discussion centres on the various possible explanations: a designer God doing it all, or designing an intelligent mechanism to work autonomously, or the same mechanism evolving from some form of rudimentary panpsychic intelligence, or chance coming up with the right combination in the course of an eternity and infinity of combinations? It seems to me that belief in any of these hypotheses requires a great deal of faith!
Yes, you are right in your analysis/ some of use use faith.
Human evolution; we are fattest primate
by David Turell , Thursday, June 27, 2019, 22:21 (1974 days ago) @ David Turell
Another reason we are not chimps:
https://www.sciencedaily.com/releases/2019/06/190626160337.htm
" Despite having nearly identical DNA sequences, chimps and early humans underwent critical shifts in how DNA is packaged inside their fat cells, Swain-Lenz and her Duke colleagues have found. As a result, the researchers say, this decreased the human body's ability to turn "bad" calorie-storing fat into the "good" calorie-burning kind.
***
"Compared to our closest animal relatives, even people with six-pack abs and rippling arms have considerable fat reserves, researchers say. While other primates have less than 9% body fat, a healthy range for humans is anywhere from 14% to 31%.
***
"Normally most of the DNA within a cell is condensed into coils and loops and tightly wound around proteins, such that only certain DNA regions are loosely packed enough to be accessible to the cellular machinery that turns genes on and off.
"The researchers identified roughly 780 DNA regions that were accessible in chimps and macaques, but had become more bunched up in humans. Examining these regions in detail, the team also noticed a recurring snippet of DNA that helps convert fat from one cell type to another.
"Not all fat is created equal, Swain-Lenz explained. Most fat is made up of calorie-storing white fat. It's what makes up the marbling in a steak and builds up around our waistlines. Specialized fat cells called beige and brown fat, on the other hand, can burn calories rather than store them to generate heat and keep us warm.
"One of the reasons we're so fat, the research suggests, is because the regions of the genome that help turn white fat to brown were essentially locked up -- tucked away and closed for business -- in humans but not in chimps.
***
"Humans, like chimps, need fat to cushion vital organs, insulate us from the cold, and buffer us from starvation. But early humans may have needed to plump up for another reason, the researchers say -- as an additional source of energy to fuel our growing, hungry brains.
"In the six to eight million years since humans and chimps went their separate ways, human brains have roughly tripled in size. Chimpanzee brains haven't budged.
"The human brain uses more energy, pound for pound, than any other tissue. Steering fat cells toward calorie-storing white fat rather than calorie-burning brown fat, the thinking goes, would have given our ancestors a survival advantage."
Comment: Our DNA may look like a chimp's but we are very different i kind, as this study shows.
Human evolution; earliest sapiens skull in Europe
by David Turell , Wednesday, July 10, 2019, 21:56 (1961 days ago) @ David Turell
Found in Grecian cave and estimated 210,000 years old:
https://phys.org/news/2019-07-oldest-africa-reset-human-migration.html
"A 210,000-year-old skull has been identified as the earliest modern human remains found outside Africa, putting the clock back on mankind's arrival in Europe by more than 150,000 years, researchers said Wednesday.
"In a startling discovery that changes our understanding of how modern man populated Eurasia, the findings support the idea that Homo sapiens made several, sometimes unsuccessful migrations from Africa over tens of thousands of years.
"Southeast Europe has long been considered a major transport corridor for modern humans from Africa. But until now the earliest evidence of Homo sapiens on the continent dated back only around 50,000 years.
***
"One of them, named Apidima 2 after the cave in which the pair were found, proved to be 170,000 years old and did indeed belong to a Neanderthal.
But, to the shock of scientists, the skull named Apidima 1 pre-dated Apidima 2 by as much as 40,000 years, and was determined to be that of a Homo sapiens.
"That makes the skull by far the oldest modern human remains ever discovered on the continent, and older than any known Homo sapiens specimen outside of Africa.
"'It shows that the early dispersal of Homo sapiens out of Africa not only occurred earlier, before 200,000 years ago, but also reached further geographically, all the way to Europe," Katerina Harvati, a palaeoanthropologist at the Eberhard Karls University of Tuebingen, Germany, told AFP.
***
"But the skull discovery in Greece suggests that Homo sapiens undertook the migration from Africa to southern Europe on "more than one occasion", according to Eric Delson, a professor of anthropology at City University of New York.
"'Rather than a single exit of hominins from Africa to populate Eurasia, there must have been several dispersals, some of which did not result in permanent occupations," said Delson, who was not involved in the Nature study."
Comment: Sapiens may have started in Africa, but the urge to see what is over the next hill came early and must related to the new functions of the enlarged brain.
Human evolution; we hear pitch better than monkeys
by David Turell , Saturday, July 13, 2019, 19:50 (1958 days ago) @ David Turell
New research on the difference between humans and other primates:
https://www.sciencedaily.com/releases/2019/07/190711111913.htm
"In the eternal search for understanding what makes us human, scientists found that our brains are more sensitive to pitch, the harmonic sounds we hear when listening to music, than our evolutionary relative the macaque monkey.
***
"'We found that a certain region of our brains has a stronger preference for sounds with pitch than macaque monkey brains," said Bevil Conway, Ph.D., investigator in the NIH's Intramural Research Program and a senior author of the study published in Nature Neuroscience. "The results raise the possibility that these sounds, which are embedded in speech and music, may have shaped the basic organization of the human brain." (my bold)
***
"At first glance, the scans looked similar and confirmed previous studies. Maps of the auditory cortex of human and monkey brains had similar hot spots of activity regardless of whether the sounds contained tones.
"However, when the researchers looked more closely at the data, they found evidence suggesting the human brain was highly sensitive to tones. The human auditory cortex was much more responsive than the monkey cortex when they looked at the relative activity between tones and equivalent noisy sounds.
"We found that human and monkey brains had very similar responses to sounds in any given frequency range. It's when we added tonal structure to the sounds that some of these same regions of the human brain became more responsive," said Dr. Conway. "These results suggest the macaque monkey may experience music and other sounds differently. In contrast, the macaque's experience of the visual world is probably very similar to our own. It makes one wonder what kind of sounds our evolutionary ancestors experienced."
"Further experiments supported these results. Slightly raising the volume of the tonal sounds had little effect on the tone sensitivity observed in the brains of two monkeys.
"Finally, the researchers saw similar results when they used sounds that contained more natural harmonies for monkeys by playing recordings of macaque calls. Brain scans showed that the human auditory cortex was much more responsive than the monkey cortex when they compared relative activity between the calls and toneless, noisy versions of the calls.
"'This finding suggests that speech and music may have fundamentally changed the way our brain processes pitch," said Dr. Conway. "It may also help explain why it has been so hard for scientists to train monkeys to perform auditory tasks that humans find relatively effortless.'"
Comment: As usual we are very different than monkeys. The bold above raises the question of which came first complex brain or complex sound? Developed human language has involved pitches which need to be appreciated for proper understanding of speech. I think the more complex brain allowed for more complex speech.
Human evolution; we hear pitch better than monkeys
DAVID: New research on the difference between humans and other primates:
https://www.sciencedaily.com/releases/2019/07/190711111913.htm
QUOTE: "In the eternal search for understanding what makes us human, scientists found that our brains are more sensitive to pitch, the harmonic sounds we hear when listening to music, than our evolutionary relative the macaque monkey.”
I really don’t know why the search has to be eternal! I think most of us recognize that we are very different from other primates, just as whales are different from elephants, and shark are different from goldfish. Many would say that the major difference in us is mental rather than physical, but on the other hand many of those people would also say that the mental difference is caused by a physical difference - namely the brain.
"'We found that a certain region of our brains has a stronger preference for sounds with pitch than macaque monkey brains," said Bevil Conway, Ph.D., investigator in the NIH's Intramural Research Program and a senior author of the study published in Nature Neuroscience. "The results raise the possibility that these sounds, which are embedded in speech and music, may have shaped the basic organization of the human brain." (DAVID’s bold)
DAVID: As usual we are very different than monkeys. The bold above raises the question of which came first complex brain or complex sound? Developed human language has involved pitches which need to be appreciated for proper understanding of speech. I think the more complex brain allowed for more complex speech.
I’m not sure why “pitch” is regarded as so significant in relation to human language (as opposed to music), though the link is very clear in bird language:
Bird Senses and How They Use Them - The Spruce
https://www.thespruce.com/birds-five-senses-386441
“Birds hear a smaller frequency range than humans, but they have much more acute sound recognition skills. Birds are especially sensitive to pitch, tone and rhythm changes and use those variations to recognize other individual birds, even in a noisy flock.”
The papers here have been full of stories about Snowball the cockatoo who can dance in rhythm to human music, and about a manta ray which “asked” a diver she knew to remove fishing hooks stuck under her eye and then “thanked” him. An editorial in The Times on Friday also referred to puzzle-solving by dolphins, chimps and corvids (often reported by David on this website) as evidence that “dumb animals are a whole lot cleverer than we thought” which “should encourage us to redouble our efforts to co-exist harmoniously together”. In addition to cleverness I would cite sentience as a factor that should encourage us. For those of us who believe in common descent, it should be crystal clear that no matter how different species are, much of what makes us “human” has actually been inherited from our non-human ancestors.
To David: As for which came first, the idea that the complexities of the brain preceded the complexities of speech fits in with your belief that your God made anatomical changes in advance of the need for them (e.g. changing legs to flippers before sending pre-whales into the water). This also suggests that the changes in the brain give rise to the improvements (= materialism). As you know, I propose the reverse process, whereby the effort to produce more complex speech gave rise to changes in the brain (like the effort to adapt to water giving rise to flippers instead of legs) as the cell communities adapted to new requirements. But I think we’ve probably gone as far as we can along this route.
Human evolution; we hear pitch better than monkeys
by David Turell , Sunday, July 14, 2019, 15:34 (1957 days ago) @ dhw
DAVID: New research on the difference between humans and other primates:
https://www.sciencedaily.com/releases/2019/07/190711111913.htmQUOTE: "In the eternal search for understanding what makes us human, scientists found that our brains are more sensitive to pitch, the harmonic sounds we hear when listening to music, than our evolutionary relative the macaque monkey.”
dhw: I really don’t know why the search has to be eternal! I think most of us recognize that we are very different from other primates, just as whales are different from elephants, and shark are different from goldfish. Many would say that the major difference in us is mental rather than physical, but on the other hand many of those people would also say that the mental difference is caused by a physical difference - namely the brain.
There are major physical changes that humans have not related to the brain when compared to other primates: hand dexterity, different shoulder uses, different pelvis allowing upright posture, vocal apparatus marked changes, etc. There is a large list of anatomic differences, not related to the brain development.
"'We found that a certain region of our brains has a stronger preference for sounds with pitch than macaque monkey brains," said Bevil Conway, Ph.D., investigator in the NIH's Intramural Research Program and a senior author of the study published in Nature Neuroscience. "The results raise the possibility that these sounds, which are embedded in speech and music, may have shaped the basic organization of the human brain." (DAVID’s bold)DAVID: As usual we are very different than monkeys. The bold above raises the question of which came first complex brain or complex sound? Developed human language has involved pitches which need to be appreciated for proper understanding of speech. I think the more complex brain allowed for more complex speech.
dhw: I’m not sure why “pitch” is regarded as so significant in relation to human language (as opposed to music), though the link is very clear in bird language:
Bird Senses and How They Use Them - The Spruce
https://www.thespruce.com/birds-five-senses-386441“Birds hear a smaller frequency range than humans, but they have much more acute sound recognition skills. Birds are especially sensitive to pitch, tone and rhythm changes and use those variations to recognize other individual birds, even in a noisy flock.”
dhw: The papers here have been full of stories about Snowball the cockatoo who can dance in rhythm to human music, and about a manta ray which “asked” a diver she knew to remove fishing hooks stuck under her eye and then “thanked” him. An editorial in The Times on Friday also referred to puzzle-solving by dolphins, chimps and corvids (often reported by David on this website) as evidence that “dumb animals are a whole lot cleverer than we thought” which “should encourage us to redouble our efforts to co-exist harmoniously together”. In addition to cleverness I would cite sentience as a factor that should encourage us. For those of us who believe in common descent, it should be crystal clear that no matter how different species are, much of what makes us “human” has actually been inherited from our non-human ancestors.
You always try to diminish the differences humans have from all other creatures to support your views about how evolution works without god.
dhw: To David: As for which came first, the idea that the complexities of the brain preceded the complexities of speech fits in with your belief that your God made anatomical changes in advance of the need for them (e.g. changing legs to flippers before sending pre-whales into the water). This also suggests that the changes in the brain give rise to the improvements (= materialism). As you know, I propose the reverse process, whereby the effort to produce more complex speech gave rise to changes in the brain (like the effort to adapt to water giving rise to flippers instead of legs) as the cell communities adapted to new requirements. But I think we’ve probably gone as far as we can along this route.
Our differences are obvious. Yes, far enough.
Human evolution; we hear pitch better than monkeys
dhw: I really don’t know why the search has to be eternal! I think most of us recognize that we are very different from other primates, just as whales are different from elephants, and shark are different from goldfish. Many would say that the major difference in us is mental rather than physical, but on the other hand many of those people would also say that the mental difference is caused by a physical difference - namely the brain.
DAVID: There are major physical changes that humans have not related to the brain when compared to other primates: hand dexterity, different shoulder uses, different pelvis allowing upright posture, vocal apparatus marked changes, etc. There is a large list of anatomic differences, not related to the brain development.
Agreed. My point was twofold: what sets us apart from ALL other species is our mental capacity (see below), but at the same time I wanted to draw attention to the fact that some people believe this is actually caused by a physical difference (the complexities of the brain).
dhw: […] For those of us who believe in common descent, it should be crystal clear that no matter how different species are, much of what makes us “human” has actually been inherited from our non-human ancestors.
DAVID: You always try to diminish the differences humans have from all other creatures to support your views about how evolution works without god.
I have never ever denied the enormous gulf between our mental capacities and those of our fellow animals. But that does not invalidate my statement, the purpose of which was to support The Times in its plea that we should respect our fellow animals, with whom we have so much in common. Nothing whatsoever to do with “evolution works without God”, and you know perfectly well that the hypothesis relating to cellular intelligence allows for God as the inventor.
Human evolution; we hear pitch better than monkeys
by David Turell , Monday, July 15, 2019, 15:39 (1956 days ago) @ dhw
dhw: I really don’t know why the search has to be eternal! I think most of us recognize that we are very different from other primates, just as whales are different from elephants, and shark are different from goldfish. Many would say that the major difference in us is mental rather than physical, but on the other hand many of those people would also say that the mental difference is caused by a physical difference - namely the brain.
DAVID: There are major physical changes that humans have not related to the brain when compared to other primates: hand dexterity, different shoulder uses, different pelvis allowing upright posture, vocal apparatus marked changes, etc. There is a large list of anatomic differences, not related to the brain development.
Agreed. My point was twofold: what sets us apart from ALL other species is our mental capacity (see below), but at the same time I wanted to draw attention to the fact that some people believe this is actually caused by a physical difference (the complexities of the brain).
dhw: […] For those of us who believe in common descent, it should be crystal clear that no matter how different species are, much of what makes us “human” has actually been inherited from our non-human ancestors.
DAVID: You always try to diminish the differences humans have from all other creatures to support your views about how evolution works without God.
dhw: I have never ever denied the enormous gulf between our mental capacities and those of our fellow animals. But that does not invalidate my statement, the purpose of which was to support The Times in its plea that we should respect our fellow animals, with whom we have so much in common. Nothing whatsoever to do with “evolution works without God”, and you know perfectly well that the hypothesis relating to cellular intelligence allows for God as the inventor.
I agree. As we have dominion over all animals we certainly should carefully relate to them. I do recognize your hypothesis which allows God to sneak in.
Human evolution; a herd of ancestors
by David Turell , Thursday, July 18, 2019, 15:59 (1953 days ago) @ David Turell
There is genetic evidence of at least six human strains in the past:
https://www.sciencedaily.com/releases/2019/07/190715094918.htm
"Genetic analysis has revealed that the ancestors of modern humans interbred with at least five different archaic human groups as they moved out of Africa and across Eurasia.
"While two of the archaic groups are currently known -- the Neandertals and their sister group the Denisovans from Asia -- the others remain unnamed and have only been detected as traces of DNA surviving in different modern populations. Island Southeast Asia appears to have been a particular hotbed of diversity.
***
"'Each of us carry within ourselves the genetic traces of these past mixing events," says first author Dr João Teixeira, Australian Research Council Research Associate, ACAD, at the University of Adelaide. "These archaic groups were widespread and genetically diverse, and they survive in each of us. Their story is an integral part of how we came to be.
"'For example, all present-day populations show about 2% of Neandertal ancestry which means that Neandertal mixing with the ancestors of modern humans occurred soon after they left Africa, probably around 50,000 to 55,000 years ago somewhere in the Middle East."
"But as the ancestors of modern humans travelled further east they met and mixed with at least four other groups of archaic humans.
"'Island Southeast Asia was already a crowded place when what we call modern humans first reached the region just before 50,000 years ago," says Dr Teixeira. "At least three other archaic human groups appear to have occupied the area, and the ancestors of modern humans mixed with them before the archaic humans became extinct."
"Using additional information from reconstructed migration routes and fossil vegetation records, the researchers have proposed there was a mixing event in the vicinity of southern Asia between the modern humans and a group they have named "Extinct Hominin 1."
"Other interbreeding occurred with groups in East Asia, in the Philippines, the Sunda shelf (the continental shelf that used to connect Java, Borneo and Sumatra to mainland East Asia), and possibly near Flores in Indonesia, with another group they have named "Extinct Hominin 2."
"'We knew the story out of Africa wasn't a simple one, but it seems to be far more complex than we have contemplated," says Dr Teixeira. "The Island Southeast Asia region was clearly occupied by several archaic human groups, probably living in relative isolation from each other for hundreds of thousands of years before the ancestors of modern humans arrived.
"The timing also makes it look like the arrival of modern humans was followed quickly by the demise of the archaic human groups in each area."
Comment: This discussion certainly includes the recently discovered 'hobbits'. What this means to me is there was a genetic drive to produce hominins on the way to a goal of modern humans.
Human evolution; very early relative from 3.8 myo
by David Turell , Thursday, August 29, 2019, 00:25 (1912 days ago) @ David Turell
A recognized early ape-like creature with some later attributes of hominin features:
https://cosmosmagazine.com/palaeontology/ape-like-face-of-early-human-ancestor-revealed...
"The ape-like face of one of our earliest known human ancestors has been revealed for the first time, thanks to the discovery of a nearly complete skull in Ethiopia.
"The cranium – the skull minus its lower jaw – belongs to Australopithecus anamensis, and its owner lived in the Afar basin in Ethiopia around 3.8 million years ago.
"Australopiths are thought to be the direct ancestors of the early members of our own genus, Homo, which arose with Homo habilis roughly 2.4 million years ago.
"Several Australopith species have been identified. The best-known of these is Australopithecus afarensis, the species that counts Lucy as its famous flag-bearer.
"A. anamensis is the oldest member of the Australopiths, yet it is far less well known, in part because of its lacklustre fossil record, consisting of a smattering of limb bones, jaw bones and disembodied teeth.
***
"Its teeth and upper jaw clearly mark it as a member of A. anamensis, and an accompanying paper date the sediments around the remains as 3.8 million years old, similar in age to other A. anamensis finds.
***
"The cranium was found in two parts, with the upper jaw cleaved off from the rest of the head. These two pieces fit together perfectly, says Haile-Selassie, and other smaller pieces, including the orbit of one eye, were found near-by.
"Together, the fossils give a clear picture of what the face of A. anamensis looked like, and how it fits into the human family tree.
***
"Many of the features of A. anamensis are ape-like. It had a pronounced snout and its brain would have been similar in size to that of a chimpanzee.
"But other features are reminiscent of hominin species that lived much later.
"For example, its cheek bones were forward-facing, foreshadowing the flatter faces that developed in Homo habilis and later, in our own species.
***
"In the popular imagination, human evolution proceeds through a series of species, each one being a more evolved version of the last.
“'Most of the time, that’s not really the case,” says Spoor.
"Species often represent separate branches on a tree, with the direct ancestors – the branchpoints – leaving no trace. “You hardly ever find the real ancestor of something else,” says Spoor.
"But for a long time, A. anamensis was believed to be one of those rare cases of being a direct ancestor to A. afarensis – Lucy.
"This new find challenges that text-book perfect example. For a start, the two species overlapped for a period of at least 100,000 years.
“'What's great about the paper is that it challenges this theory about linear evolution between the two species,” says Spoor.
"However, Haile-Selassie says the discovery doesn’t rule this out. One population of A. anamensis could have given rise to A. afarensis, while others diverged in a different direction. Without more fossils, it’s hard to know for sure. "
Comment: It looks like we came from a bush of pre-hominins and hominins. To me it looks as if God was willing to take lots of time to finally evolve humans, just as these findings show.
Human evolution; hand signals in us, apes and monkeys
by David Turell , Thursday, September 12, 2019, 15:41 (1897 days ago) @ David Turell
We certainly do a lot of communication with our hands as we speak. Other primates also use hand signal:
http://nautil.us/issue/76/language/the-communication-we-share-with-apes?mc_cid=c9f8dafe...
"Many primate species use gestures to communicate with others in their groups. Wild chimpanzees have been seen to use at least 66 different hand signals and movements to communicate with each other. Lifting a foot toward another chimp means “climb on me,” while stroking their mouth can mean “give me the object.” In the past, researchers have also successfully taught apes more than 100 words in sign language. “The idea is to look at language, not just as speech, but seeing it as a constellation of many cognitive properties,” says Meguerditchian.
"Most language properties involve asymmetric organization of the human brain between the two hemispheres. Given that gestures in primates seem to involve several key properties that underpin spoken language, Meguerditchian wants to see if primates undergo similar brain asymmetry when they gesture to each other. “If you want to understand the origins of language, you need to understand not only animal cognition and communication but also its brain specialization in comparison with humans, and that is what we do in primate species,” he says.
"Given both primates and humans can communicate through gestures, it provides a way of comparing how gestures are related to brain asymmetry for language and to unravel whether there are differences in how each species communicate. Meguerditchian is studying both adult and baby baboons to see which gestures they learn and the parts of their brains that might be involved. “When baboons invite someone to play, they will use their hands,” he says. “Baboons are also able to point to food they want and use gaze, like children can.”
"In human babies, which learn to gesture at objects before they can speak, the left side of their brain seems to be engaged when they do so. Certain regions on the left side of our brain, such as Broca’s area, are especially important when we speak. Meguerditchian is using magnetic resonance imaging to study baboon baby brains to see if they use a similar part of their brain when they learn to gesture. “The questions is, if language is mostly in the left hemisphere in humans, what about gesture in non-human primates? If it is the same system, which was used by a common ancestor between us, gesture in baboons might also be related to this left hemisphere specialization of the brain in baboons.”
"So far, early results from 27 brain scans of baby baboons suggest that his hypothesis is correct, and apes use similar asymmetric brain areas when they gesture as humans do when they gesture and speak.
***
“'The visual aspect of language is much more important than linguists used to believe,” says Sandler, who is leading a project called the Grammar of the Body (GRAMBY). Part of the work has involved studying the complexity of newly emerging sign languages and sign language in a number of different cultures. “Different parts of the body convey different linguistic functions,” she says. “The hands convey words, but the intonation, so the rise and fall of voice, is conveyed in sign language by facial expressions and different tilts of the head.”
"She and her colleagues also studied video footage of chimp displays at a Zambian wildlife orphanage to see if they use combinations of facial and gestural signals to convey complex meanings. Humans can knit together smaller elements of meaning according to known rules to form composites, which gives us the ability to communicate an infinite number of messages.
Sandler offers the example of “train station,” which we know is a station for trains because of the words and rules we know apply in English. She has also studied the expression of extreme emotion in athletes who have won and lost a competition. Taking her studies together, she concludes that humans are “compositional communicators.'”
Comment: It is not surprising that, as we are descended for earlier primates, we use hand signals as they do with the same parts of the brain involved. Still we speak words and they don't. We differ in spoken language and consciousness and that is a giant leap in evolution, which to my mind proves God exists as the source of that specialness.
Human evolution; limited monkey vocal calls
by David Turell , Tuesday, September 03, 2019, 23:10 (1906 days ago) @ David Turell
This paper analyzes and shows how limited are monkey vocal calls:
https://phys.org/news/2019-09-world-monkeys-combine-items-speechbut.html
"The utterances of Old World monkeys, some of our primate cousins, may be more sophisticated than previously realized—but even so, they display constraints that reinforce the singularity of human language, according to a new study co-authored by an MIT linguist.
"The study reinterprets evidence about primate language and concludes that Old World monkeys can combine two items in a language sequence. And yet, their ability to combine items together seems to stop at two. The monkeys are not able to recombine language items in the same open-ended manner as humans, whose languages generate an infinite variety of sequences.
"We are saying the two systems are fundamentally different," says Shigeru Miyagawa, an MIT linguist and co-author of a new paper detailing the study's findings.
"That might seem apparent. But the study's precise claim—that even if other primates can combine terms, they cannot do so in the way humans do—emphasizes the profound gulf in cognitive ability between humans and some of our closest relatives.
"'If what we're saying in this paper is right, there's a big break between two [items in a sentence], and [the potential for] infinity," Miyagawa adds. "There is no three, there is no four, there is no five. Two and infinity. And that is the break between a nonhuman primate and human primates."
"To conduct the study, Miyagawa and Clarke re-evaluated recordings of Old World monkeys, a family of primates with over 100 species, including baboons, macaques, and the probiscis monkey.
The language of some of these species has been studied fairly extensively. Research starting in the 1960s, for example, established that vervet monkeys have specific calls when they see leopards, eagles, and snakes, all of which requires different kinds of evasive action.
"Similarly, tamarin monkeys have one alarm call to warn of aerial predators and one to warn of ground-based predators.
"In other cases, though, Old World monkeys seem capable of combining calls to create new messages. The putty-nosed monkey of West Africa, for example, has a general alarm call, which scientists call "pyow," and a specific alarm call warning of eagles, which is "hack."
"Sometimes these monkeys combine them in "pyow-hack" sequences of varying length, a third message that is used to spur group movement.
"To conduct the study, Miyagawa and Clarke re-evaluated recordings of Old World monkeys, a family of primates with over 100 species, including baboons, macaques, and the probiscis monkey.
"The language of some of these species has been studied fairly extensively. Research starting in the 1960s, for example, established that vervet monkeys have specific calls when they see leopards, eagles, and snakes, all of which requires different kinds of evasive action. Similarly, tamarin monkeys have one alarm call to warn of aerial predators and one to warn of ground-based predators.
"In other cases, though, Old World monkeys seem capable of combining calls to create new messages. The putty-nosed monkey of West Africa, for example, has a general alarm call, which scientists call "pyow," and a specific alarm call warning of eagles, which is "hack."
Sometimes these monkeys combine them in "pyow-hack" sequences of varying length, a third message that is used to spur group movement.
***
"As a result, Miyagawa adds, "Yes, those calls are made up of two items. Looking at the data very carefully it is apparent. The other thing that is apparent is that they cannot combine more than two things. We decided there is a whole different system here," compared to human language.
***
"'It's not the human system," Miyagawa says. In the paper, Miyagawa and Clarke contend that the monkeys' ability to combine these terms means they are merely deploying a "dual-compartment frame" which lacks the capacity for greater complexity.
Miyagawa also notes that when the Old World monkeys speak, they seem to use a part of the brain known as the frontal operculum. Human language is heavily associated with Broca's area, a part of the brain that seems to support more complex operations.
"If the interpretation of Old World monkey language that Miyagawa and Clarke put forward here holds up, then humans' ability to harness Broca's area for language may specifically have enabled them to recombine language elements as other primates cannot—by enabling us to link more than two items together in speech.
***
"'There's been all this effort to teach monkeys human language that didn't succeed," Miyagawa notes. "But that doesn't mean we can't learn from them.'"
Comment: We are different in kind to the point that we use a different area of the brain for speech. How did brain cell committees (from dhw) plan that move?
Human evolution; early ancestor probable upright posture
by David Turell , Friday, September 20, 2019, 20:23 (1889 days ago) @ David Turell
A new fossil find:
https://scitechdaily.com/new-view-of-human-evolution-unearthed-by-rare-10-million-year-...
"Near an old mining town in Central Europe, known for its picturesque turquoise-blue quarry water, lay Rudapithecus. For 10 million years, the fossilized ape waited in Rudabánya, Hungary, to add its story to the origins of how humans evolved.
"What Rudabánya yielded was a pelvis — among the most informative bones of a skeleton, but one that is rarely preserved. An international research team led by Carol Ward at the University of Missouri analyzed this new pelvis and discovered that human bipedalism — or the ability for people to move on two legs — might possibly have deeper ancestral origins than previously thought.
***
“'Rudapithecus was pretty ape-like and probably moved among branches like apes do now — holding its body upright and climbing with its arms,” said Ward, a Curators Distinguished Professor of Pathology and Anatomical Sciences in the MU School of Medicine and lead author on the study. “However, it would have differed from modern great apes by having a more flexible lower back, which would mean when Rudapithecus came down to the ground, it might have had the ability to stand upright more as humans do. This evidence supports the idea that rather than asking why human ancestors stood up from all fours, perhaps we should be asking why our ancestors never dropped down on all fours in the first place.” (my bolds)
"Modern African apes have a long pelvis and short lower back because they are such large animals, which is one reason why they typically walk on all fours when on the ground. Humans have longer, more flexible lower backs, which allow them to stand upright and walk efficiently on two legs, a hallmark characteristic of human evolution. Ward said if humans evolved from an African ape-like body build, substantial changes to lengthen the lower back and shorten the pelvis would have been required. If humans evolved from an ancestor more like Rudapithecus, this transition would have been much more straightforward.
“We were able to determine that Rudapithecus would have had a more flexible torso than today’s African apes because it was much smaller — only about the size of a medium dog,” Ward said. “This is significant because our finding supports the idea suggested by other evidence that human ancestors might not have been built quite like modern African apes.”
Ward teamed up with Begun to study the pelvis along with MU alumna Ashley Hammond, Assistant Curator of Biological Anthropology at the American Museum of Natural History, and J. Michael Plavcan, a professor of anthropology at the University of Arkansas. Since the fossil was not 100% complete, the team used new 3D modeling techniques to digitally complete its shape, then compared their models with modern animals. Ward said their next step will be to conduct a 3D analysis of other fossilized body parts of Rudapithecus to gather a more complete picture of how it moved, giving more insight into the ancestors of African apes and humans.
From the abstract of the article:
https://www.sciencedirect.com/science/article/pii/S0047248419300685?via%3Dihub
A recently discovered partial hipbone attributed to the 10 million-year-old fossil ape Rudapithecus hungaricus from Rudabánya, Hungary, differs from the hipbones of cercopithecids and earlier apes in functionally significant ways....However, this fossil lacks the long lower ilium that characterizes chimpanzees, gorillas and orangutans, associated with their reduction of the number of lumbar vertebrae. The R. hungaricus pelvis demonstrates that the extreme elongation of the lower ilium seen in extant great apes does not necessarily accompany adaptation to orthograde posture and forelimb-dominated arboreal locomotion in hominoid evolution. Lower iliac elongation appears to have occurred independently in each lineage of extant great apes, supporting the hypothesis that the last common ancestor of Pan and Homo may have been unlike extant great apes in pelvic length and lower back morphology.
Comment: The path to bipedalism obviously started well before the brain enlarged but allowed the hands to become more developed ahead of time, anticipating the further development of the brain's enlargement and capacity for mental development. It didn't require movement to the Savannah to develop as previously proposed, noting my bolds above. I view this as God engineering evolution in a logical fashion ten million years ago.
Human evolution; early ancestor probable upright posture
QUOTES: "Near an old mining town in Central Europe, known for its picturesque turquoise-blue quarry water, lay Rudapithecus. For 10 million years, the fossilized ape waited in Rudabánya, Hungary, to add its story to the origins of how humans evolved."
“'Rudapithecus was pretty ape-like and probably moved among branches like apes do now — holding its body upright and climbing with its arms,” said Ward, a Curators Distinguished Professor of Pathology and Anatomical Sciences in the MU School of Medicine and lead author on the study. “However, it would have differed from modern great apes by having a more flexible lower back, which would mean when Rudapithecus came down to the ground, it might have had the ability to stand upright more as humans do. This evidence supports the idea that rather than asking why human ancestors stood up from all fours, perhaps we should be asking why our ancestors never dropped down on all fours in the first place [/b].” (David’s bolds)
Interesting that this is a European fossil. Since there are different types of hominin and homo, one might conclude that different apes evolved differently in different parts of the world. One would expect transitional species to have moved among branches as well as on the ground, and (re your second bold) why should we presume that Rudapithecus did not descend from an all-fours ape? Somewhere along the line, some apes descended from the trees and took to bipedalism. We do not have, and are unlikely to find, a complete set of fossils for every single stage of descent!
DAVID: The path to bipedalism obviously started well before the brain enlarged but allowed the hands to become more developed ahead of time, anticipating the further development of the brain's enlargement and capacity for mental development. It didn't require movement to the Savannah to develop as previously proposed, noting my bolds above. I view this as God engineering evolution in a logical fashion ten million years ago.
Maybe there was more than one path to bipedalism, but I would agree with the whole of your first sentence except for the cryptic "ahead of time", for which I would substitute "when needed": it is logical that the move to a new environment engendered bipedalism, giving rise to new requirements, and so the rest followed on logically. What I would find illogical is (a) your theory that your God engineered changes before our ancestors moved into their new environment, and (b) your theory that he specially designed every change, itsy-bitsy, over millions of years, in different species of hominins and homos, when his sole purpose from the very beginning was to design H. sapiens. For me, all these separate developments in separate species and separate places suggest the natural divergences created by mechanisms (perhaps God-given) that operate independently of one single designer with just one goal in mind.
Human evolution; early ancestor probable upright posture
by David Turell , Saturday, September 21, 2019, 19:04 (1888 days ago) @ dhw
QUOTES: "Near an old mining town in Central Europe, known for its picturesque turquoise-blue quarry water, lay Rudapithecus. For 10 million years, the fossilized ape waited in Rudabánya, Hungary, to add its story to the origins of how humans evolved."
“'Rudapithecus was pretty ape-like and probably moved among branches like apes do now — holding its body upright and climbing with its arms,” said Ward, a Curators Distinguished Professor of Pathology and Anatomical Sciences in the MU School of Medicine and lead author on the study. “However, it would have differed from modern great apes by having a more flexible lower back, which would mean when Rudapithecus came down to the ground, it might have had the ability to stand upright more as humans do. This evidence supports the idea that rather than asking why human ancestors stood up from all fours, perhaps we should be asking why our ancestors never dropped down on all fours in the first place [/b].” (David’s bolds)
dhw; Interesting that this is a European fossil. Since there are different types of hominin and homo, one might conclude that different apes evolved differently in different parts of the world. One would expect transitional species to have moved among branches as well as on the ground, and (re your second bold) why should we presume that Rudapithecus did not descend from an all-fours ape? Somewhere along the line, some apes descended from the trees and took to bipedalism. We do not have, and are unlikely to find, a complete set of fossils for every single stage of descent!
You are correct. Fossils are few. However on page 258 of my book, Atheist Delusion is Dr. Fuller's exposition of a transitional vertebrae of a hominid form from 21 million years ago in a monkey fossil. Again well before descending the trees. So i repeat my comment:
DAVID: The path to bipedalism obviously started well before the brain enlarged but allowed the hands to become more developed ahead of time, anticipating the further development of the brain's enlargement and capacity for mental development. It didn't require movement to the Savannah to develop as previously proposed, noting my bolds above. I view this as God engineering evolution in a logical fashion ten million years ago.dhw: Maybe there was more than one path to bipedalism, but I would agree with the whole of your first sentence except for the cryptic "ahead of time", for which I would substitute "when needed": it is logical that the move to a new environment engendered bipedalism, giving rise to new requirements, and so the rest followed on logically. What I would find illogical is (a) your theory that your God engineered changes before our ancestors moved into their new environment, and (b) your theory that he specially designed every change, itsy-bitsy, over millions of years, in different species of hominins and homos, when his sole purpose from the very beginning was to design H. sapiens. For me, all these separate developments in separate species and separate places suggest the natural divergences created by mechanisms (perhaps God-given) that operate independently of one single designer with just one goal in mind.
Again, the early evidence in time, although scattered, supports my approach not yours; I see preparatory changes, as the authors do, well ahead of the time to descend from the trees. You are still Darwinian in trying to find needs to drive evolution, while as Gould showed, all species arrive fully changed.
Human evolution; early ancestor probable upright posture
dhw:: Interesting that this is a European fossil. Since there are different types of hominin and homo, one might conclude that different apes evolved differently in different parts of the world. One would expect transitional species to have moved among branches as well as on the ground, and (re your second bold) why should we presume that Rudapithecus did not descend from an all-fours ape? Somewhere along the line, some apes descended from the trees and took to bipedalism. We do not have, and are unlikely to find, a complete set of fossils for every single stage of descent!
DAVID: You are correct. Fossils are few. However on page 258 of my book, Atheist Delusion is Dr. Fuller's exposition of a transitional vertebrae of a hominid form from 21 million years ago in a monkey fossil. Again well before descending the trees.
How do you know it was “well before descending the trees”? Even monkeys descend from the trees! We have absolutely no way of knowing how long all these different apes and hominids spent up the trees and down on the ground!
DAVID: So i repeat my comment:
DAVID: The path to bipedalism obviously started well before the brain enlarged but allowed the hands to become more developed ahead of time, anticipating the further development of the brain's enlargement and capacity for mental development. It didn't require movement to the Savannah to develop as previously proposed, noting my bolds above. I view this as God engineering evolution in a logical fashion ten million years ago.
dhw: Maybe there was more than one path to bipedalism, but I would agree with the whole of your first sentence except for the cryptic "ahead of time", for which I would substitute "when needed": it is logical that the move to a new environment engendered bipedalism, giving rise to new requirements, and so the rest followed on logically
DAVID: Again, the early evidence in time, although scattered, supports my approach not yours; I see preparatory changes, as the authors do, well ahead of the time to descend from the trees. You are still Darwinian in trying to find needs to drive evolution, while as Gould showed, all species arrive fully changed.
Yes indeed, I find it perfectly logical that organisms would change in response to need or to opportunity. Our classic example has always been the whale, and I find your theory that your God changed legs to flippers before the pre-whale entered the water almost laughable beside the theory that legs changed to flippers as a RESULT of the pre-whale entering the water (for whatever reason). The same applies to our various ancestors. I envisage them spending increasing amounts of time on the ground (for whatever reason), and their bodies adapting to cope with the different conditions. What do you mean by “fully changed”? All species (in the narrow sense of variations) are fully changed in the sense that they are individual, functioning life forms. You have referred us to p. 258 of your excellent The Atheist Delusion and to Dr Filler’s findings. I quote:
p. 258: “He demonstrates changes in lateral processes that begin to allow for the development of completely upright posture over the the course of the next 20 million years of evolution.”
It took 20 million years for the “complete change” we are discussing! And it took umpteen different “species” of hominid and homo to get there! And so apparently your always-in-control God, whose one purpose was to specially design H. sapiens, either preprogrammed all these different changes 3.8 billion years ago, or kept fiddling and twiddling with hominid/homo anatomies for 20 million years in anticipation of each change in their environment! No wonder you have no idea why he would have chosen this method of “evolving” (= special designing) the only thing he wanted to evolve.
xxxxxx
Under “Evolution and humans: big brain birth canal”:
QUOTE: Preliminary work on the pelvis of the recently discovered 1.98 million-year-old hominin Australopithecus sediba found it to possess a unique combination of Homo and Australopithecus-like features.
All complete in themselves, but suggestive of convergent evolution as each “species” works out its own evolutionary course.
Human evolution; early ancestor probable upright posture
by David Turell , Sunday, September 22, 2019, 16:02 (1887 days ago) @ dhw
DAVID: You are correct. Fossils are few. However on page 258 of my book, Atheist Delusion is Dr. Fuller's exposition of a transitional vertebrae of a hominid form from 21 million years ago in a monkey fossil. Again well before descending the trees.
How do you know it was “well before descending the trees”? Even monkeys descend from the trees! We have absolutely no way of knowing how long all these different apes and hominids spent up the trees and down on the ground!
Exactly. Chimps are constantly up and down for six million years and they are still chimps. There has to be driving force to create humans and the fossil changes point to preparatory, unnecessary at the time, early changes by the driving force, God.
DAVID: Again, the early evidence in time, although scattered, supports my approach not yours; I see preparatory changes, as the authors do, well ahead of the time to descend from the trees. You are still Darwinian in trying to find needs to drive evolution, while as Gould showed, all species arrive fully changed.dhw: Yes indeed, I find it perfectly logical that organisms would change in response to need or to opportunity. Our classic example has always been the whale, and I find your theory that your God changed legs to flippers before the pre-whale entered the water almost laughable beside the theory that legs changed to flippers as a RESULT of the pre-whale entering the water (for whatever reason). The same applies to our various ancestors. I envisage them spending increasing amounts of time on the ground (for whatever reason), and their bodies adapting to cope with the different conditions.
Again that is no explanation when we see chimps unchanged!
dhw: What do you mean by “fully changed”? All species (in the narrow sense of variations) are fully changed in the sense that they are individual, functioning life forms. You have referred us to p. 258 of your excellent The Atheist Delusion and to Dr Filler’s findings. I quote:
p. 258: “He demonstrates changes in lateral processes that begin to allow for the development of completely upright posture over the the course of the next 20 million years of evolution.”
dhw: It took 20 million years for the “complete change” we are discussing! And it took umpteen different “species” of hominid and homo to get there! And so apparently your always-in-control God, whose one purpose was to specially design H. sapiens, either preprogrammed all these different changes 3.8 billion years ago, or kept fiddling and twiddling with hominid/homo anatomies for 20 million years in anticipation of each change in their environment! No wonder you have no idea why he would have chosen this method of “evolving” (= special designing) the only thing he wanted to evolve.
As usual 'I have no idea' why God chose to evolve, but there is much evidence of pre-planning, with slight unnecessary changes in advance of full changed new species . New species are fully changed, as Gould always claimed.
xxxxxxUnder “Evolution and humans: big brain birth canal”:
QUOTE: Preliminary work on the pelvis of the recently discovered 1.98 million-year-old hominin Australopithecus sediba found it to possess a unique combination of Homo and Australopithecus-like features.
dhw: All complete in themselves, but suggestive of convergent evolution as each “species” works out its own evolutionary course.
The 'homo' features are pre-planned preparations for a full new species. And of course re' my comment, you have no answer for birth canal changes to accommodate a bigger baby head, when it involves three individuals with their individual DNA's: father, mother and baby itself.
Human evolution; early ancestor probable upright posture
DAVID: […] on page 258 of my book, Atheist Delusion is Dr. Fuller's exposition of a transitional vertebrae of a hominid form from 21 million years ago in a monkey fossil. Again well before descending the trees.
Dhw: How do you know it was “well before descending the trees”? Even monkeys descend from the trees! We have absolutely no way of knowing how long all these different apes and hominids spent up the trees and down on the ground!
DAVID: Exactly. Chimps are constantly up and down for six million years and they are still chimps. There has to be driving force to create humans and the fossil changes point to preparatory, unnecessary at the time, early changes by the driving force, God.
You seem to think that all animals live under the same conditions at all times and in all places or, if there are changes, they all respond in the same way. All we know is that some of our earliest ancestors began to develop traits of bipedalism! Instead of your God saying: “I want to specially design a totally upright H. sapiens, and so I’ll start by specially designing bits and pieces that aren’t necessary yet”, I suggest we have local conditions in which particular groups of “chimps” (or whatever) find that there’s more to life than living in trees, and there are even better prospects down on the ground. Hence various species of hominids and homos over approx. 21 million years according to Dr Filler.
Dhw: No wonder you have no idea why he would have chosen this method of “evolving” (= special designing) the only thing he wanted to evolve.
DAVID: As usual 'I have no idea' why God chose to evolve, but there is much evidence of pre-planning, with slight unnecessary changes in advance of full changed new species. New species are fully changed, as Gould always claimed.
There is evidence only of change. What do you mean by “fully changed”? All of these species were fully changed in the sense that they were individual, functioning life forms. And what on earth would be the point of your God preprogramming or dabbling unnecessary changes? I suggest that these changes would only have come into being and survived if they had been useful. And yes, that is Darwinian – and it is also sheer common sense.
QUOTE: Preliminary work on the pelvis of the recently discovered 1.98 million-year-old hominin Australopithecus sediba found it to possess a unique combination of Homo and Australopithecus-like features.
dhw: All complete in themselves, but suggestive of convergent evolution as each “species” works out its own evolutionary course.
DAVID: The 'homo' features are pre-planned preparations for a full new species. And of course re' my comment, you have no answer for birth canal changes to accommodate a bigger baby head, when it involves three individuals with their individual DNA's: father, mother and baby itself.
The ‘homo’ features worked perfectly well for that particular “fully changed” “full new” species! You claim to believe in common descent, and so every single species in which there is a father, mother and baby had to coordinate their DNA to accommodate whatever changes led to speciation. You have your God dabbling or preprogramming ALL changes in advance of their being needed! In the theistic version of my hypothesis, I have your God designing the autonomous mechanism which enables the cell communities to cooperate and reconstruct themselves according to new demands as they arise. Change in response to need, not in anticipation of it.
Human evolution; early ancestor probable upright posture
by David Turell , Monday, September 23, 2019, 18:12 (1886 days ago) @ dhw
DAVID: Exactly. Chimps are constantly up and down for six million years and they are still chimps. There has to be driving force to create humans and the fossil changes point to preparatory, unnecessary at the time, early changes by the driving force, God.
dhw: You seem to think that all animals live under the same conditions at all times and in all places or, if there are changes, they all respond in the same way. All we know is that some of our earliest ancestors began to develop traits of bipedalism! Instead of your God saying: “I want to specially design a totally upright H. sapiens, and so I’ll start by specially designing bits and pieces that aren’t necessary yet”, I suggest we have local conditions in which particular groups of “chimps” (or whatever) find that there’s more to life than living in trees, and there are even better prospects down on the ground. Hence various species of hominids and homos over approx. 21 million years according to Dr Filler.
A total non-answer to the point above. Dr. filler's point is mine. Why a tiny inconsequential lumbar change 212 million years ago? It didn't change the lifestyle of that monkey and wasn't necessary at that time.
Dhw: No wonder you have no idea why he would have chosen this method of “evolving” (= special designing) the only thing he wanted to evolve.DAVID: As usual 'I have no idea' why God chose to evolve, but there is much evidence of pre-planning, with slight unnecessary changes in advance of full changed new species. New species are fully changed, as Gould always claimed.
dhw: There is evidence only of change. What do you mean by “fully changed”? All of these species were fully changed in the sense that they were individual, functioning life forms. And what on earth would be the point of your God preprogramming or dabbling unnecessary changes? I suggest that these changes would only have come into being and survived if they had been useful. And yes, that is Darwinian – and it is also sheer common sense.
But the slightly changed vertebrae changed nothing at the time for the monkey's lifestyle and was not required by external new requirements, considering your Darwin comment.
QUOTE: Preliminary work on the pelvis of the recently discovered 1.98 million-year-old hominin Australopithecus sediba found it to possess a unique combination of Homo and Australopithecus-like features.dhw: All complete in themselves, but suggestive of convergent evolution as each “species” works out its own evolutionary course.
DAVID: The 'homo' features are pre-planned preparations for a full new species. And of course re' my comment, you have no answer for birth canal changes to accommodate a bigger baby head, when it involves three individuals with their individual DNA's: father, mother and baby itself.
dhw: The ‘homo’ features worked perfectly well for that particular “fully changed” “full new” species! You claim to believe in common descent, and so every single species in which there is a father, mother and baby had to coordinate their DNA to accommodate whatever changes led to speciation. You have your God dabbling or preprogramming ALL changes in advance of their being needed! In the theistic version of my hypothesis, I have your God designing the autonomous mechanism which enables the cell communities to cooperate and reconstruct themselves according to new demands as they arise.
Cell committees cannot plan and design. Thah is obvious. You can invent all you want about 'my God'. I view it as pure invention, not supported by my view of a purposeful, in-control God.
dhw: Change in response to need, not in anticipation of it.
Totally opposite the Filler thought and mine. The minor change has no apparent current use and simply portends a future anatomic changed structure. This supports my concept of pre-planning by God and is something which refutes your denial of God's pre-planning.
Human evolution; Africa has 90% of the evolution
by David Turell , Monday, September 23, 2019, 20:58 (1886 days ago) @ David Turell
A theoretical essay:
https://phys.org/news/2019-09-modern-humans-species.html
"...a group of researchers argues that our evolutionary past must be understood as the outcome of dynamic changes in connectivity, or gene flow, between early humans scattered across Africa. Viewing past human populations as a succession of discrete branches on an evolutionary tree may be misleading, they said, because it reduces the human story to a series of "splitting times" which may be illusory.
"According to archaeologist Dr. Eleanor Scerri and geneticists Dr. Lounès Chikhi and Professor Mark Thomas, the quest for a single original location for modern humans is a wild goose chase. "People like us began to appear sometime between 500,000 and 300,000 years ago," says Dr. Scerri, group leader of the Pan-African Evolution Research Group at the Max Planck Institute for the Science of Human History and lead author of the study. "That is something in the order of 8000 generations, a long time for early people to move around and explore a big space. Their movements, patterns of mixing and genetic exchanges, are what gave rise to us."
"'The genetics of contemporary humans are very clear. The greatest genetic diversity is found in Africans," explains Prof. Thomas of University College London. "The old theory that we descend from regional populations spread across the Old World over the last million years or so is not supported by genetics data. Sure, non-Africans today have some ancestry from Neanderthals, and some have appreciable ancestry from the recently discovered Denisovans. And maybe other, as yet undiscovered ancient hominin groups also interbred with us, Homo sapiens. But none of this changes the fact that more than 90 percent of the ancestry of everybody in the world lies in Africa over the last 100,000 years."
***
"'Instead of a series of population splits branching off an ancestral tree, changes in connectivity between different populations over time seem a more reasonable assumption, and appear to explain several patterns of genomic diversity not explained by current alternative models. Metapopulations are the kind of model you'd expect if people were moving around and mixing over long periods and wide geographic areas. We cannot objectively identify this geographic area today from genetic data alone, but data from other disciplines suggest that the African continent represents the most likely geographical scale."
"The scientists argue that this view is not only better supported by the fossil, genetic and archaeological evidence, it also better explains the paleoanthropological record beyond Africa.
"'We see physically diverse early human fossils from across Africa, some very old genetic lineages and a pan-African shift in technology and material culture that reflects advanced cognition, including new technical and social innovations, across the continent. In other words, what you'd expect from a dynamic interconnected patchwork of populations that were at times more or less isolated from each other," says Dr. Scerri. "This would also help to explain the increasing evidence for unexpected populations, including in areas outside Africa such as the Hobbits on Flores," she adds.
"'A metapopulation model helps us to find a way to acknowledge the paleontological, archaeological and genetic evidence for a recent African origin with limited gene flow from non-African metapopulations, such as Neanderthals, without falling into overly polemic and restrictive debates," adds Dr. Scerri. (my bold)
***
"'If we look at the available data through the lens of changes in connectivity, the record starts to make a lot more sense. We need such flexibility to be able to make sense of the past, or we get lost in a malaise of ever-increasing named species, failed trajectories and population trees that never existed," says Prof. Thomas. "Science always favors the simpler explanation and it is becoming increasingly difficult to stick to old narratives when they have to become over-complicated in order to stay relevant," he adds.
"'Our African origins cannot be denied, but we definitely don't yet have the resolution to include or exclude different bits of evidence simply because they don't fit with a particular view. We need better reasons than that," says Dr. Scerri."
Comment: the authors point is very important. Perhaps most of human evolution occurred in African populations and the outside fossils represent simply migration with local changes. This fits my concept of a purposeful God who didn't create scattered populations for no good reason, as suggested by my bolded statement in the article.
Human evolution; early ancestor probable upright posture
DAVID: Exactly. Chimps are constantly up and down for six million years and they are still chimps. There has to be driving force to create humans and the fossil changes point to preparatory, unnecessary at the time, early changes by the driving force, God.
dhw: You seem to think that all animals live under the same conditions at all times and in all places or, if there are changes, they all respond in the same way. All we know is that some of our earliest ancestors began to develop traits of bipedalism! Instead of your God saying: “I want to specially design a totally upright H. sapiens, and so I’ll start by specially designing bits and pieces that aren’t necessary yet”, I suggest we have local conditions in which particular groups of “chimps” (or whatever) find that there’s more to life than living in trees, and there are even better prospects down on the ground. Hence various species of hominids and homos over approx. 21 million years according to Dr Filler.
DAVID: A total non-answer to the point above. Dr. filler's point is mine. Why a tiny inconsequential lumbar change 21 million years ago? It didn't change the lifestyle of that monkey and wasn't necessary at that time.
How on earth do you and he know about the lifestyle of a monkey that lived 21 million years ago? Maybe the monkey spent a bit more time on the ground than in the trees because it found a greater variety of food that way, and so it had a bit of a lumbar change. And according to your theory, what exactly would have been the point of your God, whose only purpose was to design H.sapiens, specially designing a lumbar change that was of no use to the poor old monkey that underwent the operation? Ah, but of course, you have no idea why your God chose this method of “evolving” H. sapiens.
Under “Human evolution”: According to archaeologist Dr. Eleanor Scerri and geneticists Dr. Lounès Chikhi and Professor Mark Thomas, the quest for a single original location for modern humans is a wild goose chase.
Which means there were multiple locations, as in my first comment in this post, and it is perfectly reasonable to suppose that variations would have been the response to different conditions.
QUOTE: Preliminary work on the pelvis of the recently discovered 1.98 million-year-old hominin Australopithecus sediba found it to possess a unique combination of Homo and Australopithecus-like features.
dhw: All complete in themselves, but suggestive of convergent evolution as each “species” works out its own evolutionary course.
DAVID: The 'homo' features are pre-planned preparations for a full new species. And of course re' my comment, you have no answer for birth canal changes to accommodate a bigger baby head, when it involves three individuals with their individual DNA's: father, mother and baby itself.
dhw: The ‘homo’ features worked perfectly well for that particular “fully changed” “full new” species! You claim to believe in common descent, and so every single species in which there is a father, mother and baby had to coordinate their DNA to accommodate whatever changes led to speciation. You have your God dabbling or preprogramming ALL changes in advance of their being needed! In the theistic version of my hypothesis, I have your God designing the autonomous mechanism which enables the cell communities to cooperate and reconstruct themselves according to new demands as they arise.
DAVID: Cell committees cannot plan and design. That is obvious. You can invent all you want about 'my God'. I view it as pure invention, not supported by my view of a purposeful, in-control God.
In my hypothesis, cell communities react to new conditions by redesigning themselves, and we know they can do this by adapting. It is not “obvious” that they can’t achieve major changes, but that remains an open question. Once again the invention of such a mechanism would be purposeful, and it would indicate that your God deliberately chose to give evolution free rein. See “Natural Wonders and Evolution” on the subject of purpose and control.
Human evolution; early ancestor probable upright posture
by David Turell , Tuesday, September 24, 2019, 14:36 (1885 days ago) @ dhw
DAVID: A total non-answer to the point above. Dr. filler's point is mine. Why a tiny inconsequential lumbar change 21 million years ago? It didn't change the lifestyle of that monkey and wasn't necessary at that time.
dhw: How on earth do you and he know about the lifestyle of a monkey that lived 21 million years ago? Maybe the monkey spent a bit more time on the ground than in the trees because it found a greater variety of food that way, and so it had a bit of a lumbar change. And according to your theory, what exactly would have been the point of your God, whose only purpose was to design H.sapiens, specially designing a lumbar change that was of no use to the poor old monkey that underwent the operation? Ah, but of course, you have no idea why your God chose this method of “evolving” H. sapiens.
Of course I don't know the daily habits of the monkey, but I do know that slight changes in one vertebrae didn't change the animal. I t demonstrates god's pre-planning for future evolution and demonstrates God's tight control using His chosen method of creation. That I don 't question God's choices is your problem, not mine.
Under “Human evolution”: According to archaeologist Dr. Eleanor Scerri and geneticists Dr. Lounès Chikhi and Professor Mark Thomas, the quest for a single original location for modern humans is a wild goose chase.dhw: Which means there were multiple locations, as in my first comment in this post, and it is perfectly reasonable to suppose that variations would have been the response to different conditions.
The point was 90% were in Africa, not scattered all over. And your are correct, there were different conditions in all part of Africa.
QUOTE: Preliminary work on the pelvis of the recently discovered 1.98 million-year-old hominin Australopithecus sediba found it to possess a unique combination of Homo and Australopithecus-like features.dhw: All complete in themselves, but suggestive of convergent evolution as each “species” works out its own evolutionary course.
DAVID: The 'homo' features are pre-planned preparations for a full new species. And of course re' my comment, you have no answer for birth canal changes to accommodate a bigger baby head, when it involves three individuals with their individual DNA's: father, mother and baby itself.
dhw: The ‘homo’ features worked perfectly well for that particular “fully changed” “full new” species! You claim to believe in common descent, and so every single species in which there is a father, mother and baby had to coordinate their DNA to accommodate whatever changes led to speciation. You have your God dabbling or preprogramming ALL changes in advance of their being needed! In the theistic version of my hypothesis, I have your God designing the autonomous mechanism which enables the cell communities to cooperate and reconstruct themselves according to new demands as they arise.
DAVID: Cell committees cannot plan and design. That is obvious. You can invent all you want about 'my God'. I view it as pure invention, not supported by my view of a purposeful, in-control God.
dhw: In my hypothesis, cell communities react to new conditions by redesigning themselves, and we know they can do this by adapting. It is not “obvious” that they can’t achieve major changes, but that remains an open question. Once again the invention of such a mechanism would be purposeful, and it would indicate that your God deliberately chose to give evolution free rein. See “Natural Wonders and Evolution” on the subject of purpose and control.
"Free rein" in no way supports a purposeful God who knows what He wants to evolve. Sti ll humanizing God.
Human evolution; early fossils are rare
by David Turell , Tuesday, September 24, 2019, 22:47 (1885 days ago) @ David Turell
And not all findings are available for study by many experts:
https://inference-review.com/article/access-all-areas
"Paleoanthropologists reconstruct human history from scant and enigmatic traces of a distant past—often from little more than a handful of objects. The human fossils that form the basis for the discipline are hard to find and not much easier to study. In a highly competitive environment where research material, economic resources, and intellectual property rights are at stake, new discoveries are, at times, closely guarded by their finders. Competition both drives and constrains research as, perhaps inevitably, personal interests become intertwined with questions about our heritage. In recent years, the development of powerful tools for digitization and analysis have provided paleoanthropologists with new ways to preserve and circulate fossil data. For all these reasons, it is time to reconsider our current vision for paleoanthropological research and propose better procedures.
***
"the identification of a new human species was often a complicated and drawn-out process. First proposed in 1863, the notion of Homo neanderthalensis as a distinct species of archaic humans was only embraced at the beginning of the twentieth century after numerous additional specimens had been found. Similarly, Homo erectus and Australopithecus africanus were not widely accepted in the field for several decades after being described in 1894 and 1925, respectively. Even in the last 30 years, the identification of the oldest known hominids—Ardipithecus ramidus, Sahelanthropus tchadensis, and Orrorin tugenensis—has been the subject of vigorous debate among paleoanthropologists. The same is also true for the identification of Homo floresiensis and, more recently, Homo naledi.
***
"For decades, the oldest fossils attributed to Homo sapiens were the remains found between 1967 and 1974 at the Omo Kibish site in Ethiopia and dated to 195,000 years ago. The oldest found outside Africa were those unearthed at Qafzeh in Israel and dated to 90,000 years ago. In 2017, specimens found at the Jebel Irhoud site in Morocco were re-dated to roughly 280,000 to 350,000 years ago.3 The following year, a fossil from the Misliya site in Israel was dated to between 177,000 and 194,000 years ago.
***
"Another limitation involves the conservation and sharing of data. The question of ownership, not to mention the management of data, is far from straightforward in some countries. Ideally, custodian institutions would be responsible for generating the raw digital data for the objects in their collections. In France, imagery obtained for scientific research is free of copyright since it is an objective replica of a specimen, without any artistic or personal contribution. All the tomographic data generated from the anthropological collections of the Muséum national d’histoire naturelle in Paris are available for any scientific project.
***
"Long-held paleoanthropological conventions were turned on their head following the discovery of Homo naledi in South Africa in 2013. This was a significant discovery for numerous reasons, chief among them being the age of the fossils. The specimens are relatively recent, dating from around 300,000 years ago, yet they possess anatomical characteristics reminiscent of the very first members of the genus Homo—the skull of naledi has similarities to that of habilis, which lived two million years ago. The identification of a species with such ancient features that lived almost at the same time as Homo sapiens and Neanderthals was a stunning development.
***
"Since the first papers announcing the discovery were published, there have been numerous studies that have fleshed out the initial descriptions. Still, the novel approaches and speed with which Homo naledi was presented to the field proved polarizing. The way the discovery was handled has been the subject of much debate and generated considerable criticism. Judging from earlier discoveries, this mixed reception should come as no surprise. Such a significant announcement will also inevitably overshadow other specimens and hypotheses, particularly when accompanied by widespread media coverage.
"In contrast to the Homo naledi specimens, the fossils of other species that might form the basis for worthwhile comparisons, are accessible only to varying degrees and in some cases not at all. An exhaustive comparative study would be impossible for the simple reason that access to the material from other important discoveries is often limited to just a few tens of specimens. It is for this reason that the release of the high-resolution Homo naledi scans is an event, in my view, almost as striking as the announcement of the new species and represents a significant milestone in the development of the field."
Comment: No wonder H. sapiens ancestry is so confusing. Expect many more specimens before it clears up.
Human evolution; early ancestor probable upright posture
DAVID: Dr. filler's point is mine. Why a tiny inconsequential lumbar change 21 million years ago? It didn't change the lifestyle of that monkey and wasn't necessary at that time.
dhw: How on earth do you and he know about the lifestyle of a monkey that lived 21 million years ago? Maybe the monkey spent a bit more time on the ground than in the trees because it found a greater variety of food that way, and so it had a bit of a lumbar change. […]
DAVID: Of course I don't know the daily habits of the monkey, but I do know that slight changes in one vertebrae didn't change the animal. It demonstrates god's pre-planning for future evolution and demonstrates God's tight control using His chosen method of creation.
So 21 million years ago your always-in-total-control God, whose only purpose was to design H. sapiens, went to all the trouble of specially changing one vertebra, which was of no use whatsoever to the monkey concerned, but this demonstrates his chosen method of designing the only thing he wanted to design. No wonder you have no idea why he chose such a method!
DAVID: That I don't question God's choices is your problem, not mine.
Once more: my problem is that you don’t question your INTERPRETATION of his choice of purpose and method!
Under “Human evolution”: According to archaeologist Dr. Eleanor Scerri and geneticists Dr. Lounès Chikhi and Professor Mark Thomas, the quest for a single original location for modern humans is a wild goose chase.
dhw: Which means there were multiple locations, […] and it is perfectly reasonable to suppose that variations would have been the response to different conditions.
DAVID: The point was 90% were in Africa, not scattered all over. And you are correct, there were different conditions in all part of Africa.
And so, I repeat, it is perfectly reasonable to suppose that the variations would have been the response to different conditions, as opposed to your God specially designing all of them in anticipation of different conditions and as steps along the way to specially designing the only species he wanted to create.
DAVID: Cell committees cannot plan and design. That is obvious. You can invent all you want about 'my God'. I view it as pure invention, not supported by my view of a purposeful, in-control God.
dhw: In my hypothesis, cell communities react to new conditions by redesigning themselves, and we know they can do this by adapting. It is not “obvious” that they can’t achieve major changes, but that remains an open question. Once again the invention of such a mechanism would be purposeful, and it would indicate that your God deliberately chose to give evolution free rein.
DAVID: "Free rein" in no way supports a purposeful God who knows what He wants to evolve. Still humanizing God.
Free rein supports the idea that a purposeful God’s purpose was the higgledy-piggledy bush which constitutes the history of life on Earth. The higgledy-piggledy bush ”in no way” supports the idea that from the very beginning God only wanted one species and yet was in total control of every branch!
DAVID: (under “early fossils”) No wonder H. sapiens ancestry is so confusing. Expect many more specimens before it clears up.
No wonder you have no idea why your always-in-control God would specially design all these confusingly different specimens when all he wanted was just one.
Human evolution; early ancestor probable upright posture
by David Turell , Wednesday, September 25, 2019, 19:23 (1884 days ago) @ dhw
DAVID: Of course I don't know the daily habits of the monkey, but I do know that slight changes in one vertebrae didn't change the animal. It demonstrates god's pre-planning for future evolution and demonstrates God's tight control using His chosen method of creation.
dhw: So 21 million years ago your always-in-total-control God, whose only purpose was to design H. sapiens, went to all the trouble of specially changing one vertebra, which was of no use whatsoever to the monkey concerned, but this demonstrates his chosen method of designing the only thing he wanted to design. No wonder you have no idea why he chose such a method!
The definition of evolution is a change from one form to another, or have you forgotten? Progress has to be designed in my view , and in the fossil record are small changes and large gaps. Most species changes are after large gaps in form or physiology but obviously some are small. And as before, its not that I have 'no idea', I don't question God's choice to evolve all forms.
DAVID: That I don't question God's choices is your problem, not mine.
dhw: Once more: my problem is that you don’t question your INTERPRETATION of his choice of purpose and method!
Why should I? You are the one who has trouble with it, because it doesn't humanize God as much as you wish.
Under “Human evolution”: According to archaeologist Dr. Eleanor Scerri and geneticists Dr. Lounès Chikhi and Professor Mark Thomas, the quest for a single original location for modern humans is a wild goose chase.dhw: Which means there were multiple locations, […] and it is perfectly reasonable to suppose that variations would have been the response to different conditions.
DAVID: The point was 90% were in Africa, not scattered all over. And you are correct, there were different conditions in all part of Africa.
dhw: And so, I repeat, it is perfectly reasonable to suppose that the variations would have been the response to different conditions, as opposed to your God specially designing all of them in anticipation of different conditions and as steps along the way to specially designing the only species he wanted to create.
See the website below to understand that Neanderthal genes affect our skin and immunity and are beneficial to us. A wise God would let various homo types to contribute to the final sapiens product by developing different appropriate responses to a variety of environmental issues:
https://www.the-scientist.com/features/neanderthal-dna-in-modern-human-genomes-is-not-s...
"In the past five years, a flurry of research has sought to answer that question. Genomic analyses have associated Neanderthal variants with differences in the expression levels of diverse genes and of phenotypes ranging from skin and hair color to immune function and neuropsychiatric disease. But researchers cannot yet say how these archaic sequences affect people today, much less the humans who acquired them some 50,000–55,000 years ago."
DAVID: "Free rein" in no way supports a purposeful God who knows what He wants to evolve. Still humanizing God.
dhw: Free rein supports the idea that a purposeful God’s purpose was the higgledy-piggledy bush which constitutes the history of life on Earth. The higgledy-piggledy bush ”in no way” supports the idea that from the very beginning God only wanted one species and yet was in total control of every branch!
Of course it does! The bush supplies energy for evolution to continue under God's guidance.
DAVID: (under “early fossils”) No wonder H. sapiens ancestry is so confusing. Expect many more specimens before it clears up.dhw: No wonder you have no idea why your always-in-control God would specially design all these confusingly different specimens when all he wanted was just one.
Note the website above and what it explains about interbreeding results.
Human evolution; early ancestor probable upright posture
DAVID: The definition of evolution is a change from one form to another, or have you forgotten? Progress has to be designed in my view , and in the fossil record are small changes and large gaps. Most species changes are after large gaps in form or physiology but obviously some are small. And as before, its not that I have 'no idea', I don't question God's choice to evolve all forms.
Since we both believe evolution happened, the disagreement is not over what evolution means but over your explanation of your God’s thinking! And you use every means possible to avoid combining the two irreconcilable parts of your theory: yes, if God exists, he chose to evolve all forms. No, evolve does not mean specially design, and no, evolve all forms does not mean that his one and only purpose was to specially design H. sapiens, but he decided not to do so for 3.X billion years and therefore had to specially design all the other forms in order to cover the time he had decided to take.
DAVID: That I don't question God's choices is your problem, not mine.
dhw: Once more: my problem is that you don’t question your INTERPRETATION of his choice of purpose and method!
DAVID: Why should I? You are the one who has trouble with it, because it doesn't humanize God as much as you wish.
I have trouble with it because it offers an interpretation of your God’s purpose and method which even you find illogical (you have “no idea” why he would choose this way of fulfilling his one and only purpose). The illogicality of your explanation is not justified by complaining that a logical explanation entails using human logic!
dhw: …it is perfectly reasonable to suppose that the variations would have been the response to different conditions, as opposed to your God specially designing all of them in anticipation of different conditions and as steps along the way to specially designing the only species he wanted to create.
DAVID: See the website below to understand that Neanderthal genes affect our skin and immunity and are beneficial to us. A wise God would let various homo types to contribute to the final sapiens product by developing different appropriate responses to a variety of environmental issues:
None of this justifies the illogicality of the bolded part of your theory above, and I still don’t know why you think an always-in-control God found it necessary to specially design H. sapiens by first designing umpteen different hominids and homos, with a useless 21-million- year-old vertebra here and a Neanderthal gene there. In any case, you now give us a quote which leaves wide open the effect of these genes on people today:
“But researchers cannot yet say how these archaic sequences affect people today, much less the humans who acquired them some 50,000–55,000 years ago."
DAVID: "Free rein" in no way supports a purposeful God who knows what He wants to evolve. Still humanizing God.
dhw: Free rein supports the idea that a purposeful God’s purpose was the higgledy-piggledy bush which constitutes the history of life on Earth. The higgledy-piggledy bush ”in no way” supports the idea that from the very beginning God only wanted one species and yet was in total control of every branch!
DAVID: Of course it does! The bush supplies energy for evolution to continue under God's guidance.
How does that come to mean that his sole purpose was to specially design H. sapiens? All it means is that so long as there is life, there is life! “Under God’s guidance” merely repeats your fixed belief that he specially designed every branch of the bush.
Human evolution; early ancestor probable upright posture
by David Turell , Thursday, September 26, 2019, 19:43 (1883 days ago) @ dhw
DAVID: The definition of evolution is a change from one form to another, or have you forgotten? Progress has to be designed in my view , and in the fossil record are small changes and large gaps. Most species changes are after large gaps in form or physiology but obviously some are small. And as before, its not that I have 'no idea', I don't question God's choice to evolve all forms.
dhw: Since we both believe evolution happened, the disagreement is not over what evolution means but over your explanation of your God’s thinking! And you use every means possible to avoid combining the two irreconcilable parts of your theory: yes, if God exists, he chose to evolve all forms. No, evolve does not mean specially design, and no, evolve all forms does not mean that his one and only purpose was to specially design H. sapiens, but he decided not to do so for 3.X billion years and therefore had to specially design all the other forms in order to cover the time he had decided to take.
My meaning of the word evolve, since you brought up the word's meaning, is that new complexities developed from past complexities creating a process that advanced complexity. We differ in that I firmly think God guided the process and in doing so He actually designed what required design and gave organisms the epigenetic ability for minor adaptations. As for humans, we are such an unusual result they are an obvious goal of evolution. I am not confused about God's thinking, since I believe what happened is God's doing as Creator. He obviously chose to evolve humans over time.
dhw: I have trouble with it because it offers an interpretation of your God’s purpose and method which even you find illogical (you have “no idea” why he would choose this way of fulfilling his one and only purpose). The illogicality of your explanation is not justified by complaining that a logical explanation entails using human logic!
dhw: …it is perfectly reasonable to suppose that the variations would have been the response to different conditions, as opposed to your God specially designing all of them in anticipation of different conditions and as steps along the way to specially designing the only species he wanted to create.
Having no idea as to why God made His choice to evolve humans, means only that
I cannot know His reasons, only guess at them, and therefore is a totally logical position.
dhw: None of this justifies the illogicality of the bolded part of your theory above, and I still don’t know why you think an always-in-control God found it necessary to specially design H. sapiens by first designing umpteen different hominids and homos, with a useless 21-million- year-old vertebra here and a Neanderthal gene there. In any case, you now give us a quote which leaves wide open the effect of these genes on people today:“But researchers cannot yet say how these archaic sequences affect people today, much less the humans who acquired them some 50,000–55,000 years ago."
What a wild assumption. The researchers know the genes exist, but how much they affect us is still under current investigation, not that they are probably valueless as you imply.
DAVID: "Free rein" in no way supports a purposeful God who knows what He wants to evolve. Still humanizing God.dhw: Free rein supports the idea that a purposeful God’s purpose was the higgledy-piggledy bush which constitutes the history of life on Earth. The higgledy-piggledy bush ”in no way” supports the idea that from the very beginning God only wanted one species and yet was in total control of every branch!
DAVID: Of course it does! The bush supplies energy for evolution to continue under God's guidance.
dhw: How does that come to mean that his sole purpose was to specially design H. sapiens? All it means is that so long as there is life, there is life! “Under God’s guidance” merely repeats your fixed belief that he specially designed every branch of the bush.
Have you forgotten the argument that we humans are so special we must be his final purpose, as Adler argues from his position as a believer philosopher. You can't ignore it!
Human evolution; early ancestor probable upright posture
DAVID: The definition of evolution is a change from one form to another, or have you forgotten? […] And as before, its not that I have 'no idea', I don't question God's choice to evolve all forms.
dhw: Since we both believe evolution happened, the disagreement is not over what evolution means but over your explanation of your God’s thinking! And you use every means possible to avoid combining the two irreconcilable parts of your theory. […]
DAVID: My meaning of the word evolve, since you brought up the word's meaning, is that new complexities developed from past complexities creating a process that advanced complexity. We differ in that I firmly think God guided the process and in doing so He actually designed what required design and gave organisms the epigenetic ability for minor adaptations.
“Guided the process” means that he either preprogrammed or personally dabbled every innovation, not to mention every lifestyle (e.g. the monarch butterfly) and natural wonder (e.g. the weaverbird’s nest), which you insist were also specially designed. Since you are now distinguishing between actual design (preprogramming and/or dabbling) and “epigenetic ability”, I can only assume that the latter means he gave autonomous intelligence to all organisms. If it was not autonomous, then it was still “guided”, i.e. preprogrammed or dabbled. Firstly, this autonomy can also apply to bacteria, and secondly this is the mechanism which I call cellular intelligence and which may also have directed evolution, though that remains an unproven hypothesis. Just trying to clarify. Any disagreement with this interpretation of your statement?
DAVID: As for humans, we are such an unusual result they are an obvious goal of evolution. I am not confused about God's thinking, since I believe what happened is God's doing as Creator. He obviously chose to evolve humans over time.
Yet again you try to separate and even change the different parts of your theory in order to hide the illogicality of their COMBINATION. Firstly, you’ve gone back to “AN obvious goal” as if there were others, but you insist that the goal of all preceding life forms extant and extinct was to provide food to keep life going because he had decided – for reasons you cannot fathom – to wait 3.X billion years before he started designing all the life forms that led to the only one he wanted. But secondly, even if it were true that his one and only goal was to produce H. sapiens, you refuse to consider any logical explanation of the delay (e.g. experimentation), and so you believe he “had to” abide by the procedure bolded above, because you happen to know that he is in total control and he cannot possibly have any characteristics (such as the desire to experiment) in common with the humans you say he specially created.
dhw: The illogicality of your explanation is not justified by complaining that a logical explanation entails using human logic!
DAVID: Having no idea as to why God made His choice to evolve humans, means only that I cannot know His reasons, only guess at them, and therefore is a totally logical position.
How can not knowing his reasons but making a guess which you yourself cannot explain (you have no idea why) be called a totally logical position?
dhw: […] I still don’t know why you think an always-in-control God found it necessary to specially design H. sapiens by first designing umpteen different hominids and homos, with a useless 21-million- year-old vertebra here and a Neanderthal gene there. In any case, you now give us a quote which leaves wide open the effect of these genes on people today:
“But researchers cannot yet say how these archaic sequences affect people today, much less the humans who acquired them some 50,000–55,000 years ago."
DAVID: What a wild assumption. The researchers know the genes exist, but how much they affect us is still under current investigation, not that they are probably valueless as you imply.
It was you who wrote that the “tiny inconsequential lumbar change 21 million years ago […] didn’t change the lifestyle of that monkey and wasn’t necessary at that time”, which I take to mean valueless. And it was you who wrote: “Neanderthal genes affect our skin and immunity and are beneficial to us. A wise God would let various homo types to contribute to the final sapiens product by developing different appropriate responses to a variety of environmental issues”. What a “wild assumption”, when the researchers themselves leave such claims wide open.
Human evolution; early ancestor probable upright posture
by David Turell , Friday, September 27, 2019, 22:28 (1882 days ago) @ dhw
DAVID: My meaning of the word evolve, since you brought up the word's meaning, is that new complexities developed from past complexities creating a process that advanced complexity. We differ in that I firmly think God guided the process and in doing so He actually designed what required design and gave organisms the epigenetic ability for minor adaptations.
“Guided the process” means that he either preprogrammed or personally dabbled every innovation, not to mention every lifestyle (e.g. the monarch butterfly) and natural wonder (e.g. the weaverbird’s nest), which you insist were also specially designed. Since you are now distinguishing between actual design (preprogramming and/or dabbling) and “epigenetic ability”, I can only assume that the latter means he gave autonomous intelligence to all organisms. If it was not autonomous, then it was still “guided”, i.e. preprogrammed or dabbled. Firstly, this autonomy can also apply to bacteria, and secondly this is the mechanism which I call cellular intelligence and which may also have directed evolution, though that remains an unproven hypothesis. Just trying to clarify. Any disagreement with this interpretation of your statement?
epigenetic means nothing more than minor necessary adaptations. Otherwise OK.
DAVID: As for humans, we are such an unusual result they are an obvious goal of evolution. I am not confused about God's thinking, since I believe what happened is God's doing as Creator. He obviously chose to evolve humans over time.
dhw: Yet again you try to separate and even change the different parts of your theory in order to hide the illogicality of their COMBINATION. Firstly, you’ve gone back to “AN obvious goal” as if there were others, but you insist that the goal of all preceding life forms extant and extinct was to provide food to keep life going because he had decided – for reasons you cannot fathom – to wait 3.X billion years before he started designing all the life forms that led to the only one he wanted.
The humans were not the only thing He wanted. he knew He needed the entire bush of life as support for the time evolution took. Humans were his final goal, and I firmly believe we are last.
dhw: But secondly, even if it were true that his one and only goal was to produce H. sapiens, you refuse to consider any logical explanation of the delay (e.g. experimentation), and so you believe he “had to” abide by the procedure bolded above, because you happen to know that he is in total control and he cannot possibly have any characteristics (such as the desire to experiment) in common with the humans you say he specially created.
He very well could think like us, but it is only a guess, as your suppositions about His thoughts are..
dhw: How can not knowing his reasons but making a guess which you yourself cannot explain (you have no idea why) be called a totally logical position?
I don't try to explain. I just accept what He created
dhw: […] I still don’t know why you think an always-in-control God found it necessary to specially design H. sapiens by first designing umpteen different hominids and homos, with a useless 21-million- year-old vertebra here and a Neanderthal gene there. In any case, you now give us a quote which leaves wide open the effect of these genes on people today:
“But researchers cannot yet say how these archaic sequences affect people today, much less the humans who acquired them some 50,000–55,000 years ago."
DAVID: What a wild assumption. The researchers know the genes exist, but how much they affect us is still under current investigation, not that they are probably valueless as you imply.
dhw: It was you who wrote that the “tiny inconsequential lumbar change 21 million years ago […] didn’t change the lifestyle of that monkey and wasn’t necessary at that time”, which I take to mean valueless.
Not valueless, but a tiny astep toward the anticipated future.
dhw: And it was you who wrote: “Neanderthal genes affect our skin and immunity and are beneficial to us. A wise God would let various homo types to contribute to the final sapiens product by developing different appropriate responses to a variety of environmental issues”. What a “wild assumption”, when the researchers themselves leave such claims wide open.
They assume there are such benefits as they noted. You are struggling to argue.
Human evolution; early ancestor probable upright posture
dhw: Since you are now distinguishing between actual design (preprogramming and/or dabbling) and “epigenetic ability”, I can only assume that the latter means he gave autonomous intelligence to all organisms. If it was not autonomous, then it was still “guided”, i.e. preprogrammed or dabbled. Firstly, this autonomy can also apply to bacteria, and secondly this is the mechanism which I call cellular intelligence and which may also have directed evolution, though that remains an unproven hypothesis. Just trying to clarify. Any disagreement with this interpretation of your statement?
DAVID: epigenetic means nothing more than minor necessary adaptations. Otherwise OK.
We are making progress. You agree that your God (if he exists) gave organisms (cell communities) a degree of autonomous intelligence, but only to design minor adaptations. This autonomous intelligence can also be present in bacteria. The question then becomes where we draw the line between minor and major adaptations, and between major adaptations and innovations. The hypothesis I offer – just as unproven as your hypothesis of divine preprogramming/dabbling – is that the same mechanism is capable of designing all of them. Just clarifying again.
DAVID: The humans were not the only thing He wanted. he knew He needed the entire bush of life as support for the time evolution took. Humans were his final goal, and I firmly believe we are last.
In your theory, it wasn’t evolution that “took time” but your God who for some inexplicable reason DECIDED to wait 3.X billion years before starting to “evolve” (= specially design) the only thing he wanted to design, which was us. And he NEEDED (very different from “wanted”) the entire bush to COVER that time! Why do you keep ignoring your own precise account of the process: “He knew those designs were required interim goals to establish the necessary food supply to cover the time he knew he had decided to take.”
dhw: But secondly, even if it were true that his one and only goal was to produce H. sapiens, you refuse to consider any logical explanation of the delay (e.g. experimentation), and so you believe he “had to” abide by the procedure bolded above, because you happen to know that he is in total control and he cannot possibly have any characteristics (such as the desire to experiment) in common with the humans you say he specially created.
DAVID: He very well could think like us, but it is only a guess, as your suppositions about His thoughts are.
Of course it’s a guess, just like the whole of your theory, bolded above, and what’s more yours is a guess which you yourself find inexplicable: “Haven’t you realized by now, I have no idea why God chose to evolve humans over time?” More importantly, since you now recognize that your God may very well think like us, please stop dismissing logical explanations purely on the grounds that you believe your God does NOT think like us.
dhw: […] I still don’t know why you think an always-in-control God found it necessary to specially design H. sapiens by first designing umpteen different hominids and homos, with a useless 21-million- year-old vertebra here and a Neanderthal gene there.
DAVID: What a wild assumption. The researchers know the genes exist, but how much they affect us is still under current investigation, not that they are probably valueless as you imply.
dhw: It was you who wrote that the “tiny inconsequential lumbar change 21 million years ago […] didn’t change the lifestyle of that monkey and wasn’t necessary at that time”, which I take to mean valueless.
DAVID: Not valueless, but a tiny step toward the anticipated future.
You introduced the word “valueless”. I used the word "useless", which I think sums up inconsequential, not necessary, and not changing anything. And I still don’t understand why a God, who according to you can produce whole organs and organisms with a single dabble, should choose to dabble one single, useless vertebra to “anticipate” what he is going to design in the future.
dhw: And it was you who wrote: Neanderthal genes affect our skin and immunity and are beneficial to us. A wise God would let various homo types to contribute to the final sapiens product by developing different appropriate responses to a variety of environmental issues."
DAVID: They assume there are such benefits as they noted. You are struggling to argue.
They make no such assumption: “But researchers cannot yet say how these archaic sequences affect people today, much less the humans who acquired them some 50,000–55,000 years ago." Besides, why couldn't a totally-in-control God enable the only desired species to develop different responses etc.? Oh, but I mustn't ask such questions, because although God might very well think like humans, you happen to know that he doesn't.
Human evolution; early ancestor probable upright posture
by David Turell , Saturday, September 28, 2019, 15:45 (1881 days ago) @ dhw
DAVID: epigenetic means nothing more than minor necessary adaptations. Otherwise OK.
dhw: We are making progress. You agree that your God (if he exists) gave organisms (cell communities) a degree of autonomous intelligence, but only to design minor adaptations. This autonomous intelligence can also be present in bacteria. The question then becomes where we draw the line between minor and major adaptations, and between major adaptations and innovations. The hypothesis I offer – just as unproven as your hypothesis of divine preprogramming/dabbling – is that the same mechanism is capable of designing all of them. Just clarifying again.
No progress. Epigenetics does not cause a new species. Something else must do it.
DAVID: The humans were not the only thing He wanted. he knew He needed the entire bush of life as support for the time evolution took. Humans were his final goal, and I firmly believe we are last.dhw: In your theory, it wasn’t evolution that “took time” but your God who for some inexplicable reason DECIDED to wait 3.X billion years before starting to “evolve” (= specially design) the only thing he wanted to design, which was us.
Not my theory at all. History tells us how long evolution took, and God used that mechanism.
dhw: And he NEEDED (very different from “wanted”) the entire bush to COVER that time! Why do you keep ignoring your own precise account of the process: “He knew those designs were required interim goals to establish the necessary food supply to cover the time he knew he had decided to take.”
Of course!
dhw: But secondly, even if it were true that his one and only goal was to produce H. sapiens, you refuse to consider any logical explanation of the delay (e.g. experimentation), and so you believe he “had to” abide by the procedure bolded above, because you happen to know that he is in total control and he cannot possibly have any characteristics (such as the desire to experiment) in common with the humans you say he specially created.
My God does not need to experiment. His creations are quite complex: quantum mechanism and the origin of consciousness
DAVID: He very well could think like us, but it is only a guess, as your suppositions about His thoughts are.
dhw: Of course it’s a guess, just like the whole of your theory, bolded above, and what’s more yours is a guess which you yourself find inexplicable: “Haven’t you realized by now, I have no idea why God chose to evolve humans over time?” More importantly, since you now recognize that your God may very well think like us, please stop dismissing logical explanations purely on the grounds that you believe your God does NOT think like us.
Thank you, pure guesswork is poor support of theory.
dhw: It was you who wrote that the “tiny inconsequential lumbar change 21 million years ago […] didn’t change the lifestyle of that monkey and wasn’t necessary at that time”, which I take to mean valueless.
DAVID: Not valueless, but a tiny step toward the anticipated future.
dhw: You introduced the word “valueless”. I used the word "useless", which I think sums up inconsequential, not necessary, and not changing anything. And I still don’t understand why a God, who according to you can produce whole organs and organisms with a single dabble, should choose to dabble one single, useless vertebra to “anticipate” what he is going to design in the future.
Just admit it, you don't under stand your humanized God at all.
dhw: And it was you who wrote: Neanderthal genes affect our skin and immunity and are beneficial to us. A wise God would let various homo types to contribute to the final sapiens product by developing different appropriate responses to a variety of environmental issues."DAVID: They assume there are such benefits as they noted. You are struggling to argue.
dhw: They make no such assumption: “But researchers cannot yet say how these archaic sequences affect people today, much less the humans who acquired them some 50,000–55,000 years ago." Besides, why couldn't a totally-in-control God enable the only desired species to develop different responses etc.? Oh, but I mustn't ask such questions, because although God might very well think like humans, you happen to know that he doesn't.
When God chose to evolve, He also used interbreeding. History shows his obvious methods. History of creation tells us how God did it, but you constantly ignore the history, whiole humanizing God's thinking
Human evolution; early ancestor probable upright posture
dhw: We are making progress. You agree that your God (if he exists) gave organisms (cell communities) a degree of autonomous intelligence, but only to design minor adaptations. […] The hypothesis I offer – just as unproven as your hypothesis of divine preprogramming/dabbling – is that the same mechanism is capable of designing all of them.
DAVID: No progress. Epigenetics does not cause a new species. Something else must do it.
We don’t know what causes speciation, and since the process has stopped for what has been a relatively short period in geological terms, we cannot observe it. But now that you have agreed that your God must have given organisms sufficient autonomous intelligence to create small modifications, we have a basis for suggesting that the same autonomous intelligence might be capable of effecting large modifications. I have agreed that it is unproven, as is your own theory.
DAVID: The humans were not the only thing He wanted. he knew He needed the entire bush of life as support for the time evolution took. Humans were his final goal, and I firmly believe we are last.
dhw: In your theory, it wasn’t evolution that “took time” but your God who for some inexplicable reason DECIDED to wait 3.X billion years before starting to “evolve” (= specially design) the only thing he wanted to design, which was us.
DAVID: Not my theory at all. History tells us how long evolution took, and God used that mechanism.
We know how long evolution has taken so far, and if God exists, then he used the mechanisms of evolution, but you have added all the bits and pieces above and below. You claim here that it is not your theory, and below you say of course it is your theory.
dhw: And he NEEDED (very different from “wanted”) the entire bush to COVER that time! Why do you keep ignoring your own precise account of the process: “He knew those designs were required interim goals to establish the necessary food supply to cover the time he knew he had decided to take.”
DAVID: Of course!
Do please make up your mind. And let us not forget that you have no idea why he decided to “evolve humans over time” as described in your theory.
dhw: […] you happen to know that he is in total control and he cannot possibly have any characteristics (such as the desire to experiment) in common with the humans you say he specially created.
DAVID: My God does not need to experiment. His creations are quite complex: quantum mechanism and the origin of consciousness
So how does the complexity and the origin of consciousness support your statement that he did not need to experiment in order to create them? If, as you claim, his only goal was to produce H. sapiens, experimentation would explain why it took him so much time – as opposed to him knowing how to do it but for some unknown reason deciding not to do it for 3.X billion years!
dhw: I still don’t understand why a God, who according to you can produce whole organs and organisms with a single dabble, should choose to dabble one single, useless vertebra to “anticipate” what he is going to design in the future.
DAVID: Just admit it, you don't understand your humanized God at all.
It is, of course, your version of God that I do not understand. My alternative versions are perfectly understandable, even to you, since you admit that you see them as logical. Your objection is that you believe your God is NOT logical by human standards! But let’s try once more: do please explain why you think he chose to dabble one single useless vertebra 21 million years ago if he is capable of producing major adaptations with a single dabble (e.g. see the post about whales).
dhw […] why couldn't a totally-in-control God enable the only desired species to develop different responses etc.? Oh, but I mustn't ask such questions, because although God might very well think like humans, you happen to know that he doesn't.
DAVID: When God chose to evolve, He also used interbreeding. History shows his obvious methods. History of creation tells us how God did it, but you constantly ignore the history, while humanizing God's thinking
I have never ignored the history, and you have agreed that all my different hypotheses fit in with the history. The illogicality of your theory is not suddenly made logical by your attacking other theories. I am happy to acknowledge that all my own alternatives are what you call guesses, but since you have agreed that your God “very well could think like us”, there really is no point in your harping on about my logical explanations “humanizing” him. One or other of my explanations might “very well” be right!
Human evolution; early ancestor probable upright posture
by David Turell , Sunday, September 29, 2019, 18:57 (1880 days ago) @ dhw
DAVID: Not my theory at all. History tells us how long evolution took, and God used that mechanism.
dhw: We know how long evolution has taken so far, and if God exists, then he used the mechanisms of evolution, but you have added all the bits and pieces above and below. You claim here that it is not your theory, and below you say of course it is your theory.
All I was saying is that your interpretation of my theory is not my theory.
dhw: And he NEEDED (very different from “wanted”) the entire bush to COVER that time! Why do you keep ignoring your own precise account of the process: “He knew those designs were required interim goals to establish the necessary food supply to cover the time he knew he had decided to take.”DAVID: Of course!
dhw: Do please make up your mind. And let us not forget that you have no idea why he decided to “evolve humans over time” as described in your theory.
Same Theory: God, the Creator, created evolution as His choice of life's creation. Obvious logical result of accepting God as Creator.
dhw: […] you happen to know that he is in total control and he cannot possibly have any characteristics (such as the desire to experiment) in common with the humans you say he specially created.
DAVID: My God does not need to experiment. His creations are quite complex: quantum mechanism and the origin of consciousness
dhw: So how does the complexity and the origin of consciousness support your statement that he did not need to experiment in order to create them? If, as you claim, his only goal was to produce H. sapiens, experimentation would explain why it took him so much time – as opposed to him knowing how to do it but for some unknown reason deciding not to do it for 3.X billion years!
Experimentation strongly implies a humanized God. God knows what He is doing, and makes His own clear Choices.
dhw: I still don’t understand why a God, who according to you can produce whole organs and organisms with a single dabble, should choose to dabble one single, useless vertebra to “anticipate” what he is going to design in the future.
DAVID: Just admit it, you don't understand your humanized God at all.
dhw: It is, of course, your version of God that I do not understand. My alternative versions are perfectly understandable, even to you, since you admit that you see them as logical. Your objection is that you believe your God is NOT logical by human standards! But let’s try once more: do please explain why you think he chose to dabble one single useless vertebra 21 million years ago if he is capable of producing major adaptations with a single dabble (e.g. see the post about whales).
All I see is a God who uses small and large changes as He wishes. All you see is a human puzzled God.
dhw […] why couldn't a totally-in-control God enable the only desired species to develop different responses etc.? Oh, but I mustn't ask such questions, because although God might very well think like humans, you happen to know that he doesn't.
DAVID: When God chose to evolve, He also used interbreeding. History shows his obvious methods. History of creation tells us how God did it, but you constantly ignore the history, while humanizing God's thinking
dhw: I have never ignored the history, and you have agreed that all my different hypotheses fit in with the history. The illogicality of your theory is not suddenly made logical by your attacking other theories. I am happy to acknowledge that all my own alternatives are what you call guesses, but since you have agreed that your God “very well could think like us”, there really is no point in your harping on about my logical explanations “humanizing” him. One or other of my explanations might “very well” be right!
Your hypotheses fit a humanized God, and therefore are logical for that view of God.
Human evolution; early ancestor probable upright posture
by David Turell , Monday, September 12, 2022, 18:23 (801 days ago) @ David Turell
Our unique pelvis:
https://phys.org/news/2022-09-humans-upright-secret-pelvis.html
"If evolutionary biologist Terence D. Capellini were to rank the body parts that make us quintessentially human, the pelvis would place close to the top.
"After all, its design makes it possible for humans to walk upright on two legs (unlike our primate cousins) and it makes it possible for mothers to give birth to babies with large heads (therefore big brains). On an anatomical level, the pelvis is well understood, but that knowledge starts to break down when it comes to how and when this uber-important structure takes its shape during development.
"A new study from Capellini's lab is changing that. Published in Science Advances, the work shows when during pregnancy the pelvis takes shape and identifies the genes and genetic sequences that orchestrate the process.
***
"'This paper is really focused on what all humans share, which are these changes to the pelvis that allowed us to walk on two legs and allowed us to give birth to a large fetal head," said Capellini, a newly tenured Professor in the Department of Human Evolutionary Biology and senior author on the study.
"The study shows that many of the features essential for human walking and birth form around the 6- to 8-week mark during pregnancy. This includes key pelvic features unique to humans, like its curved and basin-like shape. The formation happens while bones are still cartilage so they can easily, curve, rotate, expand, and grow.
"The researchers also saw that as other cartilage in the body begins to turn into bone this developing pelvic section stays as cartilage longer, so it has time to form properly.
"'There appears to be a stalling that happens and this stalling allows the cartilage to still grow, which was pretty interesting to find and surprising," Capellini said. "I call it a zone of protection."
***
"The researchers performed RNA sequencing to show which genes in the region are actively triggering the formation of the pelvis and are stalling ossification, which normally turns softer cartilage to hard bone. They identified hundreds of genes that are turned either on or off during the 6- to 8-week mark to form the ilium in the pelvis, the largest and uppermost bones of the hip with blade-like structures that curve and rotate into a basin to support walking on two legs."
Compared to chimpanzees and gorillas, the shorter and wider reorientation of our pelvic blades make it so humans don't have to shift the mass of our weight forward and use our knuckles to walk or balance more comfortably. It also helps increase the size of the birth canal. Apes on the other hand have much narrower birth canals and more elongated ilium bones.
Comment: we may look like apes, but the differences are not superficial
Human evolution; ncRNA drove brain evolution
by David Turell , Tuesday, September 13, 2022, 17:01 (800 days ago) @ David Turell
Research still in its infancy:
https://www.the-scientist.com/features/the-noncoding-regulators-of-the-brain-70457?utm_...
"When the Human Genome Project published the first draft of the human genome sequence in 2001, "many researchers expected to be able to pinpoint protein alterations that would explain the distinctive features of human brains compared to those of other animals—larger size relative to the body, increased neuronal connectivity, and other contributors to our superior cognitive complexity. Instead, “it was frustrating to see how few protein-coding genes exist,” says Geraldine Zimmer-Bensch, a neuroepigeneticist at Rheinisch-Westfälische Technische Hochschule Aachen in Germany, “and even more frustrating, how little difference there is between the mouse and the human protein-coding genome.” Yes, there are proteins and variants of proteins that are unique to our species, she says, but there simply aren’t enough of them to explain humans’ singular cognitive prowess.
"This was particularly surprising because at least a tenth of the human proteome consists of proteins whose main function is in the brain—some estimates say it’s more like a third.
"According to Zimmer-Bensch and an increasing number of neuroscientists, the missing piece of the puzzle is RNA—specifically, the myriad RNAs that don’t code for proteins, such as long noncoding RNAs (lncRNAs) and microRNAs (miRNAs). Noncoding RNAs are likely protagonists in our brain’s evolutionary story because they are pivotal regulators of gene expression, especially during development, experts say. Changes in traits such as tissue size and shape are easily made by tweaking when and in what cells different proteins are made—precise alterations that generally occur as the result of changes in noncoding regions of the genome, researchers are finding.
"And RNAs aren’t just stars of the evolutionary and developmental past; they are essential for brain functioning now, and evidence is mounting that regulating gene expression is just one of noncoding RNAs’ many neurological tasks. For instance, some noncoding RNAs are actively transported to the ends of axons to play roles completely divorced from gene expression. Plus, notes Zimmer-Bensch, noncoding RNAs can be passed from cell to cell via vesicles and junctions. “The functional diversity [of noncoding RNAs] is tremendous and impressive.”
***
"But now, cutting-edge sequencing technologies are giving researchers unprecedented insights into cells, allowing RNA studies to be conducted on the spatial and temporal scales needed for the discipline to begin to catch up to protein biology. And findings from this work are pointing to an inevitable conclusion: RNAs rule the brain.
***
"This research has led to a shift in understanding of how the brain evolved, Silver says. “In the last 10 years, the idea that RNAs can have an impact, and that layers of regulation between a DNA and a protein are meaningful, has gotten a lot more attention.”
***
"A common hypothesis for how these RNAs function is in the control of gene expression, especially during brain development. Individual noncoding RNAs can alter the expression of multiple genes, meaning that small changes in the RNAs can have cascading effects. For example, miRNAs, short (20–26 base pairs) molecules whose most well-studied function is to bind to messenger RNAs (mRNAs) and interfere with their translation into proteins, may each have hundreds of targets—which means even single base changes could impact the expression levels of as many genes.
***
"Kosik’s work on miRNAs has found that miRNAs may sculpt brain size and shape—and therefore, cognitive complexity—via alterations to the cell cycle. “If you’re controlling the cell cycle, then in some ways you also are controlling cell divisions, and the number of neurons that are being made,” he explains. “And we know that in primates, the number of neurons increased a lot. Same is true in cephalopods.” In addition to cell number, humans are unique in the number of different neuronal cell types and other important cells in the brain, Kosik adds, and different cell types tend to have distinct miRNA profiles. “MicroRNAs are important in development and taking precursor cells along the path to various terminal differentiated outcomes . . . so they do have some correlation with cell specialization in the brain.”
***
"And specific RNAs have been proven to play pivotal roles in activities like memory formation, and especially, in creating the high degree of neuronal plasticity that is a hallmark of human brains. “The brain is rewiring itself on the fly in response to experience,” Mattick explains,"
Comment: A highly technical review article, which begins to show how our brain developed.
Human evolution; our feet differ from apes.
by David Turell , Wednesday, February 26, 2020, 20:13 (1730 days ago) @ dhw
Our foot is stiffer and exerts more force:
https://phys.org/news/2020-02-overlooked-arch-foot-key-evolution.html
"long-overlooked part of the human foot is key to how the foot works, how it evolved, and how we walk and run, a Yale-led team of researchers said.
"The discovery upends nearly a century of conventional thinking about the human foot
***
"When humans walk and run, the front of each foot repeatedly pushes on the ground with a force exceeding several times the body's weight. Despite these strong forces, the human foot maintains its shape without severely bending. Such stiff feet—unique to humans among primates—were important for the evolution of bipedalism. (my bold)
"What makes human feet so stiff? According to conventional thinking, it's mainly the longitudinal arch of the foot. This arch runs from heel to forefoot and is reinforced by elastic tissues underneath it. The arch and tissues create a bow-and-string structure that for nearly a century was considered the main source of the foot's stiffness.
"But the foot has a second arch that runs across the width of the midfoot, known as the transverse arch. Venkadesan and his colleagues investigated the transverse arch, which had not been studied previously. They performed a series of experiments,using mechanical mimics of the foot, cadaveric human feet, and fossil samples from long-extinct human ancestors and relatives (hominins). Their results show that the transverse arch is the main source of the foot's stiffness.
"The reason the transverse arch is so important can be found in your wallet. Take out a dollar bill, hold it at one end, and the dollar flops around. But press your thumb down to give the dollar some curvature, and it stands out straight.
"'That type of effect also works in the foot," said Venkadesan, assistant professor of mechanical engineering and materials science. "It's not as simple as a sheet of paper because there are many other tissues and structures in the foot, but the principle turns out to be the same."
***
"'We found that transverse springs, which mimic tissues spanning the width of your foot, are crucial for curvature-induced stiffness," said Ali Yawar, a Ph.D. student in Venkadesan's lab. "So we expected that stiffness would decrease in real human feet if we were to remove the transverse tissues and leave everything else untouched."
***
"We found that the transverse arch, acting through the transverse tissues, is responsible for nearly half of the foot's stiffness, considerably more than what the longitudinal arch contributes," said Carolyn Eng, an associate research scientist in Venkadesan's lab.
"These results may also explain how the 3.66 million-year-oldAustralopithecus afarensis, the same species as the fossil Lucy, could have walked and left a human-like footprint despite having no apparent longitudinal arch. Working with Andrew Haims, a professor at the Yale School of Medicine, the researchers developed a new technique to measure transverse curvature using partial skeletons of the foot. By applying this technique to fossil samples, includingA. afarensis, they traced how the transverse arch evolved among early hominins.
"'Our evidence suggests that a human-like transverse arch may have evolved over 3.5 million years ago, a whole 1.5 million years before the emergence of the genus Homo, and was a key step in the evolution of modern humans," Venkadesan said". (my bold)
Comment: we are as different from apes in our physical attributes as in our special brain. Note my bolds: Stiffness developed long before true Homo species arrived. I view this as God pre-planning our appearance as He managed evolution. From the Darwin standpoint, why should Lucy develop a stiff foot she didn't really need when she existed? She could run faster which tells us she was designed to be able to save herself on the ground by running. This means she was designed with the ability to protect her on the ground from the beginning of her species appearance. Not a slow Darwinian adaptation.
Human evolution; our feet differ from apes.
DAVID: Our feet differ from apes
QUOTES: "When humans walk and run, the front of each foot repeatedly pushes on the ground with a force exceeding several times the body's weight. Despite these strong forces, the human foot maintains its shape without severely bending. Such stiff feet—unique to humans among primates—were important for the evolution of bipedalism[/b]. (David’s bold)
I would certainly agree with the bold, but would also suggest that bipedalism led to the evolution of stiffer feet.
All "'Our evidence suggests that a human-like transverse arch may have evolved over 3.5 million years ago, a whole 1.5 million years before the emergence of the genus Homo, and was a key step in the evolution of modern humans," Venkadesan said". (David’s bold)
DAVID: we are as different from apes in our physical attributes as in our special brain. Note my bolds: Stiffness developed long before true Homo species arrived. I view this as God pre-planning our appearance as He managed evolution.
I have no idea why your God, who apparently can design what he wants to design in any way he wants, should find it necessary to preprogramme or dabble all these different phases, tinkering with feet, hands, pelvises, brains, in order to design the only species he wanted to design, but we can leave this to the thread on your theory of evolution. I would suggest that these developments follow a natural process whereby parts of the body may change according to usage and the demands of the environment, as organisms seek to survive or enhance their chances of survival. This is actually what you suggest in your next comment:
DAVID: From the Darwin standpoint, why should Lucy develop a stiff foot she didn't really need when she existed? She could run faster which tells us she was designed to be able to save herself on the ground by running.
And so you have answered your own question. The stiff foot developed because it improved her chances of survival. This to me sounds far more reasonable than the suggestion that God stiffened her foot in order to “pre-plan our appearance” 1.5 million years later.
DAVID: This means she was designed with the ability to protect her on the ground from the beginning of her species appearance. Not a slow Darwinian adaptation.
It’s a pity we don’t have a few thousand pre-Lucys to see how stiff all her ancestors’ feet were. And then a few thousand more fossils to see how stiff the feet were between all the generations of all the hominins and early homos prior to Sapiens. Without them, of course, it’s impossible to say how fast or slow the adaptation was.
Human evolution; our feet differ from apes.
by David Turell , Thursday, February 27, 2020, 20:02 (1729 days ago) @ dhw
DAVID: Our feet differ from apes
QUOTES: "When humans walk and run, the front of each foot repeatedly pushes on the ground with a force exceeding several times the body's weight. Despite these strong forces, the human foot maintains its shape without severely bending. Such stiff feet—unique to humans among primates—were important for the evolution of bipedalism[/b]. (David’s bold)
I would certainly agree with the bold, but would also suggest that bipedalism led to the evolution of stiffer feet.
All "'Our evidence suggests that a human-like transverse arch may have evolved over 3.5 million years ago, a whole 1.5 million years before the emergence of the genus Homo, and was a key step in the evolution of modern humans," Venkadesan said". (David’s bold)
DAVID: we are as different from apes in our physical attributes as in our special brain. Note my bolds: Stiffness developed long before true Homo species arrived. I view this as God pre-planning our appearance as He managed evolution.
dhw: I have no idea why your God, who apparently can design what he wants to design in any way he wants, should find it necessary to preprogramme or dabble all these different phases, tinkering with feet, hands, pelvises, brains, in order to design the only species he wanted to design, but we can leave this to the thread on your theory of evolution. I would suggest that these developments follow a natural process whereby parts of the body may change according to usage and the demands of the environment, as organisms seek to survive or enhance their chances of survival. This is actually what you suggest in your next comment:
DAVID: From the Darwin standpoint, why should Lucy develop a stiff foot she didn't really need when she existed? She could run faster which tells us she was designed to be able to save herself on the ground by running.
dhw: And so you have answered your own question. The stiff foot developed because it improved her chances of survival. This to me sounds far more reasonable than the suggestion that God stiffened her foot in order to “pre-plan our appearance” 1.5 million years later.
As usual you are back to Darwin and I'm sticking with God the designer who knew she had to run faster. She survived so she probably had stiffer feet when she appeared after the huge fossil gap in evolution from apes. In your theory the pre-Lucy knew she had the need to move quickly so she designed her feet in advance, or did she stumble around and jump to the trees when necessary. We know she had long arms and ape-like shoulders
DAVID: This means she was designed with the ability to protect her on the ground from the beginning of her species appearance. Not a slow Darwinian adaptation.dhw: It’s a pity we don’t have a few thousand pre-Lucys to see how stiff all her ancestors’ feet were. And then a few thousand more fossils to see how stiff the feet were between all the generations of all the hominins and early homos prior to Sapiens. Without them, of course, it’s impossible to say how fast or slow the adaptation was.
Agreed, but she survived and my God took care of the needed designs. We have to work with the only fossils we have. It still looks like H. sapiens ended with most unusual unexpected characteristics
Human evolution; our feet differ from apes.
DAVID: From the Darwin standpoint, why should Lucy develop a stiff foot she didn't really need when she existed? She could run faster which tells us she was designed to be able to save herself on the ground by running.
dhw: And so you have answered your own question. The stiff foot developed because it improved her chances of survival. This to me sounds far more reasonable than the suggestion that God stiffened her foot in order to “pre-plan our appearance” 1.5 million years later.
DAVID: As usual you are back to Darwin and I'm sticking with God the designer who knew she had to run faster. She survived so she probably had stiffer feet when she appeared after the huge fossil gap in evolution from apes. In your theory the pre-Lucy knew she had the need to move quickly so she designed her feet in advance, or did she stumble around and jump to the trees when necessary. We know she had long arms and ape-like shoulders.
You continue to misunderstand the process I am suggesting. Yes, pre-Lucy knew she had to run quickly. No, she did not design her feet in advance. Nobody knows how feet originated, and nobody knows how non-stiff feet evolved into stiff feet, but the theory I am proposing is that as pre-Lucy and her species tried to run faster, the cell communities that form the feet and legs responded by stiffening the feet. Just as pre-whale legs became flippers in response to the need to swim instead of walk. And just as – on a smaller scale – illiterates, taxi-drivers and musicians change parts of their brain by performing certain tasks. It is always a matter of the cell communities implementing ideas and restructuring themselves IN RESPONSE to new demands and new conditions, NOT IN ANTICIPATION of them. Pre-Lucy may well have jumped into the trees when necessary. In that respect, she was a transitional form and provides direct evidence for common descent.
DAVID: This means she was designed with the ability to protect her on the ground from the beginning of her species appearance. Not a slow Darwinian adaptation.
dhw: It’s a pity we don’t have a few thousand pre-Lucys to see how stiff all her ancestors’ feet were. And then a few thousand more fossils to see how stiff the feet were between all the generations of all the hominins and early homos prior to Sapiens. Without them, of course, it’s impossible to say how fast or slow the adaptation was.
DAVID: Agreed, but she survived and my God took care of the needed designs. We have to work with the only fossils we have. It still looks like H. sapiens ended with most unusual unexpected characteristics.
Unexpected by whom? There are loads of species that ended with most unusual characteristics. Why is the human foot more unusual than the elephant’s trunk or the camel’s hump? But yes, humans are remarkable animals, and yes, we can only work with the fossils we have. These suggest a stage by stage development of certain organs, supporting the case for common descent. All the changes fit in with the theory that God – if he exists – preprogrammed every single one 3.8 billion years ago, or he popped in to dabble every single one, or he designed a mechanism that enabled cells/cell communities to do their own designing. We should leave discussion of the possible variations, implications and logicality of these three theories to the thread concerning your own theory.
Human evolution; our feet differ from apes.
by David Turell , Sunday, March 01, 2020, 18:29 (1726 days ago) @ dhw
DAVID: As usual you are back to Darwin and I'm sticking with God the designer who knew she had to run faster. She survived so she probably had stiffer feet when she appeared after the huge fossil gap in evolution from apes. In your theory the pre-Lucy knew she had the need to move quickly so she designed her feet in advance, or did she stumble around and jump to the trees when necessary. We know she had long arms and ape-like shoulders.
dhw: You continue to misunderstand the process I am suggesting. Yes, pre-Lucy knew she had to run quickly. No, she did not design her feet in advance. Nobody knows how feet originated, and nobody knows how non-stiff feet evolved into stiff feet, but the theory I am proposing is that as pre-Lucy and her species tried to run faster, the cell communities that form the feet and legs responded by stiffening the feet. Just as pre-whale legs became flippers in response to the need to swim instead of walk. And just as – on a smaller scale – illiterates, taxi-drivers and musicians change parts of their brain by performing certain tasks. It is always a matter of the cell communities implementing ideas and restructuring themselves IN RESPONSE to new demands and new conditions, NOT IN ANTICIPATION of them. Pre-Lucy may well have jumped into the trees when necessary. In that respect, she was a transitional form and provides direct evidence for common descent.
I still accept common descent, but I think God ran the process and prepared for future problems, so I do not misunderstand your position. Once on the ground Lucy had to be speedy or she would not have survived the predators who were faster. She had to be designed for survival, not develop it as she was on the ground. Further your theory ignores the gaps in the fossil record with its assumption the cell committees adapt, that would imply a gradual change for which there is no record. The gaps tell us that the cell committees would have bean able to see the necessary future designs that were needed. Really!
DAVID: This means she was designed with the ability to protect her on the ground from the beginning of her species appearance. Not a slow Darwinian adaptation.dhw: It’s a pity we don’t have a few thousand pre-Lucys to see how stiff all her ancestors’ feet were. And then a few thousand more fossils to see how stiff the feet were between all the generations of all the hominins and early homos prior to Sapiens. Without them, of course, it’s impossible to say how fast or slow the adaptation was.
DAVID: Agreed, but she survived and my God took care of the needed designs. We have to work with the only fossils we have. It still looks like H. sapiens ended with most unusual unexpected characteristics.
dhw: Unexpected by whom? There are loads of species that ended with most unusual characteristics. Why is the human foot more unusual than the elephant’s trunk or the camel’s hump? But yes, humans are remarkable animals, and yes, we can only work with the fossils we have. These suggest a stage by stage development of certain organs, supporting the case for common descent. All the changes fit in with the theory that God – if he exists – preprogrammed every single one 3.8 billion years ago, or he popped in to dabble every single one, or he designed a mechanism that enabled cells/cell communities to do their own designing. We should leave discussion of the possible variations, implications and logicality of these three theories to the thread concerning your own theory.
There is no point in disconnecting different parts of the same evolutionary process we are analyzing. We humans are the endpoint and our vast difference in its result conditions my view about the control of evolution, which I assign to God. Our special feet are one simple example, and as other unrecognized difference show up I will report them, as they sustain my view.
Human evolution; our feet differ from apes.
DAVID: In your theory the pre-Lucy knew she had the need to move quickly so she designed her feet in advance, or did she stumble around and jump to the trees when necessary. We know she had long arms and ape-like shoulders.
dhw: You continue to misunderstand the process I am suggesting. Yes, pre-Lucy knew she had to run quickly. No, she did not design her feet in advance. Nobody knows how feet originated, and nobody knows how non-stiff feet evolved into stiff feet, but the theory I am proposing is that as pre-Lucy and her species tried to run faster, the cell communities that form the feet and legs responded by stiffening the feet. […] Pre-Lucy may well have jumped into the trees when necessary. In that respect, she was a transitional form and provides direct evidence for common descent.
DAVID: I still accept common descent, but I think God ran the process and prepared for future problems, so I do not misunderstand your position.
She did not “design her feet in advance”. You constantly misrepresent my theory by saying it involves foreseeing the future. It doesn’t. Organisms/cell communities respond to the needs of the present.
DAVID: Once on the ground Lucy had to be speedy or she would not have survived the predators who were faster. She had to be designed for survival, not develop it as she was on the ground.
No doubt many of her contemporaries did not survive, and she herself is believed to have been a “young adult” when she died, so she didn’t survive long either!
DAVID: Further your theory ignores the gaps in the fossil record with its assumption the cell committees adapt, that would imply a gradual change for which there is no record. The gaps tell us that the cell committees would have bean able to see the necessary future designs that were needed. Really!
How often must I emphasize that they do NOT foresee anything! The gaps tell us that once there were no transverse arches, and later there were transverse arches. My comment was:
dhw: It’s a pity we don’t have a few thousand pre-Lucys to see how stiff all her ancestors’ feet were. And then a few thousand more fossils to see how stiff the feet were between all the generations of all the hominins and early homos prior to Sapiens. Without them, of course, it’s impossible to say how fast or slow the adaptation was.
DAVID: Agreed, but she survived and my God took care of the needed designs. We have to work with the only fossils we have.
That does not mean we can assume that there was not a gradual development and that your God must have jumped in at a specific moment to pop in a transverse arch.
DAVID: It still looks like H. sapiens ended with most unusual unexpected characteristics.
dhw: Unexpected by whom? There are loads of species that ended with most unusual characteristics. Why is the human foot more unusual than the elephant’s trunk or the camel’s hump? But yes, humans are remarkable animals, and yes, we can only work with the fossils we have. These suggest a stage by stage development of certain organs, supporting the case for common descent.
See "David's Theory of Evolution" for continuation...
Human evolution; our feet differ from apes.
by David Turell , Monday, March 02, 2020, 22:24 (1725 days ago) @ dhw
DAVID: I still accept common descent, but I think God ran the process and prepared for future problems, so I do not misunderstand your position.
dhw: She did not “design her feet in advance”. You constantly misrepresent my theory by saying it involves foreseeing the future. It doesn’t. Organisms/cell communities respond to the needs of the present.
And again you skip the gaps in the fossil record. Changes are always after the gap, no itty bitty adaptive steps ever seen..
DAVID: Further your theory ignores the gaps in the fossil record with its assumption the cell committees adapt, that would imply a gradual change for which there is no record. The gaps tell us that the cell committees would have bean able to see the necessary future designs that were needed. Really!How often must I emphasize that they do NOT foresee anything! The gaps tell us that once there were no transverse arches, and later there were transverse arches. My comment was:
dhw: It’s a pity we don’t have a few thousand pre-Lucys to see how stiff all her ancestors’ feet were. And then a few thousand more fossils to see how stiff the feet were between all the generations of all the hominins and early homos prior to Sapiens. Without them, of course, it’s impossible to say how fast or slow the adaptation was.
So we are left with gaps tht strongly support design.
DAVID: Agreed, but she survived and my God took care of the needed designs. We have to work with the only fossils we have.dhw: That does not mean we can assume that there was not a gradual development and that your God must have jumped in at a specific moment to pop in a transverse arch.
Your double negative again suggests itty bitty adaptations, with no evidence.
DAVID: It still looks like H. sapiens ended with most unusual unexpected characteristics.dhw: Unexpected by whom? There are loads of species that ended with most unusual characteristics. Why is the human foot more unusual than the elephant’s trunk or the camel’s hump? But yes, humans are remarkable animals, and yes, we can only work with the fossils we have. These suggest a stage by stage development of certain organs, supporting the case for common descent.
I agree common descent run by God the designer.
Human evolution; our feet differ from apes.
DAVID: I still accept common descent, but I think God ran the process and prepared for future problems, so I do not misunderstand your position.
dhw: She did not “design her feet in advance”. You constantly misrepresent my theory by saying it involves foreseeing the future. It doesn’t. Organisms/cell communities respond to the needs of the present.
DAVID: And again you skip the gaps in the fossil record. Changes are always after the gap, no itty bitty adaptive steps ever seen.
I was responding to your constant misrepresentation of my theory as demanding knowledge of the future. It doesn’t. So now you switch back to the gaps. Of course changes are after the gap! Even if something changed overnight, there would still be a gap between before and after!The reply I gave you to this point was:
dhw: It’s a pity we don’t have a few thousand pre-Lucys to see how stiff all her ancestors’ feet were. And then a few thousand more fossils to see how stiff the feet were between all the generations of all the hominins and early homos prior to Sapiens. Without them, of course, it’s impossible to say how fast or slow the adaptation was.
DAVID: So we are left with gaps that strongly support design.
Gaps are gaps. They don’t support any theory, and a slow adaptation could still be design through the intelligence of the cell communities.
However, your original reply was:
DAVID: Agreed, but she survived and my God took care of the needed designs. We have to work with the only fossils we have.
dhw: That does not mean we can assume that there was not a gradual development and that your God must have jumped in at a specific moment to pop in a transverse arch.
DAVID: Your double negative again suggests itty bitty adaptations, with no evidence.
Nor is there any evidence of your God stepping in and giving pre-Lucy a transverse arch. If you believe in common descent, the fossil record can only provide dots along the way. We have no idea what took place between the dots, which is why you agreed that it is impossible to say how fast or slow the adaptation was.
Human evolution; our feet differ from apes.
by David Turell , Tuesday, March 03, 2020, 19:16 (1724 days ago) @ dhw
DAVID: And again you skip the gaps in the fossil record. Changes are always after the gap, no itty bitty adaptive steps ever seen.
dhw: I was responding to your constant misrepresentation of my theory as demanding knowledge of the future. It doesn’t. So now you switch back to the gaps. Of course changes are after the gap! Even if something changed overnight, there would still be a gap between before and after!The reply I gave you to this point was:
dhw: It’s a pity we don’t have a few thousand pre-Lucys to see how stiff all her ancestors’ feet were. And then a few thousand more fossils to see how stiff the feet were between all the generations of all the hominins and early homos prior to Sapiens. Without them, of course, it’s impossible to say how fast or slow the adaptation was.
DAVID: So we are left with gaps that strongly support design.
dhw: Gaps are gaps. They don’t support any theory, and a slow adaptation could still be design through the intelligence of the cell communities.
With no fossil evidence! You are not as troubled as Gould was. He had to invent punc-inc to satisfy himself about gaps.
However, your original reply was:
DAVID: Agreed, but she survived and my God took care of the needed designs. We have to work with the only fossils we have.dhw: That does not mean we can assume that there was not a gradual development and that your God must have jumped in at a specific moment to pop in a transverse arch.
DAVID: Your double negative again suggests itty bitty adaptations, with no evidence.
dhw: Nor is there any evidence of your God stepping in and giving pre-Lucy a transverse arch. If you believe in common descent, the fossil record can only provide dots along the way. We have no idea what took place between the dots, which is why you agreed that it is impossible to say how fast or slow the adaptation was.
Gaps make it seem as if changes are fast. You are not explaining them, although as time passes they never go away.
Human evolution; our feet differ from apes.
DAVID: And again you skip the gaps in the fossil record. Changes are always after the gap, no itty bitty adaptive steps ever seen.
dhw: I was responding to your constant misrepresentation of my theory as demanding knowledge of the future. It doesn’t. So now you switch back to the gaps. Of course changes are after the gap! Even if something changed overnight, there would still be a gap between before and after! The reply I gave you to this point was:
dhw: It’s a pity we don’t have a few thousand pre-Lucys to see how stiff all her ancestors’ feet were. And then a few thousand more fossils to see how stiff the feet were between all the generations of all the hominins and early homos prior to Sapiens. Without them, of course, it’s impossible to say how fast or slow the adaptation was.
Your original reply to this was: “Agreed, but she survived and my God took care of the needed designs. We have to work with the only fossils we have.”
You agree that without fossils it’s impossible to say how fast or slow the adaptation was.
DAVID: So we are left with gaps that strongly support design.
dhw: Gaps are gaps. They don’t support any theory, and a slow adaptation could still be design through the intelligence of the cell communities.
DAVID: With no fossil evidence! You are not as troubled as Gould was. He had to invent punc-inc to satisfy himself about gaps.
We cannot expect an inch by inch fossil record leading from one species to another. Every single find is hailed as momentous precisely because it is almost miraculous for bones to survive for thousands and millions of years. You claim that the gaps mean God stepped in and did a dabble (and presumably did more and more dabbles as, with his unlimited powers, he apparently continued to assemble and then discard all the different hominins and homos on his way to designing the only one he really wanted, which was us). Your alternative is a 3.8-billion-year-old computer programme for stiff transverse arches, which suddenly switched itself on. I’m afraid I don’t find this theory even remotely as believable as that of the absence of fossils, plus the fact that in accordance with the theory that changing environmental conditions are the trigger for adaptation and innovation, the long periods of stasis between environmental upheavals inevitably create “gaps” (hence Gould’s punc-inc, which I regard as perfectly logical).
Human evolution; our feet differ from apes.
by David Turell , Wednesday, March 04, 2020, 20:55 (1723 days ago) @ dhw
DAVID: And again you skip the gaps in the fossil record. Changes are always after the gap, no itty bitty adaptive steps ever seen.
dhw: I was responding to your constant misrepresentation of my theory as demanding knowledge of the future. It doesn’t. So now you switch back to the gaps. Of course changes are after the gap! Even if something changed overnight, there would still be a gap between before and after! The reply I gave you to this point was:
dhw: It’s a pity we don’t have a few thousand pre-Lucys to see how stiff all her ancestors’ feet were. And then a few thousand more fossils to see how stiff the feet were between all the generations of all the hominins and early homos prior to Sapiens. Without them, of course, it’s impossible to say how fast or slow the adaptation was.dhw: Your original reply to this was: “Agreed, but she survived and my God took care of the needed designs. We have to work with the only fossils we have.”
dhw: You agree that without fossils it’s impossible to say how fast or slow the adaptation was.
DAVID: So we are left with gaps that strongly support design.
dhw: Gaps are gaps. They don’t support any theory, and a slow adaptation could still be design through the intelligence of the cell communities.
DAVID: With no fossil evidence! You are not as troubled as Gould was. He had to invent punc-inc to satisfy himself about gaps.
dhw: We cannot expect an inch by inch fossil record leading from one species to another. Every single find is hailed as momentous precisely because it is almost miraculous for bones to survive for thousands and millions of years. You claim that the gaps mean God stepped in and did a dabble (and presumably did more and more dabbles as, with his unlimited powers, he apparently continued to assemble and then discard all the different hominins and homos on his way to designing the only one he really wanted, which was us). Your alternative is a 3.8-billion-year-old computer programme for stiff transverse arches, which suddenly switched itself on. I’m afraid I don’t find this theory even remotely as believable as that of the absence of fossils, plus the fact that in accordance with the theory that changing environmental conditions are the trigger for adaptation and innovation, the long periods of stasis between environmental upheavals inevitably create “gaps” (hence Gould’s punc-inc, which I regard as perfectly logical).
All we can see about the gaps is larger brains and more complexity of artifacts appear simultaneously. The complexity of the artifacts strongly implies the new brain is more complex and made the new artifacts. For some weird line of thinking you want the old brain to create the new artifacts and suddenly jump in size and appear simultaneously with them.
Human evolution; our feet differ from apes.
dhw: We cannot expect an inch by inch fossil record leading from one species to another. Every single find is hailed as momentous precisely because it is almost miraculous for bones to survive for thousands and millions of years. You claim that the gaps mean God stepped in and did a dabble (and presumably did more and more dabbles as, with his unlimited powers, he apparently continued to assemble and then discard all the different hominins and homos on his way to designing the only one he really wanted, which was us). Your alternative is a 3.8-billion-year-old computer programme for stiff transverse arches, which suddenly switched itself on. I’m afraid I don’t find this theory even remotely as believable as that of the absence of fossils, plus the fact that in accordance with the theory that changing environmental conditions are the trigger for adaptation and innovation, the long periods of stasis between environmental upheavals inevitably create “gaps” (hence Gould’s punc-inc, which I regard as perfectly logical).
DAVID: All we can see about the gaps is larger brains and more complexity of artifacts appear simultaneously. The complexity of the artifacts strongly implies the new brain is more complex and made the new artifacts. For some weird line of thinking you want the old brain to create the new artifacts and suddenly jump in size and appear simultaneously with them.
We were talking about transverse arches, and for some reason you have switched back to brains – dealt with under “half a brain”. My paragraph above dealt with the gaps, and compared your theory to my own and to Gould’s. I’m afraid I would regard your theory, bolded above, as rather more weird than my own – but of course that is a merely an opinion which is just as subjective as your own.
Human evolution; our feet differ from apes.
by David Turell , Thursday, March 05, 2020, 15:39 (1722 days ago) @ dhw
dhw: We cannot expect an inch by inch fossil record leading from one species to another. Every single find is hailed as momentous precisely because it is almost miraculous for bones to survive for thousands and millions of years. You claim that the gaps mean God stepped in and did a dabble (and presumably did more and more dabbles as, with his unlimited powers, he apparently continued to assemble and then discard all the different hominins and homos on his way to designing the only one he really wanted, which was us). Your alternative is a 3.8-billion-year-old computer programme for stiff transverse arches, which suddenly switched itself on. I’m afraid I don’t find this theory even remotely as believable as that of the absence of fossils, plus the fact that in accordance with the theory that changing environmental conditions are the trigger for adaptation and innovation, the long periods of stasis between environmental upheavals inevitably create “gaps” (hence Gould’s punc-inc, which I regard as perfectly logical).
DAVID: All we can see about the gaps is larger brains and more complexity of artifacts appear simultaneously. The complexity of the artifacts strongly implies the new brain is more complex and made the new artifacts. For some weird line of thinking you want the old brain to create the new artifacts and suddenly jump in size and appear simultaneously with them.
dhw: We were talking about transverse arches, and for some reason you have switched back to brains – dealt with under “half a brain”. My paragraph above dealt with the gaps, and compared your theory to my own and to Gould’s. I’m afraid I would regard your theory, bolded above, as rather more weird than my own – but of course that is a merely an opinion which is just as subjective as your own.
My view is God designed the transverse arch, nothing more. You brought up 'gaps' and that always gets me back to brain size and reasons.
Human evolution; bipedalism and savannahs
by David Turell , Wednesday, September 11, 2024, 22:07 (71 days ago) @ David Turell
Savannahs did not force bipedalism:
https://www.newscientist.com/article/2447242-when-did-humans-leave-the-trees-for-the-sa...
"The carbon isotopes in the guano were characteristic of forest plants, not of grasses, implying that the environment was a tropical rainforest. In line with this, the team found pollen from trees like she-oak and mangroves.
"The researchers also looked at the stone tools found in Tabon cave. Of 41 studied in detail, 23 had signs of being used to cut and prepare plants. Some of them seem to have been used for cutting hard plants like bamboo – for instance, splitting long stems along their length. The people may have been making objects like baskets, ropes and fasteners.
"The stone tools Xhauflair’s team studied were found in layers dating from between 39,000 and 30,000 years ago. This is long before agriculture, so the people using them were hunter-gatherers. Clearly, they succeeded in living in a tropical rainforest for thousands of years.
"This doesn’t match the “rainforests bad for humans” scenario. In fact, it fits an emerging body of evidence that humans and our hominin relatives often lived in dense forests.
"Let’s first consider the recent past, by which I mean the past 10,000 years or so – the period in which agriculture became more widespread.
Some of the strongest evidence for people living in tropical forests in this period comes from the Amazon...this vast rainforest was filled with sprawling settlements and the inhabitants cultivated dozens of plants and animals. Just last year, researchers estimated that there are more than 10,000 undiscovered archaeological sites in the Amazon. These “ghost cities” suggest that complex societies didn’t all develop in the same way: the Amazon inhabitants lived in built-up areas (made from mud, not stone), but they didn’t chop down the forest or fully convert to a farming lifestyle.
"Put simply, these people didn’t leave the trees behind.
***
"One key site is Panga ya Saidi, a cave in Kenya that contains evidence of humans 78,000 years ago living in a region with a mixture of tropical forests and grasslands. There are suggestions that the inhabitants made nets and other such perishable tools to hunt small animals.
"...The “hobbits” (Homo floresiensis) lived on the island of Flores, now part of Indonesia, for hundreds of thousands of years until about 50,000 years ago. Flores was densely forested, so clearly they had adapted to that environment. The similarly small Homo luzonensis from Luzon in the Philippines (not too far from Tabon cave) also inhabited a thick forest; a 2023 study concluded they did so at least 134,000 years ago.
***
" The classic notion, which emerged gradually in the 20th century, is called the savannah hypothesis. It’s quite simple: some of the apes left the forests and moved out onto the savannahs, and this created an evolutionary pressure to walk upright rather than the knuckle-walking apes do.
"This idea has come in for a lot of criticism in recent decades. In a 2015 journal paper, Brigitte Senut wrote: “The famous ‘savannah hypothesis’ is no longer tenable.” Senut had discovered a 6-million-year-old hominin called Orrorin, which appears to have been bipedal, despite being such an early hominin and despite apparently living in a wooded environment. More recent species like Ardipithecus ramidus, from 4.4 million years ago, also walked upright and lived among trees.
***
"Domínguez-Rodrigo’s argument is that there are actually two versions of the savannah hypothesis: one envisions the savannahs as grasslands, the other sees them more as mosaic environments with a mix of grassland and woodland. He says the pure-grassland hypothesis “is no longer tenable”, but that there is “compelling support” for the mixed-habitat hypothesis.
"Further support came in 2020, with a study that tried to reconstruct how African habitats have changed over time by estimating the evolutionary ages of various savannah tree species. Between 15 and 10 million years ago, the team concluded, savannahs expanded in the tropics and subtropics, before eventually reaching southern Africa around 3 million years ago.
"I am in two minds about this study. On the one hand, it does indicate that savannahs expanded while dense forests shrank – which would have pushed apes and hominins out onto the grasslands. On the other hand, the timings don’t really match. Remember, we don’t see decent evidence of bipedality until 6 million years ago: why so late, if the savannahs began expanding 9 million years earlier? Likewise, we don’t see hominins living in truly open grassland until as recently as 2 million years ago.
"The answer may be that our ancestors started walking upright in trees, not on the ground. This idea is controversial but has been gathering momentum for 20 years.
***
"Hence my suspicion that the core idea of human evolution in the 20th century is, if not entirely wrong, seriously incomplete. The story isn’t how and when we left the trees. While we do spend less time in them than other apes, they are still key to our habitats and wellbeing. In a sense, we never really left."
Comment: the savannah theory skips the point that things happen slowly over time. There is no sudden appearance of vast grasslands forcing an immediate upright posture.
Human evolution; recent new modifications
by David Turell , Friday, September 13, 2024, 17:47 (69 days ago) @ David Turell
Studies of the median artery:
https://www.sciencealert.com/humans-keep-growing-an-extra-artery-in-their-arms-and-here...
"An artery that temporarily runs down the center of our forearms while we're still in the womb isn't vanishing as often as it used to, according to a study published in 2020 from researchers at Flinders University and the University of Adelaide in Australia.
"That means there are more adults than ever with what amounts to be an extra channel of vascular tissue flowing under their wrist.
"'Since the 18th century, anatomists have been studying the prevalence of this artery in adults and our study shows it's clearly increasing," Flinders University anatomist Teghan Lucas explained in 2020.
"'The prevalence was around 10 percent in people born in the mid-1880s compared to 30 percent in those born in the late 20th century, so that's a significant increase in a fairly short period of time, when it comes to evolution." (my bold)
"The median artery forms fairly early in development in all humans, transporting blood down the center of our arms to feed our growing hands.
***
"To compare the prevalence of this persistent blood channel, Lucas and colleagues Maciej Henneberg and Jaliya Kumaratilake from the University of Adelaide examined 80 limbs from cadavers, all donated by Australians of European descent.
"The donors ranged from 51 to 101 on passing, which means they were nearly all born in the first half of the 20th century.
"Noting down how often they found a chunky median artery capable of carrying a good supply of blood, the research team compared the figures with records dug out of a literature search, taking into account tallies that could over-represent the vessel's appearance.
"The fact the artery seems to be three times as common in adults today as it was more than a century ago is a startling find that suggests natural selection is favoring those who hold onto this extra bit of bloody supply.
"This increase could have resulted from mutations of genes involved in median artery development or health problems in mothers during pregnancy, or both actually," said Lucas. (my bold)
***
"'If this trend continues, a majority of people will have median artery of the forearm by 2100," said Lucas.
"This rapid rise of the median artery in adults isn't unlike the reappearance of a knee bone called the fabella, which is also three times more common today than it was a century ago.
"As small as these differences are, tiny microevolutionary changes add up to large-scale variations that come to define a species."
Comment: activities that require arm and hand use burn more calories than equivalent leg exercises burn. This would require higher blood flow. There are more hand activities now than in the past and thus the drive for more blood flow supplied. Noting my bold above, Lucas suggested gene mutations, and I wonder how many mutations are needed for this to happen in the 200 years span of this study. This is support for Shapiro's theory that DNA can be edited. An evolutionary example of adaptation, but not evidence of speciation, which is still a totally unknown process.
Human evolution; our unique speech mechanism
by David Turell , Monday, September 30, 2019, 22:53 (1879 days ago) @ David Turell
How our brain lets us hear and understand words immediately as we listen:
https://medicalxpress.com/news/2019-09-mechanisms-real-time-speech-human-brain.html
"Scientists have come a step closer to understanding how we're able to understand spoken language so rapidly, and it involves a huge and complex set of computations in the brain.
"In a study published today in the journal PNAS, researchers at the University of Cambridge developed novel computational models of the meanings of words, and tested these directly against real-time brain activity in volunteers.
"'Our ability to put words into context, depending on the other words around them, is an immediate process and it's thanks to the best computer we've ever known: the brain in our head. It's something we haven't yet managed to fully replicate in computers because it is still so poorly understood," said Lorraine Tyler, Director of the Centre for Speech, Language and the Brain at the University of Cambridge, which ran the study.
"Central to understanding speech are the processes involved in what is known as 'semantic composition' - in which the brain combines the meaning of words in a sentence as they are heard, so that they make sense in the context of what has already been said. This new study has revealed the detailed real-time processes going on inside the brain that make this possible.
"By saying the phrase: "the elderly man ate the apple" and watching how the volunteers' brains responded, the researchers could track the dynamic patterns of information flow between critical language regions in the brain.
"As the word 'eat' is heard, it primes the brain to put constraints on how it interprets the next word in the sentence: 'eat' is likely to be something to do with food. The study shows how these constraints directly affect how the meaning of the next word in the sentence is understood, revealing the neural mechanisms underpinning this essential property of spoken language—our ability to combine sequences of words into meaningful expressions, millisecond by millisecond as the speech is heard.
"'The way our brain enables us to understand what someone is saying, as they're saying it, is remarkable," said Professor Tyler. "By looking at the real-time flow of information in the brain we've shown how word meanings are being rapidly interpreted and put into context.'" (my bold)
Comment: our amazing brain melds all the words meanings into an understandable context, as we hear the words. If complex language with a set grammar appeared only 50,000 years ago or slightly more according to current theory, when did the brain develop this ability to string meanings together? My thought is that we were given such a complex brain, as words and their meanings developed brain plasticity developed the proper listening mechanism, basically learn by use.
Human evolution; DNA from ancient hominins
by David Turell , Saturday, October 19, 2019, 19:59 (1860 days ago) @ David Turell
edited by David Turell, Saturday, October 19, 2019, 20:05
New discoveries of DNA from Neanderthals and Denisovans in Malanesians:
https://www.newscientist.com/article/2220381-long-strand-of-dna-from-neanderthals-found...
"Many people have DNA inside them that they inherited from extinct hominins like the Neanderthals – and now we know that in some cases it isn’t just tiny snippets but long stretches.
"Over the past decade, genetic analysis of human DNA has revealed that ancient humans must have interbred many times with other hominins such as Neanderthals. The result is that DNA from these extinct groups can be found in many human populations today.
"In particular, everyone whose primary ancestry was outside Africa carries some Neanderthal DNA, while many people from Asia – especially South-East Asia – have DNA from the mysterious Denisovans. Some of this DNA may have been advantageous for modern humans. (my bold)
***
"The researchers looked at the DNA of people from Melanesia, as the levels of Neanderthal and Denisovan DNA are highest in these populations. They found evidence of much longer chunks of archaic DNA in this population.
"Two large pieces of DNA were found that originate from ancient hominins. One is on chromosome 16 and comes from Denisovans. It contains two duplicated sections. The other is on chromosome 8 and comes from Neanderthals. It includes both a deletion and a duplication.
Duplications are significant because they allow the original gene to be kept, if it is useful, while the copy is free to change and potentially develop a new function. “A duplication is a type of mutation that lets you have your cake and eat it too,” says Eichler.
"Both chunks of DNA show signs of having been selected for by evolution. They seem to have been advantageous and thus become more common in the Melanesian population over the centuries. (my bold)
“'The archaics have contributed to the success of humans that left Africa,” says Eichler. Neanderthals and Denisovans lived in Europe and Asia for hundreds of thousands of years before modern humans emerged from Africa, so they would have evolved adaptations to the different climates, foods and diseases. These useful genes “were kind of test-run in our precursors”, says Eichler. “They’re basically borrowed.”
"However, it is unclear what the advantages have been. “I think the biggest challenge is proving the function,” says Eichler. This will be difficult because the genes are only found in humans, so animal studies will not help, and they have been duplicated and then subtly altered. “You’re talking about a set of genes which are a geneticist’s worst nightmare.'”
Comment: This is another answer to dhw who wonders why God took so long to make H. sapiens. As I've noted before our ancestors developed traits that were passed on as helpful genetics developed in different climates and conditions. My bolds and the last quotes make the exact point. From another article further information:
https://phys.org/news/2019-10-neanderthal-denisovan-dna-early-melanesian.html
"The researchers report that they found instances of inherited CNVs from Denisovans and Neanderthals in modern Melanesian DNA that could be associated with adaptive selection. The researchers suggest the added DNA must have provided some benefit for it to remain in the Melanesian genome for so long. The adaption selections were identified as being associated with immunity, diet, cellular function and metabolism. Their findings suggest that early Melanesian people might have benefited from interbreeding with their early cousins in ways that might have helped them survive in their unique island environments.
"The researchers note that much more work is required to better understand why the inherited CNVs have remained present in the DNA up to the present. The idea that they might have persisted because they were useful has precedent, the researchers note—prior research has shown that Denisovan DNA helped Tibetan people survive in their high-elevation homeland by giving them a means of staving off hypoxia. "
Human evolution; sapiens and Neanderthals controlled fire
by David Turell , Sunday, October 27, 2019, 16:05 (1852 days ago) @ David Turell
Both types learned to control fire:
https://www.sciencedaily.com/releases/2019/10/191025101345.htm
"Now, a team of University of Connecticut researchers, working with colleagues from Armenia, the U.K., and Spain, has found compelling evidence that early humans such as Neanderthals not only controlled fire, but also mastered the ability to generate it.
"'Fire was presumed to be the domain of Homo sapiens but now we know that other ancient humans like Neanderthals could create it," says co-author Daniel Adler, associate professor in anthropology. "So perhaps we are not so special after all."
***
"Using specific fire-related molecules deposited in the archaeological record and an analysis of climatological clues, the researchers examined Lusakert Cave 1 in the Armenian Highlands.
"'Fire starting is a skill that has to be learned -- I never saw anyone who managed to produce fire without first being taught. So the assumption that someone has the capability to set fire at will is a source of debate," says Gideon Hartman, associate professor of anthropology, and study co-author.
***
"'In order to routinely access naturally caused fires, there would need to have been conditions that would produce lighting strikes at a relative frequency that could have ignited wildfires," says Hren.
"By pairing the climate data with the evidence found in the archaeological record, the researchers then determined the cave's inhabitants were not living in drier, wildfire-prone conditions while they were utilizing fires within the cave.
"In fact, there were fewer wildfires for these ancient humans to harvest at the time when fire frequency and heavy PAH frequency was high in the cave, says Brittingham.
"'It seems they were able to control fire outside of the natural availability of wildfires," says Brittingham."
Comment: another nail in the coffin of the dumb-type Neanderthal.
Human evolution; new fossil foretells the human future
by David Turell , Thursday, November 07, 2019, 01:00 (1841 days ago) @ David Turell
A newly described European fossil is part ape, part humanoid and is over eleven million year old. It has some non-ape upright posture, with more ape-like arms:
https://www.smithsonianmag.com/science-nature/new-ancient-ape-species-rewrites-story-bi...
"Danuvius guggenmosi, a “totally new and different” species of ape, would have moved through the trees using its forelimbs and hindlimbs equally.
***
"Böhme and colleagues determined that the bones they found came from a dryopithecine ape, an extinct ancestor of humans and great apes that once lived in the Miocene epoch. The fossils are approximately 11.6 million years old and came from at least four individual apes, including one partial skeleton. The team described the newfound ancestor, named Danuvius guggenmosi,
"D. guggenmosi was likely a small primate about the size of baboon, with long arms like a bonobo. The creature had flexible elbows and strong hands capable of grasping, which suggests that it could have swung from tree to tree like a modern great ape. But the similarities with known apes stop there. The animal’s lower limbs have much more in common with human anatomy.
" With extended hips and knees, D. guggenmosi was capable of standing with a straighter posture than that of living African apes, and its knees and ankles were adapted to bear weight. The animal’s locomotion would have therefore shared similarities with both human and ape movement, and D. guggenmosi may have been able to navigate the forest by swinging from tree limbs and walking on two legs.
“'There is no reason to think it would not have used all four limbs when that made sense, for example, on smaller branches where balance was an issue,” Begun says. “But it was also capable of both chimp-like suspension and unassisted bipedalism.”
"D. guggenmosi puts bipedality on the evolutionary timeline far earlier than scientists previously expected. Jeremy DeSilva, a paleoanthropologist who reviewed the study for Nature, says while this discovery sheds some light on how hominids began to walk on two feet, it also raises new questions about the evolution of locomotion. Rather than humans evolving to become bipedal after splitting from a quadruped ancestor, the great apes must have evolved from a creature with bipedal capabilities. (my bold)
“'Given what we know about the relationships between humans and the African great apes, then gorillas and chimpanzees would have had to have independently evolved knuckle-walking. That would have happened twice,” DeSilva says. “That is unsettling. It's disruptive to what we once thought.”
Böhme says it is also worth noting that D. guggenmosi was found in Europe, far from where most people imagine ancient apes lived. The narrative of human evolution is typically set on the African stage, but before early humans evolved, some of their primate relatives were living in forests that stretched across the Mediterranean. “We have to keep in mind that a big part of human history or human early evolution was not an African story,” Böhme says. ( my bold)
More commentary:
https://cosmosmagazine.com/palaeontology/fossils-provide-new-insights-into-when-apes-be...
"How humans came to walk on two legs is central to these debates, she adds, and several ideas have been put forward over the past 150 years.
"These include notions that bipedal humans evolved from tree-dwelling, monkey-like apes that moved on all fours, from tree-swinging apes similar to orangutans, or from knuckle-walking apes like chimpanzees and gorillas.
"Fossil evidence to support these theoretical models has so far been weak, and the new fossils from the mid to late Miocene, discovered in the Allgäu region of Bavaria in Germany, suggest that none is correct. (my bold)
"The researchers excavated more than 15,000 fossil vertebrate bones from the ancient humid, forested ecosystems that characterised Germany at that time. These included the remains of at least four individual hominids: one male, two females and one juvenile.
***
“'Importantly, for the first time, we were able to investigate several functionally important joints, including the elbow, wrist, hip, knee and ankle, in a single fossil of this age,” Böhme says.
“'And it was astonishing for us to realise how similar certain bones are to humans, as opposed to great apes.” (my bold)
***
“'Given that all living apes use bipedalism to some degree – often in the trees, but also on the ground – it is not unreasonable to suggest that bipedalism evolved much earlier in hominoid evolution than we previously thought."
Comment: Tell me this is not an advance change well before bipedalism was really needed. Gone is the theory that savanna appearance forced the change.
Human evolution; a new hominin found this year
by David Turell , Friday, December 13, 2019, 23:48 (1804 days ago) @ David Turell
Introducing Homo luzonensis:
https://www.smithsonianmag.com/smithsonian-institution/heres-what-2019-scientific-disco...
"Enter Homo luzonensis. In April a team led by Florent Détroit from the Musée de l’Homme in Paris, France, announced the discovery of fossil remains of at least two adults and one child of a new hominin species. They were found in Callao Cave on the island of Luzon in the Philippines and date to between 50,000 and 67,000 years old. This discovery was exciting not just because it’s a new species, but because of how it changes our earlier understanding of the first hominin migrations out of Africa and into Asia.
"Homo luzonensis was around at the same time as Neanderthals, Denisovans, Homo floresiensis and our own species, Homo sapiens, but it displays a unique mosaic of physical characteristics unlike any of these other hominins. Some of its features look very ancient. For instance, the small size and simplified crowns of its molars and the 3-D shape and curvature of its finger and toe bones look most similar to australopiths, but other features of its teeth are more similar to Paranthropus, Homo erectus and even Homo sapiens.
"Since its hands and feet have features that are even more ancient than those of Homo erectus, does this mean that its ancestor is an even earlier hominin that migrated out of Africa? Only the discovery of more fossils will answer that question. Similarly, in 2004 the question of whether an even more ancient species than Homo erectus migrated out of Africa was raised after the discovery of Homo floresiensis. As this new species also has some anatomical features similar to early species of Homo, the question seems even less settled now with the discovery of another late-surviving island-dwelling species outside of Africa."
Comment: It looks like we will find more and more branches in the bush of hominins. To me there is an obvious push to get us evolved. The bald facts are all the other advanced apes did not move on like we did in this burst of activity.
Human evolution; a new hominin find this year
by David Turell , Friday, December 13, 2019, 23:54 (1804 days ago) @ David Turell
A growth in the understanding of the Australopithecus family:
https://www.smithsonianmag.com/smithsonian-institution/heres-what-2019-scientific-disco...
"One really exciting fossil find from this year was not a new species, but a new body part of a previously known species: Australopithecus anamensis. First named in 1995, this species was known only from teeth, jaws and some postcranial bones from the sites of Allia Bay and Kanapoi in northern Kenya that dated to between about 4.2 and 3.9 million years ago. But in September, a team led by the Cleveland Museum of Natural History’s Yohannes Hailie-Selassie made a stunning announcement. They had found a nearly complete 3.8 million year old Australopithecus anamensis skull at the site of Woronso-Mille in Ethiopia. This extremely well-preserved skull meant that researchers could finally characterize the face of the earliest known species of Australopithecus. Furthermore, the age of the MRD cranium indicates that A. anamensis overlapped in time with A. afarensis, the species that the well-known fossil partial skeleton “Lucy” belongs to. Why is that important? Until this year, most researchers had thought that A. anamensis gradually evolved into A. afarensis, with no overlap in time. While Hailie-Selassie’s research team say this could still be the case, they think instead it’s more likely to have occurred through a speciation event, in which a small group of genetically isolated A. anamensis, rather than the entire species A. anamensis, evolved into A. afarensis, which then lived side by side for at least 100,000 years."
Comment: So many hominins their existences overlap. I wish we knew ow the 'speciation event' occurred.
Human evolution; more about Denisovans
by David Turell , Saturday, December 14, 2019, 00:01 (1804 days ago) @ David Turell
Denisovans seemed to have been all over the place:
https://www.smithsonianmag.com/smithsonian-institution/heres-what-2019-scientific-disco...
"Scientists have since determined that Denisovans interbred with both modern humans and Neanderthals. In April, a new study of 161 modern human genomes from 14 island groups in Island Southeast Asia and New Guinea region led by Murray Cox of Massey University in New Zealand was published. The results indicate that modern humans interbred with at least three Denisovan groups that were geographically isolated from each other in deep time.
"One of these Denisovan lineages is found in East Asians, whose DNA indicates a close relationship to the fossil remains found in Denisova Cave. The other two Denisovan lineages diverged from each other around 363,000 years ago and split off from the first lineage about 283,000 years ago. Traces of one of these two lineages is mainly found in modern Papuans, while the other is found in people over a much larger area of Asia and Oceania. The implication? Denisovans are actually three different groups, with more genetic diversity in less than a dozen bones that currently comprise their entire fossil sample than in the more than 7.7 billion modern humans alive today."
Comment: All we still have is fragments of some bones like fingers but no large enough finds to get some idea of how they have have looked, but they sure were active.
Human evolution; neonatal human and Neanderthal brains
by David Turell , Saturday, December 14, 2019, 05:08 (1804 days ago) @ David Turell
The development is different:
https://www.sciencedirect.com/science/article/pii/S0960982210012820?dgcid=raven_sd_reco...
"Summary:
Neanderthals had brain sizes comparable to modern humans, but their brain cases were elongated and not globular as in Homo sapiens. It has, therefore, been suggested that modern humans and Neanderthals reached large brain sizes along different evolutionary pathways. Here, we assess when during development these adult differences emerge. This is critical for understanding whether differences in the pattern of brain development might underlie potential cognitive differences between these two closely related groups. Previous comparisons of Neanderthal and modern human cranial development have shown that many morphological characteristics separating these two groups are already established at the time of birth, and that the subsequent developmental patterns of the face are similar, though not identical. Here, we show that a globularization phase seen in the neurocranial development of modern humans after birth is absent from Neanderthals.
***
"After the constraints on neonatal shape and size imposed by the shape of the birth canal of the female pelvis are relaxed, the two species develop along different pathways.
"The difference between the developmental patterns of modern humans and Neanderthals is most prominent directly after birth, when the shape of the vault is extremely sensitive to the tempo and mode of brain growth. When the cranial bones are thin and not yet fully ossified, the shape changes of the frontal and parietal bone are largely driven by the increase in brain volume. While the growth of the face affects the shape of the cranial base it is unlikely that this alone could explain the shape changes of the parietal and occipital bone shown in Figure 1. We suggest, therefore, that species differences in brain growth rates and timing underlie the uniquely modern human globularization phase.
"We suggest, therefore, that species differences in brain growth rates and timing underlie the uniquely modern human globularization phase.
"The development of cognitive abilities during individual growth is linked to the maturation of the underlying neural circuitry: in humans, major internal brain reorganization has been documented until adolescence, and even subtle alterations of pre- and perinatal brain development have been linked to changes of the neural wiring pattern that affect behavior and cognition. The uniquely modern human pattern of early brain development is particularly interesting in the light of the recent breakthroughs in the Neanderthal genome project, which identified genes relevant to cognition that are derived in living humans. We speculate that a shift away from the ancestral pattern of brain development occurring in early Homo sapiens underlies brain reorganization and that the associated cognitive differences made this growth pattern a target for positive selection in modern humans."
Comment: Essentially our brains develop quite differently and may represent better cognition in humans. All of this evidence supports the idea we were the final goal of evolution.
Human evolution; neonatal human and Neanderthal brains
Taken from the whale thread:
DAVID: Another partial step as whales adapted more fully to living in water, which required an enormous number of physical and physiological changes.
dhw: So would you say these enormous physical changes were the result of whales adapting itty-bitty more fully to living in water, or do you think your God preprogrammed each individual change 3.8 billion years ago or kept popping in to do a new dabble in his effort to cover the time until he turned to the itty-bitty evolution of H. sapiens?
DAVID: What I believe is God guided evolution constantly or with much pre-programming or pre-planning.
The only way your God could “guide evolution constantly” is through preprogramming or dabbling. So do you think he preprogrammed or dabbled every single “enormous” whale change in order to cover the time he had decided to take before embarking on achieving his one and only purpose – the design of H. sapiens? And would you agree that since these enormous changes were “adaptations”, it is difficult to draw a borderline between adaptation and innovation as processes that lead to speciation?
Taken from all the different hominin threads:
DAVID: It looks like we will find more and more branches in the bush of hominins. To me there is an obvious push to get us evolved. The bald facts are all the other advanced apes did not move on like we did in this burst of activity.
DAVID: So many hominins their existences overlap. I wish we knew how the 'speciation event' occurred.
QUOTE: “Denisovans are actually three different groups, with more genetic diversity in less than a dozen bones that currently comprise their entire fossil sample than in the more than 7.7 billion modern humans alive today."
DAVID (on Neanderthals): Essentially our brains develop quite differently and may represent better cognition in humans. All of this evidence supports the idea we were the final goal of evolution.
As with whales, so with hominins and humans. If your God is always in charge and knows precisely what he is doing and has the one goal of producing H. sapiens, why would he have preprogrammed or dabbled so many different types of hominins and humans? At the very best, I would suggest this fits in more with divine experimentation than with a God who knows exactly how to achieve his one and only goal. So please explain your theory of why he needed to preprogramme/dabble all the different stages of whale in order to cover the time he had decided not to achieve his “final goal”, and why he needed to preprogramme or dabble all the different and now extinct forms of human if all he wanted was us and he was always in charge.
.
Human evolution; neonatal human and Neanderthal brains
by David Turell , Saturday, December 14, 2019, 15:46 (1804 days ago) @ dhw
DAVID: What I believe is God guided evolution constantly or with much pre-programming or pre-planning.
dhw: The only way your God could “guide evolution constantly” is through preprogramming or dabbling. So do you think he preprogrammed or dabbled every single “enormous” whale change in order to cover the time he had decided to take before embarking on achieving his one and only purpose – the design of H. sapiens? And would you agree that since these enormous changes were “adaptations”, it is difficult to draw a borderline between adaptation and innovation as processes that lead to speciation?
You are confusing two words: as I use them adaptation is the same species sightly adjusted. Innovation creates a new species.
Taken from all the different hominin threads:
DAVID: It looks like we will find more and more branches in the bush of hominins. To me there is an obvious push to get us evolved. The bald facts are all the other advanced apes did not move on like we did in this burst of activity.DAVID: So many hominins their existences overlap. I wish we knew how the 'speciation event' occurred.
QUOTE: “Denisovans are actually three different groups, with more genetic diversity in less than a dozen bones that currently comprise their entire fossil sample than in the more than 7.7 billion modern humans alive today."
DAVID (on Neanderthals): Essentially our brains develop quite differently and may represent better cognition in humans. All of this evidence supports the idea we were the final goal of evolution.
dhw: As with whales, so with hominins and humans. If your God is always in charge and knows precisely what he is doing and has the one goal of producing H. sapiens, why would he have preprogrammed or dabbled so many different types of hominins and humans? At the very best, I would suggest this fits in more with divine experimentation than with a God who knows exactly how to achieve his one and only goal. So please explain your theory of why he needed to preprogramme/dabble all the different stages of whale in order to cover the time he had decided not to achieve his “final goal”, and why he needed to preprogramme or dabble all the different and now extinct forms of human if all he wanted was us and he was always in charge.
Covered all of this before. The different final forms lived in different environments and with interbreeding brought different beneficial attributes to the human final product. It is quite clear to me God knew how to evolve humans from bacteria, but rather than directly implanting those beneficial attributes, he created mechanisms within the various hominin/homo groups to allow natural living development.
Human evolution; neonatal human and Neanderthal brains
DAVID: What I believe is God guided evolution constantly or with much pre-programming or pre-planning.
dhw: The only way your God could “guide evolution constantly” is through preprogramming or dabbling. So do you think he preprogrammed or dabbled every single “enormous” whale change in order to cover the time he had decided to take before embarking on achieving his one and only purpose – the design of H. sapiens? And would you agree that since these enormous changes were “adaptations”, it is difficult to draw a borderline between adaptation and innovation as processes that lead to speciation?
DAVID: You are confusing two words: as I use them adaptation is the same species sightly adjusted. Innovation creates a new species.
Your exact words were:
DAVID: Another partial step as whales adapted more fully to living in water, which required an enormous number of physical and physiological changes.
So which changes between land-based pre-whale and modern whale do you consider to have been innovations and not adaptations?
dhw: …please explain your theory of why he needed to preprogramme/dabble all the different stages of whale in order to cover the time he had decided not to achieve his “final goal”, and why he needed to preprogramme or dabble all the different and now extinct forms of human if all he wanted was us and he was always in charge.
DAVID: Covered all of this before. The different final forms lived in different environments and with interbreeding brought different beneficial attributes to the human final product. It is quite clear to me God knew how to evolve humans from bacteria, but rather than directly implanting those beneficial attributes, he created mechanisms within the various hominin/homo groups to allow natural living development.
What does “natural living development” mean? I thought you thought your God preprogrammed or dabbled every single “beneficial attribute” that contributed to the design of his one and only purpose: H. sapiens. If he allowed “natural living development”, with all sorts of hominins and humans coming and going but contributing different bits and pieces while other bits and oieces got left out, I can't help wondering how this could possibly fit in with the concept of a God who is in total charge, has only one purpose, and knows exactly how to achieve it. I’m not surprised that you have “no idea” why your God would have chosen such a roundabout method of achieving his one and only goal. Maybe he had something else in mind. (See "David’s theory of evolution".)
Human evolution; neonatal human and Neanderthal brains
by David Turell , Sunday, December 15, 2019, 15:41 (1803 days ago) @ dhw
DAVID: What I believe is God guided evolution constantly or with much pre-programming or pre-planning.
dhw: The only way your God could “guide evolution constantly” is through preprogramming or dabbling. So do you think he preprogrammed or dabbled every single “enormous” whale change in order to cover the time he had decided to take before embarking on achieving his one and only purpose – the design of H. sapiens? And would you agree that since these enormous changes were “adaptations”, it is difficult to draw a borderline between adaptation and innovation as processes that lead to speciation?
DAVID: You are confusing two words: as I use them adaptation is the same species slightly adjusted. Innovation creates a new species.
Your exact words were:
DAVID: Another partial step as whales adapted more fully to living in water, which required an enormous number of physical and physiological changes.
dhw: So which changes between land-based pre-whale and modern whale do you consider to have been innovations and not adaptations?
Still word games. If the changes were large enough, we would call it a new species! I'll stick to my view of the words.
dhw: …please explain your theory of why he needed to preprogramme/dabble all the different stages of whale in order to cover the time he had decided not to achieve his “final goal”, and why he needed to preprogramme or dabble all the different and now extinct forms of human if all he wanted was us and he was always in charge.DAVID: Covered all of this before. The different final forms lived in different environments and with interbreeding brought different beneficial attributes to the human final product. It is quite clear to me God knew how to evolve humans from bacteria, but rather than directly implanting those beneficial attributes, he created mechanisms within the various hominin/homo groups to allow natural living development.
dhw: What does “natural living development” mean? I thought you thought your God preprogrammed or dabbled every single “beneficial attribute” that contributed to the design of his one and only purpose: H. sapiens. If he allowed “natural living development”, with all sorts of hominins and humans coming and going but contributing different bits and pieces while other bits and oieces got left out, I can't help wondering how this could possibly fit in with the concept of a God who is in total charge, has only one purpose, and knows exactly how to achieve it. I’m not surprised that you have “no idea” why your God would have chosen such a roundabout method of achieving his one and only goal. Maybe he had something else in mind. (See "David’s theory of evolution"
No, it is quite obvious God had Denisovans and Neanderthals to develop different attributes to then contribute to human genomes in helpful ways. The literature I read is full of comments about this. I note you are still fully into God's mind with humanizing questions. I just look at what we know from history and note obvious explanations, as I just gave.
Human evolution; neonatal human and Neanderthal brains
dhw: (re the evolution of whales:)... would you agree that since these enormous changes were “adaptations”, it is difficult to draw a borderline between adaptation and innovation as processes that lead to speciation?
DAVID: You are confusing two words: as I use them adaptation is the same species slightly adjusted. Innovation creates a new species.
dhw: So which changes between land-based pre-whale and modern whale do you consider to have been innovations and not adaptations?
DAVID: Still word games. If the changes were large enough, we would call it a new species! I'll stick to my view of the words.
It is far from being a word game! You have acknowledged here (though you keep changing your mind on the Shapiro thread) that organisms adapt autonomously, but we can only observe minor changes. The Shapiro theory (and mine) depends on the autonomous ability of intelligent cells to make the major changes (innovations) that lead to speciation. My point is that there is no clear borderline between adaptation and innovation, and so the same mechanism may be responsible for both. Therefore I’m asking you to use our whale example to see if you yourself can draw a borderline. Why are you so reluctant to answer?
DAVID: It is quite clear to me God knew how to evolve humans from bacteria, but rather than directly implanting those beneficial attributes, he created mechanisms within the various hominin/homo groups to allow natural living development.
dhw: What does “natural living development” mean? I thought you thought your God preprogrammed or dabbled every single “beneficial attribute” that contributed to the design of his one and only purpose: H. sapiens. If he allowed “natural living development”, with all sorts of hominins and humans coming and going but contributing different bits and pieces while other bits and pieces got left out, I can't help wondering how this could possibly fit in with the concept of a God who is in total charge, has only one purpose, and knows exactly how to achieve it. […]
DAVID: No, it is quite obvious God had Denisovans and Neanderthals to develop different attributes to then contribute to human genomes in helpful ways. The literature I read is full of comments about this. I note you are still fully into God's mind with humanizing questions. I just look at what we know from history and note obvious explanations, as I just gave.
I am not questioning the contribution Denisovans and Neanderthals made to H. sapiens! I am asking why your always-in-charge, all-knowing God would have chosen such a roundabout method of fulfilling his sole purpose. You have repeatedly confirmed that you have “no idea”, so maybe all these hominins and humans were part of a “natural living development”, as opposed to being preprogrammed 3.8 billion years ago or personally dabbled with by your God. Or maybe he was experimenting to find the formula that would give him the being he so wanted to create.
Human evolution; last of H. erectus on Earth
by David Turell , Wednesday, December 18, 2019, 22:34 (1800 days ago) @ dhw
A very careful timed study on Java:
https://cosmosmagazine.com/palaeontology/the-final-stand-of-homo-erectus?utm_source=Cos...
"The disputed age of the youngest known Homo erectus remains on the Indonesian island of Java has been revised, effectively ruling out any overlap between the archaic human species and anatomically modern humans.
***
"The bones in question – 12 skull caps and two lower leg bones – were discovered in the 1930s by Dutch explorers near the Solo River at Ngandong in Central Java.
***
"Homo erectus has emerged as the most widespread of our ancient relatives. Remains throughout Africa, in Georgia in the Caucasus, in eastern China and on the Indonesian archipelago as far east as Java are all now considered to have come from the same long-surviving species.
"The species emerged as far back as two million years ago, but exactly how long they persisted has been a mystery.
"By the look of the Ngandong remains, they belonged to some of latest surviving members of the species.
***
"To narrow the age estimate even further, the team excavated at sites upstream and downstream of Ngandong, gathering 52 age estimates in total from different terrace layers using a range of different dating techniques.
“It's a much bigger scale, much more comprehensive approach to establishing a chronology for this site than has ever been attempted before,” says Westaway.
"Each of these 52 age estimates had margins of error: some were minimum ages, others maximum. The team used Bayesian modelling to combine these estimates and arrived at a final approximate age for the bone bed of 117,000 to 108,000 years old.
"The finding suggests that Homo erectus lived on Java for more than 1.4 million years.
"The new date rules out any co-habitation on the island with anatomically modern humans, who only arrived in the area after about 75,000 years ago, and the possibility that Homo erectus met its end at the hands of modern humans.
"It doesn’t rule out interactions with other hominins, including Denisovans, says Westaway. Some scientists have even suggested that the changing appearance of Homo erectus over time could be sign of hybridisation rather than the simple march of evolution. (my bold)
"Finding evidence to back up such tantalising theories will, of course, require more work, says Westaway. Drawing a line under the last appearance of the species is a good start.
Comment: Like the Hobbits, isolation seems to have helped them to exist until more recent times. For me it calls into question Gould's punc-inc theory that isolation produces evolution. And think, they lived in the time of H. habilis, Neanderthal, and early H. sapiens. A bush of Homos, just like the bush of life. Evolution follows a bushy pattern.
Human evolution; last of H. erectus on Earth
by David Turell , Thursday, December 19, 2019, 15:59 (1799 days ago) @ David Turell
An interesting take on the last of erectus: climate change got them:
https://www.the-scientist.com/news-opinion/reanalyzed-fossils-could-be-last-knownhomo-e...
"Homo erectus fossil remains discovered decades ago in Central Java, Indonesia, represent the last known individuals of the ancient hominin species, according to a press release. The new findings help to clarify how long H. erectus existed. The species, which evolved 2 million years ago, was the first to walk upright and to migrate from Africa.
"Paleontologist Yan Rizal at Bandung Institute of Technology in Indonesia and colleagues used radioactive dating to analyze 12 skulls and two lower leg bones discovered between 1931 and 1933. Over the years, the age of these fossils has been difficult to determine due to the geological complexity of the excavation site, an area near the Solo River at Ngandong that was experiencing changes in environmental conditions when the hominins died during a mass death event. Previous estimates of the fossils’ age ranged widely, from 550,000 to 27,000 years old, but the analysis from Rizal and colleagues suggests the fossils are between 117,000 and 108,000 years old, representing the last known occurrence of H. erectus.
"These specimens confirm that the species likely went extinct due to climate change, study coauthor Russell Ciochon, a biological anthropologist at the University of Iowa, tells CNN. “The open woodland was replaced by a rainforest. No Homo erectus fossils are found after the environment changed, so Homo erectus likely was unable to adapt to this new rainforest environment,” he says."
Comment: No time for adaptation is suggested, or the species was incapable of adapting and remained the same for two million years. dhw thinks environmental changes drives speciation. Hmmmmm.
Human evolution; H. sapiens all across Africa
by David Turell , Wednesday, January 22, 2020, 19:33 (1765 days ago) @ David Turell
From 300,000 years ago, at least four different populations:
https://www.sciencenews.org/article/ancient-kids-dna-reveals-new-insights-how-africa-wa...
"'Analyses of the west-central African children’s DNA indicate that at least three major human lineages —ancestral to either today’s central African hunter-gatherers, southern African hunter-gatherers or all other present-day people — genetically diverged from each other in rapid succession between roughly 250,000 and 200,000 years ago.
"A fourth, previously unknown human population also emerged in that time span and left a small genetic mark on modern western and eastern Africans, a team led by evolutionary geneticists Mark Lipson and David Reich...,
***
"'That genetic evidence from the long-dead kids fits a scenario in which different Homo sapiens populations emerged in different parts of Africa as early as around 300,000 years ago, followed by a mixing and mingling of populations across the continent (SN: 9/28/17).
"'A previous genetic study, led by evolutionary geneticist Pontus Skoglund of the Francis Crick Institute in London, identified a human population originating more than 200,000 years ago that was ancestral to later rainforest hunter-gatherer groups in western and central sub-Saharan Africa. The new study provides further evidence for that ancestral line: Ancient children in the new study carried a minority of ancestry from those ancient forerunners of rainforest groups.
"'Genetic data in the new study provide “the only ancient DNA record from so far west in sub-Saharan Africa,” Skoglund says.
"'Lipson’s group extracted DNA from four children buried at Shum Laka, a rock-shelter in northwestern Cameroon. Excavations there in the 1980s and 1990s yielded stone tools and other artifacts from hunter-gatherers spanning the last 30,000 years. The site also served as a cemetery for extended families. A total of 18 human skeletons, most from children, have been unearthed at Shum Laka. Some burials date to about 8,000 years ago, others to around 3,000 years ago."
Comment: H. sapiens was all over Africa as the start of our species. Did the group appear just once and spread, or were there multiple appearances? The point is not clear to me but the 300,000 year-old group was found in the Morocco area.
Human evolution; human DNA has an immune system
by David Turell , Monday, January 27, 2020, 18:03 (1760 days ago) @ David Turell
Other than the usual known cells and antibodies, in general is anti-viral:
https://www.the-scientist.com/news-opinion/novel-dna-sensing-pathway-found-in-human-cel...
"Triggered by an enzyme called DNA protein kinase (DNA-PK), the newly found pathway is independent of the cGAS-STING pathway—until now considered the main regulator of mammalian innate immune responses to DNA—and is missing or inactive in mouse cells.
***
"First described in 2013, the cGAS-STING pathway plays a critical role in the cell’s innate immune reaction to viral infection. Upon detecting cytosolic DNA (usually a tell-tale sign of viral entry), the cGAS enzyme binds to the transmembrane protein STING to trigger the production of interferons and other antiviral responses.
***
"It’s not the first time DNA-PK has been implicated in antiviral defenses. The University of Cambridge’s Geoffrey Smith and Brian Ferguson reported in 2012 that DNA-PK in mouse and human cells could promote interferon production in response to transfection with foreign DNA. That study, however, concluded that DNA-PK was likely triggering the response via STING, not independently of it.
“'It’s nice to see that another group has found an important role for DNA-PK in sensing foreign DNA,” Smith tells The Scientist, adding that the Washington team’s paper presents “some data supportive” of the conclusion that the new pathway is STING-independent.
"He notes that assays the team carried out using DNA-PK inhibitors seemed to influence antiviral responses differently depending on cell type—a result that Stetson says might have do with interactions between the DNA-PK and gCAS-STING pathways in the various cell lines the team used. In some cases, “the two pathways may antagonize each other,” Stetson writes in an email to The Scientist. “It is something we are interested in pursuing.”
"Examining other mammalian cell lines, Stetson’s team detected evidence of the novel DNA-PK pathway in non-human primate cells and in rat cells. But the researchers couldn’t find the pathway in mouse cells, where most preclinical research on cGAS-STING therapies has been conducted." (my bold)
Comment: Note my bold. It is interesting that this ability is widely available at the primate level, but also in rats, a known species with close to human physiology. Another complex immune system must have been designed.
Human evolution; Africa has a Neanderthal mixture
by David Turell , Thursday, January 30, 2020, 20:28 (1757 days ago) @ David Turell
Just discovered, and a result of migrations between Africa and Europe:
https://www.sciencenews.org/article/new-genetic-analysis-reveals-modern-africans-have-s...
"People who migrated out of Africa around 60,000 to 80,000 years ago interbred with Neandertals. That set the stage for some human groups to return to Africa carrying Neandertal genes that spread throughout the continent, apparently because those genes proved beneficial to ancient Africans, researchers report January 30 in Cell.
"Sets of Neandertal gene variants inherited by modern Africans include genes involved in bolstering the immune system and modifying sensitivity to ultraviolet radiation, geneticist Joshua Akey of Princeton University and his colleagues found. Those genes presumably spread quickly once introduced to African humans. A new statistical approach for detecting ancient genetic material that’s still present in modern DNA, developed by Akey’s team, enabled this discovery. (my bold)
"The researchers’ new technique also detected a human journey out of Africa roughly 100,000 to 150,000 years ago that led to the introduction of human genes into Neandertals via interbreeding. Some African DNA that appeared at first to have been inherited from Neandertals actually came from those ancient humans when scrutinized more closely, the investigators say.
“'Our work highlights how humans and Neandertals interacted for hundreds of thousands of years, with populations dispersing out of and back into Africa,” Akey says. “Remnants of Neandertal DNA survive in every modern human population studied to date.”
***
"Neandertal DNA accounts for, on average, about 0.5 percent of individual Africans’ genetic inheritance, or genome, far more than reported in earlier studies, Akey’s team concludes. Most present-day people outside Africa carry about three times as much Neandertal DNA as Africans do, the researchers say. More than 94 percent of Neandertal DNA sequences detected in today’s Africans have also been observed in non-Africans, they say."
Comment: the presence of different Homo species developed advantages for the final sapiens results as noted in the story ab out better immunity and better protection from the sun.
Human evolution; earliest sapiens in Europe
by David Turell , Monday, May 11, 2020, 19:55 (1655 days ago) @ David Turell
Dated at 44-46,000 years ago:
https://www.sciencenews.org/article/earliest-known-humans-europe-bacho-kiro-bulgaria
"A tooth and six bone fragments found in a Bulgarian cave are the oldest directly dated remains of Homo sapiens in Europe, scientists say.
"Until now, most of the earliest fossils of humans on the continent ranged in age from around 45,000 to 41,500 years old. But those ages are based on dates for sediment and artifacts associated with the fossils, not the fossils themselves. The newfound remains date to between roughly 46,000 and 44,000 years ago, researchers report May 11 in Nature.
***
"The new discoveries at Bulgaria’s Bacho Kiro Cave have added evidence for a scenario in which African H. sapiens reached the Middle East approximately 50,000 years ago (SN: 1/28/15) and then rapidly dispersed into Europe (SN: 11/2/11) and Central Asia (SN: 10/22/14), the scientists conclude.
***
"What’s more, stone artifacts and personal ornaments found with the human fossils are the earliest examples of a shift in tool and ornament making from what’s known as the Initial Upper Paleolithic culture, Hublin and colleagues say. Along with several earlier European excavations, the new finds indicate that Initial Upper Paleolithic tools were made for only a few thousand years before being replaced by related implements from the Aurignacian culture, which dates to between 43,000 and 33,000 years ago (SN: 3/23/15).
"The newfound stone tools and pendants made from cave bear teeth appear to have inspired similar objects made a few thousand years later by western European Neandertals, Hublin says, suggesting that ancient humans in Bulgaria mingled with native Neandertals. “The Bacho Kiro cave provides evidence that pioneer groups of Homo sapiens brought new behaviors into Europe and interacted with local Neandertals,” Hublin says.
"Although that’s possible, Neandertals made jewelry out of eagle talons around 130,000 years ago (SN: 3/20/15). That’s long before when H. sapiens are generally thought to have first reached Europe, and thus Neandertals may not have been influenced by the newcomers’ ornaments, says paleoanthropologist Chris Stringer of the Natural History Museum in London, who did not participate in the new studies.
"Human groups that brought Initial Upper Paleolithic toolmaking to Europe may have been too small to stay or survive for long when confronted with larger numbers of Neandertals and frequent climate fluctuations at the time, Stringer suspects. For as yet unclear reasons, it was the Aurignacian toolmakers who first took root in Europe and witnessed “a physical but not genetic end” to Neandertals, some of whose DNA survived in H. sapiens as a result of previous interbreeding, he says (SN: 5/11/15)."
Comment: Erectus moved call over the world. At some point sapiens had to do the same.
Human evolution; early Asia spread
by David Turell , Tuesday, March 09, 2021, 21:24 (1353 days ago) @ David Turell
New found stone tools:
https://www.nationalgeographic.com/science/article/india-stone-tools-human-evolution-ar...
"The discovery, described in Nature on Wednesday, pushes back the start of what’s called the Middle Paleolithic culture in the region by more than a hundred thousand years. That, in turn, could reshape how scientists view the global spread of hominins—humans and their ancient relatives—before modern humans migrated out of Africa some 60,000 years ago.
“'This clearly shows that populations with this culture were present in most parts of South Asia, adapting to local factors and with tool types evolving and changing through time,” says Shanti Pappu of the Sharma Centre for Heritage Education in India, who led the most recent excavations at Attirampakkam.
"The find also deepens scientists’ view of how ancient hominins lived in South Asia, a region where the fossil record remains poorly understood.
***
"Genetic evidence shows that more than 90 percent of humans today descend from a small population of Homo sapiens that left Africa between 60,000 and 125,000 years ago. From there, they rapidly fanned out, reaching the tip of South America by 18,000 years ago.
"Some researchers suspected that this wave of Homo sapiens expanded so rapidly because they were armed with advanced stone tools superior to those of the earlier Acheulian culture, which is defined by bulky stone hand-axes and cleavers.
"To test this idea, archaeologists have tried to find and date stone tools around the world, to see when the tool transition occurred in different regions. Previous studies found that Middle Paleolithic tools didn’t enter India before 140,000 years ago.
"Recent research, however, is building the case that multiple waves of humans left Africa before the migration inscribed in our collective DNA. Just last week, research published in Science suggested that modern humans ventured into what’s now Israel as early as 180,000 years ago, earlier than previously thought.
***
"In this context, Attirampakkam is an Indian national treasure. First explored for scientific purposes by British geologist R.B. Foote in 1863, it’s one of the subcontinent’s few thoroughly excavated archaeological sites dated to more than a hundred thousand years old.
"For more than 20 years, Pappu’s team has worked at Attirampakkam to unravel its secrets, digging through 30 feet of sediment an inch at a time.
"It hasn’t been easy; they’ve had to cope with summer heat, cobras, and a shoestring budget. But in 2011, their efforts massively paid off, when they announced the discovery of Acheulian tools at Attirampakkam that are more than a million years old, far older than other similar sites in India.
"The site continued to offer surprises. To Pappu’s delight, her colleagues also found artifacts in the sediments above the Acheulian layers. But unlike those bulkier tools, some of the younger tools were slimmer flakes of stone that could have tipped spears, a calling card for the Middle Paleolithic.
***
"In all likelihood, Attirampakkam’s oldest Middle Paleolithic layer—and its stone tool contents—are at least 250,000 years old, the team reports.
***
“'We used to think that modern humans spread from Africa because they had some enormous technical advantage that let them replace ‘stupid’ archaic humans; we now know this is false,” says University of Wisconsin-Madison paleoanthropologist John Hawks, who wasn’t involved with the study.
"But many questions remain. For one, Pappu stresses that the identity of the tools’ creators is still unknown. And Petraglia, who reviewed the study, cautions that while the tools at Attirampakkam may resemble Middle Paleolithic tools found elsewhere, that doesn’t necessarily exclude the possibility that different peoples converged on similar solutions to common problems.
“'I don’t think this is necessarily an out-of-Africa event,” he says. “Rather than equating technologies from Europe to Africa to South Asia, you can also recast it as independent invention by large-brained early humans'.”
Comment: Early homos either had massive wanderlust or environmental problems that drove them. Like convergence why could there not have been different populations with the same new concepts?
Human evolution; lots of genetic mixing
by David Turell , Thursday, March 19, 2020, 20:56 (1708 days ago) @ David Turell
A new broad study of many populations:
https://www.newscientist.com/article/2238034-dna-analysis-reveals-just-how-intertwined-...
"Bergstrom and his colleagues sequenced the genomes of 929 people from 54 different populations across the globe, including in Europe, the Middle East, Africa, America, Central and South Asia, East Asia and Oceania.
"They discovered hundreds of thousands of new gene variants that were common in many of the populations they studied but that had previously been missed, due to a lack of DNA sequences from people of non-European descent in existing data sets.
"Among the new discoveries that Bergstrom and his colleagues made was the finding that there was probably much more mixture between different ancient human populations in Africa than suggested by previous studies. Rather than a diverging family tree, they found evidence for much more gene flow between different populations. “It’s more like a kind of intertangled mesh of branches,” says Bergstrom.
"This hints at how ancient humans migrated out of Africa. Rather than a population separating into two and never seeing each other again, people probably continued to move between groups in a much more complex way, he says.
"The team also found more detailed evidence of our ancient human ancestors mating with other hominids. We already knew that our ancestors mated with archaic human groups, including Neanderthals and Denisovans, but until now it wasn’t clear how frequently this occurred and whether they mated with some groups more than others.
"Bergstrom and his team were able to show that people from many different populations around the world today have the same segments of Neanderthal DNA in their genomes, but segments of Denisovan DNA differ between people in different populations. That suggests that our ancestors probably mated with a single Neanderthal group but with multiple Denisovans after migrating out of Africa."
Comment: My interpretation remains the same: God used the adaptive abilities of the various human groups to result in a final group of sapiens well prepared for a variety of climates, and infectious processes.
Human evolution; hunter-gatherer women warriors
by David Turell , Monday, April 27, 2020, 20:36 (1669 days ago) @ David Turell
Newly found evidence:
https://www.sciencenews.org/article/women-warriors-hunter-gatherers-battles-mongolia
"Women’s reputation as nurturing homebodies who left warfare to men in long-ago societies is under attack. Skeletal evidence from hunter-gatherers in what’s now California and from herders in Mongolia suggests that women warriors once existed in those populations.
***
"But skeletons of 128 of those hunter-gatherer women display damage from arrows and sharp objects such as knives comparable to skeletal injuries of 289 presumed male warriors, Pilloud and her colleagues found. Whether those women fought alongside men or carried out other dangerous battle duties, such as sneaking up on enemies to cut their bow strings, can’t be determined from their bones. Individuals in this sample came from 19 Native American groups in central California, and had lived in any of five time periods between around 5,000 and 200 years ago.
"Evidence analyzed by Pilloud’s team was part of a database of excavated skeletal remains from more than 18,000 central California hunter-gatherers assembled by study coauthor Al Schwitalla of Millennia Archaeological Consulting in Sacramento. A 2014 study directed by Schwitalla determined that 10.7 percent of males in the database had suffered injuries from sharp objects and projectile points, versus 4.5 percent of females. The new study finds similar patterns of those injuries on the skeletons of men and women.
"In wars between Native American tribes in California, women were often killed in surprise raids and other attacks, which may partly explain female injuries reported in the new study, says biological anthropologist Patricia Lambert of Utah State University.
***
"A second skeletal analysis suggests that nomadic herders in ancient Mongolia, bordering northern China, trained some women to be warriors during a time of political turbulence and frequent conflicts known as the Xianbei period, says anthropologist Christine Lee of California State University, Los Angeles. The Xianbei period ran from 147 to 552.
"In a study of nine individuals buried in a high-status Mongolian tomb from the Xianbei period, conducted by Lee and Cal State colleague Yahaira Gonzalez, two of three women and all six men displayed signs of having ridden horses in combat.
"That conclusion rests on three lines of evidence: bone alterations caused by frequent horse riding and damage from falls off horses; upper-body signatures of having regularly used bows to shoot arrows, including alterations of spots where shoulder and chest muscles attach to bone; and arrowhead injuries to the face and head. Because the tomb was previously looted, any war-related objects that may have been interred with the bodies are gone.
"In western Asia, archaeologists have uncovered potential graves of women warriors that include weapons and war gear,
"By around 900, written documents refer to Mongolian women who fought in wars, held political power and had diplomatic credentials, Lee says. Freedom for Mongolian women to pursue a variety of activities goes back at least to the Xianbei period, she suspects."
Comment: It changes our view of this form of societal groups, but I think the thought comes from a previous view of woman, while today we have boxing and wrestling women fully accepted.
Human evolution; hunter-gatherer women hunters
by David Turell , Thursday, June 29, 2023, 16:42 (511 days ago) @ David Turell
A new study showing women hunt, not just gather.
https://www.newscientist.com/article/2380011-the-myth-that-men-hunt-while-women-stay-at...
"The idea that men hunt while women stay at home is almost completely wrong, a review of foraging societies around the world has found. In fact, women hunt in 80 per cent of the societies looked at, and in a third of these societies women were found to hunt big game – animals heavier than 30 kilograms – as well as smaller animals.
"These findings are likely to be representative of all foraging societies past and present, says Cara Wall-Scheffler at the University of Washington in Seattle. “We have nearly 150 years of ethnographic studies sampled, we have every continent and more than one culture from every continent, and so I feel like we did get a pretty good swathe of what people do around the world,” she says.
"There was already growing evidence that women hunted in many cultures in the past. For instance, of 27 individuals found buried with hunting weapons in the Americas, nearly half were women, a 2020 study found. Yet researchers have been reluctant to conclude that these women were hunters.
***
"The team also looked at data on the size of animals hunted by women, which was recorded for 45 societies. In 46 per cent of cases it was small game such as lizards and rodents, 15 per cent medium game and 33 per cent large game. In 4 per cent of the societies women hunted game of all sizes.
'The analysis found that women’s hunting strategies were more flexible than men’s. “Women use a wider range of tools when they go hunting, they go out with a wider variety of people,” says Wall-Scheffler.
"They may hunt alone or with a male partner, other women, children or dogs, for instance, says Wall-Scheffler. While the bow and arrow was commonly used by female hunters around the world, she says, women also used knives, nets, spears, machetes, crossbows and more.
***
“'This paper represents a much-needed meta-analysis,” says Randy Haas at Wayne State University in Michigan, whose team carried out the study of burials in the Americas. “The findings, coupled with related archaeological findings, convincingly show that division of subsistence labour is much more variable than previously thought,” he says.
"Given that women did and do hunt in so many societies, Wall-Scheffler says she can’t explain why the popular notion is that only men hunt. “I don’t understand it,” she says. “I think it is just as remarkable that women with babies on their back are going out to shoot animals.'”
Comment: this represents a big change in our thinking. More male chauvinist thinking disappears.
Human evolution; violent or not
by David Turell , Friday, June 30, 2023, 17:43 (510 days ago) @ David Turell
Based on chimp and bonobo societies:
https://www.newscientist.com/article/2379915-ape-family-tree-suggests-human-ancestors-w...
"The last common ancestor of humans, chimpanzees and bonobos wasn’t especially prone to violence, according to a study attempting to reconstruct the evolution of warlike behaviour among apes. Hostility between groups of this ancestor may have been tempered by bonds between unrelated females, the study suggests – but researchers warn that its conclusions are highly speculative.
"The question of whether violence is integral to human nature has been debated for centuries. Biologists have tried to answer it by looking at chimpanzees, which, along with bonobos, are our closest relatives.
"All four subspecies of chimpanzee engage in gruesome violence between groups. Some biologists have noted parallels between this behaviour and human warfare, suggesting that the common ancestor of humans and chimpanzees must have been violent and aggressive.
***
"To get a broader view of the question, Opie and his colleagues collected data from 301 primate species on 13 traits linked to lethal violence, such as infanticide and male alliances. They traced the distribution of these behaviours across the evolutionary tree of primates and performed a statistical analysis to identify which behavioural traits were relevant to intergroup violence.
"They found that encounters between groups in the common ancestor of humans, chimpanzees and bonobos probably weren’t always hostile, as was previously thought.
***
"Opie and his colleagues found that the most recent ancestor we share with chimpanzees was probably the first ape that showed cooperation among unrelated females. They conclude that violence in males was kept at bay by such female alliances and the males having to cooperate to form coalitions.
***
"The method of using evolutionary trees to reconstruct what ancestral species were like is highly speculative for behavioural traits, says Michael Wilson at the University of Minnesota. “The social behaviour of the last common ancestor [of humans, bonobos and chimpanzees] cannot be deduced in the absence of a fossil record for this species,” he says. “Even with a fossil record, inferring the social behaviour of extinct species poses tremendous challenges.”
"The study’s conclusions are plausible, but highly speculative, says Steven Pinker, also at Harvard University. “When it comes to the last common ancestor between humans and chimps, their inferences essentially are driven by just three data points: humans, chimps and bonobos.”
"Surbeck thinks aspects of aggressive behaviour are inherent to any social-living species. “I think that comparisons with our closest living relatives show us that there is an inherent propensity for violence in the form of infanticide, male sexual violence against females and even killing. However, social and environmental and, in the case of humans, cultural factors determine whether those traits are selected for and manifest within a species or context,” he says."
Comment: this study relies on evolutionary traits passing down from previous species. Pure Darwin-speak. The key is our intellect. We know good and evil and temper our reactions. We are vastly different from our ancestors. The criticisms speak for themselves.
Human evolution; hunter-gatherer women hunters
by David Turell , Wednesday, October 18, 2023, 17:32 (400 days ago) @ David Turell
Further evidence women hunted and still hunt:
https://www.scientificamerican.com/article/the-theory-that-men-evolved-to-hunt-and-wome...
"Man the Hunter has dominated the study of human evolution for nearly half a century and pervaded popular culture. It is represented in museum dioramas and textbook figures, Saturday morning cartoons and feature films. The thing is, it's wrong.
"Mounting evidence from exercise science indicates that women are physiologically better suited than men to endurance efforts such as running marathons. This advantage bears on questions about hunting because a prominent hypothesis contends that early humans are thought to have pursued prey on foot over long distances until the animals were exhausted. Furthermore, the fossil and archaeological records, as well as ethnographic studies of modern-day hunter-gatherers, indicate that women have a long history of hunting game. We still have much to learn about female athletic performance and the lives of prehistoric women. Nevertheless, the data we do have signal that it is time to bury Man the Hunter for good.
***
"...the muscle fibers of females differ from those of males. Females have more type I, or “slow-twitch,” muscle fibers than males do. These fibers generate energy slowly by using fat. They are not all that powerful, but they take a long time to become fatigued. They are the endurance muscle fibers. Males, in contrast, typically have more type II (“fast-twitch”) fibers, which use carbohydrates to provide quick energy and a great deal of power but tire rapidly.
***
"If females are better able to use fat for sustained energy and keep their muscles in better condition during exercise, then they should be able to run greater distances with less fatigue relative to males. In fact, an analysis of marathons carried out by Robert Deaner of Grand Valley State University demonstrated that females tend to slow down less as the race progresses compared with males.
***
"Observations of recent and contemporary foraging societies provide direct evidence of women participating in hunting. The most cited examples come from the Agta people of the Philippines. Agta women hunt while menstruating, pregnant and breastfeeding, and they have the same hunting success as Agta men.
"They are hardly alone. A recent study of ethnographic data spanning the past 100 years—much of which was ignored by Man the Hunter contributors—found that women from a wide range of cultures hunt animals for food. Abigail Anderson and Cara Wall-Scheffler of Seattle Pacific University and their colleagues report that 79 percent of the 63 foraging societies with clear descriptions of their hunting strategies feature women hunters. The women participate in hunting regardless of their childbearing status. These findings directly challenge the Man the Hunter assumption that women's bodies and childcare responsibilities limit their efforts to gathering foods that cannot run away.
"So much about female exercise physiology and the lives of prehistoric women remains to be discovered. But the idea that in the past men were hunters and women were not is absolutely unsupported by the limited evidence we have. Female physiology is optimized for exactly the kinds of endurance activities involved in procuring game animals for food. And ancient women and men appear to have engaged in the same foraging activities rather than upholding a sex-based division of labor. It was the arrival some 10,000 years ago of agriculture, with its intensive investment in land, population growth and resultant clumped resources, that led to rigid gendered roles and economic inequality.
"Now when you think of “cave people,” we hope, you will imagine a mixed-sex group of hunters encircling an errant reindeer or knapping stone tools together rather than a heavy-browed man with a club over one shoulder and a trailing bride. Hunting may have been remade as a masculine activity in recent times, but for most of human history, it belonged to everyone."
Comment: So much for the male-originated hunter-gatherer theory. The authors of this article have every right to complain.
Human evolution; Homo soloensis
by David Turell , Thursday, October 19, 2023, 17:32 (399 days ago) @ David Turell
A sample of erectus in Asia:
https://www.discovermagazine.com/the-sciences/who-was-homo-soloensis-the-solo-man?utm_s...
"In 1931, geologists excavated skull fragments from a fossil bed along the Solo River in Java, an Indonesian island under Dutch colonial rule. Over the next two years, they uncovered 10 more skull specimens and two pieces from a tibia. The geologists identified the bones as belonging to a previously undiscovered ancient human, Homo soloensis.
"Solo Man, as the specimen came to be known, has been a point of curiosity among archaeologists ever since its discovery. The hominid resembled ancient human lineages more closely than modern-day humans, even though researchers found it in a relatively young fossil bed.
***
"H. soloensis, the species name initially given to Solo Man, is now considered a misnomer. Solo Man actually belongs to a far older human lineage — Homo erectus. In many ways, this makes the hominid even more remarkable.
"Members of H. erectus migrated to Europe and Asia around 1.8 million years ago. Solo Man likely evolved from “Java Man,” the oldest H. erectus specimen found on the island. Java was the southeast terminus of the H. erectus migration, making Javaan H. erectus the furthest-traveled member of the species.
"To date, Solo Man is the last-known surviving member of H. erectus. The hominid outlived its cousins throughout Africa, Asia and Europe.
"Attempts at dating Solo Man fossils produced widely varying results. The Dutch geologists who made the discovery thought that the fossils were less than 150,000 years old due to the other fossils found at the site. In the ‘80s, ‘90s and 2000s, researchers used varying techniques to try to pin down Solo Man’s age. All of the results placed the fossils at around 70,000 years to 40,000 years old. If the findings were true, this would mean that Solo Man likely lived alongside prehistoric Homo sapiens, who likely migrated to Southeast Asia around 60,000 years ago.
"However, an extensive analysis of fossils from the region, published by an international research group in 2019, revealed that Solo Man was older than previously thought — 117,000 years to 108,000 years old. So, Solo Man did not overlap with H. sapiens in Southeast Asia. But, the hominid probably coincided with other ancient humans in the area, such as the ancient pygmies discovered on the Indonesian island of Flores."
Comment: Erectus migrated Eastward out of Africa finally reaching the Western Hemisphere 20,000+ years ago. It is obvious various subcultures coexisted along the way and may well have comingled.
Human evolution; reaching North America
by David Turell , Sunday, December 17, 2023, 18:56 (340 days ago) @ David Turell
About 24,000 years ago:
https://phys.org/news/2023-12-north-america-people-sea-ice.html
"...a growing number of archaeological and genetic finds—including human footprints in New Mexico dated to around 23,000 years old—suggests that people made their way onto the continent much earlier. These early Americans likely traveled along the Pacific coastline from Beringia, the land bridge between Asia and North America that emerged during the last glacial maximum when ice sheets bound up large amounts of water causing sea levels to fall.
"Now, in research to be presented Friday, 15 December at the American Geophysical Union Annual Meeting (AGU23) in San Franciso, paleoclimate reconstructions of the Pacific Northwest hint that sea ice may have been one way for people to move farther south.
"The idea that early Americans may have traveled along the Pacific Coast isn't new. People were likely south of the massive ice sheets that once covered much of the continent at least 16,000 years ago.
"Given that the ice-free corridor wouldn't be open for thousands of years before these early arrivals, scientists instead proposed that people may have moved along a "kelp highway." This theory holds that early Americans slowly traveled down into North America in boats, following the bountiful goods found in coastal waters.
***
"Arctic people today travel along sea ice on dog sleds and snow mobiles. Early Americans may also have used the 'sea ice highway' to get around and hunt marine mammals, slowly making their way into North America in the process, Praetorius said. The climate data suggest conditions along the coastal route may have been conducive to migration between 24,500 and 22,000 years ago and 16,400-14,800 years ago, possibly aided by the presence of winter sea ice.
"While proving that people were using sea ice to travel will be tricky, given most of the archaeological sites are underwater, the theory provides a new framework for understanding how humans may have arrived in North America without a land bridge or easy ocean travel."
Comment: if footprints are 23,000 years old the folks were here. It is how that is the problem.
Human evolution; breast feeding helps brain development.
by David Turell , Sunday, December 17, 2023, 19:23 (340 days ago) @ David Turell
A current study:
https://www.sciencedaily.com/releases/2023/12/231213155222.htm
"Breastfeeding, even partially alongside formula feeding, changes the chemical makeup -- or metabolome -- of an infant's gut in ways that positively influence brain development and may boost test scores years later, suggests new research.
"Breastfeeding, even partially alongside formula feeding, changes the chemical makeup -- or metabolome -- of an infant's gut in ways that positively influence brain development and may boost test scores years later, suggests new CU Boulder research.
"'For those who struggle with exclusively breastfeeding, this study suggests your baby can still get significant benefits if you breastfeed as much as you can," said senior author Tanya Alderete, an assistant professor of integrative physiology at CU Boulder.
***
"For the study, the research team examined what is known as the "fecal metabolome" -- the diverse collection of metabolites found in the gut and shed in poop. Metabolites are small molecules that are churned out by gut bacteria as a byproduct of metabolizing food and make their way into the bloodstream, impacting the brain and other organs.
***
"'Looking at the gut microbiome tells us which bacteria are there, while looking at the fecal metabolome can help tell us what they are doing," said Chalifour. "It's like a health report card for the gut."
***
"With only one notable exception, caffeine, the more metabolites associated with breast milk a baby had in their stool, the better they did on cognitive tests as toddlers.
"The more metabolites associated with formula feeding they had, the worst they did.
"'The consistency of these results is striking and supports the benefits of breastfeeding as much as possible in early life," said Alderete.
"One particularly beneficial metabolite was cholesterol: At both 1 and 6 months old, the more a baby was breastfed the more cholesterol they had in their stool. And the more cholesterol babies had in their stool, the better they did on cognitive tests. This makes sense, as the fatty acid is critical for forming healthy circuits between brain cells. As the authors note, 80% to 90% of the brain's volume grows in the first two years of life.
"In contrast, the more a baby was formula fed, the higher their levels of a metabolite called cadaverine, a known contaminant formed via fermentation."
Comment: that breast feeding is better for babies is an obvious guess assuming evolution works for the best. This proves it.
Human evolution; hunter-gatherers still exist today
by David Turell , Tuesday, March 05, 2024, 17:26 (261 days ago) @ David Turell
By choice of the individuals:
https://aeon.co/essays/the-hunter-gatherers-of-the-21st-century-who-live-on-the-move?ut...
Previous research on these societies from the 18th and 19th centuries had often portrayed them as primitive leftovers from a less developed past, who struggled to gather resources during their short, difficult lives. This early research supported an array of racist ideas about human evolution and emboldened forms of social Darwinism that were used to justify a view of hunter-gatherers as less than human, which helped lay the ‘moral’ ground for the displacement and colonisation of hunter-gatherer populations around the world.
***
The movement of hunter-gatherers may explain the emergence of complex, cumulative culture and our ability to maintain high levels of genetic diversity, even when population sizes drop to very, very low numbers. Far from representing an obsolete mode of living, mobility may hold the key to the continuing survival of these populations, despite pressures to settle. These societies are not the remnants of an outdated, ancient way of life from the distant past. For many hunter-gatherers living in the 21st century, staying mobile is a deliberate choice because it enables large and complex societies – societies that look more like mobile constellations than villages or cities.
***
In the 21st century, hunter-gatherers continue to choose a life of almost-perpetual motion not only so they can find resources. They remain mobile so they can participate in large and complex societies distributed across territories that rival the size of Earth’s largest cities.
***
The specific locations of these camps were strategically selected, they said, to help with the hunting of small game. The rainy season had now passed, and we were arriving at the end of the fishing season, called kombi, which lasts for around two months, typically from January to February. With the change in season, most Mbendjele BaYaka families had temporarily relocated near the region’s main river, the Motaba.
***
These agriculturalist populations spread across and eventually dominated the African continent...In central Africa today, there are still many hunter-gatherer groups, but this is not the case elsewhere in Africa. In the Congo Basin, only 20 or so cultural groups still practise hunting and gathering as their primary means of subsistence.
***
Today, an estimated 250,000 to 350,000 people subsist mainly from hunting and gathering across the Congo Basin, despite strong government efforts, beginning in the 1950s across Central Africa, resulting in many being settled into villages or absorbed into the surrounding market economies. These hunter-gatherers often change residence, are mostly egalitarian, and practise sharing not as a choice but an obligation. Although they are in regular contact with surrounding farming populations, to the point that they even speak their languages, and exchange objects, food and other forest products with them for market goods, they have managed to maintain their way of life for hundreds of thousands of years.
***
However, Central African hunter-gatherers have lived in very similar ways for more than 100,000 years. Despite dominant narratives about human evolution, these small bands have managed to continue their way of life into the 21st century. And even though they are sometimes surrounded by settled societies, they have chosen not to transition to agriculture, not to accumulate goods, not to live in larger groups, and not avoid the difficulties of staying mobile.
***
societies that were at one stage fully reliant on agriculture later returned to hunting and gathering. Perhaps one of the most interesting examples is that of the Numic-speaking hunter-gatherer groups of the Great Basin (including California), such as the Shoshone. These groups, who were biological and linguistic descendants of the original maize-cultivators in Mexico and the Southwestern United States, completely abandoned their agricultural lifestyle around 1,000 years ago.
***
Based on this evidence, the Mbendjele BaYaka and other groups in the Congo Basin did not simply move because food ran out. They moved because they were part a mobile society that was large, complex and distributed.
***
The emergence and propulsion of complex culture was not the only reason why hunter-gatherers have stayed mobile. Another crucial reason is to look for spouses from different regions, with populations often having explicit rules prohibiting marriage between people from the same community.
***
Settled agriculture is not a checkpoint on a one-way road to progress. Mobile societies have always been part of our success as a species, and they continue to structure our story, even today as 21st-century hunter-gatherers choose a mobile way of life.
***
‘Suppose somebody dies,’ an elderly Mbendjele healer named Phata explained to his anthropologist friend Jerome Lewis in 1997. ‘Their body goes into the earth. Dead people do not come out again.’ In the ground, your body changes, Phata said. ‘But your spirit, it goes walking, it goes walking, it goes walking, it goes walking.’
Comment: it explains the wandering migration eastward from Africa to the western hemisphere
Human evolution; hunter-gatherers still exist today
QUOTE: Today, an estimated 250,000 to 350,000 people subsist mainly from hunting and gathering across the Congo Basin, despite strong government efforts, beginning in the 1950s across Central Africa, resulting in many being settled into villages or absorbed into the surrounding market economies. These hunter-gatherers often change residence, are mostly egalitarian, and practise sharing not as a choice but an obligation. Although they are in regular contact with surrounding farming populations, to the point that they even speak their languages, and exchange objects, food and other forest products with them for market goods, they have managed to maintain their way of life for hundreds of thousands of years.
Thank you for this wonderful article, which I find both enlightening and moving. Here we have a form of human society that probably comes as close as possible to ideal. Gone is the emphasis on personal power and wealth which leads to so much strife in our own society. In this sense, it seems quite naturally to have achieved many of the ideals aspired to by Buddhist philosophy. Even if the hunter-gatherers now exchange goods with neighbouring farmers, they are not dependent on a market economy controlled by impersonal corporations. And they have oneness instead of conflict with nature, no crime, no envy, no war...I googled the whole article, and was struck by the scene conjured up at the very beginning:
“Less than a year ago, we had walked these same muddy trails, travelling each day to a temporary Mbendjele BaYaka settlement in the Congo rainforest. Back then, the settlement buzzed with children’s laughter. Women organised expeditions to gather firewood or helped collect payo (a bush mango) with the men who hadn’t left camp to try their luck catching an antelope.”
Idyllic. Has it been romanticized? I don’t think so, since it has survived for so long despite "strong government efforts" to destroy it. Why should it be destroyed? One look at the misery and chaos of the world we so-called “civilised” people have created should be enough to tell us that we have no right to look down on the hunter-gatherers, let alone to put an end to their culture.
But of course we can’t go back now. Our civilisation has progressively shrunk the world and narrowed its focus to harnessing nature instead of cooperating with it. We institutionally poison our food, pollute our air, murder, starve and exploit one another, all for the sake of profit or power. And this is now our normality. That is not to say that we have killed all joy. There is still love, empathy, art, philanthropy, humour etc. to give us the chance of happiness. But I suspect that the hunter-gatherers can teach us far more than we can teach them.
Human evolution; hunter-gatherers still exist today
by David Turell , Wednesday, March 06, 2024, 16:55 (260 days ago) @ dhw
QUOTE: Today, an estimated 250,000 to 350,000 people subsist mainly from hunting and gathering across the Congo Basin, despite strong government efforts, beginning in the 1950s across Central Africa, resulting in many being settled into villages or absorbed into the surrounding market economies. These hunter-gatherers often change residence, are mostly egalitarian, and practise sharing not as a choice but an obligation. Although they are in regular contact with surrounding farming populations, to the point that they even speak their languages, and exchange objects, food and other forest products with them for market goods, they have managed to maintain their way of life for hundreds of thousands of years.
dhw: Thank you for this wonderful article, which I find both enlightening and moving. Here we have a form of human society that probably comes as close as possible to ideal. Gone is the emphasis on personal power and wealth which leads to so much strife in our own society. In this sense, it seems quite naturally to have achieved many of the ideals aspired to by Buddhist philosophy. Even if the hunter-gatherers now exchange goods with neighbouring farmers, they are not dependent on a market economy controlled by impersonal corporations. And they have oneness instead of conflict with nature, no crime, no envy, no war...I googled the whole article, and was struck by the scene conjured up at the very beginning:
“Less than a year ago, we had walked these same muddy trails, travelling each day to a temporary Mbendjele BaYaka settlement in the Congo rainforest. Back then, the settlement buzzed with children’s laughter. Women organised expeditions to gather firewood or helped collect payo (a bush mango) with the men who hadn’t left camp to try their luck catching an antelope.”
dhw: Idyllic. Has it been romanticized? I don’t think so, since it has survived for so long despite "strong government efforts" to destroy it. Why should it be destroyed? One look at the misery and chaos of the world we so-called “civilised” people have created should be enough to tell us that we have no right to look down on the hunter-gatherers, let alone to put an end to their culture.
dhw: But of course we can’t go back now. Our civilisation has progressively shrunk the world and narrowed its focus to harnessing nature instead of cooperating with it. We institutionally poison our food, pollute our air, murder, starve and exploit one another, all for the sake of profit or power. And this is now our normality. That is not to say that we have killed all joy. There is still love, empathy, art, philanthropy, humour etc. to give us the chance of happiness. But I suspect that the hunter-gatherers can teach us far more than we can teach them.
Glad you read the article in its whole import. Your comments are exactly on point. But think about it, it is a romanticized sort of life in the article, but it is a hard life in actuality. I doubt they have our longevity.
Human evolution; stone tools in Ukraine million years old
by David Turell , Wednesday, March 06, 2024, 17:30 (260 days ago) @ dhw
Age just discovered:
https://www.usnews.com/news/news/articles/2024-03-06/ancient-stone-tools-found-in-ukrai...
"Ancient stone tools found in western Ukraine may be the oldest known evidence of early human presence in Europe, according to research published Wednesday in the journal Nature.
"The chipped stones, deliberately fashioned from volcanic rock, were excavated from a quarry in Korolevo in the 1970s. Archaeologists used new methods to date the layers of sedimentary rock surrounding the tools to more than 1 million years old.
"'This is the earliest evidence of any type of human in Europe that is dated,” said Mads Faurschou Knudsen, a geophysicist at Aarhus University in Denmark and co-author of the new study.
"He said it's not certain which early human ancestors fashioned the tools, but it may have been Homo erectus, the first species to walk upright and master the use of fire.
“'We don’t have fossil remains, so we can’t be sure,” said Roman Garba, an archaeologist at the Czech Academy of Sciences and co-author.
"The chipped stone tools were likely used for cutting meat and perhaps scraping animal hides, he said.
"The researchers suggest the tools may be as old as 1.4 million years, but other experts say the study methodology suggests that they may be just over 1 million years old, placing them in roughly the same date range as other ancient tools unearthed in Spain.
"The very earliest stone tools of this type were found in eastern Africa and date back to 2.8 million years ago, said Rick Potts, who directs the Smithsonian Institution's Human Origins Program.
"The Ukraine site is significant because “it's the earliest site that far north,” suggesting that the early humans who dispersed from Africa with these tools were able to survive in diverse environments.
“'The oldest humans with this old stone tool technology were able to colonize everywhere from warm Iberia (Spain) to Ukraine, where it's at least seasonally very cold – that’s an amazing level of adaptability,” said Potts."
Comment: As in the article about hunter-gatherers, our ancestors kept migrating.
Human evolution; how our outer skin works
by David Turell , Saturday, March 14, 2020, 22:30 (1713 days ago) @ dhw
It is a progression of inner cells finally migrating to the outside and forming a barrier:
https://www.sciencedaily.com/releases/2020/03/200313155327.htm
"Skin is our body's most ardent defender against pathogens and other external threats. Its outermost layer is maintained through a remarkable transformation in which skin cells swiftly convert into squames -- flat, dead cells that provide a tight seal between the living portion of the skin and the world outside.
"'Throughout our lifetime, squames are continually being shed from the skin surface and replaced by inner cells moving outward," says Elaine Fuchs, Rockefeller's Rebecca C. Lancefield Professor, whose lab recently shed new light onto this process. "We've identified the mechanism that allows skin cells to sense new changes in their environment and very quickly deploy instructions to drive squame formation."
***
"The skin's epidermis consists of an inner layer of stem cells that periodically stop dividing and move outward, toward the body surface. As the cells transit through subsequent layers, they face the increasingly harsh extremes of our environment, like variations in temperature. In the very last step, as they approach the surface, the cells' nuclei and organelles are suddenly lost in the dramatic transformation into squames.
***
"With this method, [skipped over above] the researchers were able to show that a protein called filaggrin, which is known to be mutated in some skin conditions, plays a key role in granule formation. "If filaggrin is not functioning properly, phase separation fails to occur, skin lacks keratohyalin granules, and the cells can no longer transform in response to environmental triggers," says Quiroz."
Comment: As this shows all processes in life are guided succession of planned events.
Human evolution; earliest known civilization
by David Turell , Friday, March 20, 2020, 14:20 (1707 days ago) @ David Turell
An archaeological find in China, about 5,500 year old city:
https://www.newscientist.com/article/mg24532740-700-the-stunning-east-asian-city-that-d...
"The stunning east Asian city that dates to the dawn of civilisation
The mysterious Liangzhu civilisation was a neolithic "Venice of the East", rivalling ancient Egypt and Mesopotamia with its engineering marvels
"NEARLY five-and-a-half millennia ago, a bustling metropolis lay in the delta of the lower Yangtze, in what is now China. You could enter on foot – there was a single road through the towering city walls – but most people travelled by boat via an intricate network of canals. At its heart, was a massive palatial complex built on a platform of earth. There were huge granaries and cemeteries filled with elaborately decorated tombs, while the water system was controlled by an impressive series of dams and reservoirs.
"The inhabitants of this city, known today as Liangzhu, ruled the surrounding floodplains for nearly 1000 years, their culture extending into the countryside for hundreds of kilometres. Then, around 4300 years ago, the society quickly declined, and its achievements were largely forgotten. It is only within the past decade that archaeologists have begun to reveal its true importance in world history.
"Their startling discoveries suggest that Liangzhu was eastern Asia’s oldest state-based society, and its infrastructure may even have surpassed the achievements of Egypt and Mesopotamia, thousands of miles to the west. “There’s nothing in the world, from my vantage point, that is as monumental in terms of water management – or for that matter, any kind of management – that occurs so early in history,” says Vernon Scarborough at the University of Cincinnati in Ohio."
Comment: Homo Sapiens appeared 315,000 years ago. A very slow mental development until the recent exponential growth. While the brain shrunk by 150 cc in the past 35,000 years as the brain/soul developed millions of new concepts. Concepts do not grow brains. Concepts are developed through the use of more complex brains.
Human evolution; weightlifting grows bigger bones
by David Turell , Tuesday, March 21, 2023, 23:48 (610 days ago) @ David Turell
No question:
https://www.realclearscience.com/blog/2023/03/22/the_most_important_benefit_of_weight_l...
"Building buffness. Getting ripped. Toning up. No matter what it’s called, becoming more muscular is generally top-of-the-mind for any young person who regularly visits the weight room. Less thought about is another key benefit, one that’s not as easily seen but is more long-lasting and consequential: weight training is the best way to strengthen bones.
"The stress placed on bones by squatting, pressing, deadlifting, pulling, or doing pretty much any motion with added resistance kicks bone-synthesizing cells called osteoblasts into high gear. They start producing collagen, other specialized proteins, and hydroxyapatite — the bone mineral — and forming these raw materials into more bone for your spine, femur, tibia, and any other bones that are bearing the added weight. The result is a stronger skeleton, one more resistant to fracture.
"As your skeleton is literally the foundational structure of your body, that’s a big deal. The average person loses about 1% of their bone mass each year after age forty. For about three million Americans each year, this decline eventually results in a potentially debilitating condition called osteoporosis, in which bones become so weak and brittle that a fall or even a mild stressor like bending over or coughing can cause them to crack. Two million osteoporosis-related fractures occur each year, sometimes resulting in permanent enfeeblement. According to Harvard Medical School, “six out of 10 people who break a hip never fully regain their former level of independence”.
***
"A measured weight training program, starting at two days per week of exercises targeting the entire body, broken down into eight to twelve repetitions of two sets per exercise at a manageable resistance on fixed machines, and gradually building up to greater loads with fewer repetitions performed using free-moving weights, can put anyone on the path to more durable, buffer bones.
"This skeletal strengthening occurs at any age, but it is most pronounced early in life. In fact, the (understandably) superficial young people referenced at the beginning of the article might want to take note of something a team of endocrinologists wrote in 2018:
“'While there is no clear evidence from life-long studies, it is suggested that adaptations to mechanical loading in youth are translated to greater bone strength over a lifetime. Bones become less sensitive to mechanical loading after skeletal maturity is reached at 18 to 25 years of age.”
"Muscle comes and goes, but bones could last forever."
Comment: Any aspect of our health is improved by working that part of the body. That adaptability is built int our design.
Human evolution; traits from many points in DNA
by David Turell , Friday, May 17, 2019, 18:26 (2015 days ago) @ David Turell
Very hard to analyze:
https://www.quantamagazine.org/new-turmoil-over-predicting-the-effects-of-genes-20190423/
"many have become optimistic about the prospects for disentangling the threads of “nature” and “nurture” — that is, about determining the extent to which genes alone can explain differences within and between populations.
***
"A key breakthrough was the recent development of genome-wide association studies (GWAS, commonly pronounced “gee-wahs”). The genetics of simple traits can often be deduced from pedigrees, and people have been using that approach for millennia to selectively breed vegetables that taste better and cows that produce more milk. But many traits are not the result of a handful of genes that have clear, strong effects; rather, they are the product of tens of thousands of weaker genetic signals, often found in noncoding DNA. When it comes to those kinds of features — the ones that scientists are most interested in, from height, to blood pressure, to predispositions for schizophrenia — a problem arises. Although environmental factors can be controlled in agricultural settings so as not to confound the search for genetic influences, it’s not so straightforward to extricate the two in humans.
***
"two results published last month have cast doubt on those findings, and have illustrated that problems with interpretations of GWAS results are far more pervasive than anyone realized. The work has implications for how scientists think about the interactions between genetic and environmental effects. It also “raise[s] the ghosts of the possibility that we overestimate … how important genetics is in contributing to differences between people,” said Rasmus Nielsen, a biologist at the University of California, Berkeley.
***
"Five years ago, a series of analyses on a European database made these dreams seem within reach. People of northern European ancestry are on average taller than those of southern European ancestry. Researchers wanted to explore whether those differences were a result of natural selection. They found that the polygenic scores for height did indeed increase from southern to northern Europe, much more so than would be expected from the random fluctuations in variant frequencies called genetic drift.
***
"But the scientists had ways to correct for those biases, and the signal of selection on height remained. “We were really excited about that, because we were finally getting to look at … adaptation operating on complex traits,” said Graham Coop,
***
“'The new studies are really quite disconcerting,” Barton said, because they demonstrated that scientists had been mistaking biases in the polygenic score calculations for something biologically interesting. Their statistical methods of accounting for population structure were not so adequate after all.
***
"Barton agreed. “The whole thing is tricky, because the origins of genetic variation in any population are really complicated,” he said. “Now you really can’t take at face value any of these methods over the last four or five years that use polygenic scores.”
***
“'The methods developed so far really think about genetics and environment as separate and orthogonal, as independent factors. When in truth, they’re not independent. The environment has had a strong impact on the genetics, and it probably interacts with the genetics,” said Gil McVean, a statistical geneticist at the University of Oxford. “We don’t really do a good job of … understanding [that] interaction.'”
Comment: We really do not know how genes control traits. Environment plays an unknown degree of influence, as dhw notes Obviously the whole of DNA is involved; no support for the concept of 'junk'.
Human evolution; traits from many points in DNA
QUOTE: “'The methods developed so far really think about genetics and environment as separate and orthogonal, as independent factors. When in truth, they’re not independent. The environment has had a strong impact on the genetics, and it probably interacts with the genetics,” said Gil McVean, a statistical geneticist at the University of Oxford. “We don’t
really do a good job of … understanding [that] interaction.'”
DAVID: We really do not know how genes control traits. Environment plays an unknown degree of influence, as dhw notes.
Thank you for this gracious acknowledgement. All our discussions revolve around things “we really do not know”, but I don’t think it requires a great deal of thought, research and money to realize that interaction between the genome and the environment lies at the heart of evolution.
Human evolution; traits from many points in DNA
by David Turell , Saturday, May 18, 2019, 15:57 (2014 days ago) @ dhw
QUOTE: “'The methods developed so far really think about genetics and environment as separate and orthogonal, as independent factors. When in truth, they’re not independent. The environment has had a strong impact on the genetics, and it probably interacts with the genetics,” said Gil McVean, a statistical geneticist at the University of Oxford. “We don’t
really do a good job of … understanding [that] interaction.'”DAVID: We really do not know how genes control traits. Environment plays an unknown degree of influence, as dhw notes.
dhw: Thank you for this gracious acknowledgement. All our discussions revolve around things “we really do not know”, but I don’t think it requires a great deal of thought, research and money to realize that interaction between the genome and the environment lies at the heart of evolution.
What is at the heart of driving evolution is God. What environment does, and I include competition with other organisms under the environment umbrella, is species adaptation to the problems presented, nothing more.
Human evolution; traits from many points in DNA
DAVID: We really do not know how genes control traits. Environment plays an unknown degree of influence, as dhw notes.
dhw: Thank you for this gracious acknowledgement. All our discussions revolve around things “we really do not know”, but I don’t think it requires a great deal of thought, research and money to realize that interaction between the genome and the environment lies at the heart of evolution.
DAVID: What is at the heart of driving evolution is God. What environment does, and I include competition with other organisms under the environment umbrella, is species adaptation to the problems presented, nothing more.
Even for someone who believes in God, it should be crystal clear that evolutionary adaptations and innovations must enable the organism to survive or improve its chances of survival in a given environment. Otherwise the adaptation/innovation is totally pointless. You claim your God turned pre-whale legs into flippers before sending the pre-whale into the water. The innovation/adaptation is still geared to a change of environment. I don’t know how many of your fellow theists will agree that your God preprogrammed or dabbled every change in advance of the new environmental conditions, but it makes no difference: the changing environment remains key to the progress of evolution as the trigger for anatomical change, whether by your God or by cellular intelligence. You have the added problem of deciding whether your God does or does not control every single environmental change that requires or allows for the anatomical changes which constitute speciation.
Human evolution; traits from many points in DNA
by David Turell , Thursday, May 23, 2019, 18:53 (2009 days ago) @ dhw
DAVID: We really do not know how genes control traits. Environment plays an unknown degree of influence, as dhw notes.
dhw: Thank you for this gracious acknowledgement. All our discussions revolve around things “we really do not know”, but I don’t think it requires a great deal of thought, research and money to realize that interaction between the genome and the environment lies at the heart of evolution.
DAVID: What is at the heart of driving evolution is God. What environment does, and I include competition with other organisms under the environment umbrella, is species adaptation to the problems presented, nothing more.
dhw: Even for someone who believes in God, it should be crystal clear that evolutionary adaptations and innovations must enable the organism to survive or improve its chances of survival in a given environment. Otherwise the adaptation/innovation is totally pointless. You claim your God turned pre-whale legs into flippers before sending the pre-whale into the water. The innovation/adaptation is still geared to a change of environment. I don’t know how many of your fellow theists will agree that your God preprogrammed or dabbled every change in advance of the new environmental conditions, but it makes no difference: the changing environment remains key to the progress of evolution as the trigger for anatomical change, whether by your God or by cellular intelligence. You have the added problem of deciding whether your God does or does not control every single environmental change that requires or allows for the anatomical changes which constitute speciation.
My belief is that God caused speciation. Darwin-style evolution is incapable of it.
Human evolution; traits from many points in DNA
dhw: I don’t think it requires a great deal of thought, research and money to realize that interaction between the genome and the environment lies at the heart of evolution.
DAVID: What is at the heart of driving evolution is God. What environment does, and I include competition with other organisms under the environment umbrella, is species adaptation to the problems presented, nothing more.
dhw: Even for someone who believes in God, it should be crystal clear that evolutionary adaptations and innovations must enable the organism to survive or improve its chances of survival in a given environment. Otherwise the adaptation/innovation is totally pointless. You claim your God turned pre-whale legs into flippers before sending the pre-whale into the water. The innovation/adaptation is still geared to a change of environment. I don’t know how many of your fellow theists will agree that your God preprogrammed or dabbled every change in advance of the new environmental conditions, but it makes no difference: the changing environment remains key to the progress of evolution as the trigger for anatomical change, whether by your God or by cellular intelligence. You have the added problem of deciding whether your God does or does not control every single environmental change that requires or allows for the anatomical changes which constitute speciation.
DAVID: My belief is that God caused speciation. Darwin-style evolution is incapable of it.
Yes, we know you think your God either preprogrammed or dabbled every single innovation, lifestyle and natural wonder, but this does not in any way reduce the importance of the environment’s influence on evolution, and it does not answer the question of whether your God deliberately engineered every single environmental change, both global and local. Please stick to the subject.
Human evolution; traits from many points in DNA
by David Turell , Friday, May 24, 2019, 19:34 (2008 days ago) @ dhw
dhw: I don’t think it requires a great deal of thought, research and money to realize that interaction between the genome and the environment lies at the heart of evolution.
DAVID: What is at the heart of driving evolution is God. What environment does, and I include competition with other organisms under the environment umbrella, is species adaptation to the problems presented, nothing more.
dhw: Even for someone who believes in God, it should be crystal clear that evolutionary adaptations and innovations must enable the organism to survive or improve its chances of survival in a given environment. Otherwise the adaptation/innovation is totally pointless. You claim your God turned pre-whale legs into flippers before sending the pre-whale into the water. The innovation/adaptation is still geared to a change of environment. I don’t know how many of your fellow theists will agree that your God preprogrammed or dabbled every change in advance of the new environmental conditions, but it makes no difference: the changing environment remains key to the progress of evolution as the trigger for anatomical change, whether by your God or by cellular intelligence. You have the added problem of deciding whether your God does or does not control every single environmental change that requires or allows for the anatomical changes which constitute speciation.
DAVID: My belief is that God caused speciation. Darwin-style evolution is incapable of it.
dhw: Yes, we know you think your God either preprogrammed or dabbled every single innovation, lifestyle and natural wonder, but this does not in any way reduce the importance of the environment’s influence on evolution, and it does not answer the question of whether your God deliberately engineered every single environmental change, both global and local. Please stick to the subject.
The subject is how speciation happens, and the question cannot be answered at this time, but we both have suggested logical possibilities..
Human evolution; new anthropological info
by David Turell , Thursday, April 02, 2020, 01:23 (1694 days ago) @ David Turell
It seems lots of different ancestors of different brain development were all living at the same times in Africa:
https://cosmosmagazine.com/palaeontology/more-clues-to-the-story-of-our-past?utm_source...
"In the first paper, in the journal Science Advances, researchers describe taking brain imprints of fossil skulls of the species Australopithecus afarensis (famous for “Lucy” and the “Dikika child’’) that shed new light on the evolution of brain growth and organisation.
***
"The results show that the brain of A. afarensis, which lived more than three million years ago, was organised like that of a chimpanzee but had prolonged brain growth like humans. That means it had a mosaic of ape and human features, a hallmark of evolution.
"The study also resolves a longstanding question of whether this species had a prolonged childhood, a period of time unique to humans that allows us to learn and grow.
"'As early as three million years ago, children had a long dependence on caregivers," says senior author Zeray Alemseged, who discovered Dikika in 2000 and now runs the Dikika Research Project in Ethiopia.
"'That gave children more time to acquire cognitive and social skills. By understanding that childhood emerged 3.5 million years ago, we are establishing the timing for the advent of this milestone event in human evolution."
"A. afarensis occupies a key position in the hominin family tree, as it is widely accepted to be ancestral to all later hominins, including the human lineage. Lucy and her kind walked upright, had brains that were around 20% larger than those of chimpanzees, and may have used sharp stone tools, Alemseged says.
***
"The Broken Hill (Kabwe 1) skull is one of the best-preserved fossils of the early human species Homo heidelbergensis and was previously thought to be about 500,000 years old – although dating it has been difficult due to its haphazard recovery and the site being completely destroyed by quarrying.
"Now radiometric dating carried out by Grün’s team and collaborators, including the Natural History Museum (NHM) in London, puts the skull at a relatively young 274,000 to 324,000 years old.
"The findings also suggest, the researchers say, that human evolution in Africa around 300,000 years ago was a much more complex process, with the co-existence of different human lineages.
***
“'But now it looks like the primitive species Homo naledi survived in southern Africa, H. heidelbergensis was in Central Africa, and early forms of our species existed in regions like Morocco and Ethiopia.”
"The third study, also published in Nature, collected and analysed genetic information from an 800,000-year-old fossilised tooth from the hominin Homo antecessor, revealing that this species was closely related to the last common ancestor of Homo sapiens, Neanderthals and Denisovans.
"And this, the authors say, implies that the modern-looking facial features seen in this species have deep roots in the ancestry of the genus Homo.
"This has been suggested before, but it has been a difficult issue to resolve because of the fragmentary nature of the fossil record and the failure to recover ancient DNA from Early and Middle Pleistocene hominins in Eurasia.
"In the new work, a team led by Frido Welker and Enrico Cappellini from the University of Copenhagen obtained sets of proteins from the dental enamel of molars of H. antecessor from Atapuerca, Spain, and Homo erectus from Dmanisi, Georgia.
"Phylogenetic analysis in collaboration with National Research Center on Human Evolution in Burgos, Spain, allowed them to propose that H. antecessor is a closely-related sister lineage to subsequent Middle and Late Pleistocene hominins such as modern humans.
"They suggest that the shape of the Neanderthal cranium represents a derived, rather than primitive, form."
Comment: the burst of human development in so many directions and types is sort of like the Cambrian Explosion. We can debate why this burst but it does not seem to be climate changes or oxygen levels, some of the obvious discussion points around the Cambrian. I say God's decision, but He won't tell us His reasoning. Now let us guess....nothing humanoid, please.
Human evolution; new anthropological info
DAVID: It seems lots of different ancestors of different brain development were all living at the same times in Africa:
https://cosmosmagazine.com/palaeontology/more-clues-to-the-story-of-our-past?utm_source...
DAVID: the burst of human development in so many directions and types is sort of like the Cambrian Explosion. We can debate why this burst but it does not seem to be climate changes or oxygen levels, some of the obvious discussion points around the Cambrian. I say God's decision, but He won't tell us His reasoning. Now let us guess....nothing humanoid, please.
Daft! You tell us that “We can only know his logic is like ours” and he probably has thought patterns etc. like ours, and then you ask for explanations that will not involve logic and thought patterns like ours! I will keep my theist’s hat on for the sake of argument, in which case of course it’s God’s decision. Why all the different forms of homo? Either he was experimenting, or he had set in motion a mechanism that enabled all organisms to work out their own ways of survival. And so once the human line had begun, it branched out as different sets of humanoids and homos found their own means of coping with the environment. How big their brains grew may have depended on the sort of activities they performed, since we know from the modern brain that it changes according to what tasks it is made to perform – though you would rather ignore this aspect of modern science since it conflicts with your theory that God has to preprogramme or dabble every variation. If you can’t find a logical explanation of your own but reject the logic of these two explanations because they don’t fit in with your image of God or your interpretation of his purpose, then please acknowledge the possibility that either your image of God or your interpretation of his purpose might be wrong.
Human evolution; new anthropological info
by David Turell , Thursday, April 02, 2020, 20:51 (1694 days ago) @ dhw
DAVID: It seems lots of different ancestors of different brain development were all living at the same times in Africa:
https://cosmosmagazine.com/palaeontology/more-clues-to-the-story-of-our-past?utm_source...DAVID: the burst of human development in so many directions and types is sort of like the Cambrian Explosion. We can debate why this burst but it does not seem to be climate changes or oxygen levels, some of the obvious discussion points around the Cambrian. I say God's decision, but He won't tell us His reasoning. Now let us guess....nothing humanoid, please.
dhw: Daft! You tell us that “We can only know his logic is like ours” and he probably has thought patterns etc. like ours, and then you ask for explanations that will not involve logic and thought patterns like ours! I will keep my theist’s hat on for the sake of argument, in which case of course it’s God’s decision. Why all the different forms of homo? Either he was experimenting, or he had set in motion a mechanism that enabled all organisms to work out their own ways of survival. And so once the human line had begun, it branched out as different sets of humanoids and homos found their own means of coping with the environment. How big their brains grew may have depended on the sort of activities they performed, since we know from the modern brain that it changes according to what tasks it is made to perform – though you would rather ignore this aspect of modern science since it conflicts with your theory that God has to preprogramme or dabble every variation. If you can’t find a logical explanation of your own but reject the logic of these two explanations because they don’t fit in with your image of God or your interpretation of his purpose, then please acknowledge the possibility that either your image of God or your interpretation of his purpose might be wrong.
Your possible human reasons As applied to God were exactly what I expected. As I've said, the more science we know about evolution and biochemistry, the more we may be able to see the probable logic behind what God has created. Try this possibility about my in-charge God: He set the evolution of Hominins and Homos in high drive just as in the Cambrian Explosion. It is of the same exact pattern, but a shortened time period. The experiences of many different homo types in many different environments with their sexual intermingling gave the final sapiens all the various immune and environmental tolerance abilities they would need to go forward in living successfully. I admit this does not have Him address every tiny issue, but as I look at the Cambrian with a burst of 50+ phyla settling down to the current much smaller number (35), the evolutionary patterns as used by God are the same, and therefore support the theory.
There are several more reports on this human explosion; sites if you want to read more but it repetitious:
https://nature.us17.list-manage.com/track/click?u=2c6057c528fdc6f73fa196d9d&id=c7ba...
https://www.newscientist.com/article/2239329-we-may-now-know-what-our-common-ancestor-w...
Human evolution; new anthropological erectus info
by David Turell , Thursday, April 02, 2020, 23:46 (1694 days ago) @ David Turell
Erectus is even older than previously thought:
https://cosmosmagazine.com/palaeontology/the-earliest-known-skull-of-homo-erectus?utm_s...
"The two-million-year-old fossil – believed to be of a child just two or three years old – was reconstructed from more than 150 fragments excavated over five years from the Drimolen cave system north of Johannesburg in South Africa.
"It suggests that Homo erectus existed 100,000 to 200,000 years earlier than previously thought.
"The researchers also uncovered the oldest known skull of the species Paranthropus, and their analysis reveals that in fact three hominin genera – Australopithecus being the third – were living as contemporaries in the area two million years ago.
"Combined with other evidence, this leads them to argue that the site reflects a period of transition in southern Africa driven by climatic variability, with endemic species such as Australopithecus going extinct, while new migrants – Homo and Paranthropus – moved in.
"According to La Trobe’s Andy Herries, who led the research, we can now say that Homo erectus shared the landscape with two other types of humans – a point that has been much debated.
“'This suggests that one of these other human species, Australopithecus sediba, may not have been the direct ancestor of Homo erectus, or us, as previously hypothesised,” he says."
Comment: Another new find that supports the idea of a hominin/homo evolutionary explosion
Human evolution; new anthropological erectus info
dhw: How can you possibly reject the argument that nobody can know whether the first artefacts were produced by an already enlarged brain, or their design and production were the cause of the brain’s enlargement?
DAVID: I will repeat, and it is an answer to your strange theory. The earlier tinier brain does not have the abstract thinking capacity to envision a new better artifact for the future.
And I repeat: please stop trying to gloss over the fact that the initial concept arises out of EXISTING information. That means the tiny brain comes up with the initial idea of throwing a weapon, but it does not have the capacity to design and then produce the artefact, which is why the brain has to increase its capacity.
DAVID: Please look at the following extremely long article, second half of which will give you different brain sizes at different evolutionary stages and how artifacts are considered.
https://paleontology.fandom.com/wiki/Human_evolution
Sorry, I’m not prepared to accept cookies, but in any case I know there are different brain sizes, and I know that new artefacts are found with new-sized brains. I’d be grateful if you would please pick out any passage for me which a) explains the expansion of the brain, and b) explains how anyone can know whether the FIRST artefacts associated with each expansion were conceived, designed and produced only AFTER the brain had ALREADY expanded, or were conceived BEFORE the brain expanded and were then designed and produced by means of expanding the brain.
DAVID: In this article please note the time it took for sapiens to learn how to use their newly enlarged brain. This alone totally refute your 'natural enlargement' theory. We are a species that arrived living/acting just like erectus. The real arrival of our current abstract conceptualization is all in the past eight thousand years since agriculture started.
We have dealt with this before! Once the brain is enlarged – no matter which species – it doesn’t HAVE to go on producing new things. You yourself pointed out that there were indigenous tribes who still live like their ancient ancestors, remember? There can be long periods of stasis in which nothing new occurs. This was the case with most of our antecedents. (I believe Erectus himself hung around for about 1.5 million years!) If there was a sudden burst of sapiens activity eight thousand years ago, that would be the equivalent of an earlier homo having the bright idea of throwing a weapon after there’s been a long period of stasis. Sapiens’ brain, however, did not expand – you reject my proposal that this was for anatomical reasons – and complexification took over and proved so efficient that the brain actually shrank. How on earth does all this “refute” my theory?
DAVID: I absolutely reject the idea that an earlier brain can think itself into a larger size, which is exactly what your theory gives us.
Do you absolutely reject the idea that the modern brain can think itself into complexification and into enlargement on a restricted scale? I note that you have reverted to materialism. As a dualist, do you absolutely reject the idea that the soul can influence the brain to the extent that it can change itself and even add connections?
DAVID: It is wishful thinking to get around the question of speciation among early homos, hoping it gets around God doing it. Your anticipated answer to keep you on the fence: God let the do it themselves is your way of staying agnostic. For us theists, it is God-lite, a poor excuse of a purposeful God who know full well what He is doing, as He made the universe, the perfect Earth and life quite efficiently all by Himself. This is a discussion between a theist and an agnostic. On that basis I feel God speciates.
That is no basis at all, and is a very poor reason for rejecting arguments that question the logic of your very personal view of God’s purposes and methods. It is also a poor reason for rejecting alternative views of a God whose purposes and methods and thoughts and reasons and nature and logic by your admission cannot be known. Do you honestly believe that every theist accepts your version of evolution and your explanation of brain expansion?
dhw: I describe a different theory than the theory you have faith in. Mine is extrapolated from known facts (the way the modern brain functions) and you apparently have no facts at all to support your own.
DAVID: Your theory ignores all the considerations I give you, all factual. The bold seems to indicate I don't know how to think about the facts I have presented.
The only fact you have presented is that new artefacts are found alongside new brains. This does not in any way contradict my theory, as I keep explaining, since it is the FIRST artefacts each time that would have driven the expansion. Now please tell me what logic and what facts support your theory that your God preprogrammed or dabbled each expansion BEFORE your dualist’s soul could come up with a new idea which did not require any new information?
Human evolution; new anthropological erectus info
by David Turell , Friday, April 03, 2020, 23:00 (1693 days ago) @ dhw
dhw: How can you possibly reject the argument that nobody can know whether the first artefacts were produced by an already enlarged brain, or their design and production were the cause of the brain’s enlargement?
DAVID: I will repeat, and it is an answer to your strange theory. The earlier tinier brain does not have the abstract thinking capacity to envision a new better artifact for the future.
dhw: And I repeat: please stop trying to gloss over the fact that the initial concept arises out of EXISTING information. That means the tiny brain comes up with the initial idea of throwing a weapon, but it does not have the capacity to design and then produce the artefact, which is why the brain has to increase its capacity.
Under your weird theory, the earlier homo wishes he had a bigger brain because he wants to throw something, better than a stone, needs to design it, but can't, and his wishes force the brain to grow in size?!!
DAVID: Please look at the following extremely long article, second half of which will give you different brain sizes at different evolutionary stages and how artifacts are considered.
https://paleontology.fandom.com/wiki/Human_evolutionSorry, I’m not prepared to accept cookies, but in any case I know there are different brain sizes, and I know that new artefacts are found with new-sized brains
I'll try elsewhere.
DAVID: I absolutely reject the idea that an earlier brain can think itself into a larger size, which is exactly what your theory gives us.
dhw: I note that you have reverted to materialism. As a dualist, do you absolutely reject the idea that the soul can influence the brain to the extent that it can change itself and even add connections?
Will you please ignore my short hand! The modern soul/brain complex only tells us about tiny enlargements
DAVID: It is wishful thinking to get around the question of speciation among early homos, hoping it gets around God doing it. Your anticipated answer to keep you on the fence: God let the do it themselves is your way of staying agnostic. For us theists, it is God-lite, a poor excuse of a purposeful God who know full well what He is doing, as He made the universe, the perfect Earth and life quite efficiently all by Himself. This is a discussion between a theist and an agnostic. On that basis I feel God speciates.dhw: That is no basis at all, and is a very poor reason for rejecting arguments that question the logic of your very personal view of God’s purposes and methods. It is also a poor reason for rejecting alternative views of a God whose purposes and methods and thoughts and reasons and nature and logic by your admission cannot be known. Do you honestly believe that every theist accepts your version of evolution and your explanation of brain expansion?
i have no idea, but the ID folks are with me.
dhw: I describe a different theory than the theory you have faith in. Mine is extrapolated from known facts (the way the modern brain functions) and you apparently have no facts at all to support your own.DAVID: Your theory ignores all the considerations I give you, all factual. The bold seems to indicate I don't know how to think about the facts I have presented.
dhw: The only fact you have presented is that new artefacts are found alongside new brains. This does not in any way contradict my theory, as I keep explaining, since it is the FIRST artefacts each time that would have driven the expansion. Now please tell me what logic and what facts support your theory that your God preprogrammed or dabbled each expansion BEFORE your dualist’s soul could come up with a new idea which did not require any new information?
Same weird tale: wishing for some new complex abstract design hard enough grows a bigger brain which then designs it!
Human evolution; new anthropological erectus info II
by David Turell , Friday, April 03, 2020, 23:31 (1693 days ago) @ David Turell
DAVID: Please look at the following extremely long article, second half of which will give you different brain sizes at different evolutionary stages and how artifacts are considered.
https://paleontology.fandom.com/wiki/Human_evolution
dhw: Sorry, I’m not prepared to accept cookies, but in any case I know there are different brain sizes, and I know that new artefacts are found with new-sized brains
I'll try here. I'm sorry cookies scare you. I use DuckDuckgo in browsing to avoid trouble.
"Using tools is not only a sign of intelligence, it also may have acted as a stimulus for human evolution. Over the past 3 or 2 million years, human brain size has increased threefold. A brain needs a lot of energy: the brain of modern man uses about 20 Watts (about 400 calories per day), one fifth of total human energy consumption.... However, plant food in general yields considerably less energy and nutritive value than meat. Therefore, being able to hunt for large animals, which was only possible by using tools such as spears, made it possible for humans to sustain larger and more complex brains, which in turn allowed them to develop yet more intelligent and efficient tools. (my bold)
"Precisely when early man started to use tools is difficult to determine, because the more primitive these tools are (for example, sharp-edged stones) the more difficult it is to decide whether they are natural objects or human artifacts. There is some evidence that the australopithecines (4 MYA) may have used broken bones as tools, but this is debated.
***
"Until about 50,000–40,000 years ago the use of stone tools seems to have progressed stepwise: each phase (habilis, ergaster, neanderthal) started at a higher level than the previous one, but once that phase had started further development was slow. In other words, one might call these Homo species culturally conservative. After 50,000 BP, what Jared Diamond, author of The Third Chimpanzee, and other anthropologists characterize as a Great Leap Forward, human culture apparently started to change at much greater speed: "modern" humans started to bury their dead carefully, made clothing out of hides, developed sophisticated hunting techniques (such as pitfall traps, or driving animals to fall off cliffs), and made cave paintings. This speed-up of cultural change seems connected with the arrival of modern humans, homo sapiens sapiens. Additionally, human culture began to become more advanced, in that, different populations of humans begin to create novelty in existing technologies. Artifacts such as fish hooks, buttons and bone needles begin to show signs of variation among different population of humans, something that has not been seen in human cultures prior to 50,000 BP. Typically, neanderthalenis populations are found with technology similar to other contemporary neanderthalensis populations. (my bold)
"Theoretically, modern human behaviour is taken to include four ingredient capabilities: abstract thinking (concepts free from specific examples), planning (taking steps to achieve a farther goal), innovation (finding new solutions), and symbolic behaviour (such as images, or rituals). Among concrete examples of modern human behaviour, anthropologists include specialization of tools, use of jewelry and images (such as cave drawings), organization of living space, rituals (for example, burials with grave gifts), specialized hunting techniques, exploration of less hospitable geographical areas, and barter trade networks. Debate continues whether there was indeed a "Revolution" leading to modern man ("the big bang of human consciousness"), or a more gradual evolution."
Comment: The bolded statements, especially the first, fit my approach, to which you now seem to agree, that bigger, better brains (remember souls at work) create the better artifacts. But then you strain credulity by imagining the earlier form absorbing current info thinks a new design might exist, and somehow grows a bigger, better brain to achieve the design. Dreaming a theory out of thin air. Note the authors use my approach: we had to learn to use our newly developed brain over the 315.000 +/- years it has existed. We were just like erectus at our start.
Human evolution; Lucy's brain and slow growth infants
by David Turell , Saturday, April 04, 2020, 00:23 (1693 days ago) @ David Turell
A recent study raises the issue of infant growth and dependence:
https://www.sciencedaily.com/releases/2020/04/200403092009.htm
Credit: © CrazyCloud / Adobe Stock
"A new study led by paleoanthropologists Philipp Gunz and Simon Neubauer from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, reveals that Lucy's species Australopithecus afarensis had an ape-like brain. However, the protracted brain growth suggests that -- as is the case in humans -- infants may have had a long dependence on caregivers.
"Contrary to previous claims, the endocranial imprints of Australopithecus afarensis reveal an ape-like brain organization, and no features derived towards humans. However, a comparison of infant and adult endocranial volumes nevertheless indicates more human-like protracted brain growth in Australopithecus afarensis, likely critical for the evolution of a long period of childhood learning in hominins.
"The brains of modern humans are not only much larger than those of our closest living ape relatives, they are also organized differently, and take longer to grow and mature. For example, compared with chimpanzees, modern human infants learn longer at the expense of being entirely dependent on parental care for longer periods of time. Together, these characteristics are important for human cognition and social behavior, but their evolutionary origins remain unclear. Brains do not fossilize, but as the brain grows and expands before and after birth, the tissues surrounding its outer layer leave an imprint in the bony braincase. Based on these endocasts the researchers could measure endocranial volume, and infer key aspects of brain organization from impressions of brain convolutions in the skull.
"A key difference between apes and humans involves the organization of the brain's parietal and occipital lobes...Hypothetically, such brain reorganization in australopiths could have been linked to behaviors that were more complex than those of their great ape relatives (e.g., tool manufacture, mentalizing, and vocal communication). Unfortunately, the lunate sulcus typically does not reproduce well on endocasts, so there is unresolved controversy about its position in australopiths.
***
"The pace of dental development of the Dikika infant was broadly comparable to that of chimpanzees and therefore faster than in modern humans. However, given that the brains of Australopithecus afarensis adults were roughly 20 percent larger than those of chimpanzees, the Dikika child's small endocranial volume suggests a prolonged period of brain development relative to chimpanzees. "Even a conservative comparison of the Dikika infant to small-statured and small-brained adults like Lucy, suggests that brain growth in Australopithecus afarensis was protracted as in humans today," explains Simon Neubauer."
Comment: It seems was that Lucy was certainly the start of a of a long road to sapiens.
Human evolution; Homo antecessor is a close cousin
by David Turell , Saturday, April 04, 2020, 00:33 (1693 days ago) @ David Turell
Another new review of a Homo fossil find:
https://www.sciencedaily.com/releases/2020/04/200401111657.htm
"Genetic information from an 800,000-year-old human fossil has been retrieved for the first time. The results from the University of Copenhagen shed light on one of the branching points in the human family tree, reaching much further back in time than previously possible.
"An important advancement in human evolution studies has been achieved after scientists retrieved the oldest human genetic data set from an 800,000-year-old tooth belonging to the hominin species Homo antecessor.
"'I am happy that the protein study provides evidence that the Homo antecessor species may be closely related to the last common ancestor of Homo sapiens, Neanderthals, and Denisovans. The features shared by Homo antecessor with these hominins clearly appeared much earlier than previously thought. Homo antecessor would therefore be a basal species of the emerging humanity formed by Neanderthals, Denisovans, and modern humans," adds José María Bermúdez de Castro, Scientific Co-director of the excavations in Atapuerca and co-corresponding author on the paper.
***
"'This study is an exciting milestone in palaeoproteomics. Using state of the art mass spectrometry, we determine the sequence of amino acids within protein remains from Homo antecessor dental enamel. We can then compare the ancient protein sequences we 'read' to those of other hominins, for example Neanderthals and Homo sapiens, to determine how they are genetically related," says Jesper Velgaard Olsen."
Comment: Still fits my idea that here was a Homo explosion like the Cambrian.
Human evolution; tool and brain advances correlated
by David Turell , Tuesday, April 07, 2020, 04:51 (1689 days ago) @ David Turell
edited by David Turell, Tuesday, April 07, 2020, 05:35
From over three mya till recently it was a stone tooled world:
https://www.britannica.com/science/human-evolution/Refinements-in-tool-design
"In Africa the Early Paleolithic (3.3–0.2 mya) comprises several industries. The first tools (hammers, anvils, and primitive cutting tools) made way for the earliest human-made chipped flake tools and core choppers (2.5–2.1 mya). Double-faced hand axes, cleavers, and picks (collectively known as bifaces) appeared about 1.5 mya and persisted until about 200 kya. Archaeologists have detected some improvements of technique and product during the half-million-year span of core-flake industries. Although the major biface industry—the Acheulean—has been characterized as basically static, it too shows evidence of refinement over time, finally resulting in elegant, symmetrical hand axes that required notable skill to make.
***
"El ʿUbeidīya, Israel, provides evidence that people and bifaces had spread out of Africa by 1.4 mya. In Europe, Acheulean tools appear 500 kya and persist until about 250–150 kya; they also occur in South Asia. Sites in China (800 kya), Korea, and Japan contain bifaces, but they differ from Acheulean tools. No such technology has been found in tropical Southeast Asia, where bamboo tools may have sufficed.
"In both Africa and Eurasia the Middle Paleolithic was long thought to have lasted from about 200 kya to as recently as 30 kya, depending upon location. While tools from the Early Paleolithic slowly changed across space and time, the Middle Paleolithic was characterized by an explosion of local and regional variations in size and shape and by frequencies of reshaped flakes, blades, scrapers, hand axes, and other tools. Projectile points began to be emphasized in some regions, with bone being used as well as stone; bone arrow points dating to more than 60,000 years ago have been found at Sibudu Cave in South Africa.
"Although they vary across time and space, Middle Paleolithic tools as a whole are characterized by carefully prepared cores from which elegant flakes or blades were struck. Notably, tools of this type have been found at the Gademotta site in Ethiopia’s Rift Valley in stratigraphic levels that date to approximately 275 kya. Additional blades dating to roughly 315 kya have been found at Morocco’s Jebel Irhoud site. (me: the first H. sapiens)
"Late Paleolithic industries dating to 50–10 kya comprise diverse blade and microblade tools, especially in Europe. Late Paleolithic peoples used a variety of materials for their tools and bodily ornaments, including bone, stone, wood, antler, ivory, and shell. Stone blades were long, thin, and very effective cutting tools. Often, when they became dull, someone retouched them via pressure flaking, which requires fine motor control and coordination.
Microblades and other points were probably hafted to produce throwing and stabbing spears. Other composite tools of the period include atlatls, harpoons, fish weirs, and bows and arrows. Late Paleolithic people also developed techniques for grinding and polishing, with which they made beads, pendants, and other artistic objects. They also made needles (perhaps for sewing fitted clothing), fish hooks, and fish gorges.
"Yet if the stunning proliferation and stylistic variability of tools, bodily ornaments, and artistic works during the Paleolithic do not point unequivocally to the specific use of speech, the presence of these symbolically mediated artifacts—among the earliest of which are shell beads found in Morocco and made about 82,000 years ago—does indicate that early humans were capable of complex conceptual and abstract thought.
***
"Although versatile human speech is reasonably linked to a relatively spacious pharynx and mobile tongue, the absence of such features is not a compelling reason to deny some form of vocal language in ancestral hominins. It is argued that articulate human speech is impossible without a lowered voice box (larynx) and an expanded region above it. If this presumption were true, even Neanderthals would be inept vocally and probably also quite primitive cognitively as compared with Late Paleolithic H. sapiens populations such as the Cro-Magnons.
"...one cannot expect the problem of language origins or language competence to be clarified by studying Paleolithic symbolism and imagery, despite the awesome array of cave art and polished bone, antler, ivory, stone, and shell artifacts associated with the period. Yet if the stunning proliferation and stylistic variability of tools, bodily ornaments, and artistic works during the Paleolithic do not point unequivocally to the specific use of speech, the presence of these symbolically mediated artifacts—among the earliest of which are shell beads found in Morocco and made about 82,000 years ago—does indicate that early humans were capable of complex conceptual and abstract thought.
Comment: This picture dating back over three million years is one of several large jumps in brain size while it was still just stone tools with varying refinements until sapiens learned to really use their brain, resulting in ornaments, art and symbolically burying the dead appearing. For more on speech see my previous quotes here from "The Ape That Spoke", by McCrone. There is no evidence from this presentation that dhw's theory that a drive for abstract design forced brain enlargement. Lots of new sized brains but not much advancement
Human evolution; Chomsky Everett language fight
by David Turell , Saturday, April 18, 2020, 20:29 (1678 days ago) @ David Turell
Everett's finding of no recursion in the Piraha language set the battle which still rages. I've read Wolfe's book critical of Chomsky, which allows me to critically present this essay:
https://aeon.co/essays/why-language-is-not-everything-that-noam-chomsky-said-it-is?utm_...
"While that debate rages, however, its focal point has come to be how much, if any, of human grammar is innate.
"That is where my work comes in. In 2005, I published a paper in the journal Current Anthropology, arguing that Pirahã – an Amazonian language unrelated to any living language – lacked several kinds of words and grammatical constructions that many researchers would have expected to find in all languages. I made it clear that this absence was not due to any inherent cognitive limitation on the part of its speakers, but due to cultural values, one in particular that I termed the ‘immediacy of experience principle’.
***
"For advocates of universal grammar the arguments here present a challenge – defending an autonomous linguistic module that can be affected in many of its core components by the culture in which it ‘grows’. If the form or absence of things such as recursion, sound structure, word structure, quantification, numerals, number, and so on is tightly constrained by a specific culture, as I have argued, then the case for an autonomous, biologically determined module of language is seriously weakened. (my bold)
***
"Although Chomsky refers to ‘language’ in his writings, he means exclusively a recursive grammatical system. Thus, his claim that ‘language’ derives from a narrow faculty of language that is populated only by recursion is a circular claim, because he is simply telling us how he has defined language for years. If there were a language that chose not to use recursion, it would at the very least be curious and at most would mean that Chomsky’s entire conception of language/grammar is wrong.
***
"Recursion is common in English and many other languages. For example, put the noun ‘truck’ and the noun ‘driver’ inside a single noun, and you get ‘truck-driver’. Put a sentence inside another sentence and you get ‘John said that he did not do it,’ where ‘he did not do it’ is a sentence inside the larger sentence,
***
"Like anyone, I could be wrong. Pirahã might one day be proven to have recursion. But no one has done anything remotely close to that yet, and none have successfully rebutted my 2005 analysis. There was a critical discussion of my work in the journal Language, as I mention directly, where I and my critics went back and forth, but it is fair to say that neither side was more convinced after the exchange than before. Some of the reviews and discussions of Wolfe’s book have even remarked that the debate is irrelevant. That is also wrong. The debate is crucial to our understanding of human language and evolution, and so far the evidence supports my view, not Chomsky’s.
***
"Pirahãs who speak Pirahã natively and are culturally Pirahãs speak very little Portuguese, if any. And, according to Sakel’s work, when they do speak it is non-recursive Portuguese. This is a (fascinating) fact about the contact between Pirahã and Portuguese cultures and the basic values of the Pirahãs. It is not a question of intelligence. They are not stupid or backwards or genetically isolated weirdos. It is the connection between their culture and grammar that brings this about.
***
"The Chomskyan view is that Pirahã is not only not a counterexample, but an (irrelevant) exception. The new Chomskyan view that ‘recursion is just a state of mind’ won’t make Pirahã irrelevant. Thinking recursively is not the same as having a recursive grammar.
***
"Recursion is not the biological basis for language. It is an enhancement of human thought.
(my bold) [This make the best sense to me.]
***
"In short, the question is not whether humans can think recursively. The question is whether this ability is linked specifically to language or instead to human cognitive accomplishments more generally (it could be connected to both, but that is less likely given what we know about the organisation of the brain).
***
"If I am correct, then I have shown that the sentential grammars of human languages don’t need to be constructed recursively. People might all think recursively but lack recursion in their grammars. What I have shown is that for the very reason that the Pirahãs can think recursively, then if their language lacks recursion, recursion is not fundamental to human language but is rather a component of human cognition more generally. (my bold)
***
"Recursion is not the basis of human language. One language shows that. Language does not seem to be innate. There seems to be no narrow faculty of language nor any universal grammar. Language is ancient and emerges from general human intelligence, the need to build communities and cultures."
Comment: The last bold settles a tempest in a teapot. Chomsky cannot tolerate being challenged. Our language ability is simply an amazing singular human attribute, in which recursion facilitates thought.
Human evolution; Chomsky Everett language fight
QUOTE: "Recursion is not the basis of human language. One language shows that. Language does not seem to be innate. There seems to be no narrow faculty of language nor any universal grammar. Language is ancient and emerges from general human intelligence, the need to build communities and cultures."
For what it’s worth, I am 100% in agreement with this. Of course many languages have influenced one another, but I would suggest that all the original languages were the result of the universal need for communication, which led to different communities producing their own sets of sounds to meet with their needs.
Human evolution; Chomsky Everett language fight
by David Turell , Sunday, April 19, 2020, 20:24 (1677 days ago) @ dhw
QUOTE: "Recursion is not the basis of human language. One language shows that. Language does not seem to be innate. There seems to be no narrow faculty of language nor any universal grammar. Language is ancient and emerges from general human intelligence, the need to build communities and cultures."
dhw: For what it’s worth, I am 100% in agreement with this. Of course many languages have influenced one another, but I would suggest that all the original languages were the result of the universal need for communication, which led to different communities producing their own sets of sounds to meet with their needs.
I fully agree. I find the fight interesting.
Human evolution; possible recursion in monkeys
by David Turell , Saturday, June 27, 2020, 19:19 (1608 days ago) @ David Turell
Not at all proven, but presented as part of the effort to make humans less different than they are. The so-called recursions are symbols monkeys are taught by habit to select and repeat, without the meanings we appreciate in speech in most languages:
https://www.sciencenews.org/article/monkeys-may-share-key-grammar-related-skill-with-hu...
"In lab experiments, monkeys demonstrated an ability akin to embedding phrases within other phrases, scientists report June 26 in Science Advances. Many linguists regard this skill, known as recursion, as fundamental to grammar (SN: 12/4/05) and thus peculiar to people.
"But “this work shows that the capacity to represent recursive sequences is present in an animal that will never learn language,” says Stephen Ferrigno, a Harvard University psychologist.
"Recursion allows one to elaborate a sentence such as “This pandemic is awful” into “This pandemic, which has put so many people out of work, is awful, not to mention a health risk.”
***
"Three rhesus monkeys lacked humans’ ease on the task. But after receiving extra training, two of those monkeys displayed recursive learning, Ferrigno’s group says. One of the two animals ended up, on average, more likely to form novel recursive sequences than about three-quarters of the preschoolers and roughly half of the Bolivian villagers.
***
"Study participants were trained to arrange two sets of symbols in recursive patterns. Each training set consisted of four brackets — say, { } [ ] — with each bracket shown at random spots on a computer screen or on cards placed on a table. The goal was to learn to touch the four brackets in a recursive sequence with pairs of related forms in the center and on the ends, such as { [] }. Chimes for humans and food rewards for monkeys indicated when an individual had touched a recursive sequence.
"The researchers then tested whether humans and monkeys, without further training, would arrange new bracket sets, such as ()[], in a recursive pattern, say, ( [] ).
***
"Scientists familiar with the study find it fascinating but remain unconvinced that participants needed to understand recursion to learn the bracket sequences.
"Unlike recursive phrases in languages, which are meaningfully related to each other, pairs of inner and outer brackets in the task are arbitrary symbols, say cognitive scientists Claudia Männel and Emiliano Zaccarella, both of the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, Germany. Participants might have correctly sequenced novel brackets without thinking about recursion, Männel and Zaccarella suggest. Perhaps subjects arranged items in a symmetric, visually pleasing way consistent with what they remembered from earlier trials.
***
"Monkeys, which generally can’t mentally keep track of as many pieces of information as people can, would struggle more than people to recall bracket orders, consistent with the animals’ poorer performance on the task, Dehaene argues.
"Everyone agrees on one thing — deciphering what makes human language special still presents a major scientific challenge."
Comment: the bold above is ridiculous example of the thought pattern behind the research. Of course we are wildly/widely different. True recursion requires complex thinking.
Human evolution; Egnor on Chomsky
by David Turell , Thursday, August 06, 2020, 01:08 (1568 days ago) @ David Turell
Very high praise:
https://mindmatters.ai/2020/08/why-linguist-noam-chomsky-is-a-great-scientist-of-our-er...
"...his theory of linguistics is brilliant and represents an anthropological, biological, and even metaphysical insight unrivaled in science since relativity and quantum mechanics. A case can be made that Chomsky’s insights are more profound than even those of modern physics, because they plumb the human soul in ways that physics cannot.
***
"The evolutionary question remains unanswered, except that we now know that human language is a recent acquisition—there is good evidence that it arose no earlier than 50,000 and 100,000 years ago, which is very recent in the evolutionary time frame. There is also evidence that it arose abruptly, without any precursor. Suddenly man had language.
***
"Language has semantics and syntax. While meanings of words (semantics) does seem to be acquired by a system of trial and reward, syntax (grammar and word order) does not arise this way.
***
"Unlike the abundant evidence for trial and error acquisition of semantics in infancy (a baby in an English-speaking family learns to say “cat” when pointing at the house pet), there is not the slightest evidence for “trial and error” syntax acquisition in infancy. Very young children use correct grammar (syntax) from the very beginning of language development. This intrinsic knowledge of grammar happens for all languages, without exception.
"Aside from the utter lack of evidence for a process of trial and error in studies of infant language, Chomsky observed that an infant could not really have the experience needed to explain syntax acquisition that way. Even young children inherently know and use grammar rules. They construct and understand sentences of such consistency, intricacy, and complexity that it is clear that they could not have acquired this knowledge merely through incidental daily experience with language.
"There is no behavioral explanation for the acquisition of grammar. Kids don’t start out with completely random jumbles of words and gradually, by a system of rewards, learn subject and verb predicates. Even very young children come fully equipped with an instinctive knowledge of grammar that is common to all languages—a “language” organ—as Chomsky called it. They learn the meaning of words with use but they instinctively know grammar from birth. (my bold)
***
"Syntax and semantics don’t overlap and therefore an infant cannot learn syntax via linkage to the semantic content of words. Meaning can be acquired via the behaviorist paradigm but grammar cannot. Grammar has a structure and internal logic that is not learned by young children—toddlers don’t study sentence structure and it is far too profound and complex to be acquired as a spandrel by just listening to the spoken language of others. Human beings, alone among animals, know correct grammar from birth, before they have spoken or heard a single word.
***
"Chomsky’s insight that language is an in-born “organ” unique to humans is of obvious relevance to our understanding of human exceptionalism. Chomsky showed that no animal has language of any sort and that human language did not evolve from animal behavior and is not acquired by a behavioral system of rewards and punishments. This is not to say that non-human animals do not link meanings to sounds—they certainly do—but animals do not structure their sounds and gestures syntactically. Animals have no grammar, and grammar is the hallmark of language.
"In Wilhelm von Humboldt’s famous insight, grammar is what enables language to “[make] infinite use of finite means.” By that, he means that we can generate an infinite number of sentences—and express an infinite number of ideas—from a finite number of grammatical rules. This echoes Aristotle’s beautiful aphorism on the soul—that “the soul is, in a way, all things.” Only humans are born with a language organ, whatever material (or immaterial) form it takes and this organ distinguishes us fundamentally from animals."
Comment: this inborn ability in our brain did not arise naturally. Note the bold. It had to be designed into the functionality of the brain that embryologically appears in young children. What is left out to fit Neil's posting limits is Chomsky's nonsense sentences that make sense and ones that don't, to prove his theory. Please read the discussion about them. Fabulous brilliance!! Here is a proper syntax nonsense sentence: "colorless green ideas sleep furiously." Here is an improper one: "furiously sleep ideas green colorless."
Human evolution; Egnor on Chomsky
QUOTE: “Even young children inherently know and use grammar rules. They construct and understand sentences of such consistency, intricacy, and complexity that it is clear that they could not have acquired this knowledge merely through incidental daily experience with language.”
We have had this discussion before, and the above typifies assumptions which in my personal experience as a parent, a grandparent, and a longtime lecturer on English grammar, have no basis in fact. Firstly, how young is “young”? In my experience, children start out with individual words, and gradually they learn to string them together. It is NOT clear that this knowledge is acquired through anything other than daily experience with language. An English/French/German child will copy structures used by its English/French/German parents and other acquaintances. These national structures often have totally different "rules", and how else could the child possibly learn those of its own language without being exposed to them? So NON-universal is grammar that once the child has mastered its own native grammar, it will become increasingly difficult to learn foreign equivalents. (That is why one should start teaching foreign languages as early as possible, to avoid “interference”.)
QUOTE: "There is no behavioral explanation for the acquisition of grammar. Kids don’t start out with completely random jumbles of words and gradually, by a system of rewards, learn subject and verb predicates. Even very young children come fully equipped with an instinctive knowledge of grammar that is common to all languages—a “language” organ—as Chomsky called it. They learn the meaning of words with use but they instinctively know grammar from birth. (David’s bold)
Has anyone managed to find out which grammatical structures a newborn baby is able to use? In my experience, as soon as kids can formulate different sounds, they do start out with a jumble of words (usually nouns), grammatical structures come later, and all kinds of grammatical “mistakes” can creep in and will in fact remain if the child’s parents and circle of acquaintances make the same mistakes. This is because young children learn by COPYING. They do not pop out of the womb and say to Mummy and Daddy, “You should say ‘I don’t understand’, not ‘me no understand’.” In fact I truly believe that when they pop out of the womb, they don’t say anything except WAAAAAH! because they haven’t yet LEARNED to say anything else, whether nouns, adjectives, verbs, adverbs, prepositions, articles, or intricate syntactical combinations of any or all of these.
QUOTE: “This is not to say that non-human animals do not link meanings to sounds—they certainly do—but animals do not structure their sounds and gestures syntactically. Animals have no grammar, and grammar is the hallmark of language.”
If you define language as human language, then no one can possibly disagree that animal language is not human language. Initially, all language consisted of sounds, gestures, chemical exchanges. Human language became largely based on sounds. We know that animals also communicate by sound, and zoologists have had no difficulty distinguishing the different meanings of different sounds. But for the most part, our fellow animals have a limited range of sounds, and their ways of life only require a limited range of meanings. Humans developed a vast range of activities which progressively required a wider and wider variety of sounds to convey a wider and wider variety of meanings. (I would argue that the requirements resulted in anatomical changes, but the development of the mechanics is a different subject.) My point is that human language has developed from animal language, mainly sound, and that grammar is only an extension of the need for ever more complex forms of expression as required by ever more complex forms of behaviour and an ever widening range of observation, experience, discovery etc. encompassing past, present and future, concrete and abstract, known and unknown. I strongly doubt that our earliest ancestors were born with a knowledge of grammar, because I strongly doubt whether grammar even existed. I suggest that it has evolved in response to new requirements, and it evolved in different ways as sapiens spread all over the planet in different groups, many with similar requirements but finding different sounds and ultimately different structures to meet those requirements. Language is one feature of the evolutionary process from the simple to the complex. What is the hallmark of human language? I’d say its almost infinite range of expression (initially confined mainly to sounds), to which grammar is an integral but probably late addition.
Human evolution; Egnor on Chomsky
by David Turell , Thursday, August 06, 2020, 18:38 (1568 days ago) @ dhw
dhw: QUOTE: “Even young children inherently know and use grammar rules. They construct and understand sentences of such consistency, intricacy, and complexity that it is clear that they could not have acquired this knowledge merely through incidental daily experience with language.”
We have had this discussion before, and the above typifies assumptions which in my personal experience as a parent, a grandparent, and a longtime lecturer on English grammar, have no basis in fact. Firstly, how young is “young”? In my experience, children start out with individual words, and gradually they learn to string them together. It is NOT clear that this knowledge is acquired through anything other than daily experience with language. An English/French/German child will copy structures used by its English/French/German parents and other acquaintances. These national structures often have totally different "rules", and how else could the child possibly learn those of its own language without being exposed to them? So NON-universal is grammar that once the child has mastered its own native grammar, it will become increasingly difficult to learn foreign equivalents. (That is why one should start teaching foreign languages as early as possible, to avoid “interference”.)
QUOTE: "There is no behavioral explanation for the acquisition of grammar. Kids don’t start out with completely random jumbles of words and gradually, by a system of rewards, learn subject and verb predicates. Even very young children come fully equipped with an instinctive knowledge of grammar that is common to all languages—a “language” organ—as Chomsky called it. They learn the meaning of words with use but they instinctively know grammar from birth. (David’s bold)
Has anyone managed to find out which grammatical structures a newborn baby is able to use? In my experience, as soon as kids can formulate different sounds, they do start out with a jumble of words (usually nouns), grammatical structures come later, and all kinds of grammatical “mistakes” can creep in and will in fact remain if the child’s parents and circle of acquaintances make the same mistakes. This is because young children learn by COPYING. They do not pop out of the womb and say to Mummy and Daddy, “You should say ‘I don’t understand’, not ‘me no understand’.” In fact I truly believe that when they pop out of the womb, they don’t say anything except WAAAAAH! because they haven’t yet LEARNED to say anything else, whether nouns, adjectives, verbs, adverbs, prepositions, articles, or intricate syntactical combinations of any or all of these.
QUOTE: “This is not to say that non-human animals do not link meanings to sounds—they certainly do—but animals do not structure their sounds and gestures syntactically. Animals have no grammar, and grammar is the hallmark of language.”
If you define language as human language, then no one can possible disagree that animal language is not human language. Initially, all language consisted of sounds, gestures, chemical exchanges. Human language became largely based on sounds. We know that animals also communicate by sound, and zoologists have had no difficulty distinguishing the different meanings of different sounds. But for the most part, our fellow animals have a limited range of sounds, and their ways of life only require a limited range of meanings. Humans developed a vast range of activities which progressively required a wider and wider variety of sounds to convey a wider and wider variety of meanings. (I would argue that the requirements resulted in anatomical changes, but the development of the mechanics is a different subject.) My point is that human language has developed from animal language, mainly sound, and that grammar is only an extension of the need for ever more complex forms of expression as required by ever more complex forms of behaviour and an ever widening range of observation, experience, discovery etc. encompassing past, present and future, concrete and abstract, known and unknown. I strongly doubt that our earliest ancestors were born with a knowledge of grammar, because I strongly doubt whether grammar even existed. I suggest that it has evolved in response to new requirements, and it evolved in different ways as sapiens spread all over the planet in different groups, many with similar requirements but finding different sounds and ultimately different structures to meet those requirements. Language is one feature of the evolutionary process from the simple to the complex. What is the hallmark of human language? I’d say its almost infinite range of expression (initially confined mainly to sounds), to which grammar is an integral but probably late addition.
I appreciate your lengthy input as a parent, writer, translator, multiple linguist, etc. Chomsky is widely accepted by most linguists, so you are an exception. I have no knowledge here accept the knowledge of the recursion argument which is perhaps partially settled.
Human evolution; more evidence of interbreeding
by David Turell , Thursday, August 06, 2020, 19:54 (1568 days ago) @ David Turell
Another unknown species appears in new DNA study:
https://phys.org/news/2020-08-dna-ancient-unidentified-ancestor-humans.html
"A new analysis of ancient genomes suggests that different branches of the human family tree interbred multiple times, and that some humans carry DNA from an archaic, unknown ancestor. Melissa Hubisz and Amy Williams of Cornell University and Adam Siepel of Cold Spring Harbor Laboratory report these findings in a study published 6th August in PLOS Genetics.
"In the new paper, the researchers developed an algorithm for analyzing genomes that can identify segments of DNA that came from other species, even if that gene flow occurred thousands of years ago and came from an unknown source. They used the algorithm to look at genomes from two Neanderthals, a Denisovan and two African humans. The researchers found evidence that 3 percent of the Neanderthal genome came from ancient humans, and estimate that the interbreeding occurred between 200,000 and 300,000 years ago. Furthermore, 1 percent of the Denisovan genome likely came from an unknown and more distant relative, possibly Homo erectus, and about 15% of these "super-archaic" regions may have been passed down to modern humans who are alive today.
"The new findings confirm previously reported cases of gene flow between ancient humans and their relatives, and also point to new instances of interbreeding. Given the number of these events, the researchers say that genetic exchange was likely whenever two groups overlapped in time and space. Their new algorithm solves the challenging problem of identifying tiny remnants of gene flow that occurred hundreds of thousands of years ago, when only a handful of ancient genomes are available."
Comment: based on current humans sexual activity is always possible. Each group contributed something useful to our DNA
Human evolution; language development sans instinct
by David Turell , Saturday, August 22, 2020, 18:27 (1552 days ago) @ David Turell
A totally different view completely opposing Chomsky:
https://aeon.co/essays/the-evidence-is-in-there-is-no-language-instinct?utm_source=Aeon...
"In the 1960s, the US linguist and philosopher Noam Chomsky offered what looked like a solution. He argued that children don’t in fact learn their mother tongue – or at least, not right down to the grammatical building blocks (the whole process was far too quick and painless for that). He concluded that they must be born with a rudimentary body of grammatical knowledge – a ‘Universal Grammar’ – written into the human DNA.
***
"It’s brilliant. Chomsky’s idea dominated the science of language for four decades. And yet it turns out to be a myth. A welter of new evidence has emerged over the past few years, demonstrating that Chomsky is plain wrong.
***
"The general lesson from these unfortunate individuals is that, without exposure to a normal human milieu, a child just won’t pick up a language at all. Spiders don’t need exposure to webs in order to spin them, but human infants need to hear a lot of language before they can speak. However you cut it, language is not an instinct in the way that spiderweb-spinning most definitely is.
***
"And In 2005, the US linguist-anthropologist Daniel Everett has claimed that Pirahã – a language indigenous to the Amazonian rainforest – does not use recursion at all. This would be very strange indeed if grammar really was hard-wired into the human brain.
***
"...children appear to pick up their grammar in quite a piecemeal way. For instance, focusing on the use of the English article system, for a long time they will apply a particular article (eg, the) only to those nouns to which they have heard it applied before. It is only later that children expand upon what they’ve heard, gradually applying articles to a wider set of nouns.
***
"We seem to construct our language by spotting patterns in the linguistic behaviour we encounter, not by applying built-in rules. Over time, children slowly figure out how to apply the various categories they encounter. So while language acquisition might be uncannily quick, there isn’t much that’s automatic about it: it arises from a painstaking process of trial and error. (my bold)
***
"...cognitive neuroscience research from the past two decades or so has begun to lift the veil on where language is processed in the brain. The short answer is that it is everywhere. Once upon a time, a region known as Broca’s area was believed to be the brain’s language centre. We now know that it doesn’t exclusively deal with language – it’s involved in a raft of other, non-linguistic motor behaviours.
***
"And indeed, we now believe that several of Chomsky’s evolutionary assumptions were incorrect. Recent reconstructions of the Neanderthal vocal tract show that Neanderthals probably did, in fact, have some speech capacity, perhaps very modern in quality. It is also becoming clear that, far from the dumb brutes of popular myth, they had a sophisticated material culture – including the ability to create cave engravings and produce sophisticated stone tools – not dissimilar to aspects of the human cultural explosion of 50,000 years ago. It is hard to see how they could have managed the complex learning and co-operation required for that if they didn’t have language... it now looks like early Homo sapiens and Homo neanderthalensis could have co-habited and interbred. It does not seem farfetched to speculate that they might also have communicated with one another. (my bold)
***
"...we don’t have to assume a special language instinct; we just need to look at the sorts of changes that made us who we are, the changes that paved the way for speech. This allows us to picture the emergence of language as a gradual process from many overlapping tendencies. It might have begun as a sophisticated gestural system, for example, only later progressing to its vocal manifestations. But surely the most profound spur on the road to speech would have been the development of our instinct for co‑operation.
***
"Children have far more sophisticated learning capacities than Chomsky foresaw. They are able to deploy sophisticated intention-recognition abilities from a young age, perhaps as early as nine months old, in order to begin to figure out the communicative purposes of the adults around them."
Comment: An enormous article from which I've presented cogent points. We were given the physical attributes to develop language without instinct.
Human evolution; Chomsky Everett language fight
by David Turell , Thursday, September 10, 2020, 18:22 (1533 days ago) @ David Turell
A different take from another linguist:
http://nautil.us/issue/89/the-dark-side/-talking-is-throwing-fictional-worlds-at-one-an...
"Adger’s knowledge of human languages runs deep. For decades he has ventured beyond the classroom to study languages in Kenya, India, the Himalayas, and the Scottish Highlands. In the linguistic world where a debate still sizzles over whether the world’s languages are generated by individual cultures or built on a similar foundation, Adger stands firmly on the latter side. Languages do not vary randomly, he says. “They have a design, a structure, a pattern, in common.” Despite that seeming constraint, Adger argues in his new book, Language Unlimited, that the sentences we make are infinite in faculty, form, and expression. Language “is the engine of imagination,” he writes.
***
"I asked him to crystallize the argument of his new book for me, and he didn’t hesitate. “It’s an argument about our creative use of language,” he said. “We have a specialized kind of mental technology that neither animals nor computers have. That’s the capacity to combine individual bits of language, and then out of that build larger meanings.”
***
"humans can combine these into highly complex structures that carry new meanings. That doesn’t seem to happen with animals.
"Now, apes and chimpanzees and bonobos are really bright. They’re amazing creatures. But bonobos don’t do syntax. If you look carefully at the way that they respond to us trying to teach them language, they’re using their general intelligence to figure out what they think we might want, or what we might be trying to say to them. Our language locks the meanings into place by the way that the things are combined together. We can’t make animals do this. It would be like trying to teach humans to do bee dances.
***
"I want to say, “No, look at the amazing complexity of languages around the world, and look at how unified it all is.” I wanted to take people’s minds away from this notion of grammar as something dry and boring, and something that people get told at school, and convey this fact that combining words into sentences is a wonder. It’s a marvelous aspect of our human universe. It takes us as finite beings and gives us almost infinite capacity to create new worlds of imagination.
***
"The really core human thing is the creation of hierarchical sentence structures called “Merge.” And what’s interesting about Merge is it doesn’t do much apart from create these hierarchies for you and link them to word orders and meanings. If you think about a sentence in a language, we don’t really think much about what we’re saying, they just come out, and hopefully convey what we mean. However, if you begin to look carefully at sentences, what you find is that they are organized in this hierarchy.
***
"You find that same pattern—things that get attached to the verb—in language after language.
That tells me there’s some underlying deep structure to how human language organizes sentences.
***
"Our general cognitive abilities have a subset of concepts. And some subsets are available to human languages and some are not. No one understands why. It’s a total mystery. But it speaks to this universality of the idea that, in a sense, there’s one human language.
***
"According to Dan [Everett], I think, Pirahã has a hierarchical structure. It’s just that he thinks the hierarchal structure is flat, and therefore Pirahã doesn’t make use of this massive recursive device. But it does. It builds up flat, small structures. As far as I understand, recent work on Pirahã shows that you have this ability to stack noun phrases at the start of the sentence to mark them as the topic of the conversation. So I think Pirahã just looks like another language. It has all of the normal properties that languages have. It just likes flat structures, apparently."
Comment: He is with Chomsky and feels Everett is wrong. He supports the idea we are born with a basic language mechanism.
Human evolution; Chomsky Everett language fight
QUOTES: "You find that same pattern—things that get attached to the verb—in language after language. That tells me there’s some underlying deep structure to how human language organizes sentences."
"Our general cognitive abilities have a subset of concepts. And some subsets are available to human languages and some are not. No one understands why. It’s a total mystery. But it speaks to this universality of the idea that, in a sense, there’s one human language."
DAVID: He is with Chomsky and feels Everett is wrong. He supports the idea we are born with a basic language mechanism.
We all know that animals don’t speak any human language, and human language is a wonderfully versatile instrument, and it is no surprise to find that all human languages attempt to convey concepts – and why not add perceptions and instructions and emotions and so on? Nevertheless, it should be pointed out that our fellow animals also use sounds to convey meanings, and so one should be wary of confining the word “language” to human language. And yes, we all know that we are born with a basic language mechanism because surprise, surprise, all humans speak a language. Neither animals nor humans would be able to speak if they didn’t have mechanisms for communication and for formulating whatever they want to communicate. But of course I agree that animal languages are different from human languages in so far as ours are infinitely more complex. As far as I know, humans tend to speak the language that is spoken in their particular part of the world. I have never yet heard a newborn baby speak any human language at all, and when the toddler does start to speak, I have never heard him or her speak anything but what he or she has learned from his or her immediate surroundings. And if our author has studied languages in different parts of the world, he will know that the sounds, the vocabulary and the grammar differ from one language to another. And so while it is true that as far as we know, all languages have some form of grammar, and they all use words to which we have given various classifications - also using words - and they all use ways of linking words together, there is no such thing as a universal grammar, let alone one that is inborn, and this speaks to the “universality of the idea that, in a sense”, there are thousands of human languages. This discussion is one long quibble over terminology.
Human evolution; Chomsky Everett language fight
by David Turell , Friday, September 11, 2020, 21:09 (1532 days ago) @ dhw
QUOTES: "You find that same pattern—things that get attached to the verb—in language after language. That tells me there’s some underlying deep structure to how human language organizes sentences."
"Our general cognitive abilities have a subset of concepts. And some subsets are available to human languages and some are not. No one understands why. It’s a total mystery. But it speaks to this universality of the idea that, in a sense, there’s one human language."
DAVID: He is with Chomsky and feels Everett is wrong. He supports the idea we are born with a basic language mechanism.
dhw: We all know that animals don’t speak any human language, and human language is a wonderfully versatile instrument, and it is no surprise to find that all human languages attempt to convey concepts – and why not add perceptions and instructions and emotions and so on? Nevertheless, it should be pointed out that our fellow animals also use sounds to convey meanings, and so one should be wary of confining the word “language” to human language. And yes, we all know that we are born with a basic language mechanism because surprise, surprise, all humans speak a language. Neither animals nor humans would be able to speak if they didn’t have mechanisms for communication and for formulating whatever they want to communicate. But of course I agree that animal languages are different from human languages in so far as ours are infinitely more complex. As far as I know, humans tend to speak the language that is spoken in their particular part of the world. I have never yet heard a newborn baby speak any human language at all, and when the toddler does start to speak, I have never heard him or her speak anything but what he or she has learned from his or her immediate surroundings. And if our author has studied languages in different parts of the world, he will know that the sounds, the vocabulary and the grammar differ from one language to another. And so while it is true that as far as we know, all languages have some form of grammar, and they all use words to which we have given various classifications - also using words - and they all use ways of linking words together, there is no such thing as a universal grammar, let alone one that is inborn, and this speaks to the “universality of the idea that, in a sense”, there are thousands of human languages. This discussion is one long quibble over terminology.
The argument is whether we are born with a basic mechanism in our brains for grammar and syntax, which would certainly suggest a designer introduced it into our current iteration of the human brain. I will differ with you. There are universal rules that seem to apply to all languages. The battle over recursion, however, seems to be difference over semantics. This author suggests strongly Everett is alone.
Human evolution; Chomsky Everett language fight
dhw: This discussion is one long quibble over terminology.
DAVID: The argument is whether we are born with a basic mechanism in our brains for grammar and syntax, which would certainly suggest a designer introduced it into our current iteration of the human brain. I will differ with you. There are universal rules that seem to apply to all languages. The battle over recursion, however, seems to be difference over semantics. This author suggests strongly Everett is alone.
All human languages consist of sequences of words/sounds which are joined together. The words/sounds themselves and the manner in which they are joined together vary from language to language, though there are common features between some languages. All children are born with the necessary mechanisms for LEARNING the words/sounds and the way they are joined together, and children learn these by copying what they hear in their immediate surroundings. “Rules” and terminology are our attempts to systematize our respective languages, and these have undergone many changes over thousands of years. Nobody so far as I know has managed to write a grammar book with "rules" that can be applied to all human languages at all times of their history. I suggest strongly that Everett is not alone. “Difference over semantics” is another way of saying quibbling over terminology.
An interesting digression: in what language would we and your God communicate now? (Ugh, maybe that’s why he remains hidden!)
Human evolution; Chomsky Everett language fight
by David Turell , Saturday, September 12, 2020, 18:03 (1531 days ago) @ dhw
dhw: This discussion is one long quibble over terminology.
DAVID: The argument is whether we are born with a basic mechanism in our brains for grammar and syntax, which would certainly suggest a designer introduced it into our current iteration of the human brain. I will differ with you. There are universal rules that seem to apply to all languages. The battle over recursion, however, seems to be difference over semantics. This author suggests strongly Everett is alone.
dhw: All human languages consist of sequences of words/sounds which are joined together. The words/sounds themselves and the manner in which they are joined together vary from language to language, though there are common features between some languages. All children are born with the necessary mechanisms for LEARNING the words/sounds and the way they are joined together, and children learn these by copying what they hear in their immediate surroundings. “Rules” and terminology are our attempts to systematize our respective languages, and these have undergone many changes over thousands of years. Nobody so far as I know has managed to write a grammar book with "rules" that can be applied to all human languages at all times of their history. I suggest strongly that Everett is not alone. “Difference over semantics” is another way of saying quibbling over terminology.
An interesting digression: in what language would we and your God communicate now? (Ugh, maybe that’s why he remains hidden!)
From what I have read the Chomsky theory is that there is an innate grammar and syntax in all of us at birth, to b e developed from listening. I confer with God in English. My German is weak and Yiddish very sketchy.
Human evolution; Chomsky Everett language fight
DAVID: From what I have read the Chomsky theory is that there is an innate grammar and syntax in all of us at birth, to b e developed from listening. I confer with God in English. My German is weak and Yiddish very sketchy.
Grammar and syntax do not have an independent existence from words, and I have never yet met any toddler who was able to put together sentences before first speaking isolated words. Children develop their vocabulary from listening, and they develop the ability to join words from listening. And different languages have different words and different ways of joining words, though many languages have certain elements of syntax in common. As for your conferences with God, has he ever joined in the conversation?
Human evolution; Chomsky Everett language fight
by David Turell , Sunday, September 13, 2020, 15:24 (1530 days ago) @ dhw
DAVID: From what I have read the Chomsky theory is that there is an innate grammar and syntax in all of us at birth, to b e developed from listening. I confer with God in English. My German is weak and Yiddish very sketchy.
dhw: Grammar and syntax do not have an independent existence from words, and I have never yet met any toddler who was able to put together sentences before first speaking isolated words. Children develop their vocabulary from listening, and they develop the ability to join words from listening. And different languages have different words and different ways of joining words, though many languages have certain elements of syntax in common. As for your conferences with God, has he ever joined in the conversation?
Not directly, but the evidence of His designs is overwhelming.
Human evolution; Chomsky Everett language fight II
by David Turell , Sunday, September 13, 2020, 18:11 (1530 days ago) @ David Turell
DAVID: From what I have read the Chomsky theory is that there is an innate grammar and syntax in all of us at birth, to b e developed from listening. I confer with God in English. My German is weak and Yiddish very sketchy.
dhw: Grammar and syntax do not have an independent existence from words, and I have never yet met any toddler who was able to put together sentences before first speaking isolated words. Children develop their vocabulary from listening, and they develop the ability to join words from listening. And different languages have different words and different ways of joining words, though many languages have certain elements of syntax in common. As for your conferences with God, has he ever joined in the conversation?
Not directly, but the evidence of His designs is overwhelming.
Had another thought. The argument is really from a different direction. Yes kids learn their native language by mimicking what their hear. However, as inventive as humans have turned out to be the claim is that all languages have the same basic structure with different words. That means something is innate.
Human evolution; Chomsky Everett language fight II
DAVID: Had another thought. The argument is really from a different direction. Yes kids learn their native language by mimicking what their hear. However, as inventive as humans have turned out to be the claim is that all languages have the same basic structure with different words. That means something is innate.
Different languages have different words AND different structures. But some languages have similar structures to those of other languages. What is innate is the desire and ability to communicate, as it is in all our fellow animals. The only basic structure that I know which is common to all human languages is that they consist of different words that are joined together in different ways. However, I am thinking of applying for a research grant to record the sounds newborn babies make all over the world, because although I do not believe in a universal grammar, I am developing a theory that all newborn babies start life with the same innate basic vocabulary.
Human evolution; Chomsky Everett language fight II
by David Turell , Monday, September 14, 2020, 18:02 (1529 days ago) @ dhw
DAVID: Had another thought. The argument is really from a different direction. Yes kids learn their native language by mimicking what their hear. However, as inventive as humans have turned out to be the claim is that all languages have the same basic structure with different words. That means something is innate.
dhw: Different languages have different words AND different structures. But some languages have similar structures to those of other languages. What is innate is the desire and ability to communicate, as it is in all our fellow animals. The only basic structure that I know which is common to all human languages is that they consist of different words that are joined together in different ways. However, I am thinking of applying for a research grant to record the sounds newborn babies make all over the world, because although I do not believe in a universal grammar, I am developing a theory that all newborn babies start life with the same innate basic vocabulary.
You and I are not linguists. But their majority theory is that is an innate language structure existing for humans.
Human evolution; wooden hunting stick found
by David Turell , Friday, April 24, 2020, 00:37 (1673 days ago) @ David Turell
Two feet long, sharpened at both ends. thrown to kill small animals:
https://www.smithsonianmag.com/smart-news/300000-year-old-throwing-stick-shows-human-an...
"A recently unearthed, 300,000-year-old wooden stick may have once been thrown by extinct human ancestors hunting wild game, according to new research.
***
"As the researchers report in the journal Nature Ecology & Evolution, the ancient wood was likely a throwing stick used by either Neanderthals or their even more ancient relatives, Homo heidelbergensis, to kill quarry like waterfowl and rabbits. (my bold)
"Archaeologists found the roughly two-foot long, half-pound throwing stick while conducting excavations in Schöningen, Germany, in 2016. To date, the site has yielded a trove of prehistoric weapons, including wooden spears and javelins thought to be the oldest ever discovered. This latest find adds to the ancient arsenal unearthed at Schöningen—and underscores the sophistication of early hominins as hunters and toolmakers.
“'We can show that already 300,000 years ago, not only are these late Homo heidelbergensis or very early Neanderthals at the top of the food chain,” Nicholas Conard, an archaeologist at University of Tübingen and the study’s lead author, tells the Times, “but they also have a whole range of important technological skills they can use to make sure they can feed themselves and lead their lives.”
***
'
“Throwing sticks are pointed at both ends, but that’s actually for the flight trajectory, it’s not for piercing,” she says.
***
"Analysis conducted by Rots revealed damage from apparent impacts similar to the kind seen on other throwing sticks.
“'They are effective weapons at diverse distances and can be used to kill or wound birds or rabbits or to drive larger game, such as the horses that were killed and butchered in large numbers in the Schöningen lakeshore,” explains Serangeli in a statement."
Comment: An interesting artifact. Note the bold as to who might have used it based on aging. the logic is they invented it.
Human evolution; new anthropological info
DAVID: I say God's decision, but He won't tell us His reasoning. Now let us guess....
dhw: Why all the different forms of homo? Either he was experimenting, or he had set in motion a mechanism that enabled all organisms to work out their own ways of survival. And so once the human line had begun, it branched out as different sets of humanoids and homos found their own means of coping with the environment.
DAVID: Try this possibility about my in-charge God: He set the evolution of Hominins and Homos in high drive just as in the Cambrian Explosion.
What do you mean by “set it in high drive”? Your theory all along has been that each step and each innovation was either preprogrammed 3.8 billion years ago or personally dabbled. The latter means he designed each one individually.
DAVID: The experiences of many different homo types in many different environments with their sexual intermingling gave the final sapiens all the various immune and environmental tolerance abilities they would need to go forward in living successfully.
And so your God, who only wants H. sapiens and is all-powerful and can create whatever he wants whenever he wants, has to preprogramme (3.8 billion years ago) or dabble not only 3.X billion years’ worth of non-human life forms, econiches, natural wonders etc. (including the Cambrian explosion) but also various types of hominins and homos before the programming or dabbling of the only species he wants to create. No wonder you tell us we shouldn’t try to work out his reasons – though you think providing food for 3.X billion years’ worth of non-human organisms explains everything.
QUOTE (from “erectus info”: "Combined with other evidence, this leads them to argue that the site reflects a period of transition in southern Africa driven by climatic variability, with endemic species such as Australopithecus going extinct, while new migrants – Homo and Paranthropus – moved in.
DAVID: Another new find that supports the idea of a hominin/homo evolutionary explosion.
Indeed, and the bigger the explosion, the more difficult it is to believe that your all-powerful God started out wanting only one species (apart from enough other life forms to provide H. sapiens with food). The explosion supports the idea of different species evolving to cope with different environments. Your theory once again raises the question of if or why your God created different environments.
Human evolution; new anthropological info
by David Turell , Friday, April 03, 2020, 22:10 (1693 days ago) @ dhw
DAVID: Try this possibility about my in-charge God: He set the evolution of Hominins and Homos in high drive just as in the Cambrian Explosion.
dhw: What do you mean by “set it in high drive”? Your theory all along has been that each step and each innovation was either preprogrammed 3.8 billion years ago or personally dabbled. The latter means he designed each one individually.
The Cambrian was a rapid expansion of new forms. So was the human. I assume both were a massive dabble.
DAVID: The experiences of many different homo types in many different environments with their sexual intermingling gave the final sapiens all the various immune and environmental tolerance abilities they would need to go forward in living successfully.dhw: And so your God, who only wants H. sapiens and is all-powerful and can create whatever he wants whenever he wants, has to preprogramme (3.8 billion years ago) or dabble not only 3.X billion years’ worth of non-human life forms, econiches, natural wonders etc. (including the Cambrian explosion) but also various types of hominins and homos before the programming or dabbling of the only species he wants to create. No wonder you tell us we shouldn’t try to work out his reasons – though you think providing food for 3.X billion years’ worth of non-human organisms explains everything.
You are rigidly opposed to the econiches and food supply argument as usual. Are you aware of the meat factories (chicken farming, beef herds, etc.) we have that many see as currently producing problems? Humans need a huge food supply and are constantly inventing ways to increase it. I'm sorry you cannot see God as I do, and are totally illogical about a God you constantly try to see from a human point of view, totally contrary to my views of God. No wonder we don't agree.
QUOTE (from “erectus info”: "Combined with other evidence, this leads them to argue that the site reflects a period of transition in southern Africa driven by climatic variability, with endemic species such as Australopithecus going extinct, while new migrants – Homo and Paranthropus – moved in.DAVID: Another new find that supports the idea of a hominin/homo evolutionary explosion.
dhw: Indeed, and the bigger the explosion, the more difficult it is to believe that your all-powerful God started out wanting only one species (apart from enough other life forms to provide H. sapiens with food). The explosion supports the idea of different species evolving to cope with different environments. Your theory once again raises the question of if or why your God created different environments.
The different species in different environments gave sapiens all the attributes it need as a final product. I've been over all is before, remember?
The Earth He created had many different environments in different areas and at different times in the history of the Earth. You don't see God as I do, so of course I see God at work.
Human evolution; new human cave art found
by David Turell , Friday, April 17, 2020, 22:50 (1679 days ago) @ David Turell
In an Indonesian cave:
https://www.scientificamerican.com/article/signs-of-modern-human-cognition-were-found-i...
"Imagining things that do not exist in nature and weaving them into narratives are unique signatures of the human psyche. These abilities are abundantly evident in the earliest example of narrative art, which was recently discovered in a cave on the Indonesian island of Sulawesi. In these newly reported images, one or more Pleistocene-epoch humans on this Southeast Asian island depicted a scene containing several figures that seem to be people. But mysteriously, some of these “humans” have snouts, another has a tail and still another has a bird’s beak. The human-animal hybrids must have lived only in the imagination of their creators. Far from a literal copy of the natural world, they offer a window into the creative minds of the prehistoric artists. The images’ inventive mixing of forms reveals a surprisingly modern reasoning and a sophisticated narrative imagination. At 44,000 years of age, they are the oldest known cave paintings made by modern humans
***
"The arrangement of the figures and the presence of strange humanlike forms suggests that the artists were conveying a story. But if these paintings represent a narrative, what does it mean? The individuals who resemble people carry what appear to be weapons or, in some cases, ropes. They surround a group of animals, which includes pigs and a species of dwarf buffalo, suggesting that they are hunting those creatures. Could this scene be a literal depiction of a hunt, with humans wearing animal skins or masks for camouflage? Alternatively, could it be a record of a hunting strategy?
***
"Sulawesi lies east of Borneo and northwest of Australia, and it is a particularly rich site for ancient art. More than 240 caves with wall paintings have been identified on the island. The researchers who announced the recent discovery previously described a 35,000-year-old cave painting of a babirusa, or pig deer, there. They also reported some examples of portable art in Sulawesi dating back 20,000 years, including engravings of an anoa (a wild ox sometimes called a midget buffalo) and of a sunburst pattern on plaquettes about the size of large coins.
***
"These evocative images, hidden until now in an Indonesian cave, are a combinatorial exploration of an imaginary world, mixing a human form with the head of a bird or the tail of a beast. The Sulawesi artists who composed the images left us the earliest example of the innovative combination of features and their symbolic meanings that became the heart of human culture. The painting show modern thought at work in a prehistoric cave."
Comment: H. sapiens traveled all over the world, getting to the Western Hemisphere very late. Note my bold. Sapiens arrived 315,000 years ago according to current knowledge. Look how long it took to learn how to use their new-sized brain. Dhw's theory of forced enlargement can be easily interpreted as meaning the new brain did not need a learning period like this.
Human evolution; erectus stockier
by David Turell , Tuesday, July 07, 2020, 20:50 (1598 days ago) @ David Turell
New study of whole teenage fossil, Turkana boy:
https://phys.org/news/2020-07-ancestral-commonalities-modern-human-body.html
"'That Homo erectus was perhaps not the lean, athletic long-distance runner we imagined is consistent with more recent fossil finds and larger body weight estimates than previously obtained," notes Fred Spoor of London's Natural History Museum and the paper's senior author. "This iconic ancestor was probably a little less like us than we portrayed it over the years."
"The work reveals for the first time what the three-dimensional shape of the ribcage of the Homo erectus skeleton, known as the Turkana Boy, looked like. Discovered west of Lake Turkana, Kenya in the mid-1980s, the 1.5-million-year-old fossil is the most complete skeleton of a fossil human ancestor ever found.
"Specifically, it had a deeper, wider and shorter chest than seen in modern humans, suggesting that Homo erectus had a stockier build than commonly assumed. It thus appears that the fully modern human body shape evolved more recently than scientists previously concluded, rather than as early as two million years ago—when Homo erectus first emerged.
"'The results are now changing our understanding of Homo erectus," says lead author Bastir. "Its thorax was much wider and more voluminous than that of most people living today."
"'Actually, the ribcage of Homo erectus seems more similar to that of more stocky human relatives such as Neandertals, who would have inherited that shape from Homo erectus," adds García Martínez.
"The evolution of the modern human body shape is a fascinating transformation in light of the way we and our ancestors are adapted to our natural environment, the scientists observe. As modern humans, we have a relatively tall, slender body shape that contrasts with the shorter, stocky, heavy bodied Neandertals."
Comment: Makes perfect sense, since it suggests a morphology more like Neanderthal which came from the same ancestor as sapiens. An adaptive change in the same species.
Human evolution; we speak, macaques don't
by David Turell , Saturday, July 11, 2020, 14:52 (1594 days ago) @ David Turell
They don't seem to have the right neural controls:
https://science.sciencemag.org/content/369/6500/155.3?utm_campaign=ec_sci_2020-07-09&am...
The anatomical organization of auditory cortical pathways in nonhuman primates (NHPs) shows remarkable similarities with humans. So why don't NHPs have a more speech-like communication system? Archakov et al. trained macaques to perform an auditory-motor task using a purpose-built piano. Mapping brain activity by functional magnetic resonance imaging showed that sound sequences activated the auditory midbrain and cortex. More importantly, sound sequences that had been learned by self-production also activated motor cortex and basal ganglia. This shows that monkeys can form auditory-motor links and that this is not the reason why they do not speak. Instead, the origin of speech in humans may have required the evolution of a command apparatus that controls the upper vocal tract.
Comment: Luck of the draw, or designer at work?
Human evolution; goosebumps
by David Turell , Friday, July 24, 2020, 18:38 (1581 days ago) @ David Turell
We get them from our past:
https://bigthink.com/surprising-science/goosebumps-hair
"A new study suggests that goosebumps are part of a larger system that not only keeps us warm, but also helps hair to heal.
:The sympathetic nerve system reacts to cold air with goose skin. If it stays on long enough, it orders new hair growth.
"The authors note that other, currently unknown, connections between this system and other parts of the body are likely to exist.
"Everybody gets goosebumps, but have you ever wondered why? Until now, the leading hypothesis was that by elevating hair-follicles on the skin, goosebumps helped keep the body warm by providing more space for warm air to be collect near the body. However, many scientists have puzzled over this explanation, as the lack of body hair on modern humans leaves us with the ability to have goose skin but without the ability to benefit from it.
***
"A new study published in Cell suggests a different reason for this reaction. Its authors argue that the same cells that cause goosebumps might be responsible for helping hair growth in the first place, giving a reason for evolution to retain this familiar phenomenon.
"In animals, many organs are made of three kinds of tissue: epithelium, mesenchyme, and nerve. In the skin, which is an organ, a nerve connects to muscle in the mesenchyme. This nerve is part of the sympathetic nervous system and helps maintain homeostasis. The muscle itself is connected to stem cells in the epithelium that heal wounds and regenerate hair follicles.
***
"The researchers examined the behavior and structure of the nerve under an electron microscope. To their surprise, the nerve was not only attached to the previously mentioned muscle tissue but also wrapped around hair follicle stem cells.
"In normal conditions, the sympathetic nervous system is always operating at a low level. This keeps the body functioning normally. When the researchers observed this behavior, they noticed signals being sent by the nervous system to the stem cells in the hair follicles. These signals seem to keep the stem cells at the ready for potential use.
"However, when the researchers exposed the tissues to the cold, the activity ramped up. A flood of neurotransmitters was released, and the stem cells activated. This prompted new hair growth to begin.
"Another experiment dove into how the nerve reached the stem cells in the first place.
***
""We discovered that the signal comes from the developing hair follicle itself. It secretes a protein that regulates the formation of the smooth muscle, which then attracts the sympathetic nerve. Then in the adult, the interaction turns around, with the nerve and muscle together regulating the hair follicle stem cells to regenerate the new hair follicle. It's closing the whole circle -- the developing hair follicle is establishing its own niche."
"Putting this together, it appears that goosebumps are part of a two-phased response to cold. In the first, the muscle below the skin is stimulated to form goosebumps. If this stimulation lasts long enough, the second phase kicks in, with the sympathetic nervous system calling for new hair growth and repairs for the old ones to be made in response to the cold."
Comment: Just an interesting leftover from the past.
Human evolution; Neanderthal pain gene
by David Turell , Friday, July 24, 2020, 18:52 (1581 days ago) @ David Turell
A 'probable' finding:
https://www.nature.com/articles/d41586-020-02202-x?utm_source=Nature+Briefing&utm_c...
"Despite their rough and tumble existence, Neanderthals had a biological predisposition to a heightened sense of pain, finds a first-of-its kind genome study published in Current Biology on 23 July1. Evolutionary geneticists found that the ancient human relatives carried three mutations in a gene encoding the protein NaV1.7, which conveys painful sensations to the spinal cord and brain. They also showed that in a sample of British people, those who had inherited the Neanderthal version of NaV1.7 tend to experience more pain than others.
***
"Mutations in a gene called SCN9A — which encodes the NaV1.7 protein — stood out because all of the Neanderthals had three mutations that alter the shape of the protein. The mutated version of the gene was found on both sets of chromosomes in all three Neanderthals, hinting that it was common across their populations.
"NaV1.7 acts in the body’s nerves, where it is involved in controlling whether and to what extent painful signals are transmitted to the spinal cord and brain. “People have described it as a volume knob, setting the gain of the pain in nerve fibres,” says Zeberg. Some people with extremely rare genetic mutations that disable the protein do not feel pain2, whereas other changes can predispose people to chronic pain.
***
"He and Pääbo then looked for humans with the Neanderthal version of NaV1.7. About 0.4% of participants in the UK Biobank, a genome database of half a million British people, who reported on their pain symptoms had one copy of the mutated gene. No one had two, like Neanderthals. Participants with the mutated version of the gene were about 7% more likely to report pain in their lives than were people without it.
***
"Pääbo and Zeberg caution that their findings do not necessarily mean that Neanderthals would have felt more pain than modern humans. Sensations conveyed by NaV1.7 are processed and modified in the spinal cord and brain, which also contribute to the subjective experience of pain.
***
"It is unclear whether the mutations evolved because they were beneficial. Neanderthal populations were small and had low genetic diversity — conditions that can help harmful mutations linger. But Pääbo says the change “smells” like a product of natural selection. He plans to sequence the genomes of around 100 Neanderthals, which could help provide answers.
"In any case, “pain is something adaptive”, points out Zeberg. “It’s not specifically bad to feel pain.'”
Comment: The study shows what we can learn by decoding DNA. I've always told patients pain is a friend as a helpful warning.
Human evolution; Neanderthal pain gene
DAVID: The study shows what we can learn by decoding DNA. I've always told patients pain is a friend as a helpful warning.
And I’m sure they screamed their appreciation.
Human evolution; Neanderthal pain gene
by David Turell , Saturday, July 25, 2020, 15:48 (1580 days ago) @ dhw
DAVID: The study shows what we can learn by decoding DNA. I've always told patients pain is a friend as a helpful warning.
dhw: And I’m sure they screamed their appreciation.
They all loved me.
Human evolution: changes in sialic acid changed immunity
by David Turell , Saturday, July 25, 2020, 18:35 (1580 days ago) @ David Turell
We are not immune to some infectious agents apes and others are immune to by a change in this acid which coats cells. It may have altered human evolution. See the bold:
https://www.sciencemag.org/news/2020/07/ancient-microbial-arms-race-sharpened-our-immun...
"Nissi Varki noted that humans suffer from a long list of deadly diseases—including typhoid fever, cholera, mumps, whooping cough, measles, smallpox, polio, and gonorrhea—that don’t afflict apes and most other mammals. All of those pathogens follow the same well-trodden pathway to break into our cells: They manipulate sugar molecules called sialic acids. Hundreds of millions of these sugars stud the outer surface of every cell in the human body—and the sialic acids in humans are different from those in apes.
***
"By analyzing modern human genomes and ancient DNA from our extinct cousins, the Neanderthals and Denisovans, the researchers detected a burst of evolution in our immune cells that occurred in an ancestor of all three types of human by at least 600,000 years ago.
***
"The arena for this evolutionary arms race is the glycocalyx, a sugar coating that protects the outer membrane of all cells. It consists of a forest of molecules that sprout from the cell membrane. The sialic acids are at the tip of the tallest branches, sugar chains called glycans, which are rooted to fats and proteins deeper in the membrane.
"Given their prominence and sheer number, sialic acids are usually the first molecules that invading pathogens encounter. Human cells are coated with one type of sialic acid, N-acetylneuraminic acid (Neu5Ac). But apes and most other mammals also carry a different one, N-glycolylneuraminic acid (Neu5Gc).
"More than 2 million years ago, according to multiple molecular clock methods, a mutation in the CMAH gene on chromosome six made it impossible for human ancestors to produce Neu5Gc anymore; instead, they made more of another sialic acid, Neu5Ac. “We now know we had an ancient complete makeover of the surface of the human cells,” says evolutionary biologist Pascal Gagneux of UCSD, a co-author of the new paper. Birds, some bats, ferrets, and New World monkeys all separately made the same evolutionary change.
"The change likely evolved as a defense against malaria, says UCSD physician-scientist Ajit Varki, senior author of the paper and Nissi Varki’s spouse. Malarial parasites that infect chimpanzees were no longer able to bind with the altered sialic acids on our red blood cells.
***
In past studies, Ajit Varki and Gagneux suggested the makeover of the cell and the loss of Neu5Gc may have even contributed to the origin of a new species in our genus Homo. If a woman with only Neu5Ac sialic acids mated with a man who still expressed Neu5Gc, her immune system may have rejected that man’s sperm or the fetus that developed from it. This fertility barrier might have helped divide Homo populations into different species more than 2 million years ago, the researchers speculated. (my bold)
***
"But the sialic acid change also sparked a new arms race between pathogens and our ancestors. In the new study, the researchers scanned DNA for immune genes in six Neanderthals, two Denisovans, and 1000 humans, and looked at dozens of chimps, bonobos, gorillas, and orangutans as well. They found evolutionary changes that “markedly altered” one class of proteins—sialic acid-binding immunoglobulin-type lectins, or Siglecs—that usually sit on the surface of human immune cells and recognize sialic acids.
"Siglecs are molecular sentries: They probe sialic acids to see whether they are familiar parts of our own bodies or foreign invaders. If Siglecs spot sialic acids that are damaged or missing, they signal immune cells to activate, rousing an inflammatory army to attack potential invaders or clean up damaged cells. If sialic acids instead appear to be normal parts of our own cells, other, inhibitory Siglecs throttle back immune defenses so as not to attack our own tissues
***
"Although the recently mutated Siglecs protect us from pathogens, they may also contribute to other diseases. Some of the genetically changed Siglecs are associated with inflammation and autoimmune disorders such as asthma and with meningitis. The researchers suggest the altered Siglecs may be constantly on high alert and do not dampen immune responses against our own tissues;
***
“'This nicely shows that … natural selection is not always going for the optimal solution, because the optimal solution is changing all the time,” says Rita Gerardy-Schahn, a glycobiologist...who was not part of the new work. “What is best for natural selection in the short run may be the wrong selection tomorrow.'”
Comment: The last comment demonstrates that the battle with pathogens is a constantly changing arena of struggle. Note the bold. A mutational error favored by natural selection or by God may have arranged for our human evolution.
Human evolution: resisting malaria
by David Turell , Wednesday, September 16, 2020, 20:53 (1527 days ago) @ David Turell
A new blood type in Africa does it:
https://medicalxpress.com/news/2020-09-dantu-blood-group-malariaand-humans.html
"The secret of how the Dantu genetic blood variant helps to protect against malaria has been revealed for the first time by scientists at the Wellcome Sanger Institute, the University of Cambridge and the KEMRI-Wellcome Trust Research Programme, Kenya. The team found that red blood cells in people with the rare Dantu blood variant have a higher surface tension that prevents them from being invaded by the world's deadliest malaria parasite, Plasmodium falciparum.
***
"In 2017, researchers discovered that the rare Dantu blood variant, which is found regularly only in parts of East Africa, provides some degree of protection against severe malaria. The intention behind this new study was to explain why.
"Red blood cell samples were collected from 42 healthy children in Kilifi, Kenya, who had either one, two or zero copies of the Dantu gene. The researchers then observed the ability of parasites to invade the cells in the laboratory, using multiple tools including time-lapse video microscopy to identify the specific step at which invasion was impaired.
"Analysis of the characteristics of the red blood cell samples indicated that the Dantu variant created cells with a higher surface tension—like a drum with a tighter skin. At a certain tension, malaria parasites were no longer able to enter the cell, halting their lifecycle and preventing their ability to multiply in the blood.
***
"The Dantu variant actually slightly increases the tension of the red blood cell surface. It's like the parasite still has the key to the lock, but the door is too heavy for it to open."
***
"The Dantu blood group has a novel 'chimeric' protein that is expressed on the surface of red blood cells, and alters the balance of other surface proteins. In Kilifi, a town on the Kenyan coast, 10 percent of the population have one copy of the Dantu gene, which confers up to 40 percent protection against malaria. One percent of the population have two copies, conferring up to 70 percent protection. By contrast, the best malaria vaccines currently provide 35 percent protection.
"Because humans have evolved alongside malaria for tens of thousands of years, some people in the worst affected areas have developed genetic resistance to the disease. The most famous example is sickle cell trait, which confers 80 percent resistance to malaria, but can cause serious illness in those with two copies of the gene. There is currently no evidence that the Dantu variant is accompanied by other health complications.
"Dr. Alejandro Marin-Menendez, of the Wellcome Sanger Institute, said: "The fact that we see the most protective adaptations in areas where malaria is most prevalent tells us a lot about how these parasites have influenced human evolution. Malaria is still an incredibly destructive disease, but evolutionary adaptations like sickle cell trait and the Dantu variant may partially explain why the mortality rate is much lower than the rate of infection. We've been fighting malaria parasites for as long as we've been human, so there may be other adaptations and mechanisms yet to be discovered.'"
Comment: Another way malaria is blocked in this case by surface tension of the cells. A beneficial mutation is an existing species.
Human evolution; Neanderthal pain gene
DAVID: The study shows what we can learn by decoding DNA. I've always told patients pain is a friend as a helpful warning.
dhw: And I’m sure they screamed their appreciation.
DAVID: They all loved me.
Now that is a theory which I really can believe. Followers of this forum might well imagine that David and I are permanently at daggers drawn, so I will take this opportunity to redress the balance. We met just once, six and a half years ago, when he and his wife came to England. It’s hard to imagine a more delightful couple, and the bond of friendship remains as strong as ever. I regard it as a privilege to know him, and our battles on this forum do not detract one iota from my respect, admiration and affection for a truly remarkable man.
Human evolution; Neanderthal pain gene
by David Turell , Sunday, July 26, 2020, 15:35 (1579 days ago) @ dhw
DAVID: The study shows what we can learn by decoding DNA. I've always told patients pain is a friend as a helpful warning.
dhw: And I’m sure they screamed their appreciation.
DAVID: They all loved me.
dhw: Now that is a theory which I really can believe. Followers of this forum might well imagine that David and I are permanently at daggers drawn, so I will take this opportunity to redress the balance. We met just once, six and a half years ago, when he and his wife came to England. It’s hard to imagine a more delightful couple, and the bond of friendship remains as strong as ever. I regard it as a privilege to know him, and our battles on this forum do not detract one iota from my respect, admiration and affection for a truly remarkable man.
Well, I guess it is the time to reveal the truth. We are firm friends with a difference of opinion. And my feelings for dhw equal his. Is it really six and a half years ago? Remembered like yesterday, the house, the wonderful gifted family.
Human evolution; goosebumps
QUOTE: "Putting this together, it appears that goosebumps are part of a two-phased response to cold. In the first, the muscle below the skin is stimulated to form goosebumps. If this stimulation lasts long enough, the second phase kicks in, with the sympathetic nervous system calling for new hair growth and repairs for the old ones to be made in response to the cold."
I have been bald since my mid thirties. I am now going to shut myself in the freezer for 24 hours. If you don’t hear from me again, I hereby bequeathe my curly-haired remains to the local barber shop.
Human evolution; goosebumps
by David Turell , Saturday, July 25, 2020, 15:47 (1580 days ago) @ dhw
QUOTE: "Putting this together, it appears that goosebumps are part of a two-phased response to cold. In the first, the muscle below the skin is stimulated to form goosebumps. If this stimulation lasts long enough, the second phase kicks in, with the sympathetic nervous system calling for new hair growth and repairs for the old ones to be made in response to the cold."
dhw: I have been bald since my mid thirties. I am now going to shut myself in the freezer for 24 hours. If you don’t hear from me again, I hereby bequeathe my curly-haired remains to the local barber shop.
If my memory is correct your sons didn't inherit from you, But it keeps your brain quite cool.
Human evolution: hairless
by David Turell , Friday, July 31, 2020, 23:16 (1574 days ago) @ David Turell
We are the only advanced mammals with little hair and sweat glands:
https://www.sciencedirect.com/science/article/pii/S0047248416000300?dgcid=raven_sd_reco...
"On balance, then, a combination of energy savings with thermal benefits and locomotor advantages would seem to provide the most likely selection pressures favouring bipedalism in the australopiths, with the locomotor advantages probably becoming increasingly important with Homo in order to facilitate a more nomadic ranging pattern and the occupation of lower altitude habitats under significantly cooler thermal regimes.
"Our results suggest that, while hair loss would have provided australopiths with substantial thermal advantages in more open habitats, the night time costs of reduced fur cover were very considerable and thus likely to militate against it so long as the australopiths occupied moderately high altitude habitats. Hairlessness would seem to have necessitated strategies to counteract overnight cooling and/or the occupation of lower altitude habitats. Heat loss at night can be reduced by the use of caves (which can raise mean ambient temperatures by as much as 4 °C
***
"Although caves probably have been used as night time refuges intermittently throughout hominin evolution, the use of caves may not have become a regular feature until hominins developed home bases, and that may have coincided with control over fire and the acquisition of a more human-like life history around 500 ka,
***
"A more plausible suggestion is that hair loss appeared with the arrival of Homo around 2.0 Ma, once the climate cooling that set in after 2.5 Ma allowed hominins to occupy somewhat lower altitude habitats. It is doubtful that australopiths were sufficiently mobile to make hair loss advantageous, but the appearance of a genus with a body shape better adapted to long distance travel (Homo ergaster locomotion was ∼50% more efficient energetically than that of early australopiths), combined with the first uncontroversial evidence for the occupation of lower altitude (including coastal) habitats (as evidenced by the fact that H. ergaster was able to migrate out of Africa into Eurasia quite soon after its first appearance), might signal the appearance of a suite of adaptations enabling greater mobility in more open, hotter habitats. Hair loss may thus be a peculiarity of our genus, and may have played a small but important role in allowing Homo to escape the confines of Africa."
Comment: Hair loss is certainly peculiar to our species. Sweating which also appeared with loss of hair is also an attribute which helps us during high energy exercise activities. What is odd is horses sweat, even while very hairy.
Human evolution: fire use and comfort lifestyle
by David Turell , Thursday, August 13, 2020, 21:31 (1561 days ago) @ David Turell
Evidence of fire use and natural bedding use is at least one million years old in South
Africa:
https://www.sciencenews.org/article/oldest-grass-beds-insect-repellent
"People living in southern Africa around 200,000 years ago not only slept on grass bedding but occasionally burned it, apparently to keep from going buggy.
"Remnants of the oldest known grass bedding, discovered in South Africa’s Border Cave, lay on the ashes of previously burned bedding, say archaeologist Lyn Wadley of the University of the Witwatersrand in Johannesburg and her colleagues. Ash spread beneath bound bunches of grass may have been used to repel crawling, biting insects, which cannot easily move through fine powder, the researchers report in the Aug. 14 Science. Wadley’s team also found bits of burned wood in the bedding containing fragments of camphor leaves, an aromatic plant that can be used as a bug repellent.
"Prior to this new find, the oldest plant bedding — mainly consisting of sedge leaves, ash and aromatic plants likely used to keep insects away — dated to around 77,000 years ago at South Africa’s Sibudu rock-shelter.
***
"At Border Cave, chemical and microscopic analyses of excavated sediment showed that a series of beds had been assembled from grasses, such as Guinea grass and red grass. Guinea grass currently grows at Border Cave’s entrance. Bedding past its prime was likely burned in small fire pits, the researchers suspect. Remains of fire pits were found not far from Border Cave’s former grass beds.
"Humans in southern Africa intentionally lit fires by around 1 million years ago (SN: 4/2/12). But Border Cave provides the first evidence that ancient grass bedding was burned on purpose.
"Small, sharpened stones were also found among grass and ash remains, suggesting that people occasionally sat on cave bedding while making stone tools."
Comment: I assume this advance in lifestyle was among the later branches of H. erectus people employing more extensive use of their brain development.
Human evolution: fire use and comfort lifestyle
by David Turell , Thursday, August 13, 2020, 22:00 (1561 days ago) @ David Turell
Evidence of fire use is at least one million years, but the use of natural bedding is 220,00 years old in South Africa:
https://www.sciencenews.org/article/oldest-grass-beds-insect-repellent
"People living in southern Africa around 200,000 years ago not only slept on grass bedding but occasionally burned it, apparently to keep from going buggy.
"Remnants of the oldest known grass bedding, discovered in South Africa’s Border Cave, lay on the ashes of previously burned bedding, say archaeologist Lyn Wadley of the University of the Witwatersrand in Johannesburg and her colleagues. Ash spread beneath bound bunches of grass may have been used to repel crawling, biting insects, which cannot easily move through fine powder, the researchers report in the Aug. 14 Science. Wadley’s team also found bits of burned wood in the bedding containing fragments of camphor leaves, an aromatic plant that can be used as a bug repellent.
"Prior to this new find, the oldest plant bedding — mainly consisting of sedge leaves, ash and aromatic plants likely used to keep insects away — dated to around 77,000 years ago at South Africa’s Sibudu rock-shelter.
***
"At Border Cave, chemical and microscopic analyses of excavated sediment showed that a series of beds had been assembled from grasses, such as Guinea grass and red grass. Guinea grass currently grows at Border Cave’s entrance. Bedding past its prime was likely burned in small fire pits, the researchers suspect. Remains of fire pits were found not far from Border Cave’s former grass beds.
"Humans in southern Africa intentionally lit fires by around 1 million years ago (SN: 4/2/12). But Border Cave provides the first evidence that ancient grass bedding was burned on purpose.
"Small, sharpened stones were also found among grass and ash remains, suggesting that people occasionally sat on cave bedding while making stone tools."
Comment: I assume this advance in lifestyle was among the early branches of H. sapiens people employing more extensive use of their brain development. The million year old fire use was back in erectus times.
Human evolution: rapid genome changes
by David Turell , Friday, August 14, 2020, 22:11 (1560 days ago) @ David Turell
Called HAR's, they caused our rapid evolution:
https://www.sciencedirect.com/science/article/pii/S0959437X14000781?dgcid=raven_sd_reco...
Abstract:
"Human accelerated regions (HARs) are DNA sequences that changed very little throughout mammalian evolution, but then experienced a burst of changes in humans since divergence from chimpanzees. This unexpected evolutionary signature is suggestive of deeply conserved function that was lost or changed on the human lineage. Since their discovery, the actual roles of HARs in human evolution have remained somewhat elusive, due to their being almost exclusively non-coding sequences with no annotation. Ongoing research is beginning to crack this problem by leveraging new genome sequences, functional genomics data, computational approaches, and genetic assays to reveal that many HARs are developmental gene regulatory elements and RNA genes, most of which evolved their uniquely human mutations through positive selection before divergence of archaic hominins and diversification of modern humans."
Comment: this is couched in Darwinian terms, but it just as well could be attributed to how God handled it.
Human evolution: hominin bone & ,flint tools
by David Turell , Saturday, August 15, 2020, 01:01 (1559 days ago) @ David Turell
Created by H. heidelbergenis in southern England, aged 480,000 years old:
https://www.smithsonianmag.com/smart-news/europes-earliest-bone-tools-hint-early-homini...
"Some 480,000 years ago, a group of 30 to 40 early hominins met at a rocky gravel pit in what is now southern England for a sumptuous feast. As detailed in a statement, the crowd—equipped with stone hammers and sharpened flint hand axes—gathered around the carcass of a large female horse and started breaking it down, stripping the creature of every ounce of flesh, harvesting its internal organs and even cracking its bones to suck out the fatty marrow.
***
"Per the Conversation, the ancient hominins active at Boxgrove needed bone hammers to make flint blades, as well as other stone tools discovered at the site. Some of the butchered horse’s knee and leg bones bear signs of such use.
***
“'Along with the careful butchery of the horse and the complex social interaction hinted at by the stone refitting patterns, it provides further evidence that early human population at Boxgrove were cognitively, social and culturally sophisticated,” she says in the statement.
***
"Though the horse may have been hunted, researchers have yet to find any evidence confirming this theory, the archaeologist adds.
"The horse butchery site’s proximity to the shoreline may explain its extraordinary preservation, Pope tells BBC News. At low tide, the carcass was left exposed, but when the tide came in, it covered the remains in fine, powdery silt and clay, gently freezing the scene in time.
"Now, reports Paul Rincon for BBC News, archaeologists have identified the millennia-old bone tools crafted out of the horse’s remains as the oldest ever found in Europe. Excavations at Boxgrove, a Middle Pleistocene site in West Sussex, unearthed the instruments in the 1980s and ’90s.
“'These are some of the earliest non-stone tools found in the archaeological record of human evolution,” says Simon Parfitt, an archaeologist at UCL and co-author of the new book, in the statement. “They would have been essential for manufacturing the finely made flint knives found in the wider Boxgrove landscape.”
"Silvia Bello, a paleoanthropologist at the London Natural History Museum who conducted a detailed analysis of the bone artifacts, adds that the Boxgrove tools demonstrate H. heidelbergensis’ understanding of different materials’ properties.
“'Along with the careful butchery of the horse and the complex social interaction hinted at by the stone refitting patterns, it provides further evidence that early human population at Boxgrove were cognitively, social and culturally sophisticated,” she says in the statement.
The horse butchery site’s proximity to the shoreline may explain its extraordinary preservation, Pope tells BBC News. At low tide, the carcass was left exposed, but when the tide came in, it covered the remains in fine, powdery silt and clay, gently freezing the scene in time.
"In the statement, Pope says precise mapping of such a pristine site allows scholars “to get as close as we can to witnessing the minute-by-minute movement and behaviors of a single apparently tight-knit group of early humans: a community of people, young and old, working together in a co-operative and highly social way.'”
Comment: Hominins were social and certainly formed groups as hunter-gatherers. Amazing archaeological discovery.
Human evolution: hominin bone & ,flint tools
https://www.smithsonianmag.com/smart-news/europes-earliest-bone-tools-hint-early-homini...
QUOTES: “'Along with the careful butchery of the horse and the complex social interaction hinted at by the stone refitting patterns, it provides further evidence that early human population at Boxgrove were cognitively, social and culturally sophisticated,” she says in the statement.”
"In the statement, Pope says precise mapping of such a pristine site allows scholars “to get as close as we can to witnessing the minute-by-minute movement and behaviors of a single apparently tight-knit group of early humans: a community of people, young and old, working together in a co-operative and highly social way.'”
DAVID: Hominins were social and certainly formed groups as hunter-gatherers. Amazing archaeological discovery.
Thank you for what is indeed another amazing eye-opener. We are gradually learning that our very ancient ancestors were far more advanced than sapiens would like to believe. Already the image of Neanderthalers has undergone a revolution in recent times, and now it seems that the much older Heidelbergers can join the ranks of the cognitively, social and culturally sophisticated. With regard to another of our recent discussions, does anybody seriously believe that they were able to achieve all this without a language of their own?
Human evolution: hominin bone & ,flint tools
by David Turell , Saturday, August 15, 2020, 20:38 (1559 days ago) @ dhw
https://www.smithsonianmag.com/smart-news/europes-earliest-bone-tools-hint-early-homini...
QUOTES: “'Along with the careful butchery of the horse and the complex social interaction hinted at by the stone refitting patterns, it provides further evidence that early human population at Boxgrove were cognitively, social and culturally sophisticated,” she says in the statement.”
"In the statement, Pope says precise mapping of such a pristine site allows scholars “to get as close as we can to witnessing the minute-by-minute movement and behaviors of a single apparently tight-knit group of early humans: a community of people, young and old, working together in a co-operative and highly social way.'”
DAVID: Hominins were social and certainly formed groups as hunter-gatherers. Amazing archaeological discovery.
dhw: Thank you for what is indeed another amazing eye-opener. We are gradually learning that our very ancient ancestors were far more advanced than sapiens would like to believe. Already the image of Neanderthalers has undergone a revolution in recent times, and now it seems that the much older Heidelbergers can join the ranks of the cognitively, social and culturally sophisticated. With regard to another of our recent discussions, does anybody seriously believe that they were able to achieve all this without a language of their own?
I'm with you. They had simple word sounds and hand gestures, just as we use our hands today to expand our spoken meanings.
Human evolution: Neanderthal Y chromosome
by David Turell , Friday, September 25, 2020, 12:49 (1518 days ago) @ David Turell
Somewhat of mystery:
https://www.sciencemag.org/news/2020/09/how-neanderthals-lost-their-y-chromosome?utm_ca...
"Neanderthals have long been seen as uber-masculine hunks, at least compared with their lightweight human cousins, with whom they competed for food, territory, and mates. But a new study finds Homo sapiens men essentially emasculated their brawny brethren when they mated with Neanderthal women more than 100,000 years ago. Those unions caused the modern Y chromosomes to sweep through future generations of Neanderthal boys, eventually replacing the Neanderthal Y.
"The new finding may solve the decade-old mystery of why researchers have been unable to find a Neanderthal Y chromosome. Part of the problem was the dearth of DNA from men: Of the dozen Neanderthals whose DNA has been sequenced so far, most is from women, as the DNA in male Neanderthal fossils happened to be poorly preserved or contaminated with bacteria.
***
"The best scenario to explain the Y pattern is that early modern human men mated with Neanderthal women more than 100,000 but less than 370,000 years ago, according to the team’s computational models. Their sons would have carried the modern human Y chromosome, which is paternally inherited. The modern Y then rapidly spread through their offspring to the small populations of Neanderthals in Europe and Asia, replacing the Neanderthal Y, the researchers report today in Science. Interestingly, the modern human mates were not ancestors to today’s H. sapiens—but were likely part of a population that migrated early out of Africa and then went extinct. Traces of Neanderthal DNA in living humans were inherited from a separate mixing event between 50,000 and 70,000 years ago.
"Researchers aren’t sure exactly why the replacement happened. Natural selection may have favored the H. sapiens Y chromosome, because Neanderthals had more deleterious mutations across their genomes, Kelso says. Neanderthals had smaller populations than moderns, and small populations tend to accumulate deleterious mutations, especially on the X and Y sex chromosomes. Modern humans, with their bigger, more genetically diverse ancestral populations, may have had a genetic advantage. Another possibility is that once Neanderthals had inherited a modern human mtDNA, their cells might have favored interaction with the modern human Y, says computational biologist Adam Siepel of Cold Spring Harbor Laboratory, who was not part of the study."
Comment: Still sorting out our evolution. Note the bold about deleterious mutations in small populations an opposite point to small populations creating punctuated equilibrium. Lots of Darwin theory is just supposition.
Human evolution: Neanderthal Y chromosome
QUOTE: Neanderthals had smaller populations than moderns, and small populations tend to accumulate deleterious mutations, especially on the X and Y sex chromosomes. (David’s bold)
DAVID: Still sorting out our evolution. Note the bold about deleterious mutations in small populations an opposite point to small populations creating punctuated equilibrium. Lots of Darwin theory is just supposition.
Sorry, but I think you’re getting confused. Punctuated equilibrium is Gould’s theory (not Darwin’s) that speciation occurs in bursts between long periods of stasis. The opposite of Darwin’s gradualism. I thought it was already a known fact that interbreeding within small numbers is liable to produce deleterious mutations. But as you rightly pointed out on the corvid thread:
DAVID: Hominins and homos were in small population numbers before we advanced 50,000 years ago and began to build a large population. This fits Gould's concept of small isolated populations causing rapid or large evolutionary advances.
Hence my proposal that sapiens may have branched off from the apes because local conditions may have forced particular groups to descend from the trees, whereas elsewhere the apes were able to carry on as before.
Human evolution: Neanderthal Y chromosome
by David Turell , Saturday, September 26, 2020, 16:08 (1517 days ago) @ dhw
QUOTE: Neanderthals had smaller populations than moderns, and small populations tend to accumulate deleterious mutations, especially on the X and Y sex chromosomes. (David’s bold)
DAVID: Still sorting out our evolution. Note the bold about deleterious mutations in small populations an opposite point to small populations creating punctuated equilibrium. Lots of Darwin theory is just supposition.
dhw: Sorry, but I think you’re getting confused. Punctuated equilibrium is Gould’s theory (not Darwin’s) that speciation occurs in bursts between long periods of stasis. The opposite of Darwin’s gradualism. I thought it was already a known fact that interbreeding within small numbers is liable to produce deleterious mutations.
You are correct. My problem is with the distortions of the purveyors of his theory.
dhw: But as you rightly pointed out on the corvid thread:
DAVID: Hominins and homos were in small population numbers before we advanced 50,000 years ago and began to build a large population. This fits Gould's concept of small isolated populations causing rapid or large evolutionary advances.
dhw: Hence my proposal that sapiens may have branched off from the apes because local conditions may have forced particular groups to descend from the trees, whereas elsewhere the apes were able to carry on as before.
Well, what does fit is that the early forms walked upright while still having heavy tree climbing upper body and small brains. You appeal to a natural cause while I favor God. But first all were groups of apes using trees. Do trees suddenly disappear over night? No, it was gradual, which means the ape groups could easily followed the retreat of the trees. Your natural theory, as usual, has huge holes.
Human evolution: Neanderthal Y chromosome
DAVID: Hominins and homos were in small population numbers before we advanced 50,000 years ago and began to build a large population. This fits Gould's concept of small isolated populations causing rapid or large evolutionary advances.
dhw: Hence my proposal that sapiens may have branched off from the apes because local conditions may have forced particular groups to descend from the trees, whereas elsewhere the apes were able to carry on as before.
DAVID: Well, what does fit is that the early forms walked upright while still having heavy tree climbing upper body and small brains. You appeal to a natural cause while I favor God.
What do you favour? Did your God preprogramme upright walking semi-apes, or did he step in and do a dabble on the legs, leaving chests and brains alone until the next dabble? Why do you think he would preprogramme or dabble these interim changes?What purpose would they have served unless it was to meet some new requirement?
DAVID: But first all were groups of apes using trees. Do trees suddenly disappear over night? No, it was gradual, which means the ape groups could easily followed the retreat of the trees. Your natural theory, as usual, has huge holes.
You have just agreed that isolated populations cause large evolutionary advances. An isolated group of apes would be isolated for a reason. They would not “easily follow” anything that took them out of their isolation. But of course this is all speculation. Maybe tree life wasn't providing enough food for our little group of explorers. Or maybe there was too much competition. Meanwhile, I’ll be interested to hear your answers to my questions above.
Human evolution: Neanderthal Y chromosome
by David Turell , Sunday, September 27, 2020, 16:10 (1516 days ago) @ dhw
DAVID: Hominins and homos were in small population numbers before we advanced 50,000 years ago and began to build a large population. This fits Gould's concept of small isolated populations causing rapid or large evolutionary advances.
dhw: Hence my proposal that sapiens may have branched off from the apes because local conditions may have forced particular groups to descend from the trees, whereas elsewhere the apes were able to carry on as before.
DAVID: Well, what does fit is that the early forms walked upright while still having heavy tree climbing upper body and small brains. You appeal to a natural cause while I favor God.
dhw: What do you favour? Did your God preprogramme upright walking semi-apes, or did he step in and do a dabble on the legs, leaving chests and brains alone until the next dabble? Why do you think he would preprogramme or dabble these interim changes?What purpose would they have served unless it was to meet some new requirement?
As usual you view it backwards to my approach. Upright posture allowed hands to become more dexterous, which in and of itself, will drive develop of new requirements in the activities that could be performed. Humans have the ability to invent new activities for themselves.
DAVID: But first all were groups of apes using trees. Do trees suddenly disappear over night? No, it was gradual, which means the ape groups could easily followed the retreat of the trees. Your natural theory, as usual, has huge holes.dhw: You have just agreed that isolated populations cause large evolutionary advances. An isolated group of apes would be isolated for a reason. They would not “easily follow” anything that took them out of their isolation. But of course this is all speculation. Maybe tree life wasn't providing enough food for our little group of explorers. Or maybe there was too much competition. Meanwhile, I’ll be interested to hear your answers to my questions above.
Answered.
Human evolution: Neanderthal Y chromosome
DAVID: Hominins and homos were in small population numbers before we advanced 50,000 years ago and began to build a large population. This fits Gould's concept of small isolated populations causing rapid or large evolutionary advances.
dhw: Hence my proposal that sapiens may have branched off from the apes because local conditions may have forced particular groups to descend from the trees, whereas elsewhere the apes were able to carry on as before.
DAVID: Well, what does fit is that the early forms walked upright while still having heavy tree climbing upper body and small brains. You appeal to a natural cause while I favor God.
dhw: What do you favour? Did your God preprogramme upright walking semi-apes, or did he step in and do a dabble on the legs, leaving chests and brains alone until the next dabble? Why do you think he would preprogramme or dabble these interim changes?What purpose would they have served unless it was to meet some new requirement?
DAVID: As usual you view it backwards to my approach. Upright posture allowed hands to become more dexterous, which in and of itself, will drive develop of new requirements in the activities that could be performed. Humans have the ability to invent new activities for themselves.
You have not answered my questions! But yes, our views are directly opposite. As I understand it, your theory is that your God fiddled with our ancestors’ anatomy BEFORE they descended from the trees. I propose that they descended for a reason, and their anatomy changed as a RESULT of their spending more time on the ground. I would also propose that life on the ground provided them with more opportunities to use their hands, which became more dexterous as a result. It’s not clear to me whether you think your God fiddled with their hands as well as their legs. It’s the same problem as with the whale’s fins and the human brain. You have your God preprogramming or dabbling every change in anticipation of new requirements, whereas I propose that fins and enlarged brains are the result of new requirements.
DAVID: But first all were groups of apes using trees. Do trees suddenly disappear over night? No, it was gradual, which means the ape groups could easily followed the retreat of the trees. Your natural theory, as usual, has huge holes.
dhw: You have just agreed that isolated populations cause large evolutionary advances. An isolated group of apes would be isolated for a reason. They would not “easily follow” anything that took them out of their isolation. But of course this is all speculation. Maybe tree life wasn't providing enough food for our little group of explorers. Or maybe there was too much competition. Meanwhile, I’ll be interested to hear your answers to my questions above.
DAVID: Answered.
Not answered. Nor have you responded to my argument concerning isolated populations.
Human evolution: A whale at altitude in Kenya
by David Turell , Monday, September 28, 2020, 14:49 (1515 days ago) @ dhw
A 17 million year old whale fossil in Turkana basin:
https://wattsupwiththat.com/2020/09/27/new-study-to-uncover-how-climate-change-and-tect...
A 17 million-year-old whale fossil discovered in the 1970s is the impetus for new research by an international team led by Stony Brook University that takes a unique approach to uncovering the course of mammalian evolution in East Africa.
The whale fossil represents a massive change from the Miocene to today in Kenya’s Turkana Basin, as the fossil of this sea animal was originally found 740 miles inland and 620 meters in elevation – an indication perhaps of a transformed geological and ecological landscape with the open-ended question: Why was the whale there?
***
“A longstanding question at the intersection of Earth and Life Sciences is: What roles, if any, do climate and tectonics play in the evolution of life? The East African Rift is among the best places to study the influences of Earth processes on the evolution of mammals,” explains Isaiah Nengo, PhD, Principal Investigator, Professor of Anthropology and Associate Director of Stony Brook University’s Turkana Basin Institute (TBI). “Here, uniquely, the region’s geologic and climate histories, including the formation of the rift system that is the cradle of humankind, are preserved in sedimentary rocks. Our collaborative work will tease out how tectonics and climate come together to drive evolution.”
***
It is estimated that the human-chimpanzee common ancestor evolved approximately 7.5 million years ago (mya) and diverged from the common ancestor with the gorilla ancestor about 9.3 mya. Meanwhile, the common ancestor of the great apes and humans is estimated to have diverged from the ancestor of the gibbons and siamangs approximately 19.1 mya. All these key divergence events would have occurred in the time period known as the Miocene (from about 23 mya to 5 mya).
Professor Nengo will collaborate with Stony Brook Geosciences Professors and co-investigators Gregory Henkes and William Holt, along with the international team. They will explore relationships between tectonics, climate, and mammal evolution in the Turkana Basin using integrated field, laboratory, and modeling studies.
New and existing data will be combined to study the links between rift development, climate change, and their respective roles in vegetation and mammal evolution.
Comment: This will be a very important study dealing with changing climate and the tectonic lifting of a sea area that had whales right in the birthplace of the human line of evolution.
Human evolution: Neanderthal Y chromosome
by David Turell , Monday, September 28, 2020, 15:26 (1515 days ago) @ dhw
edited by David Turell, Monday, September 28, 2020, 15:34
DAVID: Hominins and homos were in small population numbers before we advanced 50,000 years ago and began to build a large population. This fits Gould's concept of small isolated populations causing rapid or large evolutionary advances.
dhw: Hence my proposal that sapiens may have branched off from the apes because local conditions may have forced particular groups to descend from the trees, whereas elsewhere the apes were able to carry on as before.
DAVID: Well, what does fit is that the early forms walked upright while still having heavy tree climbing upper body and small brains. You appeal to a natural cause while I favor God.
dhw: What do you favour? Did your God preprogramme upright walking semi-apes, or did he step in and do a dabble on the legs, leaving chests and brains alone until the next dabble? Why do you think he would preprogramme or dabble these interim changes? What purpose would they have served unless it was to meet some new requirement?
DAVID: As usual you view it backwards to my approach. Upright posture allowed hands to become more dexterous, which in and of itself, will drive develop of new requirements in the activities that could be performed. Humans have the ability to invent new activities for themselves.
dhw: You have not answered my questions! But yes, our views are directly opposite. As I understand it, your theory is that your God fiddled with our ancestors’ anatomy BEFORE they descended from the trees. I propose that they descended for a reason, and their anatomy changed as a RESULT of their spending more time on the ground. I would also propose that life on the ground provided them with more opportunities to use their hands, which became more dexterous as a result. It’s not clear to me whether you think your God fiddled with their hands as well as their legs. It’s the same problem as with the whale’s fins and the human brain. You have your God preprogramming or dabbling every change in anticipation of new requirements, whereas I propose that fins and enlarged brains are the result of new requirements.
No need to change or repeat my known answers. God designs what is needed for each new advance, anticipating new abilities and activities.
DAVID: But first all were groups of apes using trees. Do trees suddenly disappear over night? No, it was gradual, which means the ape groups could easily followed the retreat of the trees. Your natural theory, as usual, has huge holes.dhw: You have just agreed that isolated populations cause large evolutionary advances. An isolated group of apes would be isolated for a reason. They would not “easily follow” anything that took them out of their isolation. But of course this is all speculation. Maybe tree life wasn't providing enough food for our little group of explorers. Or maybe there was too much competition. Meanwhile, I’ll be interested to hear your answers to my questions above.
DAVID: Answered.
dhw: Not answered. Nor have you responded to my argument concerning isolated populations.
Isolated populations are also subject to deleterious mutations which destroy the group.
Answered several days ago in a comment you removed in your next reply:
Saturday, September 26, 2020, 11:22 (2 days ago) @ David Turell
QUOTE: Neanderthals had smaller populations than moderns, and small populations tend to accumulate deleterious mutations, especially on the X and Y sex chromosomes. (David’s bold)
Human evolution: Neanderthal Y chromosome
dhw: You have your God preprogramming or dabbling every change in anticipation of new requirements, whereas I propose that fins and enlarged brains are the result of new requirements.
DAVID: No need to change or repeat my known answers. God designs what is needed for each new advance, anticipating new abilities and activities.
Understood. So now will you please answer my questions: Did your God preprogramme upright walking semi-apes, or did he step in and do a dabble on the legs, leaving chests and brains alone until the next dabble? Why do you think he would preprogramme or dabble these interim changes? What purpose would they have served unless it was to meet some new requirement?
dhw: ...Nor have you responded to my argument concerning isolated populations.
DAVID: Answered several days ago in a comment you removed in your next reply:
Saturday, September 26, 2020, 11:22 (2 days ago) @ David Turell
QUOTE: Neanderthals had smaller populations than moderns, and small populations tend to accumulate deleterious mutations, especially on the X and Y sex chromosomes. (David’s bold)
That had nothing to do with the exchange I’m talking about, which I reproduce below. You challenged my proposal – in line with Gould’s theory – that isolated groups of pre-humans would have taken to life on the ground while the rest of their species lived happily ever after in the trees.
DAVID: But first all were groups of apes using trees. Do trees suddenly disappear over night? No, it was gradual, which means the ape groups could easily followed the retreat of the trees. Your natural theory, as usual, has huge holes.
dhw: You have just agreed that isolated populations cause large evolutionary advances. An isolated group of apes would be isolated for a reason. They would not “easily follow” anything that took them out of their isolation. But of course this is all speculation. Maybe tree life wasn't providing enough food for our little group of explorers. Or maybe there was too much competition.
May I presume from your silence that you now accept this as a possible explanation for some apes changing and others staying the same?
QUOTE UNDER “Human evolution A whale at altitude in Kenya”): “Here, uniquely, the region’s geologic and climate histories, including the formation of the rift system that is the cradle of humankind, are preserved in sedimentary rocks. Our collaborative work will tease out how tectonics and climate come together to drive evolution.”
And they could add all kinds of localized environmental changes as the forces that “come together to drive evolution”.
Human evolution: Neanderthal Y chromosome
by David Turell , Tuesday, September 29, 2020, 15:10 (1514 days ago) @ dhw
DAVID: No need to change or repeat my known answers. God designs what is needed for each new advance, anticipating new abilities and activities.
dhw: Understood. So now will you please answer my questions: Did your God preprogramme upright walking semi-apes, or did he step in and do a dabble on the legs, leaving chests and brains alone until the next dabble? Why do you think he would preprogramme or dabble these interim changes? What purpose would they have served unless it was to meet some new requirement?
Your view of my God is very askew. New requirements do not drive evolution. God runs evolution I view Him as advancing evolution from one earlier stage to the next more complex stage on the way to humans. Of course they are adaptable to changing conditions, but they don't self-adapt to speciation. History tells us how God did it. Each advance allows new activities which have new requirements within themselves that may require some adaptation. The difference is I see God pushing evolution forward and you see various circumstances pulling it forward. Pure Darwin.
dhw: ...Nor have you responded to my argument concerning isolated populations.DAVID: Answered several days ago in a comment you removed in your next reply:
Saturday, September 26, 2020, 11:22 (2 days ago) @ David Turell
QUOTE: Neanderthals had smaller populations than moderns, and small populations tend to accumulate deleterious mutations, especially on the X and Y sex chromosomes. (David’s bold)dhw: That had nothing to do with the exchange I’m talking about, which I reproduce below. You challenged my proposal – in line with Gould’s theory – that isolated groups of pre-humans would have taken to life on the ground while the rest of their species lived happily ever after in the trees.
The grounded pre-humans would have had to make a group decision to do that. I can't imagine a whole group of apes suddenly deciding to do that. My God led the way.
DAVID: But first all were groups of apes using trees. Do trees suddenly disappear over night? No, it was gradual, which means the ape groups could easily followed the retreat of the trees. Your natural theory, as usual, has huge holes.dhw: You have just agreed that isolated populations cause large evolutionary advances. An isolated group of apes would be isolated for a reason. They would not “easily follow” anything that took them out of their isolation. But of course this is all speculation. Maybe tree life wasn't providing enough food for our little group of explorers. Or maybe there was too much competition.
dhw: May I presume from your silence that you now accept this as a possible explanation for some apes changing and others staying the same?
This degree of wandering speculation looks again for a natural progression, and I have idea what part to accept. Remember I think God is the driver.
QUOTE UNDER “Human evolution A whale at altitude in Kenya”): “Here, uniquely, the region’s geologic and climate histories, including the formation of the rift system that is the cradle of humankind, are preserved in sedimentary rocks. Our collaborative work will tease out how tectonics and climate come together to drive evolution.”dhw: And they could add all kinds of localized environmental changes as the forces that “come together to drive evolution”.
Again, your desire for natural causes.
Human evolution: Neanderthal Y chromosome
DAVID: God designs what is needed for each new advance, anticipating new abilities and activities.
dhw: Understood. So now will you please answer my questions: Did your God preprogramme upright walking semi-apes, or did he step in and do a dabble on the legs, leaving chests and brains alone until the next dabble? Why do you think he would preprogramme or dabble these interim changes? What purpose would they have served unless it was to meet some new requirement?
DAVID: Your view of my God is very askew. New requirements do not drive evolution. God runs evolution I view Him as advancing evolution from one earlier stage to the next more complex stage on the way to humans. Of course they are adaptable to changing conditions, but they don't self-adapt to speciation. History tells us how God did it. Each advance allows new activities which have new requirements within themselves that may require some adaptation. The difference is I see God pushing evolution forward and you see various circumstances pulling it forward. Pure Darwin.
All of this confirms the view of God that I am challenging! You have him changing different parts of the pre-sapiens anatomy at different times, either by preprogramming or by dabbling, in ANTICIPATION of new abilities and activities. And yet you accept that organisms adapt to changing conditions!!! That means they change their structure IN RESPONSE TO and not in anticipation of new requirements. This is why I keep badgering you to agree that (theistic version) your God must have given organisms (cell communities) a mechanism enabling them to change their structure without his intervention. Perhaps your reluctance to answer is due to your awareness that the same mechanism could be responsible for the various changes in the human anatomy and for speciation in general.
dhw: You challenged my proposal – in line with Gould’s theory – that isolated groups of pre-humans would have taken to life on the ground while the rest of their species lived happily ever after in the trees.
DAVID: The grounded pre-humans would have had to make a group decision to do that. I can't imagine a whole group of apes suddenly deciding to do that. My God led the way.
Most groups have leaders who take decisions, but in any case, if the whole group of apes was under threat from changing conditions, they’d have to be pretty daft not to look for ways to survive! But I love the image of a group of daft apes sitting there wondering what do in order to save themselves, and along comes God: “Follow me, guys!”
QUOTE (under “Human evolution A whale at altitude in Kenya”): “Here, uniquely, the region’s geologic and climate histories, including the formation of the rift system that is the cradle of humankind, are preserved in sedimentary rocks. Our collaborative work will tease out how tectonics and climate come together to drive evolution.”
dhw: And they could add all kinds of localized environmental changes as the forces that “come together to drive evolution”.
DAVID: Again, your desire for natural causes.
This is your new mantra. What is wrong with the idea that there is a reason for organisms to change, and that they MUST respond (adapt) to changing conditions if they are to survive? And that by extension, they might also find new ways (innovation leading to speciation) to exploit changing conditions? You have said that by “natural” you mean without God. But you know perfectly well that what I am proposing does not exclude God, as he may be the maker of the mechanism which allows them to adapt and/or innovate.
Human evolution: Neanderthal Y chromosome
by David Turell , Wednesday, September 30, 2020, 15:33 (1513 days ago) @ dhw
DAVID: Your view of my God is very askew. New requirements do not drive evolution. God runs evolution I view Him as advancing evolution from one earlier stage to the next more complex stage on the way to humans. Of course they are adaptable to changing conditions, but they don't self-adapt to speciation. History tells us how God did it. Each advance allows new activities which have new requirements within themselves that may require some adaptation. The difference is I see God pushing evolution forward and you see various circumstances pulling it forward. Pure Darwin.
dhw: All of this confirms the view of God that I am challenging! You have him changing different parts of the pre-sapiens anatomy at different times, either by preprogramming or by dabbling, in ANTICIPATION of new abilities and activities. And yet you accept that organisms adapt to changing conditions!!! That means they change their structure IN RESPONSE TO and not in anticipation of new requirements. This is why I keep badgering you to agree that (theistic version) your God must have given organisms (cell communities) a mechanism enabling them to change their structure without his intervention. Perhaps your reluctance to answer is due to your awareness that the same mechanism could be responsible for the various changes in the human anatomy and for speciation in general.
Of course organisms adapt to current changing conditions. Epigenetic changes are survival changes so the organisms live the best way they can. We have both agreed we don't know why speciation occurs. I believe God speciates. He has not given the ability of speciation to organisms. The new complexities require design by God.
dhw: You challenged my proposal – in line with Gould’s theory – that isolated groups of pre-humans would have taken to life on the ground while the rest of their species lived happily ever after in the trees.DAVID: The grounded pre-humans would have had to make a group decision to do that. I can't imagine a whole group of apes suddenly deciding to do that. My God led the way.
dhw: Most groups have leaders who take decisions, but in any case, if the whole group of apes was under threat from changing conditions, they’d have to be pretty daft not to look for ways to survive! But I love the image of a group of daft apes sitting there wondering what do in order to save themselves, and along comes God: “Follow me, guys!”
Yes, cute.
QUOTE (under “Human evolution A whale at altitude in Kenya”): “Here, uniquely, the region’s geologic and climate histories, including the formation of the rift system that is the cradle of humankind, are preserved in sedimentary rocks. Our collaborative work will tease out how tectonics and climate come together to drive evolution.”dhw: And they could add all kinds of localized environmental changes as the forces that “come together to drive evolution”.
DAVID: Again, your desire for natural causes.
dhw: This is your new mantra. What is wrong with the idea that there is a reason for organisms to change, and that they MUST respond (adapt) to changing conditions if they are to survive? And that by extension, they might also find new ways (innovation leading to speciation) to exploit changing conditions? You have said that by “natural” you mean without God. But you know perfectly well that what I am proposing does not exclude God, as he may be the maker of the mechanism which allows them to adapt and/or innovate.
What is the point of a God-given mechanism only partially under his control? This issue strongly involves each of our views of Gods personality. I see Him as staying tight control, fully purposeful. Why is it important to you to view a God with partial control?
Human evolution: menstruation
by David Turell , Saturday, October 03, 2020, 14:39 (1510 days ago) @ David Turell
Very few other animals do this:
https://science.sciencemag.org/content/370/6512/71.5?utm_campaign=ec_sci_2020-10-01&...
"The endometrium, which lines the uterus, is a distinct tissue that is capable of monthly remodeling, shedding, and regeneration. Other than humans, very few species exhibit a similar menstrual cycle. Given the importance of the endometrium to fertility and women's health, Wang et al. undertook single-cell transcriptomic characterization of the endometrium across the menstrual cycle from 19 healthy donors. The authors defined four phases across the cycle and characterized the window of implantation and accompanying changes in gene expression in the epithelia. They also discovered the presence of ciliated epithelium and characterized how these cells and six other cell types change over the course of the cycle. These high-resolution data provide important insights into female physiology and have numerous applications in fertility and endometrial biology."
Comment: Another way we are different
Human evolution: using fire to improve stone tools
by David Turell , Monday, October 05, 2020, 18:05 (1508 days ago) @ David Turell
In a cave in Israel the stone tools were studied:
https://www.jpost.com/archaeology/israeli-study-finds-ancient-hominins-used-fire-to-mak...
"In an article that appeared Monday in Nature Human Behaviour, researchers at the Weizmann Institute of Science in Rehovot detail how they employed cutting-edge technologies to take a fresh look at a collection of ancient stone tools. Their results suggest that the early humans who made them may have had a good understanding of the effects of heating the stone before flaking it into blades and may even have used a variety of temperatures to create different types of tools.
"Qesem Cave, a site in central Israel, was excavated by Prof. Avi Gopher and colleagues at Tel Aviv University, and the findings from the cave have been dated to between 420,000 and 200,000 years ago – the Lower Paleolithic period – and it is assigned to the unique Acheulo-Yabrudian Cultural Complex.
"The ancient hominins, a group that includes modern humans as well as extinct human species, who lived in Qesem Cave, left behind tens of thousands of stone tools. These tools are mainly made of flint, a material which is readily available all over the country, and they were produced in a process called knapping, a process that uses another rock or tool to chip off pieces, honing a sharp edge.
***
"They compared three different types of flint artifacts, and revealed three unique temperature ranges, one for each kind. The first type, which the scientists call “pot-lids,” were small, nicked and chipped shards, and the analysis showed they had been exposed to fire hot enough to cause pieces of the flint to fly off on their own accord. That told the team their analysis was on the right track, as it had been suggested in other studies that very high heat – up to 600 degrees Celsius – had been suggested, created the nicks and chips. The second type of pieces are known as flakes and the third are the blades, larger, knife-like tools with one long sharp edge and a facing, thicker edge where they can be held. Flakes, essentially smaller cutting tools than the blades, had been treated at a relatively large range of temperatures while the blades had been heated to lower temperatures and the temperature range they had undergone was much smaller. In other words, it appeared as though the cave’s inhabitants had intentionally used different heat treatments to create different tools.
“'We can’t know how they taught others the skill of toolmaking, what experience led them to heat the raw flint to different temperatures, or how they managed to control the process, but the fact that the longer blades are consistently heated in a different way than the other pieces does point to an intent,” said Natalio.
"Pinkas said, “And that is technology, as surely as our cell phones and computers are technology. It enabled our ancestors to survive and thrive.'”
Comment: It can not be known exactly when the inventive technique developed, pre-sapiens or by sapiens. but it shows a marked level of clever thought and experimentation.
Human evolution: migration changes eye color
by David Turell , Monday, October 05, 2020, 20:57 (1508 days ago) @ David Turell
Moving out of Africa to Europe made eyes turn blue, among other colors:
https://www.realclearscience.com/blog/2020/10/01/ancient_humans_eyes_were_nearly_black_...
"The human eye's hallmark trait is its medley of colors. The iris, which surrounds the pupil, can appear blue, green, gray, hazel, brown, and even red. Differences in levels of the pigment melanin primarily account for the varying hues – more melanin renders the eyes darker, while less leaves eyes reflecting light blue. How much melanin dwells within the iris depends on the expression of around a dozen different genes, and perhaps more. The two most important by far are OCA2 and HERC2. OCA2 produces a protein that controls the maturation of melanin-producing melanosomes. HERC2 controls the expression of OCA2.
"When humans arose in the horn of Africa at least a quarter of a million years ago, human eyes were extremely dark brown or nearly black. That's because OCA2 was expressed at high levels, in turn leading to the production of more melanin, which colored skin dark brown and, as a side effect, darkened irises. Brown skin is less likely to be sunburned or to develop skin cancer, benefits which served humans well in Central Africa's sunny, equatorial climate.
***
"In Northern Europe, where sunlight can be a scarce commodity in winter, lighter skin tones became advantageous, as they allow for more vitamin D absorption from sunlight. This meant less melanin in the body, which permitted eye color to diversify as other genes that more subtly affected eye color mutated, their influence becoming more apparent.
"Blue eyes, for example, are extremely common in northern Europe after rising to prominence roughly 7,000 years ago. Besides evoking chilling thoughts of white walkers from Game of Thrones, blue eyes may actually help regulate circadian rhythms, molecular geneticist Associate Professor Rick Sturm of the University of Queensland told ABC Science. This makes them particularly useful in higher latitudes, where hours of sunlight differ drastically with the seasons."
Comment: Darwin- based writing always points out purposeful adaptations with the assumption they just happened. They sure look directed to me.
Human evolution: extinction of earlier forms
by David Turell , Thursday, October 15, 2020, 19:11 (1498 days ago) @ David Turell
Why did some of the early branches disappear:
https://phys.org/news/2020-10-climate-drove-early-human-species.html
"'Our findings show that despite technological innovations including the use of fire and refined stone tools, the formation of complex social networks, and—in the case of Neanderthals—even the production of glued spear points, fitted clothes, and a good amount of cultural and genetic exchange with Homo sapiens, past Homo species could not survive intense climate change," says Pasquale Raia of Università di Napoli Federico II in Napoli, Italy. "They tried hard; they made for the warmest places in reach as the climate got cold, but at the end of the day, that wasn't enough."
"To shed light on past extinctions of Homo species including H. habilis, H. ergaster, H. erectus, H. heidelbergensis, H. neanderthalensis, and H. sapiens, the researchers relied on a high-resolution past climate emulator, which provides temperature, rainfall, and other data over the last 5 million years. They also looked to an extensive fossil database spanning more than 2,750 archaeological records to model the evolution of Homo species' climatic niche over time. The goal was to understand the climate preferences of those early humans and how they reacted to changes in climate.
"Their studies offer robust evidence that three Homo species—H. erectus, H. heidelbergensis, and H. neanderthalensis—lost a significant portion of their climatic niche just before going extinct. They report that this reduction coincided with sharp, unfavorable changes in the global climate. In the case of Neanderthals, things were likely made even worse by competition with H. sapiens.
"'We were surprised by the regularity of the effect of climate change," Raia says. "It was crystal clear, for the extinct species and for them only, that climatic conditions were just too extreme just before extinction and only in that particular moment.'"
Comment: The last ice age technically ended 11,700 years ago. This means the Earth was quite cold while these forms of homo tried to survive, obviouslty we had the brains to do it.
Human evolution: 325,000 year old environmental changes
by David Turell , Wednesday, October 21, 2020, 20:35 (1492 days ago) @ David Turell
New studies in Ethiopia from deep earthen core samples:
https://phys.org/news/2020-10-turbulent-era-human-behavior-years.html
" For hundreds of thousands of years, early humans in the East African Rift Valley could expect certain things of their environment. Freshwater lakes in the region ensured a reliable source of water, and large grazing herbivores roamed the grasslands. Then, around 400,000 years ago, things changed. The environment became less predictable, and human ancestors faced new sources of instability and uncertainty that challenged their previous long-standing way of life.
" The first analysis of a new sedimentary drill core representing 1 million years of environmental history in the East African Rift Valley shows that at the same time early humans were abandoning old tools in favor of more sophisticated technology and broadening their trade networks, their landscape was experiencing frequent fluctuations in vegetation and water supply that made resources less reliably available. The findings suggest that instability in their surrounding climate, land and ecosystem was a key driver in the development of new traits and behaviors underpinning human adaptability.
***
"...early humans at Olorgesailie relied on the same tools, stone handaxes, for 700,000 years. Their way of life during this period was remarkably stable, with no major changes in their behaviors and strategies for survival. Then, beginning around 320,000 years ago, people living there entered the Middle Stone Age, crafting smaller, more sophisticated weapons, including projectiles. At the same time, they began to trade resources with distant groups and to use coloring materials, suggesting symbolic communication. All these changes were a significant departure from their previous lifestyle, likely helping early humans cope with their newly variable landscape, Potts said.
***
While some scientists have proposed that climate fluctuations alone may have driven humans to evolve this remarkable quality of adaptability, the new study indicates the picture is more complicated than that. Instead, the team's analysis shows that climate variability is but one of several intertwined environmental factors that drove the cultural shift they described in 2018. The new analysis reveals how a changing climate along with new land faults introduced by tectonic activity and ecological disruptions in the vegetation and fauna all came together to drive disruptions that made technological innovation, trading resources and symbolic communication¬—three key factors in adaptability—beneficial for early humans in this region.
***
"They found that after a long period of stability, the environment in this part of Africa became more variable around 400,000 years ago, when tectonic activity fragmented the landscape. By integrating information from the drill core with knowledge gleaned from fossils and archeological artifacts, they determined that the entire ecosystem evolved in response.
"The team's analysis suggests that as parts of the grassy plains in the region were fragmented along fault lines due to tectonic activity, small basins formed. These areas were more sensitive to changes in rainfall than the larger lake basins that had been there before. Elevated terrain also allowed water runoff from high ground to contribute to the formation and drying out of lakes. These changes occurred during a period when precipitation had become more variable, leading to frequent and dramatic fluctuations in water supply.
"With the fluctuations, a broader set of ecological changes also took place. The team found that vegetation in the region also changed repeatedly, shifting between grassy plains and wooded areas. Meanwhile, large grazing herbivores, which no longer had large tracts of grass to feed on, began to die out and were replaced by smaller mammals with more diverse diets.
"'There was a massive change in the animal fauna during the time period when we see early human behavior changing," Potts said. "The animals also influenced the landscape through the kinds of plants that they ate. Then with humans in the mix, and some of their innovations like projectile weapons, they also may have affected the fauna. It's a whole ecosystem changing, with humans as part of it.'"
Comment: With big-brained H. sapiens dated at 315,000 years ago in Morocco the ability to adapt had to be improved. Darwinists, like the authors, assume it is all adaptability changes, but the appearance of the big brain was undoubtedly was the main factor in human response and inventiveness.
Human evolution: erectus made barbed bone points
by David Turell , Thursday, October 22, 2020, 23:11 (1491 days ago) @ David Turell
A new study from the Olduvai gorge:
https://www.sciencenews.org/article/homo-erectus-not-humans-invented-barbed-bone-point-...
"A type of bone tool generally thought to have been invented by Stone Age humans got its start among hominids that lived hundreds of thousands of years before Homo sapiens evolved, a new study concludes.
"A set of 52 previously excavated but little-studied animal bones from East Africa’s Olduvai Gorge includes the world’s oldest known barbed bone point, an implement probably crafted by now-extinct Homo erectus at least 800,000 years ago, researchers say. Made from a piece of a large animal’s rib, the artifact features three curved barbs and a carved tip, the team reports in the November Journal of Human Evolution.
"Among the Olduvai bones, biological anthropologist Michael Pante of Colorado State University in Fort Collins and colleagues identified five other tools from more than 800,000 years ago as probable choppers, hammering tools or hammering platforms.
***
"This find and four of the other bone implements date to at least 800,000 years ago, based on their original positions below Olduvai sediment that records a known reversal of Earth’s magnetic field about 781,000 years ago. Another bone artifact dates to roughly 1.7 million years ago, the researchers say.
“The Olduvai point implicates H. erectus as the inventor of barbed bone point technology,” Pante says, because stone tools previously excavated in the same Olduvai Gorge sediment resemble those that have been found at other African sites with H. erectus fossils.
***
"Along with bone toolmaking, a series of critical behavioral advances in hominids occurred before the emergence of H. sapiens around 300,000 years ago. These developments include the invention of stone tools (SN: 6/3/19), controlled fire use (SN: 4/2/12) and the ability to survive in new environments (SN: 11/29/18). Exploiting bone to make tools such as barbed points would have aided ancient Homo groups migrating through unfamiliar regions where locations of stone sources were unknown, Pante suspects."
Comment: Erectus were bright folks shown by what they learned to invent. They just lacked the 200 cc of prefrontal and frontal lobes for advanced conceptualization.
Human evolution: newborn pre-wired to see words
by David Turell , Thursday, October 22, 2020, 23:31 (1491 days ago) @ David Turell
A new finding using newborn MRI compared to adult:
https://medicalxpress.com/news/2020-10-humans-born-brains-prewired-words.html
"Humans are born with a part of the brain that is prewired to be receptive to seeing words and letters, setting the stage at birth for people to learn how to read, a new study suggests.
"Analyzing brain scans of newborns, researchers found that this part of the brain—called the 'visual word form area' (VWFA) - is connected to the language network of the brain.
"'That makes it fertile ground to develop a sensitivity to visual words—even before any exposure to language," said Zeynep Saygin,
"The VWFA is specialized for reading only in literate individuals. Some researchers had hypothesized that the pre-reading VWFA starts out being no different than other parts of the visual cortex that are sensitive to seeing faces, scenes or other objects, and only becomes selective to words and letters as children learn to read or at least as they learn language.
"'We found that isn't true. Even at birth, the VWFA is more connected functionally to the language network of the brain than it is to other areas," Saygin said. "It is an incredibly exciting finding."
***
"'The VWFA is specialized to see words even before we're exposed to them," Saygin said.
"'It's interesting to think about how and why our brains develop functional modules that are sensitive to specific things like faces, objects, and words," said Li, who is lead author of the study.
"'Our study really emphasized the role of already having brain connections at birth to help develop functional specialization, even for an experience-dependent category like reading.'"
Comment: WE have no way of knowing just how this special set of connections developed or when. Knowing spoken language developed first and reading later, then two possibilities are it already existed when sapiens arrived, or it developed from preexisting modules in the brain by plasticity.
Human evolution: newborn pre-wired to see words II
by David Turell , Friday, October 23, 2020, 21:00 (1490 days ago) @ David Turell
David: A new finding using newborn MRI compared to adult:
https://medicalxpress.com/news/2020-10-humans-born-brains-prewired-words.html
"Humans are born with a part of the brain that is prewired to be receptive to seeing words and letters, setting the stage at birth for people to learn how to read, a new study suggests."Analyzing brain scans of newborns, researchers found that this part of the brain—called the 'visual word form area' (VWFA) - is connected to the language network of the brain.
"'That makes it fertile ground to develop a sensitivity to visual words—even before any exposure to language," said Zeynep Saygin,
"The VWFA is specialized for reading only in literate individuals. Some researchers had hypothesized that the pre-reading VWFA starts out being no different than other parts of the visual cortex that are sensitive to seeing faces, scenes or other objects, and only becomes selective to words and letters as children learn to read or at least as they learn language.
"'We found that isn't true. Even at birth, the VWFA is more connected functionally to the language network of the brain than it is to other areas," Saygin said. "It is an incredibly exciting finding."
***
"'The VWFA is specialized to see words even before we're exposed to them," Saygin said.
"'It's interesting to think about how and why our brains develop functional modules that are sensitive to specific things like faces, objects, and words," said Li, who is lead author of the study.
"'Our study really emphasized the role of already having brain connections at birth to help develop functional specialization, even for an experience-dependent category like reading.'"
David: Comment: WE have no way of knowing just how this special set of connections developed or when. Knowing spoken language developed first and reading later, then two possibilities are it already existed when sapiens arrived, or it developed from preexisting modules in the brain by plasticity.
An afterthought: it sure looks like God pre-planning for expected human activities involving language, reading and writing.
Human evolution: the evolution of emotions
by David Turell , Saturday, November 07, 2020, 19:01 (1475 days ago) @ David Turell
A study involving our brain to relate our emotions to the past:
https://aeon.co/essays/human-culture-and-cognition-evolved-through-the-emotions?utm_sou...
"The field of affective neuroscience isolates emotional brain systems (largely in regions of the brain that we share with other mammals) that undergird adaptive behaviours in vertebrates. With the help of neuroscientific and behavioural research, we are beginning to appreciate how the ancestral mammal brain is alive and well inside our higher neocortical systems.
***
"Some historians and anthropologists argue that we learn our emotions from our cultural experience, and that they are thus constituted by very particular circumstances. If that’s the case, then our argument for the importance of emotional wellsprings in the evolution (and therefore the nature) of the human mind comes unmoored. So is the basic emotional structure of the mind a universal, biological fact?
***
"Affective science posits a layered brain that is plastic enough to account for diversity, without having to throw out the biology of emotions. The reason why we classify a handful of behaviours, expressions and feelings as ‘anger’ is because an identifiable physiological pattern underlies them, and such patterns evolved in mammal brains to aid their survival. Brain scans reveal some diversity of neural pathways during anger or lust, for example, but not enough diversity to confound the density distributions of the data. The higher (or tertiary) level of language, culture and conscious deliberation does have an effect on how our emotions are manifested, but the range of possible emotional states and interpretations is fairly strict and limited.
***
"Crucially, over the past three decades, affective neuroscientists have engaged specialised technology to diligently map distinct neural pathways for the most basic, primary emotions. Extensive research on the amygdala, for example, reveals that fear has a clear brain signature. And precise localised electrical stimulation of the brain reveals specific affective and behavioural responses in animals.
***
"Rather than seeking linguistic confirmation that a creature is indeed experiencing an emotion, observation of its behaviour proves more revealing. The clear implication of tying the experience of emotions to the possession of concepts is that all animals and babies do not have emotions because they lack language. This seems remarkably inconsistent with evidence from animal studies, developmental psychology, as well as common sense.
***
"For at least 200 million years, the emotional brain has been under construction. By comparison, the focus of the cognitive approach, the expansion of the ‘rational’ neocortex around 1.8 million years ago is a latecomer on the scene, and the development of our language-symbol system is younger still. As a suite of adaptive tools, the emotions have been at work substantially longer than rational cognition, so it makes little biological sense to think about the mind as an idealised rational cost-benefit computer, projected into deep time.
"A sufficient account of the evolution of mind must go deeper than our power of propositional thinking – our rarefied ability to manipulate linguistic representations. We will have to understand a much older capacity – the power to feel and respond appropriately. We need to think about consciousness itself as an archaeologist thinks about layers of sedimentary strata. At the lower layers, we have basic drives that prod us (and other animals) out into the environment for the exploitation of resources. Thirst, lust, fear and so on are triggers in evolutionarily earlier regions of the brain that stimulate vertebrates toward satisfaction and a return to homeostasis (physiological balance). At the lowest primary level, fear, for example, is radical. Under threat, the fearful animal voids its bowels, and a surge of activity in the amygdala and hypothalamus readies it for defence or escape.
***
"It is probably most accurate to say that primary and secondary emotions have phenomenal consciousness (experiential feeling), but lack access consciousness (the ability to rationally access, manipulate and reflect upon emotions).
***
"Humans would not be such masterful cooperators, especially in non-kin social groups, if they did not undergo some significant emotional domestication that sculpted our motivations and desires towards prosocial coexistence. As the primatologist Richard Wrangham argues in The Goodness Paradox (2019), compared with our primate cousins, humans domesticated themselves by significantly reducing their reactive aggression. Besides anger, we think that similar selective processes of cultural evolution sculpted other emotions such as lust and care over evolutionary time."
Comment: There is lots of truth here. Our enormous cortex is built upon an ancient layer of animal feelings in brains. On the ranch we can see animal emotions all the time.
Human evolution: how as family we differ
by David Turell , Monday, November 09, 2020, 14:18 (1473 days ago) @ David Turell
The relationship of infant and elderly need for help:
https://aeon.co/essays/why-childhood-and-old-age-are-key-to-our-human-capacities?utm_so...
"Human beings need special care while we are young and when we become old. The 2020 pandemic has made this vivid: millions of people across the world have taken care of children at home, and millions more have tried to care for grandparents, even when they couldn’t be physically close to them. COVID-19 has reminded us how much we need to take care of the young and the old. But it’s also reminded us how much we care for and about them, and how important the relations between the generations are. I have missed restaurants and theatres and haircuts, but I would easily give them all up to be able to hug my grandchildren without fear. And there is something remarkably moving about the way that young people transformed their lives to protect older ones.
"But this raises a puzzling scientific paradox. We know that biological creatures are shaped by the forces of evolution, which selects organisms based on their fitness – that is, their ability to survive and reproduce in a particular environment. So why has it allowed us to be so vulnerable and helpless for long stretches of our lives? Why do the strong, able humans in their prime of life put so much time and energy into caring for those who are not yet, or no longer, so productive? New research argues that those vulnerabilities are intimately related to some of our greatest human strengths – our capacities for learning, cooperation and culture.
***
"On an evolutionary timescale, Homo sapiens emerged only quite recently. Yet in that short time, we have evolved a particularly weird life history, with a much longer childhood and old age than other animals. In particular, we’re very different from our closest primate relatives. By at least age seven, chimpanzees provide as much food as they consume, and they rarely live past 50 – there’s no chimp equivalent of human menopause. Even in forager cultures, where growing up is accelerated, children aren’t self-sufficient until they’re at least 15. What’s more, even in communities without access to modern medicine, if you make it past childhood you might well live into your 70s. We live some 20 years longer than chimpanzees and, except for a few whale species, particularly orcas, we are the only mammals who systematically outlive our fertility.
***
"These changes in life history evolved at the same time as dramatic changes in human brains and minds. We have many more neurons than other primates. And we developed striking abilities to learn and invent, communicate and cooperate, and create and transmit culture. New analyses of fossil records show that humans evolved their large brains and distinctive capacities in parallel with their longer childhood and old age. Our unique human vulnerabilities somehow emerged in concert with our unique human strengths. Just how are these two kinds of changes related? Researchers from biology, psychology and anthropology have recently begun to work together in order to answer these questions – answers that help to explain what makes us distinctively human.
***
"For humans, the elders at the other end of the lifespan appear to be a particularly important source of care, and might have played a crucial role in human evolution. The anthropologist Kristen Hawkes has called this ‘the grandmother hypothesis’, and has shown that, in forager cultures, post-menopausal grandmothers are a crucial resource, especially for toddlers. Since human mothers have babies at relatively short intervals, a mum might be nursing a new infant even while the older sibling still needs lots of attention – grandmothers can take over after a nursing infant becomes an equally vulnerable but even more demanding toddler.
***
"Traditionally, anthropologists argued that humans cooperated in order to hunt more effectively. But recent studies of forager cultures suggest that the benefits of hunting might be exaggerated – actually the grandmothers quietly digging up roots and tubers potentially provided many more calories than those mighty hunters.
***
"Orcas are among the only other mammals with post-menopausal grandmothers. Orca children
and grandchildren stay close to the older females, even after they mature themselves.
***
"...childhood and old age – those vulnerable, unproductive periods of our lives – turn out, biologically, to be the key to many of our most valuable, deeply human capacities. They nurture and facilitate our exploration and creativity, cooperation, coordination and culture, learning and teaching."
Comment: We are very different, and the author blames Natural Selection for our arrival with no mention of why the brain expanded like it did. Orcas and us, my bold. Why?
Human evolution: new Paranthropus robustus skull find
by David Turell , Monday, November 09, 2020, 23:09 (1473 days ago) @ David Turell
A very early hominin, two million years old:
https://cosmosmagazine.com/nature/evolution/well-preserved-addition-to-the-evolution-st...
"A two-million-year-old hominin skull has been uncovered in a South African cave, providing fresh insight into the microevolution of our ancient cousins.
"The skull is the earliest-known and best-preserved specimen of Paranthropus robustus: a short, robust, upright hominin that is thought to have gone extinct around a million years ago. The species possessed distinctive large molars and powerful jaws that would have been useful for eating tough vegetation, seeds and roots.
***
“'The DNH 155 cranium shows the beginning of a very successful lineage that existed in South Africa for a million years,” says La Trobe’s Andy Herries, a co-author.
***
"Since their discovery in 1992, the Drimolen caves have acted as a window into early hominin evolution. In 2018 they revealed some of the world’s oldest bone tools, and earlier in 2020, a research team led by Herries uncovered the earliest-known skull of Homo erectus, a much closer relative of modern humans.
"The species existed from around two million to 100,000 years ago, arising at around the same time as Paranthropus robustus. The Drimolen caves also previously yielded several other P. robustus skulls, providing evidence for their co-existence with H. erectus.
***
"But the two species were vastly different. While H. erectus had relatively large brains and small teeth, P. robustus were small-brained and large-toothed. According to co-author Angeline Leece, also from La Trobe, the two represent “divergent evolutionary experiments”.
"This new study presents another P. robustus cranium – dubbed DNH 155 – that dates back further, to approximately 2.04-1.95 million years ago.
***
“The DNH 155 male fossil from Drimolen is most similar to female specimens from the same site, whereas Paranthropus robustus specimens from other sites are appreciably different,” he says.
"The specimen also suggests that the species evolved their distinctive chewing adaptations in incremental steps over hundreds of thousands of years, leading the team to argue that this is the first high-resolution evidence of microevolution in an early hominin species.
"Leece explains that, over time, “Paranthropus robustus likely evolved to generate and withstand higher forces produced during biting and chewing food that was hard or mechanically challenging to process with their jaws and teeth – such as tubers.”
"These adaptations are believed to have taken place during a period of environmental change, when climate records indicate that the region was drying out. The increasingly arid conditions led to the extinction of several mammal species and may have placed hominins under dietary stress."
Comment: This adds to the story and tells us that many different types of hominins coexisted, as more advanced forms developed, and also notes the forms modified as needs changed. Was this epigenetics in action, but not speciation. since it appears within the same species?
Human evolution: how as family we differ
DAVID: The relationship of infant and elderly need for help:
https://aeon.co/essays/why-childhood-and-old-age-are-key-to-our-human-capacities?utm_so...
QUOTE: "Orcas are among the only other mammals with post-menopausal grandmothers. Orca children and grandchildren stay close to the older females, even after they mature themselves. (David’s bold)
QUOTE: "...childhood and old age – those vulnerable, unproductive periods of our lives – turn out, biologically, to be the key to many of our most valuable, deeply human capacities. They nurture and facilitate our exploration and creativity, cooperation, coordination and culture, learning and teaching."
DAVID: We are very different, and the author blames Natural Selection for our arrival with no mention of why the brain expanded like it did. Orcas and us, my bold. Why?
We have covered the subject of brain expansion elsewhere. I don’t know why you’ve bolded the reference to orcas, but it might be interesting to know why you think your God singled them out. I don’t honestly see what the author is trying to prove. In animal families and societies, the older generation teaches the younger generation, nurturing and facilitating their exploration, cooperation, coordination, learning and teaching. (I’ve left out our creativity and our culture, as they vastly exceed the range of anything found in the animal world.) Most animals live far shorter lives than we do, and they certainly have far less to teach/learn, but the basic principle is the same. Animal young are just as vulnerable as human young, and there is nothing unique in parental care. We and orcas may be the only mammals that outlive our fertility, but what does that prove? Most of our fellow mammals can go on being parents until they die (usually much earlier than we do) – and they go on teaching their young.
Human evolution: how as family we differ
by David Turell , Tuesday, November 10, 2020, 15:36 (1472 days ago) @ dhw
DAVID: The relationship of infant and elderly need for help:
https://aeon.co/essays/why-childhood-and-old-age-are-key-to-our-human-capacities?utm_so...QUOTE: "Orcas are among the only other mammals with post-menopausal grandmothers. Orca children and grandchildren stay close to the older females, even after they mature themselves. (David’s bold)
QUOTE: "...childhood and old age – those vulnerable, unproductive periods of our lives – turn out, biologically, to be the key to many of our most valuable, deeply human capacities. They nurture and facilitate our exploration and creativity, cooperation, coordination and culture, learning and teaching."
DAVID: We are very different, and the author blames Natural Selection for our arrival with no mention of why the brain expanded like it did. Orcas and us, my bold. Why?
dhw: We have covered the subject of brain expansion elsewhere. I don’t know why you’ve bolded the reference to orcas, but it might be interesting to know why you think your God singled them out. I don’t honestly see what the author is trying to prove. In animal families and societies, the older generation teaches the younger generation, nurturing and facilitating their exploration, cooperation, coordination, learning and teaching. (I’ve left out our creativity and our culture, as they vastly exceed the range of anything found in the animal world.) Most animals live far shorter lives than we do, and they certainly have far less to teach/learn, but the basic principle is the same. Animal young are just as vulnerable as human young, and there is nothing unique in parental care. We and orcas may be the only mammals that outlive our fertility, but what does that prove? Most of our fellow mammals can go on being parents until they die (usually much earlier than we do) – and they go on teaching their young.
The bold about Orcas was because it was a surprising fact. It is thought humans did not outlive their fertility before more modern times of the last 10,000 years. In horses, the young grow away from parents quickly and our Mother offspring pairs clearly showed no sense of recognition of each other after a year or so. As for early vulnerability, the human baby is rather uniquely helpless for a very long period compared to animals. I presented the article to emphasize our differences from the animal world.
Human evolution: burst of a bush of various types
by David Turell , Thursday, November 19, 2020, 00:25 (1463 days ago) @ David Turell
The hominin/homo forms burst on the scene and there is not one steady line of Darwinian development from simple to complex. There are branches in every direction, with simple and complex forms existing at the same time, with plenty of genetic material to show cross- breeding:
https://evolutionnews.org/2020/04/a-disappointing-decade-for-the-study-of-human-evolution/
"Some of these big discoveries actually turn out to be instances where the evidence for human evolution weakened, and the rest amount to slight revisions of previously held theories that don’t say much about the core tenets of paleoanthropology.
"it has shown that there were various sublineages of very modern human-like groups such as the Denisovans that have existed in the past million years. Though a novel and intriguing form of evidence, at present ancient DNA is essentially silent on two crucial tenets of evolutionary paleoanthropology: (1) the hypothesis that modern humans are descended from decidedly non-human, subhuman, or otherwise primitive species, and (2) the claim that these newly revealed “species of early humans” were substantially different from us. Yes we have Denisovan DNA, but at present for all we know the Denisovans were as human as we are.
"The second big discovery of the last decade was Homo naledi, which is also exciting because it represents a humungous cache of hominid fossils that adds a lot to our knowledge of the fossil record. Initially, news reports called Homo naledi a “human ancestor.” However in 2017 it was found that this species is only a few hundred thousand years old — 10 times too young to be considered as one of our evolutionary ancestors. This was a major bust for proponents of human evolution, as we reported here.
***
the third big find of the decade listed by Smithsonian is the discovery of a near-complete skull of Australopithecus anamensis last year, dated to about 3.8 million years old. Günter Bechly wrote an excellent review of this fossil find here at Evolution News. He pointed out that this skull allowed scientists to understand, for the first time, what the species A. anamensis actually looked like. However, its unexpectedly young age meant that it overlapped in time with its supposed descendants, the species A. afarensis. Science Daily quoted one of the scientists involved with the find as saying, “We used to think that A. anamensis gradually turned into A. afarensis over time.” But because of the age of the fossil, they no longer think this is the case.
***
"this example of an “ancestor-descendant sequence” can no longer be used because the A. anamensis skull discovered last year dates to 3.8 Ma, which is 100,000 years after the appearance of fossils of A. afarensis. A gradualistic transition is no longer feasible.
***
"Most importantly, [the paper] shows that despite the widely accepted hypothesis of anagenesis, A. afarensis did not appear as a result of phyletic transformation. It also shows that at least two related hominin species co-existed in eastern Africa around 3.8 Myr ago, further lending support to mid-Pliocene hominin diversity.”
***
"...in addition to A. anamensisi, A. afarensis, and Homo naledi, there’s a third example from the 2010s where the ages of hominid fossils posed problems for the standard evolutionary model. We also reported last year that a study of Australopithecus sediba and the hominin fossil record published in Science Advances concluded that there is less than a 0.1 percent chance that A. sediba could be a human ancestor. That’s because it postdates the appearance of its would-be descendants in the genus Homo by about 100,000 years."
Comment: There are more complications. we know Erectus lived until recently and where do the dwarf Homo floresiensis fit in since they also existed until recently. Sapiens co-exited with both Denisovans and Neanderthals, while some of these others were still around. Back to my same old question: apes and monkeys were living happily until we began our huge population growth. Darwin proposes stepwise change to aid survival. That is not the hominin historical evidence in the fossil record to date. Each new find seems to refute Darwin, and I'll bet that trend will continue. I view our history as bursting forward for no good demonstrable reason. I would suggest an agency is driving the process, an a gency we call God.
Human evolution: Ardipithecus ramidus.
by David Turell , Thursday, November 19, 2020, 23:26 (1463 days ago) @ David Turell
A very early hominin-like form happy to be in trees and on the ground:
https://www.sciencenews.org/article/evolutions-bad-girl
"First, White and his colleagues assert, Ardi’s unusual mix of apelike and monkeylike traits demolishes the long-standing assumption that today’s chimpanzees provide a reasonable model of either early hominids or the last common ancestor of people and chimps — an ancestor which some scientists suspect could even have been Ardi, if genetics-based estimates of when the split occurred are borne out.
"Second, the team concludes, Ardi trashes the idea that knuckle-walking or tree-hanging human ancestors evolved an upright gait to help them motor across wide ancient savannas. Her kind lived in wooded areas and split time between lumbering around on two legs hominid-style and cruising carefully along tree branches on grasping feet and the palms of the hands.
***
"In a third slap at scientific convention, Ardi fits a scenario in which a few closely related hominid lineages preceded the larger-brained Homo genus that emerged around 2.4 million years ago, White says. In contrast, many anthropologists think of hominid evolution as a bush composed of numerous lineages that, for the most part, died out.
***
"Ardi sports a peculiar skeletal medley that pushes chimps and gorillas out of the evolutionary spotlight, says anthropologist Owen Lovejoy, a member of White’s team. Ardi’s ancient remains indicate that the last common ancestor of humans and chimps must not have looked much like living chimps, as many researchers have assumed, asserts Lovejoy, of Kent State University in Ohio.
"Since a split 8 million years ago or so, chimps and gorillas have evolved along evolutionary paths that eventually produced specialized traits such as knuckle-walking, he says.
"In his opinion, Ardi indicates that a human-chimp ancestor had monkeylike limb proportions and feet, a flexible and unchimplike lower back, and an ability to move along tree branches on all fours, rather than swinging chimp-style from branch to branch and hanging by outstretched arms.
“'Ardipithecus, not living chimps, offers a remarkably good perspective on the last common ancestor,” he says. “We can’t modify the truth to make chimps more important.”
***
"Questions remain about whether Ardi had the build for regular upright walking — a clear marker of hominid status — or for primarily moving through trees, with occasional two-legged jaunts on the ground, adds anthropologist John Hawks of the University of Wisconsin–Madison.
"Consider Oreopithecus, an ape that lived on an island near Italy between 9 million and 7 million years ago. This creature possessed a pelvis, legs and feet that supported tree climbing as well as slow and somewhat stilted walking.
***
"If Ardipithecus adopted upright walking in a big way and was a precursor of the human lineage, Hawks posits, “it could be the first hominid or perhaps even the common ancestor of humans and chimps — if we take genetic studies seriously.” DNA analyses suggest that people and chimps split from a common ancestor between 5 million and 4.5 million years ago, around Ardi’s time."
Comment: This discussion of the earliest possible proto-hominins rules out the theory that tress disappeared and early forms had to learn to walk. These forms were prepared to do both at will. My point is I believe God designed them this way as a transitional form, not a change forced by natural changes to the environment as trees disappeared. Lucy was built the same way million of years later.
Human evolution: other partially upright ancient fossils
by David Turell , Friday, November 20, 2020, 04:40 (1462 days ago) @ David Turell
There are several:
https://www.sciencenews.org/article/evolutions-surprise-fossil-find-uproots-our-early-a...
"In a discovery that upends the study of human origins, scientists have unearthed remains of what they say is the earliest known member of the human evolutionary family. Investigators led by anthropologist Michel Brunet of the University of Poitiers in France estimate that the creature, officially dubbed Sahelanthropus tchadensis, lived between 7 million and 6 million years ago.
***
"First, a small braincase like that of living chimpanzees connects to a face and teeth resembling those of bigger-brained hominids dating to 1.75 million years ago, perhaps even early Homo specimens. No one had predicted that elements of later skulls–in particular, a short, relatively flat face, pronounced brow ridge, and small canine teeth–coexisted with a chimp-size brain in early hominids.
"Second, Brunet and his colleagues made their discovery in Chad, a central African nation located far from established fossil-hominid sites in eastern and southern Africa. It appears that, between 7 million and 5 million years ago, hominids evolved into a wider variety of lineages across a broader area than scientists had assumed, says anthropologist Bernard Wood of George Washington University in Washington, D.C.
“'This is an astonishing find,” remarks anthropologist Daniel Lieberman of Harvard University. “Hominid species in eastern and southern Africa appear to have been a small part of a more complicated evolutionary process.”
And another early transitional form:
https://www.sciencenews.org/article/earliest-ancestor-emerges-africa
"The fragmentary remains come from at least five individuals–in the genus Ardipithecus–who lived between 5.2 million and 5.8 million years ago, says anthropology graduate student Yohannes Haile-Selassie of the University of California, Berkeley.
***
"Much is also unknown about Ardipithecus‘ looks. The new finds consist of a partial jaw, a few teeth, several hand and foot bones, and pieces of an upper-arm bone and a collarbone. The bones are about the size of those from a modern common chimp. However, Ardipithecus displays dental features found in other hominids but not in any fossil or living ape.
"Moreover, the new finds include a toe bone shaped like those of Lucy and her kind. This constitutes “subtle but clear evidence” that Ardipithecus, like Australopithecus, walked on two legs, says anthropologist C. Owen Lovejoy of Kent (Ohio) State University, who independently examined the toe fossil. Ongoing studies of 4.4-million-year-old Ardipithecus fossils will further illuminate this hominid’s stance, Lovejoy says.
"The fossils were unearthed at sites in what is now a desert. When Ardipithecus lived there, the region contained a dense forest and had a cool, wet climate, according to studies led by Giday WoldeGabriel of Los Alamos (N.M.) National Laboratory." (my bold)
The new finds raise puzzling questions about why early hominids evolved an upright stance, Maclatchy adds. Researchers have often portrayed a two-legged stride as an adaptation to trekking across hot, grassy savannas. Yet Ardipithecus lived in shady forests where a hominid would have less need to stand up to dissipate heat or walk long distances.
Comment: There is no evidence (note the bold) that these guys were forced out of trees and had to change/adapt. The forests were there. I view this, as always, as change in preparation of what was to come. In other words, God in charge.
Human evolution: we are entirely improbable
by David Turell , Friday, January 15, 2021, 21:23 (1406 days ago) @ David Turell
A long discussion of the odds:
https://www.scientificamerican.com/article/our-improbable-existence-is-no-evidence-for-...
"...the universe we live in must be compatible with the existence of life. However, as scientists have studied the fundamental principles that govern our universe, they have discovered that the odds of a universe like ours being compatible with life are astronomically low. We can model what the universe would have looked like if its constants—the strength of gravity, the mass of an electron, the cosmological constant—had been slightly different. What has become clear is that, across a huge range of these constants, they had to have pretty much exactly the values they had in order for life to be possible. The physicist Lee Smolin has calculated that the odds of life-compatible numbers coming up by chance is 1 in 10^229.
"Physicists refer to this discovery as the “fine-tuning” of physics for life. What should we make of it? Some take this to be evidence of nothing other than our good fortune. But many prominent scientists—Martin Rees, Alan Guth, Max Tegmark—have taken it to be evidence that we live in a multiverse: that our universe is just one of a huge, perhaps infinite, ensemble of worlds. The hope is that this allows us to give a “monkeys on typewriters” explanation of the fine-tuning. If you have enough monkeys randomly jabbing away on typewriters, it becomes not so improbable that one will happen to write a bit of English. By analogy, if there are enough universes, with enough variation in the numbers in their physics, then it becomes statistically likely that one will happen to have the right numbers for life.
'...experts in the mathematics of probability have identified the inference from the fine-tuning to the multiverse as an instance of fallacious reasoning. Specifically, multiverse theorists commit the inverse gambler’s fallacy, which is a slight twist on the regular gambler’s fallacy. In the regular gambler’s fallacy, the gambler has been at the casino all night and has had a terrible run of bad luck. She thinks to herself, “My next roll of the dice is bound to be a good one, as it’s unlikely I’d roll badly all night!” This is a fallacy, because for any particular roll, the odds of, say, getting a double six are the same: 1/36. How many times the gambler has rolled that night has no bearing on whether the next roll will be a double six.
***
"Philosopher Ian Hacking was the first to connect the inverse gambler’s fallacy to arguments for the multiverse, focusing on physicist John Wheeler’s oscillating universe theory, which held that our universe is the latest of a long temporal sequence of universes. Just as the casino-visitor says “Wow, that person must’ve been playing for a long time, as it’s unlikely they’d have such good luck just from one roll,” so the multiverse theorist says “Wow, there must be many other universes before this one, as it’s unlikely the right numbers would have come up if there’d only been one.”
***
"But isn’t there scientific evidence for a multiverse? Some physicists do indeed think there is a tentative empirical evidence for a kind of multiverse, that described by the hypothesis of eternal inflation. According to eternal inflation, there is a vast, exponentially expanding mega space in which certain regions slow down to form “bubble universes,” our universe being one such bubble universe. However, there is no empirical ground for thinking that the constants of physics—the strength of gravity, the mass of electrons, etc.—are different in these different bubble universes. And without such variation, the fine-tuning problem is even worse: we now have a huge number of monkeys all of whom are typing English.
"?At this point, many bring in string theory. String theory offers a way to make sense of the possibility that the different bubbles might have different constants. On string theory, the supposedly “fixed” numbers of physics are determined by the phase of space, and there are 10500 different possible phases of space in the so-called “string landscape.” It could be that random processes ensure that a wide variety of possibilities from the string landscape are realized in the different bubble universes. Again, however, there is no empirical reason for thinking that this possibility is actual.
"The reason some scientists take seriously the possibility of a multiverse in which the constants vary in different universes is that it seems to explain the fine-tuning. But on closer examination, the inference from fine-tuning to the multiverse proves to be instance of flawed reasoning. So, what should we make of the fine-tuning? Perhaps there is some other way of explaining it. Or perhaps we just got lucky."
Comment: There seems no way out. Shades of John Leslie's discussion in "Universes". Multiverses is simply gambler's fallacy as the author points out. There is no substantive scrap of real evidence, only the attempt at anything but God the designer.
Human evolution: we are entirely improbable
DAVID: A long discussion of the odds:
https://www.scientificamerican.com/article/our-improbable-existence-is-no-evidence-for-...
The heading you have given to this thread is a truly shocking distortion, as part of your attempt to prove that humans were your God’s sole purpose. The article is about the odds against life. It does not specify humans. The brontosaurus, the whale, the crow, the ant, and all the cells of which they are composed are entirely improbable. The heading should read: Evolution: life is entirely improbable.
Quote: "...the universe we live in must be compatible with the existence of life. However, as scientists have studied the fundamental principles that govern our universe, they have discovered that the odds of a universe like ours being compatible with life are astronomically low.”
Tell us something new.
QUOTE: "The reason some scientists take seriously the possibility of a multiverse in which the constants vary in different universes is that it seems to explain the fine-tuning. But on closer examination, the inference from fine-tuning to the multiverse proves to be instance of flawed reasoning. So, what should we make of the fine-tuning? Perhaps there is some other way of explaining it. Or perhaps we just got lucky."
DAVID: There seems no way out. Shades of John Leslie's discussion in "Universes". Multiverses is simply gambler's fallacy as the author points out. There is no substantive scrap of real evidence, only the attempt at anything but God the designer.
Pots and kettles. EVERY explanation is “gambler’s fallacy”! Instead of an infinite, eternal universe or an infinite number of eternal universes producing the right combination, you opt for a mysterious, unknown, eternal, conscious mind without any source creating the only universe we know, containing billions and billions of stars and galaxies coming and going, in order to produce a single dot to contain life. You simply cannot grasp the fact that solving one mystery by substituting another is just as much a “gambler’s fallacy” as the atheist explanation.
RNA can’t work
DAVID: The way life evolved won't ever be found by humans is my point. Hunter and I have made the same comments many times.
And I couldn’t agree more. All explanations are unprovable theories. You have made out an excellent case for agnosticism.
However, I must stress that the purpose of this website is not to proselytize for agnosticism. All of us are looking for clues, and there is an enormous amount to be learned from the search. We should not give up. But after 13 years of discussions, it seems that even you occasionally acknowledge that all paths lead to agnosticism!
Human evolution: we are entirely improbable
by David Turell , Saturday, January 16, 2021, 15:09 (1405 days ago) @ dhw
DAVID: A long discussion of the odds:
https://www.scientificamerican.com/article/our-improbable-existence-is-no-evidence-for-...
dhw: The heading you have given to this thread is a truly shocking distortion, as part of your attempt to prove that humans were your God’s sole purpose. The article is about the odds against life. It does not specify humans. The brontosaurus, the whale, the crow, the ant, and all the cells of which they are composed are entirely improbable. The heading should read: Evolution: life is entirely improbable.
Agreed, but humans are part of all life, and our improbable brain is not explained by anything but a designer.
Quote: "...the universe we live in must be compatible with the existence of life. However, as scientists have studied the fundamental principles that govern our universe, they have discovered that the odds of a universe like ours being compatible with life are astronomically low.”dhw: Tell us something new.
QUOTE: "The reason some scientists take seriously the possibility of a multiverse in which the constants vary in different universes is that it seems to explain the fine-tuning. But on closer examination, the inference from fine-tuning to the multiverse proves to be instance of flawed reasoning. So, what should we make of the fine-tuning? Perhaps there is some other way of explaining it. Or perhaps we just got lucky."
DAVID: There seems no way out. Shades of John Leslie's discussion in "Universes". Multiverses is simply gambler's fallacy as the author points out. There is no substantive scrap of real evidence, only the attempt at anything but God the designer.
Pots and kettles. EVERY explanation is “gambler’s fallacy”! Instead of an infinite, eternal universe or an infinite number of eternal universes producing the right combination, you opt for a mysterious, unknown, eternal, conscious mind without any source creating the only universe we know, containing billions and billions of stars and galaxies coming and going, in order to produce a single dot to contain life. You simply cannot grasp the fact that solving one mystery by substituting another is just as much a “gambler’s fallacy” as the atheist explanation.
The fallacy in your retort is the overwhelming evidence of design, needing a designer.
RNA can’t workDAVID: The way life evolved won't ever be found by humans is my point. Hunter and I have made the same comments many times.
dhw: And I couldn’t agree more. All explanations are unprovable theories. You have made out an excellent case for agnosticism.
However, I must stress that the purpose of this website is not to proselytize for agnosticism. All of us are looking for clues, and there is an enormous amount to be learned from the search. We should not give up. But after 13 years of discussions, it seems that even you occasionally acknowledge that all paths lead to agnosticism!
No, I think the evidence brings belief, and I am an example of an agnostic who was convinced.
Human evolution: we are entirely improbable
dhw: The heading you have given to this thread is a truly shocking distortion, as part of your attempt to prove that humans were your God’s sole purpose. The article is about the odds against life. It does not specify humans. The brontosaurus, the whale, the crow, the ant, and all the cells of which they are composed are entirely improbable. The heading should read: Evolution: life is entirely improbable.
DAVID: Agreed, but humans are part of all life, and our improbable brain is not explained by anything but a designer.
Your heading implies that the article supports your contention that your God’s purpose was to create humans. I’ll stick to our agreement and refrain from relaunching my attack on your general theory of evolution. Thank you for agreeing that your heading is wrong.
DAVID: Multiverses is simply gambler's fallacy as the author points out. There is no substantive scrap of real evidence, only the attempt at anything but God the designer.
dhw: Pots and kettles. EVERY explanation is “gambler’s fallacy”! Instead of an infinite, eternal universe or an infinite number of eternal universes producing the right combination, you opt for a mysterious, unknown, eternal, conscious mind without any source creating the only universe we know, containing billions and billions of stars and galaxies coming and going, in order to produce a single dot to contain life. You simply cannot grasp the fact that solving one mystery by substituting another is just as much a “gambler’s fallacy” as the atheist explanation.
DAVID: The fallacy in your retort is the overwhelming evidence of design, needing a designer.
The fallacy in your retort is that an unknown, eternal, conscious, immaterial mind without any source gives rise to just as many unanswerable questions as the theory that chance assembled the bits and pieces that made up the first living cells. Belief in either demands a huge leap of faith (which you have always acknowledged). You and Dawkins are prepared to leap in your different directions, and of course you have a perfect right to do so. But you should not kid yourselves or us that your respective faiths are supported by science.
RNA can’t work
DAVID: The way life evolved won't ever be found by humans is my point. Hunter and I have made the same comments many times.
dhw: And I couldn’t agree more. All explanations are unprovable theories. You have made out an excellent case for agnosticism.
However, I must stress that the purpose of this website is not to proselytize for agnosticism. All of us are looking for clues, and there is an enormous amount to be learned from the search. We should not give up. But after 13 years of discussions, it seems that even you occasionally acknowledge that all paths lead to agnosticism!
DAVID: No, I think the evidence brings belief, and I am an example of an agnostic who was convinced.
If you believe the way life evolved won’t ever be found by humans, you will never find it, so your belief that you have found it can only mean….but no, I’ve met you. And you are definitely human. 
Human evolution: we are entirely improbable
by David Turell , Sunday, January 17, 2021, 13:45 (1404 days ago) @ dhw
DAVID: Multiverses is simply gambler's fallacy as the author points out. There is no substantive scrap of real evidence, only the attempt at anything but God the designer.
dhw: Pots and kettles. EVERY explanation is “gambler’s fallacy”! Instead of an infinite, eternal universe or an infinite number of eternal universes producing the right combination, you opt for a mysterious, unknown, eternal, conscious mind without any source creating the only universe we know, containing billions and billions of stars and galaxies coming and going, in order to produce a single dot to contain life. You simply cannot grasp the fact that solving one mystery by substituting another is just as much a “gambler’s fallacy” as the atheist explanation.
DAVID: The fallacy in your retort is the overwhelming evidence of design, needing a designer.
dhw: The fallacy in your retort is that an unknown, eternal, conscious, immaterial mind without any source gives rise to just as many unanswerable questions as the theory that chance assembled the bits and pieces that made up the first living cells. Belief in either demands a huge leap of faith (which you have always acknowledged). You and Dawkins are prepared to leap in your different directions, and of course you have a perfect right to do so. But you should not kid yourselves or us that your respective faiths are supported by science.
Dawkins and I see the same scientific facts, but he and I view the design in nature differently. He sees design by magic and I see a designing mind at work and you say on your fence.
RNA can’t workDAVID: The way life evolved won't ever be found by humans is my point. Hunter and I have made the same comments many times.
dhw: And I couldn’t agree more. All explanations are unprovable theories. You have made out an excellent case for agnosticism.
However, I must stress that the purpose of this website is not to proselytize for agnosticism. All of us are looking for clues, and there is an enormous amount to be learned from the search. We should not give up. But after 13 years of discussions, it seems that even you occasionally acknowledge that all paths lead to agnosticism!
DAVID: No, I think the evidence brings belief, and I am an example of an agnostic who was convinced.
dhw: If you believe the way life evolved won’t ever be found by humans, you will never find it, so your belief that you have found it can only mean….but no, I’ve met you. And you are definitely human.
But I can hope
Human evolution: we are entirely improbable
DAVID: The fallacy in your retort is the overwhelming evidence of design, needing a designer.
dhw: The fallacy in your retort is that an unknown, eternal, conscious, immaterial mind without any source gives rise to just as many unanswerable questions as the theory that chance assembled the bits and pieces that made up the first living cells. Belief in either demands a huge leap of faith (which you have always acknowledged). You and Dawkins are prepared to leap in your different directions, and of course you have a perfect right to do so. But you should not kid yourselves or us that your respective faiths are supported by science.
DAVID: Dawkins and I see the same scientific facts, but he and I view the design in nature differently. He sees design by magic and I see a designing mind at work and you say on your fence.
You are simply repeating what I have said. Both of you have blind, unscientific faith in your own interpretation of the facts. Faith is not science. In the next exchange (under “RNA can’t work”) you have actually echoed Dawkins’ vocabulary:
DAVID: The way life evolved won't ever be found by humans is my point. Hunter and I have made the same comments many times.
dhw: […] after 13 years of discussions, it seems that even you occasionally acknowledge that all paths lead to agnosticism!
DAVID: No, I think the evidence brings belief, and I am an example of an agnostic who was convinced.
dhw: If you believe the way life evolved won’t ever be found by humans, you will never find it, so your belief that you have found it can only mean….but no, I’ve met you. And you are definitely human.
DAVID: But I can hope
Yes, you and Dawkins both hope that your diametrically opposite interpretations of the scientific facts will prove to be right, even though you yourself actually acknowledge that we shall never know! My point is that neither of you can claim that your blind faith is based on science.
Human evolution: we are entirely improbable
by David Turell , Monday, January 18, 2021, 15:15 (1403 days ago) @ dhw
DAVID: The fallacy in your retort is the overwhelming evidence of design, needing a designer.
dhw: The fallacy in your retort is that an unknown, eternal, conscious, immaterial mind without any source gives rise to just as many unanswerable questions as the theory that chance assembled the bits and pieces that made up the first living cells. Belief in either demands a huge leap of faith (which you have always acknowledged). You and Dawkins are prepared to leap in your different directions, and of course you have a perfect right to do so. But you should not kid yourselves or us that your respective faiths are supported by science.
DAVID: Dawkins and I see the same scientific facts, but he and I view the design in nature differently. He sees design by magic and I see a designing mind at work and you say on your fence.
dhw: You are simply repeating what I have said. Both of you have blind, unscientific faith in your own interpretation of the facts. Faith is not science. In the next exchange (under “RNA can’t work”) you have actually echoed Dawkins’ vocabulary:
DAVID: The way life evolved won't ever be found by humans is my point. Hunter and I have made the same comments many times.
dhw: […] after 13 years of discussions, it seems that even you occasionally acknowledge that all paths lead to agnosticism!
DAVID: No, I think the evidence brings belief, and I am an example of an agnostic who was convinced.
dhw: If you believe the way life evolved won’t ever be found by humans, you will never find it, so your belief that you have found it can only mean….but no, I’ve met you. And you are definitely human.
DAVID: But I can hope
dhw: Yes, you and Dawkins both hope that your diametrically opposite interpretations of the scientific facts will prove to be right, even though you yourself actually acknowledge that we shall never know! My point is that neither of you can claim that your blind faith is based on science.
I'll stick with my comment above: I think the evidence brings belief, and I am an example of an agnostic who was convinced. And there are tons of evidence.
Human evolution: we are entirely improbable
DAVID: The way life evolved won't ever be found by humans is my point. Hunter and I have made the same comments many times.
dhw: If you believe the way life evolved won’t ever be found by humans, you will never find it, so your belief that you have found it can only mean….but no, I’ve met you. And you are definitely human.
DAVID: But I can hope
dhw: Yes, you and Dawkins both hope that your diametrically opposite interpretations of the scientific facts will prove to be right, even though you yourself actually acknowledge that we shall never know! My point is that neither of you can claim that your blind faith is based on science.
DAVID: I'll stick with my comment above: I think the evidence brings belief, and I am an example of an agnostic who was convinced. And there are tons of evidence.
But you believe humans will never find out how life evolved. The fact that you are now a convinced theist does not mean that your belief is any more scientifically based than that of a convinced atheist. Neither of you can possibly know the truth, and so your respective interpretations of the scientific facts lead you to nothing but hope that you are right. I have absolutely no objections to you and Mr Dawkins having your respective hopes or indeed your respective blind faiths, but I do wish you would both stop kidding yourselves that your hopes and your faiths are somehow supported by science, which is supposed to operate independently of faith, hope and subjectivity!
Human evolution: we are entirely improbable
by David Turell , Tuesday, January 19, 2021, 15:00 (1402 days ago) @ dhw
DAVID: The way life evolved won't ever be found by humans is my point. Hunter and I have made the same comments many times.
dhw: If you believe the way life evolved won’t ever be found by humans, you will never find it, so your belief that you have found it can only mean….but no, I’ve met you. And you are definitely human.
DAVID: But I can hope
dhw: Yes, you and Dawkins both hope that your diametrically opposite interpretations of the scientific facts will prove to be right, even though you yourself actually acknowledge that we shall never know! My point is that neither of you can claim that your blind faith is based on science.
DAVID: I'll stick with my comment above: I think the evidence brings belief, and I am an example of an agnostic who was convinced. And there are tons of evidence.
dhw: But you believe humans will never find out how life evolved. The fact that you are now a convinced theist does not mean that your belief is any more scientifically based than that of a convinced atheist. Neither of you can possibly know the truth, and so your respective interpretations of the scientific facts lead you to nothing but hope that you are right. I have absolutely no objections to you and Mr Dawkins having your respective hopes or indeed your respective blind faiths, but I do wish you would both stop kidding yourselves that your hopes and your faiths are somehow supported by science, which is supposed to operate independently of faith, hope and subjectivity!
I understand that your bottom is completely stuck on the points of your personal picket fence. But I had a reasonable thought conversion from agnosticism discovering factual science about evolution and other considerations. I found evidence beyond a reasonable doubt. I went where the evidence took me. Could your brain be stuck also? 
As for Dawkins, he has a blind eye to the evidence in front of his nose, as presented by ID.
Human evolution: we are entirely improbable
DAVID: The way life evolved won't ever be found by humans is my point. Hunter and I have made the same comments many times.
dhw: If you believe the way life evolved won’t ever be found by humans, you will never find it, so your belief that you have found it can only mean….but no, I’ve met you. And you are definitely human.
DAVID: But I can hope
dhw: Yes, you and Dawkins both hope that your diametrically opposite interpretations of the scientific facts will prove to be right, even though you yourself actually acknowledge that we shall never know! My point is that neither of you can claim that your blind faith is based on science. […]
DAVID: I understand that your bottom is completely stuck on the points of your personal picket fence. But I had a reasonable thought conversion from agnosticism discovering factual science about evolution and other considerations. I found evidence beyond a reasonable doubt. I went where the evidence took me. Could your brain be stuck also? As for Dawkins, he has a blind eye to the evidence in front of his nose, as presented by ID.
According to you, “the way life evolved won’t ever be found by humans”, but you are a human, you have a theory, you think that any doubt is unreasonable, and you hope you are right. Your bottom is stuck on the points of your personal theory. Dawkins is a human, he has a theory, he reckons your theory is a delusion, and he hopes his theory is right. His bottom is stuck on the points of his personal theory. I am a human, I see what I consider to be reasonable doubts about both theories, I acknowledge that the truth “won’t ever be found by humans”, and I keep an open mind. My bottom is stuck on the point that you, Dawkins and I are humans who will never know the truth. Fair summary?
Human evolution: we are entirely improbable
by David Turell , Thursday, January 21, 2021, 01:08 (1400 days ago) @ dhw
DAVID: The way life evolved won't ever be found by humans is my point. Hunter and I have made the same comments many times.
dhw: If you believe the way life evolved won’t ever be found by humans, you will never find it, so your belief that you have found it can only mean….but no, I’ve met you. And you are definitely human.
DAVID: But I can hope
dhw: Yes, you and Dawkins both hope that your diametrically opposite interpretations of the scientific facts will prove to be right, even though you yourself actually acknowledge that we shall never know! My point is that neither of you can claim that your blind faith is based on science. […]
DAVID: I understand that your bottom is completely stuck on the points of your personal picket fence. But I had a reasonable thought conversion from agnosticism discovering factual science about evolution and other considerations. I found evidence beyond a reasonable doubt. I went where the evidence took me. Could your brain be stuck also? As for Dawkins, he has a blind eye to the evidence in front of his nose, as presented by ID.
dhw: According to you, “the way life evolved won’t ever be found by humans”, but you are a human, you have a theory, you think that any doubt is unreasonable, and you hope you are right. Your bottom is stuck on the points of your personal theory. Dawkins is a human, he has a theory, he reckons your theory is a delusion, and he hopes his theory is right. His bottom is stuck on the points of his personal theory. I am a human, I see what I consider to be reasonable doubts about both theories, I acknowledge that the truth “won’t ever be found by humans”, and I keep an open mind. My bottom is stuck on the point that you, Dawkins and I are humans who will never know the truth. Fair summary?
Yes, but we can still keep learning as I put entries here, and add to the evidence beyond a reasonable doubt. Fair summary?
Human evolution: we are entirely improbable
DAVID: I understand that your bottom is completely stuck on the points of your personal picket fence. But I had a reasonable thought conversion from agnosticism discovering factual science about evolution and other considerations. I found evidence beyond a reasonable doubt. I went where the evidence took me. Could your brain be stuck also? As for Dawkins, he has a blind eye to the evidence in front of his nose, as presented by ID.
dhw: According to you, “the way life evolved won’t ever be found by humans”, but you are a human, you have a theory, you think that any doubt is unreasonable, and you hope you are right. Your bottom is stuck on the points of your personal theory. Dawkins is a human, he has a theory, he reckons your theory is a delusion, and he hopes his theory is right. His bottom is stuck on the points of his personal theory. I am a human, I see what I consider to be reasonable doubts about both theories, I acknowledge that the truth “won’t ever be found by humans”, and I keep an open mind. My bottom is stuck on the point that you, Dawkins and I are humans who will never know the truth. Fair summary?
DAVID: Yes, but we can still keep learning as I put entries here, and add to the evidence beyond a reasonable doubt. Fair summary?
Yes to “keep learning” – for which I must reiterate my gratitude – and to the arguments for design (see the theory of cellular intelligence), but emphatically no to “beyond a reasonable doubt” when it comes to the origin of whatever does the designing. i.e. the existence of an unknown, unknowable, eternally conscious, immaterial mind without a source but with infinite powers of psychokinesis.
Human evolution: we are entirely improbable
by David Turell , Thursday, January 21, 2021, 18:44 (1400 days ago) @ dhw
DAVID: Yes, but we can still keep learning as I put entries here, and add to the evidence beyond a reasonable doubt. Fair summary?
dhw: Yes to “keep learning” – for which I must reiterate my gratitude – and to the arguments for design (see the theory of cellular intelligence), but emphatically no to “beyond a reasonable doubt” when it comes to the origin of whatever does the designing. i.e. the existence of an unknown, unknowable, eternally conscious, immaterial mind without a source but with infinite powers of psychokinesis.
"We are discussing the need for a mind that can create by specific designs. Design keeps you agnostic. Why? Design requires a designer.
"Let's look at a philosophic view just published about our improbability:
https://nautil.us/issue/95/escape/is-life-special-just-because-its-rare-rp?mc_cid=d526f...
"Even if all “habitable” planets (as determined by Kepler) do indeed harbor life, the fraction of all material in the universe in living form is fantastically small. Assuming that the fraction of planet Earth in living form, called the biosphere, is typical of other life-sustaining planets, I have estimated that the fraction of all matter in the universe in living form is roughly one-billionth of one-billionth. Here’s a way to visualize such a tiny fraction. If the Gobi Desert represents all of the matter flung across the cosmos, living matter is a single grain of sand on that desert. How should we think about this extreme rarity of life?
***
"Most of us human beings throughout history have considered ourselves and other life forms to contain some special, nonmaterial essence that is absent in nonliving matter and that obeys different principles than does nonliving matter. Such a belief is called “vitalism.” Plato and Aristotle were vitalists. Descartes was a vitalist. Jöns Jakob Berzelius, the 19th-century father of modern chemistry, was a vitalist. The hypothesized nonmaterial vital essence, especially in human beings, has sometimes been called “spirit.” Sometimes “soul.”
***
"there are no hidden and nonmaterial sources of energy that power human beings. In more recent years, the composition of proteins, hormones, brain cells, and genes has been reduced to individual atoms, without the need to invoke nonmaterial substances.
"Yet, I would argue that most of us, either knowingly or unknowingly, remain closet vitalists. Although there are moments when the material nature of our bodies screams out at us, such as when we have muscle injuries or change our mood with psychoactive drugs, our mental life seems to be a unique phenomenon arising from a different kind of substance, a nonmaterial substance. The sensations of consciousness, of thought and self-awareness, are so gripping and immediate and magnificent that we find it preposterous that they could have their origins entirely within the humdrum electrical and chemical tinglings of cells in our brains. However, neuroscientists say that is so.
***
"what is that special arrangement deemed “life?” The ability to form an outer membrane around the organism that separates it from the external world. The ability to organize material and processes within the organism. The ability to extract energy from the external world. The ability to respond to stimuli from the external world. The ability to maintain stability within the organism. The ability to grow. The ability to reproduce. We human beings, of course, have all of these properties and more. For we have billions of neurons connected to each other in an exquisite tapestry of communication and feedback loops. We have consciousness and self-awareness.
***
"there’s another way to think of existence. In our extraordinarily entitled position of being not only living matter but conscious matter, we are the cosmic “observers.” We are uniquely aware of ourselves and the cosmos around us. We can watch and record. We are the only mechanism by which the universe can comment on itself. All the rest, all those other grains of sand on the desert, are dumb, lifeless matter.
***
"Without a mind to observe it, a waterfall is only a waterfall, a mountain is only a mountain. It is we conscious matter, the rarest of all forms of matter, that can take stock and record and announce this cosmic panorama of existence before us.
***
"We cannot imagine a universe without meaning. We are not talking necessarily about some grand cosmic meaning, or a divine meaning bestowed by God, or even a lasting, eternal meaning. But just the simple, particular meaning of everyday events, fleeting events like the momentary play of light on a lake, or the birth of a child. For better or for worse, meaning is part of the way we exist in the world.
"And given our existence, our universe must have meaning, big and small meanings. I have not met any of the life forms living out there in the vast cosmos beyond Earth. But I would be astonished if some of them were not intelligent. And I would be further astonished if those intelligences were not, like us, making science and art and attempting to take stock and record this cosmic panorama of existence. We share with those other beings not the mysterious, transcendent essence of vitalism, but the highly improbable fact of being alive.
Comment: How do you explain our existence? My answer is not by chance!
Human evolution: 350 million year old stone rubbing tool
by David Turell , Thursday, January 21, 2021, 19:36 (1400 days ago) @ David Turell
Probably on soft hides:
https://www.sciencenews.org/article/oldest-known-abrading-tool-archaeology-tabun-cave
"A round stone excavated at Israel’s Tabun Cave in the 1960s represents the oldest known grinding or rubbing tool, say researchers who scrutinized the 350,000-year-old find.
"The specimen marks a technological turn to manipulating objects with wide, flat stone surfaces, say Ron Shimelmitz, an archaeologist at the University of Haifa in Israel, and his colleagues. Up to that time, stone implements had featured thin points or sharp edges. Microscopic wear and polish on a worn section of the Tabun stone resulted from it having been ground or rubbed against relatively soft material, such as animal hides or plants, the scientists conclude
***
"Similar stones bearing signs of abrasion date to no more than around 200,000 years ago. Specific ways in which the Tabun stone was used remain a mystery. By around 50,000 years ago, though, human groups were using grinding stones to prepare plants and other foods, Shimelmitz says.
"The team compared microscopic damage on the Tabun stone to that produced in experiments with nine similar stones collected near the cave site. Archaeology students forcefully ran each of the nine stones back-and-forth for 20 minutes over different surfaces: hard basalt rock, wood of medium hardness or a soft deer hide. Those applied to deer hide displayed much in common with the business end of the ancient stone tool, including a wavy surface and clusters of shallow grooves.
"It’s unclear which evolutionary relatives of Homo sapiens — whose origins go back about 300,000 years—made the Tabun tool, Shimelmitz says. Other innovations around the same time included regular fire use."
Comment: Of course there had to be a progression of learned techniques. The timing is at the earliest possible time for sapiens, as the bolded sentence notes.
Human evolution: we are entirely improbable
DAVID: Yes, but we can still keep learning as I put entries here, and add to the evidence beyond a reasonable doubt. Fair summary?
dhw: Yes to “keep learning” – for which I must reiterate my gratitude – and to the arguments for design (see the theory of cellular intelligence), but emphatically no to “beyond a reasonable doubt” when it comes to the origin of whatever does the designing. i.e. the existence of an unknown, unknowable, eternally conscious, immaterial mind without a source but with infinite powers of psychokinesis.
DAVID: We are discussing the need for a mind that can create by specific designs. Design keeps you agnostic. Why? Design requires a designer.
I shouldn’t need to tell you of all people why I accept the logic of the arguments for design. But I remain agnostic because it is not logical to assume that life and consciousness have to be designed, but the living, conscious designer does not have to be designed.
DAVID: Let's look at a philosophic view just published about our improbability:
https://nautil.us/issue/95/escape/is-life-special-just-because-its-rare-rp?mc_cid=d526f...
There is nothing in this article that we haven’t discussed before, though it’s very nicely written. The conclusion is extraordinarily woolly:
"We cannot imagine a universe without meaning. We are not talking necessarily about some grand cosmic meaning, or a divine meaning bestowed by God, or even a lasting, eternal meaning…."
Good to hear, but here is the grand finale:
“And given our existence, our universe must have meaning, big and small meanings. I have not met any of the life forms living out there in the vast cosmos beyond Earth. But I would be astonished if some of them were not intelligent. And I would be further astonished if those intelligences were not, like us, making science and art and attempting to take stock and record this cosmic panorama of existence. We share with those other beings not the mysterious, transcendent essence of vitalism, but the highly improbable fact of being alive.”
No faith in a God, but pretty solid faith in the existence of ETs who are just like us! I'm a bit surprised by your lack of comment on this.
DAVID: How do you explain our existence? My answer is not by chance!
That is not an explanation. That is the dismissal of an explanation. Just as others would “explain” existence as being “not by an unknown, unknowable, eternally conscious, immaterial mind without a source but with infinite powers of psychokinesis.”
Human evolution: we are entirely improbable
by David Turell , Friday, January 22, 2021, 15:07 (1399 days ago) @ dhw
DAVID: We are discussing the need for a mind that can create by specific designs. Design keeps you agnostic. Why? Design requires a designer.
dhw: I shouldn’t need to tell you of all people why I accept the logic of the arguments for design. But I remain agnostic because it is not logical to assume that life and consciousness have to be designed, but the living, conscious designer does not have to be designed.
We are back to no first cause. I don 't accept nothing became something
DAVID: Let's look at a philosophic view just published about our improbability:
https://nautil.us/issue/95/escape/is-life-special-just-because-its-rare-rp?mc_cid=d526f...dhw: There is nothing in this article that we haven’t discussed before, though it’s very nicely written. The conclusion is extraordinarily woolly:
"We cannot imagine a universe without meaning. We are not talking necessarily about some grand cosmic meaning, or a divine meaning bestowed by God, or even a lasting, eternal meaning…."
Good to hear, but here is the grand finale:
“And given our existence, our universe must have meaning, big and small meanings. I have not met any of the life forms living out there in the vast cosmos beyond Earth. But I would be astonished if some of them were not intelligent. And I would be further astonished if those intelligences were not, like us, making science and art and attempting to take stock and record this cosmic panorama of existence. We share with those other beings not the mysterious, transcendent essence of vitalism, but the highly improbable fact of being alive.”
dhw: No faith in a God, but pretty solid faith in the existence of ETs who are just like us! I'm a bit surprised by your lack of comment on this.
Why? We don't know if any others are there. SETI looks without answers. I assume possible.
DAVID: How do you explain our existence? My answer is not by chance!dhw: That is not an explanation. That is the dismissal of an explanation. Just as others would “explain” existence as being “not by an unknown, unknowable, eternally conscious, immaterial mind without a source but with infinite powers of psychokinesis.”
The evidence of complex designs requires a designing mind. A tornado in a junk yard never makes a 747. For me appealing to chance is totally illogical.
Human evolution: we are entirely improbable
DAVID: We are discussing the need for a mind that can create by specific designs. Design keeps you agnostic. Why? Design requires a designer.
dhw: I shouldn’t need to tell you of all people why I accept the logic of the arguments for design. But I remain agnostic because it is not logical to assume that life and consciousness have to be designed, but the living, conscious designer does not have to be designed.
DAVID: We are back to no first cause. I don't accept nothing became something.
Nor do I. That does not make the above illogical premise logical. And you know that I do not believe in the alternative first causes either (chance, some form of panpsychism).
DAVID: Let's look at a philosophic view just published about our improbability:
https://nautil.us/issue/95/escape/is-life-special-just-because-its-rare-rp?mc_cid=d526f...
dhw: There is nothing in this article that we haven’t discussed before, though it’s very nicely written. The conclusion is extraordinarily woolly:
"We cannot imagine a universe without meaning. We are not talking necessarily about some grand cosmic meaning, or a divine meaning bestowed by God, or even a lasting, eternal meaning…."
Good to hear, but here is the grand finale:
“And given our existence, our universe must have meaning, big and small meanings. I have not met any of the life forms living out there in the vast cosmos beyond Earth. But I would be astonished if some of them were not intelligent. And I would be further astonished if those intelligences were not, like us, making science and art and attempting to take stock and record this cosmic panorama of existence. We share with those other beings not the mysterious, transcendent essence of vitalism, but the highly improbable fact of being alive.”
dhw: No faith in a God, but pretty solid faith in the existence of ETs who are just like us! I'm a bit surprised by your lack of comment on this.
DAVID: Why? We don't know if any others are there. SETI looks without answers. I assume possible.
I thought all our discussions revolved round the existence and purposefulness of your God. Our philosopher deliberately brushes that aside and focuses on ETs in his grand conclusion. I was merely expressing surprise that you accepted this point of focus as the grand climax.
DAVID: How do you explain our existence? My answer is not by chance!
dhw: That is not an explanation. That is the dismissal of an explanation. Just as others would “explain” existence as being “not by an unknown, unknowable, eternally conscious, immaterial mind without a source but with infinite powers of psychokinesis.”
DAVID: The evidence of complex designs requires a designing mind. A tornado in a junk yard never makes a 747. For me appealing to chance is totally illogical.
I am happy to agree with you and Hoyle that chance is illogical. Now look at your explanation: only a living, conscious mind can design life and consciousness, and therefore our life and consciousness were designed by a living, conscious mind which was not designed by anything at all. Logical?
Human evolution: we are entirely improbable
by David Turell , Saturday, January 23, 2021, 19:23 (1398 days ago) @ dhw
DAVID: Let's look at a philosophic view just published about our improbability:
https://nautil.us/issue/95/escape/is-life-special-just-because-its-rare-rp?mc_cid=d526f...dhw: There is nothing in this article that we haven’t discussed before, though it’s very nicely written. The conclusion is extraordinarily woolly:
"We cannot imagine a universe without meaning. We are not talking necessarily about some grand cosmic meaning, or a divine meaning bestowed by God, or even a lasting, eternal meaning…."
Good to hear, but here is the grand finale:
“And given our existence, our universe must have meaning, big and small meanings. I have not met any of the life forms living out there in the vast cosmos beyond Earth. But I would be astonished if some of them were not intelligent. And I would be further astonished if those intelligences were not, like us, making science and art and attempting to take stock and record this cosmic panorama of existence. We share with those other beings not the mysterious, transcendent essence of vitalism, but the highly improbable fact of being alive.”dhw: No faith in a God, but pretty solid faith in the existence of ETs who are just like us! I'm a bit surprised by your lack of comment on this.
DAVID: Why? We don't know if any others are there. SETI looks without answers. I assume possible.
dhw: I thought all our discussions revolved round the existence and purposefulness of your God. Our philosopher deliberately brushes that aside and focuses on ETs in his grand conclusion. I was merely expressing surprise that you accepted this point of focus as the grand climax.
God is purposeful, ant the author didn't completely deny Him.
DAVID: How do you explain our existence? My answer is not by chance!dhw: That is not an explanation. That is the dismissal of an explanation. Just as others would “explain” existence as being “not by an unknown, unknowable, eternally conscious, immaterial mind without a source but with infinite powers of psychokinesis.”
DAVID: The evidence of complex designs requires a designing mind. A tornado in a junk yard never makes a 747. For me appealing to chance is totally illogical.
dhw: I am happy to agree with you and Hoyle that chance is illogical. Now look at your explanation: only a living, conscious mind can design life and consciousness, and therefore our life and consciousness were designed by a living, conscious mind which was not designed by anything at all. Logical?
You deny a first cause, which is not logical.
Human evolution: we are entirely improbable
DAVID: Let's look at a philosophic view just published about our improbability:
https://nautil.us/issue/95/escape/is-life-special-just-because-its-rare-rp?mc_cid=d526f...
dhw: I thought all our discussions revolved round the existence and purposefulness of your God. Our philosopher deliberately brushes that aside and focuses on ETs in his grand conclusion. I was merely expressing surprise that you accepted this point of focus as the grand climax.
DAVID: God is purposeful, and the author didn't completely deny Him.
This is a non-discussion. I was surprised that you had not commented on his woolly conclusion. Now you have commented.
DAVID: How do you explain our existence? My answer is not by chance!
dhw: That is not an explanation. That is the dismissal of an explanation. Just as others would “explain” existence as being “not by an unknown, unknowable, eternally conscious, immaterial mind without a source but with infinite powers of psychokinesis.”
DAVID: The evidence of complex designs requires a designing mind. A tornado in a junk yard never makes a 747. For me appealing to chance is totally illogical.
dhw: I am happy to agree with you and Hoyle that chance is illogical. Now look at your explanation: bbbonly a living, conscious mind can design life and consciousness, and therefore our life and consciousness were designed by a living, conscious mind which was not designed by anything at all. Logical?
DAVID: You deny a first cause, which is not logical.
I have never denied a first cause! I have listed three possible first causes (your God, chance, and some form of panpsychism) but find none of them convincing enough to take a leap of faith. Now please explain the logic of your bolded theory above.
Human evolution: we are entirely improbable
by David Turell , Sunday, January 24, 2021, 16:19 (1397 days ago) @ dhw
DAVID: Let's look at a philosophic view just published about our improbability:
https://nautil.us/issue/95/escape/is-life-special-just-because-its-rare-rp?mc_cid=d526f...DAVID: How do you explain our existence? My answer is not by chance!
dhw: That is not an explanation. That is the dismissal of an explanation. Just as others would “explain” existence as being “not by an unknown, unknowable, eternally conscious, immaterial mind without a source but with infinite powers of psychokinesis.”
DAVID: The evidence of complex designs requires a designing mind. A tornado in a junk yard never makes a 747. For me appealing to chance is totally illogical.
dhw: I am happy to agree with you and Hoyle that chance is illogical. Now look at your explanation: bbbonly a living, conscious mind can design life and consciousness, and therefore our life and consciousness were designed by a living, conscious mind which was not designed by anything at all. Logical?
DAVID: You deny a first cause, which is not logical.
dhw: I have never denied a first cause! I have listed three possible first causes (your God, chance, and some form of panpsychism) but find none of them convincing enough to take a leap of faith. Now please explain the logic of your bolded theory above.
The usual: nothing never produces something. Therefore, as you agree, there must be a first cause. Of your three possibilities, chance is impossible because of the complexities in living biology and panpsychism is a woolly mind-like theory, so why not stick to the obvious: the necessity of an eternal planning mind?
Human evolution: we are entirely improbable
dhw: I am happy to agree with you and Hoyle that chance is illogical. Now look at your explanation: only a living, conscious mind can design life and consciousness, and therefore our life and consciousness were designed by a living, conscious mind which was not designed by anything at all. Logical?
DAVID: You deny a first cause, which is not logical.
dhw: I have never denied a first cause! I have listed three possible first causes (your God, chance, and some form of panpsychism) but find none of them convincing enough to take a leap of faith. Now please explain the logic of your bolded theory above.
DAVID: The usual: nothing never produces something. Therefore, as you agree, there must be a first cause. Of your three possibilities, chance is impossible because of the complexities in living biology and panpsychism is a woolly mind-like theory, so why not stick to the obvious: the necessity of an eternal planning mind?
Why won’t you explain the logic behind the “mind” theory bolded above, which is no less woolly than the woolly “mind-like” theory?
Human evolution: we are entirely improbable
by David Turell , Monday, January 25, 2021, 15:08 (1396 days ago) @ dhw
dhw: I have never denied a first cause! I have listed three possible first causes (your God, chance, and some form of panpsychism) but find none of them convincing enough to take a leap of faith. Now please explain the logic of your bolded theory above.
DAVID: The usual: nothing never produces something. Therefore, as you agree, there must be a first cause. Of your three possibilities, chance is impossible because of the complexities in living biology and panpsychism is a woolly mind-like theory, so why not stick to the obvious: the necessity of an eternal planning mind?
dhw: Why won’t you explain the logic behind the “mind” theory bolded above, which is no less woolly than the woolly “mind-like” theory?
I'm forced to go back to simple principals, evidence beyond a reasonable doubt. The complexity of life requires a designing mind. Our minds are not equal to that mind but our appearance with our minds is not explained by any theory presented by humans. As for panpsychism as an undefined mental force, it is just a variation on the recognition mental activity is required and is a fudge factor in the debate.
Human evolution: we are entirely improbable
dhw: I am happy to agree with you and Hoyle that chance is illogical. Now look at your explanation: only a living, conscious mind can design life and consciousness, and therefore our life and consciousness were designed by a living, conscious mind which was not designed by anything at all. Logical?
DAVID: You deny a first cause, which is not logical.
dhw: I have never denied a first cause! I have listed three possible first causes (your God, chance, and some form of panpsychism) but find none of them convincing enough to take a leap of faith. Now please explain the logic of your bolded theory above.
DAVID: The usual: nothing never produces something. Therefore, as you agree, there must be a first cause. Of your three possibilities, chance is impossible because of the complexities in living biology and panpsychism is a woolly mind-like theory, so why not stick to the obvious: the necessity of an eternal planning mind?
dhw: Why won’t you explain the logic behind the “mind” theory bolded above, which is no less woolly than the woolly “mind-like” theory?
DAVID: I'm forced to go back to simple principals, evidence beyond a reasonable doubt. The complexity of life requires a designing mind. Our minds are not equal to that mind but our appearance with our minds is not explained by any theory presented by humans. As for panpsychism as an undefined mental force, it is just a variation on the recognition mental activity is required and is a fudge factor in the debate.
With the bold, you have at last recognized that NONE of the theories presented by humans can explain our appearance with our minds or the appearance of elephants, whales, brontosauruses, eagles, ants or bacteria with their various minds. Do you not realize that the theory bolded at the beginning of this post – the illogicality of which you continue to ignore – of a universal, eternal, all-powerful, living conscious mind which was not designed by anything at all is a HUMAN theory? Thank you for confirming the logic that underlies agnosticism. But I do not wish to undermine your faith or anybody else’s. I am simply pointing out that neither you nor Dawkins should pretend that your respective faiths in God/mindless nature are based on science. You are of course both welcome to believe whatever you wish to believe!
Human evolution: we are entirely improbable
by David Turell , Wednesday, January 27, 2021, 01:26 (1394 days ago) @ dhw
dhw: I am happy to agree with you and Hoyle that chance is illogical. Now look at your explanation: only a living, conscious mind can design life and consciousness, and therefore our life and consciousness were designed by a living, conscious mind which was not designed by anything at all. Logical?
DAVID: You deny a first cause, which is not logical.
dhw: I have never denied a first cause! I have listed three possible first causes (your God, chance, and some form of panpsychism) but find none of them convincing enough to take a leap of faith. Now please explain the logic of your bolded theory above.
DAVID: The usual: nothing never produces something. Therefore, as you agree, there must be a first cause. Of your three possibilities, chance is impossible because of the complexities in living biology and panpsychism is a woolly mind-like theory, so why not stick to the obvious: the necessity of an eternal planning mind?
dhw: Why won’t you explain the logic behind the “mind” theory bolded above, which is no less woolly than the woolly “mind-like” theory?
DAVID: I'm forced to go back to simple principals, evidence beyond a reasonable doubt. The complexity of life requires a designing mind. Our minds are not equal to that mind but our appearance with our minds is not explained by any theory presented by humans. As for panpsychism as an undefined mental force, it is just a variation on the recognition mental activity is required and is a fudge factor in the debate.
dhw: With the bold, you have at last recognized that NONE of the theories presented by humans can explain our appearance with our minds or the appearance of elephants, whales, brontosauruses, eagles, ants or bacteria with their various minds. Do you not realize that the theory bolded at the beginning of this post – the illogicality of which you continue to ignore – of a universal, eternal, all-powerful, living conscious mind which was not designed by anything at all is a HUMAN theory? Thank you for confirming the logic that underlies agnosticism. But I do not wish to undermine your faith or anybody else’s. I am simply pointing out that neither you nor Dawkins should pretend that your respective faiths in God/mindless nature are based on science. You are of course both welcome to believe whatever you wish to believe!
Neither you nor I have any logical absolute proof. That is why some of us jump Pascal's chasm and some of us don't. To me the evidence is overwhelming, but for you it isn't. As two different humans with two different background we come to different conclusions. That is certainly reasonable and logical. Ultimately despite years of debate we can not change each other. But I'll continue looking in the internet for new news to present as I have overwhelmed you with unexplained design in biological beings. I have an explanation that satisfies me. I'm sorry you are not satisfied.
Human evolution: we are entirely improbable
dhw: I am happy to agree with you and Hoyle that chance is illogical. Now look at your explanation: only a living, conscious mind can design life and consciousness, and therefore our life and consciousness were designed by a living, conscious mind which was not designed by anything at all. Logical? […]
DAVID: I'm forced to go back to simple principals, evidence beyond a reasonable doubt. The complexity of life requires a designing mind. Our minds are not equal to that mind but our appearance with our minds is not explained by any theory presented by humans. As for panpsychism as an undefined mental force, it is just a variation on the recognition mental activity is required and is a fudge factor in the debate.
dhw: With the bold, you have at last recognized that NONE of the theories presented by humans can explain our appearance with our minds or the appearance of elephants, whales, brontosauruses, eagles, ants or bacteria with their various minds. Do you not realize that the theory bolded at the beginning of this post – the illogicality of which you continue to ignore – of a universal, eternal, all-powerful, living conscious mind which was not designed by anything at all is a HUMAN theory? Thank you for confirming the logic that underlies agnosticism. But I do not wish to undermine your faith or anybody else’s. I am simply pointing out that neither you nor Dawkins should pretend that your respective faiths in God/mindless nature are based on science. You are of course both welcome to believe whatever you wish to believe!
DAVID: Neither you nor I have any logical absolute proof. That is why some of us jump Pascal's chasm and some of us don't. To me the evidence is overwhelming, but for you it isn't. As two different humans with two different background we come to different conclusions. That is certainly reasonable and logical.
Not quite. I do not come to one definite conclusion, whereas you do. This applies both to first cause and to theories of evolution. You claim that you have evidence “beyond a reasonable doubt” for your theories and dismiss any alternatives, but you do not or cannot provide any logical answers to my questions. That is why you have now dodged the bolded objection to your God theory at the start of this post!
DAVID: Ultimately despite years of debate we can not change each other. But I'll continue looking in the internet for new news to present as I have overwhelmed you with unexplained design in biological beings. I have an explanation that satisfies me. I'm sorry you are not satisfied.
I am as always hugely grateful for the news you offer us, without which this website would certainly have to close down. And I have no problem with the fact that your faith satisfies you. But I shall continue to probe your arguments if I find them illogical, and I shall continue to offer alternatives if I think they are logical. Such discussions are the purpose of any forum, as I’m sure you’ll agree.
Human evolution: we are entirely improbable
by David Turell , Wednesday, January 27, 2021, 15:33 (1394 days ago) @ dhw
dhw: I am happy to agree with you and Hoyle that chance is illogical. Now look at your explanation: only a living, conscious mind can design life and consciousness, and therefore our life and consciousness were designed by a living, conscious mind which was not designed by anything at all. Logical? […]
DAVID: Neither you nor I have any logical absolute proof. That is why some of us jump Pascal's chasm and some of us don't. To me the evidence is overwhelming, but for you it isn't. As two different humans with two different background we come to different conclusions. That is certainly reasonable and logical.
Not quite. I do not come to one definite conclusion, whereas you do. This applies both to first cause and to theories of evolution. You claim that you have evidence “beyond a reasonable doubt” for your theories and dismiss any alternatives, but you do not or cannot provide any logical answers to my questions. That is why you have now dodged the bolded objection to your God theory at the start of this post!
Reproduced here: "only a living, conscious mind can design life and consciousness, and therefore our life and consciousness were designed by a living, conscious mind which was not designed by anything at all. Logical?" Of course logical. Design requires a designer and without a first cause there is nothing. Logical?
DAVID: Ultimately despite years of debate we can not change each other. But I'll continue looking in the internet for new news to present as I have overwhelmed you with unexplained design in biological beings. I have an explanation that satisfies me. I'm sorry you are not satisfied.dhw: I am as always hugely grateful for the news you offer us, without which this website would certainly have to close down. And I have no problem with the fact that your faith satisfies you. But I shall continue to probe your arguments if I find them illogical, and I shall continue to offer alternatives if I think they are logical. Such discussions are the purpose of any forum, as I’m sure you’ll agree.
Yes, new news of science discoveries will continue as long I can and fuel our discussions
Human evolution: early thumb tool grip advance
by David Turell , Thursday, January 28, 2021, 18:58 (1393 days ago) @ David Turell
Our current thumb grip is well beyond our ancestors:
https://www.sciencenews.org/article/humanlike-thumb-dexterity-hominid-evolution
"Thumb dexterity similar to that of people today already existed around 2 million years ago, possibly in some of the earliest members of our own genus Homo, a new study indicates. The finding is the oldest evidence to date of an evolutionary transition to hands with powerful grips comparable to those of human toolmakers, who didn’t appear for roughly another 1.7 million years.
"Thumbs that enabled a forceful grip and improved the ability to manipulate objects gave ancient Homo or a closely related hominid line an evolutionary advantage over hominid contemporaries, says a team led by Fotios Alexandros Karakostis and Katerina Harvati. Now-extinct Australopithecus made and used stone tools but lacked humanlike thumb dexterity, thus limiting its toolmaking capacity, the paleoanthropologists, from Eberhard Karls University of Tübingen in Germany, found.
"The researchers digitally simulated how a key muscle influenced thumb movement in 12 previously found fossil hominids, five 19th century humans and five chimpanzees. Surprisingly, Harvati says, a pair of roughly 2-million-year-old thumb fossils from South Africa display agility and power on a par with modern human thumbs.
"Scientists disagree about whether the South African finds come from early Homo or Paranthropus robustus, a species on a dead-end branch of hominid evolution. But the thumb dexterity in those ancient fossils is comparable to that found in members of Homo species that appeared after around 335,000 years ago, the researchers report January 28 in Current Biology. That includes Neandertals from Europe and the Middle East, and a South African hominid dubbed Homo naledi, which possessed an unusual mix of skeletal traits.
***
"Harvati’s team went beyond past efforts that focused only on the size and shape of ancient hominids’ hand bones. Using data from humans and chimpanzees on how hand muscles and bones interact while moving, the researchers constructed a digital, 3-D model to re-create how a key thumb muscle — musculus opponens pollicis — attached to a bone at the base of the thumb and operated to bend the digit’s joint toward the palm and fingers.
"These new models of how ancient thumbs worked underscore the slowness of hominid hand evolution, says paleoanthropologist Matthew Tocheri of Lakehead University in Thunder Bay, Canada. Australopithecus made and used stone tools as early as around 3.3 million years ago (SN: 5/20/15). “But we don’t see major changes to the thumb until around 2 million years ago, soon after which stone artifacts become far more common across the African landscape,” he says."
Comment: The dexterity of our hands and the opposable force of our thumbs make our hands vastly more useable than apes or early forms like Lucy. I can't imagine an ancient hominin playing the piano or violin.
Human evolution: early thumb tool grip advance
by David Turell , Friday, January 29, 2021, 00:45 (1392 days ago) @ David Turell
More interesting thoughts and anew approach to brain and hand development relationships:
https://cosmosmagazine.com/the-body/thumbs-up-and-over/?utm_source=Cosmos+-+Master+Mail...
"Dexterous thumbs – considered a hallmark of being human – were present two million years ago, according to a study published in the journal Current Biology.
"This was around the time that more systematic tool production and complex cultural developments emerged and our large-brained Homo erectus ancestors appeared on the scene, highlighting the pivotal importance of thumb evolution.
“'Increased thumb dexterity [offered] a crucial evolutionary advantage for the gradual development of sophisticated behaviour and culture,” says senior author Katerina Harvati, from Eberhard Karls University of Tübingen, Germany.
“'Importantly, the fact that all later species of Homo maintained, or independently developed, increased levels of dexterity underlines the vital adaptive value of thumb opposition efficiency in human evolution.”
***
"more recent hominins showed greater levels of thumb dexterity similar to those of modern humans, including Neanderthals and Homo sapiens, as well as Homo naledi.
“'It is worth noting that the enigmatic and small-brained species Homo naledi also showed similarly high levels of dexterity,” says Harvati, “despite the fact that its cultural remains are still to be discovered.”
"But “such enhanced manual abilities in this small-brained species suggest a decoupling of the traditionally assumed correlation between brain size and tool-using skills in the fossil record”, the authors write." (my bold)
Comment: The bold is a very interesting take on how advances in human development are related if at all. My view, with God as the designer, decoupling makes sense, as it is up to Him to decide wherever when to create advances in hominin and homo forms.
Human evolution: early thumb tool grip advance
DAVID: The dexterity of our hands and the opposable force of our thumbs make our hands vastly more useable than apes or early forms like Lucy. I can't imagine an ancient hominin playing the piano or violin.
So what are you proposing here? That 2 million years ago, your God stepped in to design opposable thumbs, anticipating H. sapiens’ invention of the piano and violin? Or is it possible that these homos had conceived of artefacts that required additional dexterity, and the process of making and improving on these artefacts RESULTED in more efficient thumbs?
QUOTE: “such enhanced manual abilities in this small-brained species suggest a decoupling of the traditionally assumed correlation between brain size and tool-using skills in the fossil record”, the authors write." (David’s bold)
DAVID: The bold is a very interesting take on how advances in human development are related if at all. My view, with God as the designer, decoupling makes sense, as it is up to Him to decide wherever when to create advances in hominin and homo forms.
It also makes sense that the smaller brain can come up with new ideas, and the implementation of those new ideas may result in anatomical changes – not necessarily in the brain. It ties in with the whole principle of the cell communities responding to new requirements (in this case implementing the idea for a new artefact). I really don’t know why you think your God had to preprogramme all this 3.8 billion years ago, or to keep stepping in and operating on countless thumbs and pre-whale legs and human brains and pelvises when all he had to do was give cells the intelligence to restructure themselves, as we know they do during processes of adaptation.
Human evolution: early thumb tool grip advance
by David Turell , Saturday, January 30, 2021, 00:17 (1391 days ago) @ dhw
DAVID: The dexterity of our hands and the opposable force of our thumbs make our hands vastly more useable than apes or early forms like Lucy. I can't imagine an ancient hominin playing the piano or violin.
dhw: So what are you proposing here? That 2 million years ago, your God stepped in to design opposable thumbs, anticipating H. sapiens’ invention of the piano and violin? Or is it possible that these homos had conceived of artefacts that required additional dexterity, and the process of making and improving on these artefacts RESULTED in more efficient thumbs?
Think it through! Two million years ago who walked the earth? Early erectus and some older forms dying out:
https://www.sciencenews.org/article/hominid-transition-occurred-southern-africa-2-milli...
Early small-brained erectus made stone tools so the new form of thumb from God was more useful, and anticipated the bigger brain hand uses later.
QUOTE: “such enhanced manual abilities in this small-brained species suggest a decoupling of the traditionally assumed correlation between brain size and tool-using skills in the fossil record”, the authors write." (David’s bold)DAVID: The bold is a very interesting take on how advances in human development are related if at all. My view, with God as the designer, decoupling makes sense, as it is up to Him to decide wherever when to create advances in hominin and homo forms.
dhw: It also makes sense that the smaller brain can come up with new ideas, and the implementation of those new ideas may result in anatomical changes – not necessarily in the brain. It ties in with the whole principle of the cell communities responding to new requirements (in this case implementing the idea for a new artefact). I really don’t know why you think your God had to preprogramme all this 3.8 billion years ago, or to keep stepping in and operating on countless thumbs and pre-whale legs and human brains and pelvises when all he had to do was give cells the intelligence to restructure themselves, as we know they do during processes of adaptation.
You know exactly why I think as I do. God designs advances. God could not pack into cells His knowledge of design. It is always easier to just design it yourself as I have done in architectural designs in the past. You seem to love your second-hand God character, a weak confused fellow.
Human evolution: early thumb tool grip advance
DAVID: The dexterity of our hands and the opposable force of our thumbs make our hands vastly more useable than apes or early forms like Lucy. I can't imagine an ancient hominin playing the piano or violin.
dhw: So what are you proposing here? That 2 million years ago, your God stepped in to design opposable thumbs, anticipating H. sapiens’ invention of the piano and violin? Or is it possible that these homos had conceived of artefacts that required additional dexterity, and the process of making and improving on these artefacts RESULTED in more efficient thumbs?
DAVID: Think it through! Two million years ago who walked the earth? Early erectus and some older forms dying out:
Am I saying they didn’t? I am simply asking you if you think your God stepped in to design opposable thumbs in anticipation of pianos and violins two million years later, or did early erectus have new ideas which required greater dexterity for their implementation, resulting in changes to the thumb? Your next comment doesn’t help:
DAVID: Early small-brained erectus made stone tools so the new form of thumb from God was more useful, and anticipated the bigger brain hand uses later.
What do you mean here by “anticipated”? You keep telling us that he popped in to perform his operations. So he popped in to give erectus a waggly thumb because he knew that a million years later he was going to give someone else a wagglier hand and a bigger brain?
dhw: I really don’t know why you think your God had to preprogramme all this 3.8 billion years ago, or to keep stepping in and operating on countless thumbs and pre-whale legs and human brains and pelvises when all he had to do was give cells the intelligence to restructure themselves, as we know they do during processes of adaptation.
DAVID: You know exactly why I think as I do. God designs advances. God could not pack into cells His knowledge of design. It is always easier to just design it yourself as I have done in architectural designs in the past. You seem to love your second-hand God character, a weak confused fellow.
I know you think he designs every single evolutionary change, but I have no idea why “you think as you do”. I’m not going to denigrate your skills in architectural design, but you obviously believe you did it yourself. Do you think your God would have found it easier for himself to pop in and do it for you? You have him either devising a 3.8-billion-year-old programme for every life form, econiche, strategy, lifestyle and natural wonder, or popping in over and over again to give special courses to weaverbirds and cuttlefish, or to perform operations on legs and fins, thumbs, hands, pelvises, brains etc. But he does it because this is “easier” for him than giving them the ability to do it all themselves!
And finally, there is nothing second-hand, weak or confused about a God who knows what he wants, designs it, and gets it.
Human evolution: early thumb tool grip advance
by David Turell , Saturday, January 30, 2021, 14:19 (1391 days ago) @ dhw
DAVID: Think it through! Two million years ago who walked the earth? Early erectus and some older forms dying out:
dhw: Am I saying they didn’t? I am simply asking you if you think your God stepped in to design opposable thumbs in anticipation of pianos and violins two million years later, or did early erectus have new ideas which required greater dexterity for their implementation, resulting in changes to the thumb? Your next comment doesn’t help:
DAVID: Early small-brained erectus made stone tools so the new form of thumb from God was more useful, and anticipated the bigger brain hand uses later.
dhw: What do you mean here by “anticipated”? You keep telling us that he popped in to perform his operations. So he popped in to give erectus a waggly thumb because he knew that a million years later he was going to give someone else a wagglier hand and a bigger brain?
My God designs advances as He speciates.
dhw: I really don’t know why you think your God had to preprogramme all this 3.8 billion years ago, or to keep stepping in and operating on countless thumbs and pre-whale legs and human brains and pelvises when all he had to do was give cells the intelligence to restructure themselves, as we know they do during processes of adaptation.DAVID: You know exactly why I think as I do. God designs advances. God could not pack into cells His knowledge of design. It is always easier to just design it yourself as I have done in architectural designs in the past. You seem to love your second-hand God character, a weak confused fellow.
dhw: I know you think he designs every single evolutionary change, but I have no idea why “you think as you do”. I’m not going to denigrate your skills in architectural design, but you obviously believe you did it yourself. Do you think your God would have found it easier for himself to pop in and do it for you? You have him either devising a 3.8-billion-year-old programme for every life form, econiche, strategy, lifestyle and natural wonder, or popping in over and over again to give special courses to weaverbirds and cuttlefish, or to perform operations on legs and fins, thumbs, hands, pelvises, brains etc. But he does it because this is “easier” for him than giving them the ability to do it all themselves!dhw: And finally, there is nothing second-hand, weak or confused about a God who knows what he wants, designs it, and gets it.
Finally we agree on something, although I'm sure our interpretations of that statement really differ.
Human evolution: early thumb tool grip advance
DAVID: Early small-brained erectus made stone tools so the new form of thumb from God was more useful, and anticipated the bigger brain hand uses later.
dhw: What do you mean here by “anticipated”? You keep telling us that he popped in to perform his operations. So he popped in to give erectus a waggly thumb because he knew that a million years later he was going to give someone else a wagglier hand and a bigger brain?
DAVID: My God designs advances as He speciates.
I know your interpretation of evolution is that 3.8 billion years ago your God devised programmes for every single life form, econiche, lifestyle and natural wonder except for those he created by direct intervention, e.g. by performing operations on a group of homos to give each of them two flexible thumbs so that two million years later, after a few more operations, their descendants could invent and play the piano. And I am amazed by your next claim:
DAVID: God designs advances. God could not pack into cells His knowledge of design. It is always easier to just design it yourself as I have done in architectural designs in the past. You seem to love your second-hand God character, a weak confused fellow.
I really don’t know how it can be “easier” to perform millions of operations on millions of organisms, and to offer millions of courses in subjects like camouflage and nest-building, than to provide organisms with the means of doing their own designing.
dhw: And finally, there is nothing second-hand, weak or confused about a God who knows what he wants, designs it, and gets it.
DAVID: Finally we agree on something, although I'm sure our interpretations of that statement really differ.
They certainly do. According to you, your God designed all sorts of nasty things, but he didn’t want to, and you just hope there’s going to be a nice explanation, though you can’t find one. And you think that makes him strong and clear-minded. Whereas apparently (see “Theodicy”) a God who wants to create something interesting for himself and does so is weak and confused.
Human evolution: early thumb tool grip advance
by David Turell , Sunday, January 31, 2021, 18:43 (1390 days ago) @ dhw
DAVID: Early small-brained erectus made stone tools so the new form of thumb from God was more useful, and anticipated the bigger brain hand uses later.
dhw: What do you mean here by “anticipated”? You keep telling us that he popped in to perform his operations. So he popped in to give erectus a waggly thumb because he knew that a million years later he was going to give someone else a wagglier hand and a bigger brain?
DAVID: My God designs advances as He speciates.
dhw: I know your interpretation of evolution is that 3.8 billion years ago your God devised programmes for every single life form, econiche, lifestyle and natural wonder except for those he created by direct intervention, e.g. by performing operations on a group of homos to give each of them two flexible thumbs so that two million years later, after a few more operations, their descendants could invent and play the piano. And I am amazed by your next claim:
DAVID: God designs advances. God could not pack into cells His knowledge of design. It is always easier to just design it yourself as I have done in architectural designs in the past. You seem to love your second-hand God character, a weak confused fellow.
dhw: I really don’t know how it can be “easier” to perform millions of operations on millions of organisms, and to offer millions of courses in subjects like camouflage and nest-building, than to provide organisms with the means of doing their own designing.
You again diminish God's purpose and powers. He created a universe that permitted our appearance based on quantum mechanics we still don't understand. Note that point. His creativeness remains beyond our understanding, no matter how hard we try. He must have very complex mental ability well beyond what He granted us. But I still wish to try and understand as I think you do.
dhw: And finally, there is nothing second-hand, weak or confused about a God who knows what he wants, designs it, and gets it.
DAVID: Finally we agree on something, although I'm sure our interpretations of that statement really differ.
dhw: They certainly do. According to you, your God designed all sorts of nasty things, but he didn’t want to,
Don't misinterpret me. Everything here is part of his desired creations.
dhw: and you just hope there’s going to be a nice explanation, though you can’t find one. And you think that makes him strong and clear-minded. Whereas apparently (see “Theodicy”) a God who wants to create something interesting for himself and does so is weak and confused.
Just your very humanized version of a God, to which you remain blinded by your inadequate concepts of God.
Human evolution: Neanderthals absorbed
by David Turell , Thursday, February 04, 2021, 15:08 (1386 days ago) @ David Turell
We didn't wipe them out, we simply interbred, a new approach:
https://gizmodo.com/more-evidence-that-neanderthals-were-absorbed-by-huma-1846173050
:Prehistoric teeth found over 100 years ago are some of the best evidence yet for hybridized communities of Neanderthals and modern humans.
"We know that Neanderthals and early modern humans interbred—our DNA tells us so—but fossil evidence in this regard is surprisingly lacking. Hence the importance of the new research paper, published today in the Journal of Human Evolution.
"The evidence consists of prehistoric teeth recovered from the La Cotte de St. Brelade cave site in Jersey, an island located in the English Channel, in 1910 and 1911. The teeth, belonging to two individuals, exhibit characteristics consistent with interbreeding, pointing to the presence of hybridized populations.
"There is now “considerable DNA evidence that interbreeding happened, both from fossils and modern genomes,” Chris Stringer, a co-author of the new study and an archaeologist at the Natural History Museum in London, explained in an email. Indeed, most people with recent ancestry from outside of Africa have around 2% Neanderthal DNA in their genomes. That said, archaeologists “still don’t know the exact circumstances, nor how much this was a blending absorption of the Neanderthals into expanding modern human populations,” added Stringer.
"That communities of mixed ancestry existed during the Middle Paleolithic, some 48,000 years ago, is potential evidence that “extinction” is probably not the best word to describe the fate of Neanderthals. Instead, these hominins, and their DNA, were absorbed by the increasingly dominant newcomers to Europe: modern humans (Homo sapiens).
***
"The remaining 11 teeth, it was determined, belonged not to one but two individuals. Importantly, the teeth exhibited signs of hybridization.
“We find the same unusual combinations of Neanderthal and modern human traits in the teeth of both identified Neanderthal individuals,” said Stringer. “We consider this the strongest direct evidence yet found in fossils, although we don’t yet have DNA evidence to back this up. In summary, the tooth roots look very Neanderthal, whereas the neck and crowns of the teeth look much more like those of modern humans.”
***
"Recent dating of sediments at the site suggests the teeth are approximately 48,000 years old, which places them roughly 8,000 years prior to the extinction of the Neanderthals. These archaic humans emerged some 400,000 years ago, and their remains have been found all across Eurasia. The finds at La Cotte de St. Brelade, therefore, are from a late stage of the species. Indeed, this was a critical time in human history, as early modern humans were spreading across Europe and breeding with Neanderthals.
"The reasons for Neanderthal extinction remain unclear, but going theories include violent conflict with modern humans, disease, climate change (and an inability to adapt), and, as mentioned, interbreeding. That Neanderthals were absorbed into our species seems an increasingly plausible explanation."
Comment: makes lots of sense.
Human evolution: viral DNA in us
by David Turell , Sunday, February 14, 2021, 15:39 (1376 days ago) @ David Turell
With the arrival of DNA analysis we find viral DN A plays an important role:
http://cshl.nautil.us/article/498/the-non-human-living-inside-of-you?mc_cid=f562e49356&...
"The human genome contains billions of pieces of information and around 22,000 genes, but not all of it is, strictly speaking, human. Eight percent of our DNA consists of remnants of ancient viruses, and another 40 percent is made up of repetitive strings of genetic letters that is also thought to have a viral origin. Those extensive viral regions are much more than evolutionary relics: They may be deeply involved with a wide range of diseases including multiple sclerosis, hemophilia, and amyotrophic lateral sclerosis (ALS), along with certain types of dementia and cancer.
***
An early clue came from the pioneering geneticist Barbara McClintock, who spent much of her career at CSHL. In the 1940s, long before the decoding of the human genome, she realized that some stretches of our DNA behave like infectious invaders. These DNA chunks can move around through the genome, copying and pasting themselves wherever they see fit, which inspired McClintock to call them “jumping genes.” Her once-controversial idea earned her a Nobel Prize in 1983.
***
"Much of the research on the connection between jumping genes and disease has focused on natural molecules in the body that immobilize the genes by blocking their sequences from being read or copied. In recent years, Hammell and a number of scientists have focused specifically on a once-obscure protein known as TDP-43, which is highly adept at latching onto and hiding stretches of DNA.
"Avi Nath, the clinical director of the National Institute for Neurological Disease and Stroke, helped draw attention to the importance of TDP-43 starting a decade ago. While studying a group of HIV-positive patients with ALS-like symptoms, Nath found that the anti-HIV drugs they were taking were also improving their ALS symptoms. He suspected that the drugs designed to fight the HIV virus were also suppressing the virus-like activity from jumping genes.
"Subsequent work by Nath and others bolstered that idea, identifying a specific group of viral relics that seemed to be associated with dead neurons in the brains of ALS patients. A study led by biochemist Wenxue Li, now at Yale University, further showed that the ancient viruses in question interacts strongly with TDP-43.
"At this point, the puzzle pieces began to fall into place. Medical researchers already knew that nearly all ALS patients experience a severe TDP-43 malfunction that causes large amounts of that protein to build up in their neurons, where it forms toxic clumps. Now it appears that TDP-43 could contribute to ALS in another way: The faulty form of the protein might no longer be able to hold back critical nerve-killing jumping genes.
"Over the past two years, Hammell has confirmed that the normal form of TDP-43 suppresses harmful activity from jumping genes in mice and humans. Other researchers have found that TDP-43 malfunction is also associated with certain types of Alzheimer’s and dementia.
"The case is still not completely solved. Hammell and Nath cannot yet say for certain whether jumping genes cause ALS in some patients, or whether their activity is a byproduct of the way that ALS progresses. But either way, researchers have an important new goal in treating neurodegenerative disease: taming the non-human portion of our genome."
Comment: I assume God designed viruses like all of life (recognizing viruses are half-alive). Viruses play a role in evolution which makes that design reasonable. TDP-43 offers good control of events, until it is damaged or changed. This is a mistake by a molecule. I don't think we should blame God. Normal TDP-43 is God's designed protection, but molecules can make their own mistakes outside of His controls.
Human evolution: Neanderthal research about speech
by David Turell , Monday, March 01, 2021, 19:47 (1361 days ago) @ David Turell
They had the ability:
https://phys.org/news/2021-03-neandertals-capacity-human-speech.html
"'This is one of the most important studies I have been involved in during my career", says Quam. "The results are solid and clearly show the Neandertals had the capacity to perceive and produce human speech. This is one of the very few current, ongoing research lines relying on fossil evidence to study the evolution of language, a notoriously tricky subject in anthropology."
"The evolution of language, and the linguistic capacities in Neandertals in particular, is a long-standing question in human evolution.
***
"The study relied on high resolution CT scans to create virtual 3-D models of the ear structures in Homo sapiens and Neandertals as well as earlier fossils from the site of Atapuerca that represent ancestors of the Neandertals. Data collected on the 3-D models were entered into a software-based model, developed in the field of auditory bioengineering, to estimate the hearing abilities up to 5 kHz, which encompasses most of the frequency range of modern human speech sounds. Compared with the Atapuerca fossils, the Neandertals showed slightly better hearing between 4-5 kHz, resembling modern humans more closely.
"In addition, the researchers were able to calculate the frequency range of maximum sensitivity, technically known as the occupied bandwidth, in each species. The occupied bandwidth is related to the communication system, such that a wider bandwidth allows for a larger number of easily distinguishable acoustic signals to be used in the oral communication of a species. This, in turn, improves the efficiency of communication, the ability to deliver a clear message in the shortest amount of time. The Neandertals show a wider bandwidth compared with their ancestors from Atapuerca, more closely resembling modern humans in this feature.
***
"Thus, Neandertals had a similar capacity to us to produce the sounds of human speech, and their ear was "tuned" to perceive these frequencies. This change in the auditory capacities in Neandertals, compared with their ancestors from Atapuerca, parallels archaeological evidence for increasingly complex behavioral patterns, including changes in stone tool technology, domestication of fire and possible symbolic practices. Thus, the study provides strong evidence in favor of the coevolution of increasingly complex behaviors and increasing efficiency in vocal communication throughout the course of human evolution."
Comment: This study is based on preserved ear bones. Its weakness is the assumption that the auditory area of the brain was structurally advanced enough to handle the sounds of speech and make speech. My guess is, yes it was.
Human evolution: your gut has a big brain
by David Turell , Wednesday, March 03, 2021, 20:50 (1359 days ago) @ David Turell
A network of 100 million neurons:
https://www.realclearscience.com/blog/2021/03/02/why_is_the_gut_so_emotional_661147.html
"...the gut is home to at least 100 million neurons, and perhaps as many as 500 million, by far the most outside of the brain. Concentrated in the lining of the gastrointestinal system, embedded in the esophagus and even the anus, these neurons constitute what scientists have dubbed the "enteric nervous system." Through the vagus nerve, this 'second brain' has a direct line to the primary one in your skull, and as you've undoubtedly noticed, it likes to talk.
"Sorting out all of these communications and their possible effects is now the focus of a burgeoning field: neurogastroenterology. It's increasingly apparent that what goes on in the gut affects the brain and vice versa. Nowhere is this more obvious than with mood. More than 95% of the body's serotonin, a hormone that stabilizes mood, feelings of well-being, and happiness, is found in the enteric nervous system. Is it any wonder then, that an empty stomach can make you irritable and impatient, clear signs of 'hanger'? About half of the body's dopamine is found in the gut, too. As the primary 'pleasure hormone,' it's responsible for the bliss you feel while imbibing a milkshake or devouring a fried chicken sandwich.
"The gut-brain relationship can go in the opposite direction as well – what's going on in the brain can rouse the stomach. This explains 'excited butterflies' before a first date or 'anxious aches' as an important deadline approaches.
"Sometimes the relationship can go awry. Habitually poor diet can result in depression. Chronic stress can contribute to irritable bowel syndrome. The gut-brain connection explains how mental health issues can trigger very real and debilitating physical symptoms.
***
"Research (mostly in the laboratory, but some in humans) suggests that emotions can affect the gut microbiota, and that, conversely, certain gut microbes can be mind-altering," Dan Gordon wrote in U Magazine.
"'We have been cohabiting with these bacteria for hundreds of thousands of years, and we have developed a relationship we haven’t even started to understand," Dr. Claudia Sanmiguel, program director of the Ingestive Behavior and Obesity Program in the UCLA Vatche and Tamar Manoukian Division of Digestive Diseases, told Gordon.
"A study published in 2018 found that individuals with higher levels of a chemical metabolite called indole in their microbiome were more likely to eat for pleasure rather than hunger.
"'Research (mostly in the laboratory, but some in humans) suggests that emotions can affect the gut microbiota, and that, conversely, certain gut microbes can be mind-altering," Dan Gordon wrote in U Magazine.
"'We have been cohabiting with these bacteria for hundreds of thousands of years, and we have developed a relationship we haven’t even started to understand," Dr. Claudia Sanmiguel, program director of the Ingestive Behavior and Obesity Program in the UCLA Vatche and Tamar Manoukian Division of Digestive Diseases, told Gordon.
"A study published in 2018 found that individuals with higher levels of a chemical metabolite called indole in their microbiome were more likely to eat for pleasure rather than hunger."
Comment: I assume lesser animals have these effects but their lesser brains may not react as ours do. Obviously we have know hunger and no hunger. But the full connection involves the gut biome which again notes the significance of bacteria being around since the start of life.
Human evolution: your gut has a big brain
by David Turell , Tuesday, September 21, 2021, 18:45 (1157 days ago) @ David Turell
How glia exercise control:
https://medicalxpress.com/news/2021-09-gut-remarkable-role-intestinal-cells.html
"The Gulbransen lab studies enteric glial cells and how they regulate processes in the gut. "Lately researchers have noticed glia have active signaling roles—they talk to other glia, to neurons and to immune cells to regulate homeostasis, like a rheostat that turns neuron activity up or down," he explained.
"Hundreds of millions of neurons line the digestive tract to make the enteric nervous system. It has more neurons than the spinal cord, and the enteric glial cells surround each one. But for a long time, scientists were not excited about glia because they were not excitable cells—electrically speaking.
"'Once scientists could image other types of activity, they discovered the glia do exhibit forms of fast activity, just in different ways, through a type of firing mediated by calcium that allows them to signal to the neurons," said Gulbransen, who was just finishing a Ph.D. in neuroscience at the University Of Colorado Hospital in 2007 when new research suggested that glia not only communicated with other cells, but also expressed an antigen known as major histocompatibility complex class II, or MHC-II, in patients with Crohn's disease.
"'There are cells that present antigens such as MHC-II, and glia are one of them, but no one had studied their role in the immune system" Gulbransen explained. "Also, one of the major pathways and genes that are altered in IBD is MHC-II, and antigen presentation has been thought of as a dysfunctional mechanism in people with IBD."
"By comparing genetically modified mice incapable of expressing MHC-II on enteric glia to ones with fully functional expression of MHC-II, Aaron teased out the important function these molecules play. Presence of MHC-II antigens during inflammation triggered the signaling and activation of T- and B-cells that in turn activated immune cell subsets involved in anti-inflammatory mechanisms. Without MHC-II, the immune cells that reduce inflammation were much quieter.
"'The takeaway was that a dysfunction in T-cell activation means a person would have more activity towards more bacteria coming across the gut barrier and that drives more inflammation and tissue damage," Gulbransen said.
***
Like their unexpected ability to signal to other neurons through calcium instead of electricity, the researchers discovered that the glia also found an unexpected way to drive the expression of MHC-II and communicate with immune cells—autophagy, or the process of a cell eating components of itself. The glia sacrificed their own bodies to protect enteric neurons from inflammation.
"'That was really interesting because autophagy is a big pathway that is dysregulated in IBD," Gulbransen explained. "If these processes don't work very well, you lose the effective activation of tolerogenic immune cells and get overactivation of the immune system.'"
Comment: Studying a gut disease finds out how processes work employing glia. What I see is the amazing design involved in producing a precisely controlling brain for the gut.
Human evolution: your gut has a big brain
by David Turell , Friday, October 01, 2021, 23:41 (1147 days ago) @ David Turell
More information:
https://medicalxpress.com/news/2021-10-revealing-logic-body-brain.html
"the enteric nervous system is remarkably independent. Intestines could carry out many of their regular duties even if they somehow became disconnected from the central nervous system. And the number of specialized nervous system cells, namely neurons and glia, that live in a person's gut is roughly equivalent to the number.
***
"Neurons are the more familiar cell type, famously conducting the nervous system's electrical signals. Glia, on the other hand, are not electrically active, which has made it more challenging for researchers to decipher what these cells do. One of the leading theories was that glial cells provide passive support for neurons.
"Gulbransen and his team have now shown that glial cells play a much more active role in the enteric nervous system. In research published online on Oct. 1 in the Proceedings of the National Academy of Sciences, the researchers revealed that glia act in a very precise way to influence the signals carried by neuronal circuits. This discovery could help pave the way for new treatments for intestinal illness that affects as much as 15% of the U.S. population.
"'Thinking of this second brain as a computer, the glia are the chips working in the periphery," Gulbransen said. "They're an active part of the signaling network, but not like neurons. The glia are modulating or modifying the signal."
"In computing language, the glia would be the logic gates. Or, for a more musical metaphor, the glia aren't carrying the notes played on an electric guitar, they're the pedals and amplifiers modulating the tone and volume of those notes.
"Regardless of the analogy, the glia are more integral to making sure things are running smoothly—or sounding good—than scientists previously understood. This work creates a more complete, albeit more complicated picture of how the enteric nervous system works. This also creates new opportunities to potentially treat gut disorders."
Comment: We eat, we defecate, all without having to think about it. The proper nutrients are absorbed. This developed in evolution without interspecies or intraspecies conflict, which Darwinism favors as causing evolution. Why is it there? By design.
Human evolution: Neanderthal children developed like us
by David Turell , Wednesday, March 17, 2021, 22:37 (1345 days ago) @ David Turell
A new skeleton of an eight-year-old fossil shows this:
https://www.nationalgeographic.com/science/article/neanderthals-humans-development-brai...
"They used fire; they almost certainly buried their dead; and they seem to have self-medicated with local plants and fungi. One recent study also claims that Neanderthals constructed a mysterious stone circle in a French cave, for unknown symbolic reasons.
"But for years, debate has raged over whether Neanderthals were also humanlike in their physical development. Did their bodies mature quickly in a developmental “fast lane” that primates such as gorillas employ today? Or did Neanderthals develop in a “slow lane” once thought unique to modern humans?
***
"When the team then compared J1's skeleton against thousands of modern human children, J1 most closely resembled today's seven- and eight-year-olds. In short, J1 was growing in a manner indistinguishable from today's children.
"However, Rosas's team says that his skull differs slightly from modern crania. The skull's inner surface bears signs that the bone may have felt pressure from a growing brain, and his brain size was about 88 percent of the average Neanderthal adult's, lacking about a baseball's worth of volume.
"This difference implies that the boy's brain was still growing, the researchers argue. If so, J1's brain development may have been slower than that seen in modern humans, whose brains are fully grown before the age of seven.
***
"After all, adult Neanderthals didn't have cookie-cutter brains. J1's brain was on the smaller side for adults, but hardly without precedent, Ponce de León and Zollikofer say. Some adult Neanderthals had brains even smaller than J1's—and some Neanderthals younger than J1 had bigger brains.
“'While we know El Sidrón’s brain volume at the time of its death, we have no idea about the adult volume that it could have reached,” the two researchers write in a joint email. “However, overall, the paper makes a convincing case for the slow development of the Neanderthals (at least as slow as ours), putting the idea of 'human uniqueness' to a rest!'”
Comment: No question they were more like us than originally thought.
Human evolution: we are entirely improbable
by David Turell , Sunday, August 20, 2023, 19:58 (459 days ago) @ David Turell
A new discussion of probability:
https://inference-review.com/article/a-lonely-universe
"The fact that it took so long suggests that human-like intelligence is difficult to evolve and uncommon.8 This is the basic reasoning behind Snyder-Beattie et al.’s conclusion that intelligent life in the universe is rare.
***
"PREVIOUS ANALYSES HAVE also looked at the emergence of life in conjunction with the emergence of human-like intelligence.9 Motivated by the assumption that four data points are better than two, Snyder-Beattie et al. have extended this earlier work with a Bayesian analysis of not only the timing of abiogenesis and the evolution of intelligence, but also the timing of two other major transitions: eukaryogenesis and the evolution of sexual reproduction. They conclude that intelligent life is rare in the universe because it took humans such a long time to evolve all four of the assumed prerequisites: abiogenesis, eukaryogenesis, sexual reproduction, and intelligence itself. Their Bayesian exploration of this result includes varying the timing of abiogenesis over a relatively wide range—between 4.3 and 3.5 billion years ago—and computing the effect of discovering that life emerged twice on earth.10 They found that their conclusion no longer holds if life emerged twice; or if abiogenesis occurred earlier, say, within ~10 million years of habitability; or if the habitable lifetime of the earth is 10 times longer than expected.
"Recent exoplanet studies strongly suggest that every star has some kind of planetary system and that earth-like planets are likely common in such systems.12 The earth may well be representative of a very large group of wet, rocky planets. But what about atmospheric composition, ocean volume, plate tectonics, spin period, orbital period, obliquity, the presence of a large moon, and the timing of large impacts? If the emergence and evolution of life are dependent on some of these additional details, the number of earth-like planets could be quite small.
***
"...the Snyder-Beattie et al. result depends on the assumption that “intelligent life elsewhere requires analogous evolutionary transitions.” The validity of the Snyder-Beattie et al. result, among others,15 is dependent on the assumption that the major transitions that characterize our evolution happen elsewhere.
***
"In our lineage, eukaryogenesis occurred about two billion years ago and the transition to sexual reproduction about a billion years ago. The transition to intelligence is much more recent and its timing depends on how intelligence is defined. The transition to human-like intelligence or technological intelligence occurred only about 100,000 years ago and is species-specific. The latter trait is strong evidence we should not expect to find it elsewhere.
***
"IS IT REASONABLE to argue that among the features of life on earth, the most likely to appear in life elsewhere are those that have evolved independently many times, such as complex multicellularity, eyes, wings, and canines?20 Not really. These examples of convergent evolution have only occurred within a unique eukaryotic branch that represents a tiny fraction of the diversity of life on earth. The absence of these features elsewhere in the tree of life suggests that eukaryote evolution brought with it fundamental and deeply homologous adaptations necessary for the emergence of these features. If eukaryogenesis were a convergent feature of evolution, we would expect it to have evolved on multiple occasions among the hundreds of independent major lineages. It did not. As a result, we have no evidence that eukaryogenesis is likely to appear outside our own tree of life. The same can be said for the two other major transitions that occurred during the evolution of our lineage. These transitions did not occur in any of the hundreds of non-eukaryotic lineages. Eukaryogenesis, sexual reproduction,21 and human-like intelligence evolved only in our own lineage. (my bold)
"The evolutionary lineages in the universe closest to our own lineage are those found here on earth. And since none of them underwent the three major transitions that happened in our lineage, we have no reason to think they might occur elsewhere. Attempting to compute the probability of human-like intelligence elsewhere based on our lineage is akin to analyzing the evolution of the English language on earth and trying to use the timing of the Great Vowel Shift to estimate its timing on other planets. The quirky, contingent, and self-referential nature of biological evolution means that, like history, it does not lend itself to being modeled using the more deterministic probabilities that physicists and chemists are used to dealing with."
comment: this analysis stresses that the uniqueness of our single evolutionary line tends to negate the proposition life is elsewhere, especially life like human. This is absolutely parallel to Adler's position that the presence of unique humans proves God. It is all in your point of view, isn't it? The original work discussed:
Human evolution: Ardipithecus ramidus.
by David Turell , Thursday, February 25, 2021, 23:12 (1365 days ago) @ David Turell
Perhaps more chimp like:
https://www.newscientist.com/article/2269038-earliest-human-ancestors-may-have-swung-on...
"In popular thinking, humans are often imagined to have evolved from a chimpanzee-like ape, but many researchers now challenge this idea – particularly in light of fossil evidence from A. ramidus that was published in 2009. One well-preserved individual – nicknamed Ardi – had bones that suggested it typically walked along branches like a monkey rather than swinging below them like a chimp. This hinted that our last common ancestor with chimps also walked along branches, and that chimps evolved to swing and knuckle-walk after they branched off from hominins.
"Thomas C. Prang at Texas A&M University and his colleagues disagree with this conclusion. They have taken the measurements of Ardi’s hands reported in 2009 and compared them with 416 measurements from hands across 53 species of living primates, including chimpanzees, bonobos and humans.
“'The analysis of this hand, one of the earliest hands in the human fossil record, suggests that it is chimpanzee-like, implying that both humans and chimps evolved from an ancestor that was chimp-like,” says Prang.
"They found that Ardi’s metacarpals and phalanges – the bones of the fingers and palms – were similar in size to those of living apes, with relatively large joint and knuckle dimensions. These adaptations are present in existing primates that move around forests by swinging below branches and may have helped the hominin to grasp onto branches, and even knuckle-walk.
“'Ardi also has elongated, more curved finger bones, and we see this increased elongation and curvature in animals that habitually hang from branches,” says Prang.
"Larger-bodied primates tend to hang from branches and climb trees, while smaller-bodied animals, like monkeys, are able to walk along the branches.
“[The study] quite convincingly demonstrates that the Ardipithecus hand has some suspensory adaptations, which I think makes more sense given the body size,” says Tracy Kivell at the University of Kent, UK.
***
"Understanding hand morphology of our earliest human relative brings us one step closer to explaining why humans are so different from our close relatives. This may suggest that the last common ancestor of chimpanzees and humans was relatively chimpanzee-like, before the major evolutionary shift towards bipedalism and hand dexterity.
"Tim White at the University of California, Berkeley, who discovered the A. ramidus fossil and helped describe it in 2009, remains unconvinced. “This is another failed resurrection of the antiquated notion that living chimpanzees are good models for our ancestors,” says White. He says that the Ardipithecus hand, aside from having five fingers and the ability to grasp, wasn’t specifically chimpanzee-like, as he and his colleagues originally reported in 2009.
"Sergio Almécija at the American Museum of Natural History in New York is also largely unconvinced. “We need more Miocene [epoch] ape fossils pre-dating the human-chimp split to test fundamental aspects of our last ancestor with apes,” he says.
Comment: A tempest in a teapot. We came from these fossils later on. We are still theorizing about the common ancestor, still unidentified.
Human evolution: we use less water than apes, monkeys
by David Turell , Friday, March 05, 2021, 18:36 (1357 days ago) @ David Turell
We have a different water control result, using less:
https://phys.org/news/2021-03-humans-evolved-closest-primate-relatives.html
"Our bodies are constantly losing water: when we sweat, go to the bathroom, even when we breathe. That water needs to be replenished to keep blood volume and other body fluids within normal ranges.
"And yet, research published March 5 in the journal Current Biology shows that the human body uses 30% to 50% less water per day than our closest animal cousins. In other words, among primates, humans evolved to be the low-flow model.
***
"'Even just being able to go a little bit longer without water would have been a big advantage as early humans started making a living in dry, savannah landscapes," Pontzer said.
***
"For each individual in the study, the researchers calculated water intake via food and drink on the one hand, and water lost via sweat, urine and the GI tract, on the other hand.
"When they added up all the inputs and outputs, they found that the average person processes some three liters, or 12 cups, of water each day. A chimpanzee or gorilla living in a zoo goes through twice that much.
"Pontzer says the researchers were surprised by the results because, among primates, humans have an amazing ability to sweat. Per square inch of skin, "humans have 10 times as many sweat glands as chimpanzees do," Pontzer said. That makes it possible for a person to sweat more than half a gallon during an hour-long workout—equivalent to two Big Gulps from a 7-Eleven.
"Add to that the fact that the great apes—chimpanzees, bonobos, gorillas and orangutans—live lazy lives. "Most apes spend 10 to 12 hours a day resting or feeding, and then they sleep for 10 hours. They really only move a couple hours a day," Pontzer said.
"But the researchers controlled for differences in climate, body size, and factors like activity level and calories burned per day. So they concluded the water-savings for humans were real, and not just a function of where individuals lived or how physically active they were.
"The findings suggest that something changed over the course of human evolution that reduced the amount of water our body uses each day to stay healthy.
***
"The next step, Pontzer says, is to pinpoint how this physiological change happened.
"One hypothesis, suggested by the data, is that our body's thirst response was re-tuned so that, overall, we crave less water per calorie compared with our ape relatives. Even as babies, long before our first solid food, the water-to-calories ratio of human breast milk is 25% less than the milks of other great apes.
"Another possibility lies in front of our face: Fossil evidence suggests that, about 1.6 million years ago, with the inception of Homo erectus, humans started developing a more prominent nose. Our cousins gorillas and chimpanzees have much flatter noses.
"Our nasal passages help conserve water by cooling and condensing the water vapor from exhaled air, turning it back into liquid on the inside of our nose where it can be reabsorbed.
"Having a nose that sticks out more may have helped early humans retain more moisture with each breath."
Comment: Another way humans are very different from ancestor primates.
Human evolution: fingerprint fine sensitivity
by David Turell , Monday, March 15, 2021, 17:51 (1347 days ago) @ David Turell
The use of our hands in very refined:
https://www.newscientist.com/article/2271320-fingerprint-ridges-carry-nerve-endings-tha...
"Our fingertips have an extraordinarily high sensitivity to touch – and now it looks like that sensitivity might be largely confined to the ridges of our fingerprints.
“'They really help us get very detailed information about what we touch,” says Ewa Jarocka at Umeå University in Sweden.
"Scientists have suspected that our circular, winding fingerprints might have evolved to improve our ability to grip objects by creating better friction, says Jarocka. But she says others have suggested they might contribute to our “very refined sense of touch”.
***
"The results allowed the researchers to map out exactly where on the fingertips the information that was sent to the nerve was collected. These sensitivity hotspots turned out to be very small, each only about 0.4 millimetres wide.
"What’s more, these hotspots followed specific patterns on the fingertips – the same ones as the fingerprint ridges. Regardless of how the researchers moved the dotted card over a finger, its hotspot map stayed the same, suggesting the sensitivity zones were “anchored in the very stable structure” of the ridges themselves, says Jarocka.
“'We have all those multiple hotspots, and each one responds to the details of 0.4 millimetres, which is the approximate width of the [fingerprint] ridge,” she says. “Then our brain receives all that information. This really offers an explanation to how it’s possible that we’re so dexterous and have such a high sensitivity in our fingertips.”
"This doesn’t mean fingerprints might not have other functions as well, however – perhaps including improving grip, says Jarocka. But it does reveal the important role that the ridges play in touch.
“'Now that we know that the single neuron can be so sensitive on such a [precise] scale, we can finally explain how people can be so detail-sensitive,” she says."
Comment: We do not know when fingerprints appeared on our evolution. We are now learning their usefulness. Is this another 'stasis problem' appearing long before we developed fine use like violin playing? I would think so. Another special attribute in advance designed by God
Human evolution: erect penis design
by David Turell , Tuesday, March 23, 2021, 18:36 (1339 days ago) @ David Turell
A necessary component of human life:
https://www.researchgate.net/publication/51253209_The_Functional_Morphology_of_Penile_E...
"Inflatable penises have evolved independently at least four times in amniotes, specifically in mammals, turtles, squamates, and the archosaurs. Males in these lineages therefore share the functional problem of building a penis out of soft and flexible tissues that can increase its flexural stiffness and resist bending during copulation. Research on penile erectile tissues in mammals and turtles shows that these two taxa have convergently evolved an axial orthogonal array of collagen fibers to reinforce the penis during erection and copulation; in both lineages, the collagen fibers in the array are crimped and folded in the flaccid penis. Collagen fiber straightening during erection increases the stiffness of the tissue and allows changes in penile radius that increase its second moment of area: both of these changes increase the flexural stiffness of the penis as a whole. And once erect, axial orthogonal arrays have the highest flexural stiffness of any fiber arrangement. The high degree of anatomical convergence (to the level of microanatomical features) within mammals and turtles suggests that the stiffness requirements for copulation produce an extremely restrictive selective regime in organisms that evolve inflatable penises.
***
"Penile convergence in mammals and turtles does not stop at gross functional similarity; they have converged on a single anatomical design down to the level of specific collagen fiber arrangements. The differences in penile collagen fiber layering that exist between mammals and turtles do not, as of yet, seem to have any functional effect on penile stiffness. It may be that the way the axial orthogonal array is put together is less critical to the problem of increasing penile flexural stiffness than the presence of the array itself."
Comment: I've seen chimp erections in Africa. We certainly inherited the mechanism which is necessary for reproduction in our system. The complex design of the collagen fibers indicates they were designed.
Human evolution: high speed throwing
by David Turell , Friday, March 26, 2021, 15:35 (1336 days ago) @ David Turell
Baseball pitchers can throw at over 100 miles an hour. Why?:
https://theconversation.com/how-humans-became-the-best-throwers-on-the-planet-131189?ut...
"In the 2019 season, nearly 90% of the 281 pitchers who threw more than 1,000 pitches threw fastballs that averaged over 90 mph. The 100 mph fastball – once a newsworthy event – is now relatively common.
"But MLB pitchers aren’t the only expert throwers; most healthy people can throw faster than our much stronger chimpanzee relatives, who max out at around 30 mph. A study of boys from the ages of 8 to 14 who were only moderately trained in throwing could still throw two times faster than chimps.
"So how and why did humans evolve to become expert throwers?
***
"Humans are the only species that can throw well enough to kill rivals and prey. Because throwing requires the highly coordinated and extraordinarily rapid movements of multiple body parts,
***
"our hunter-gatherer ancestors threw darts, knives, spears, sticks and stones at rivals and prey. Even today, stones remain effective weapons; you’ll see protesters heave stones at police and stoning used as a form of punishment in some places.
"Darwin considered the evolution of throwing to be critical to the success of our ancestors. As he wrote in “The Descent of Man, and Selection in Relation to Sex,” it allowed “the progenitors of man” to better “defend themselves with stones or clubs, to attack their prey, or otherwise to obtain food.”
***
"But just because you can throw doesn’t mean you can throw well. Anatomical adaptations like a tall mobile waist that decoupled the hips and thorax allowed for more torso rotation. A laterally oriented shoulder joint that better aligned the main axis of the upper arm with the action of chest muscles allowed for a greater range of motion. Both are necessary for high-speed throwing, and these first appeared together in Homo erectus – the first member of our genus – about 2 million years ago.
***
"Even among men, large size and strength do not always result in faster throwing. Throwing speed is influenced by a variety of factors including the range of motion of the throwing arm and stride length. That’s why relatively svelte pitchers like Tim Lincecum and Pedro Martinez were able to throw faster than most of their taller, stronger and bulkier counterparts.
"Their bodies are the paragons of an evolutionary adaptation that has made humans the best throwers on the planet. If rising pitch speeds are any indication, the skill continues to develop. There are even some who argue that pitchers have become too good – and that it’s high time to move back the mound."
Comment: This is obviously an American article with its baseball slant, but makes the point that humans were constructed to be great throwers which aided their hunting as they were slower runners than their four-legged prey. Apes and monkeys have very different musclebound shoulders and apes cannot even use a hammer. And finally we have the brains to analyze ourselves and develop new techniques to train for faster throwing speeds. God made us very special in many different ways.
Human evolution: our precise tasting mechanism
by David Turell , Monday, April 05, 2021, 01:14 (1326 days ago) @ David Turell
The arrangement of our nasopalate:
https://www.newscientist.com/article/mg24933282-200-how-losing-a-bone-in-our-noses-gave...
"this knowledge tells the story of how we have been led by our noses through evolutionary history, turning from chimp-like primate precursors to modern, dinner-obsessed Homo sapiens.
***
"As primates, our experience of smell and flavour is unusual, in that we experience retronasal aromas – the smells that rise up from our mouths into the backs of our noses. This is because we have lost a long bone, called the transverse lamina, that helps to separate the mouth from the nose.
"The loss had important consequences for olfaction, enabling humans to search out tastes and aromas so complex that we have to associate them with memories in order to individually categorise them all.
"The story of how H. sapiens developed such a sophisticated palate is also, of course, the story of how it contributed to the extinction of hundreds of the largest, most unusual animals on the planet. Delicious is a charming book, but it does have its melancholy side.
"To take one dizzying example, the Clovis people – direct ancestors of roughly 80 per cent of all living Indigenous populations in North and South America – definitely ate mammoths, mastodons, gomphotheres, bison and giant horses. They may also have eaten Jefferson’s ground sloths, giant camels, dire wolves, short-faced bears, flat-headed peccaries, long-nosed peccaries, some tapir species, giant llamas, giant bison, stag moose, shrub-oxen and Harlan’s muskoxen.
“'The Clovis menu,” say the authors, “if written on a chalkboard, would be a tally of a lost world.'”
Comment: Another way in which we are most unusual.
Human evolution: trysting with Neanderthals
by David Turell , Wednesday, April 07, 2021, 21:22 (1324 days ago) @ David Turell
More recently more common than realized:
https://www.sciencenews.org/article/europe-oldest-known-humans-mated-neandertals-dna-fo...
"When some of the earliest human migrants to Europe encountered Neandertals already living there around 45,000 years ago, hookups flourished.
"Analyses of DNA found in human fossils from around that time — the oldest known human remains in Europe — suggest that interbreeding between Homo sapiens and Neandertals, who were on the fast track to extinction, occurred more commonly than has often been assumed, two new studies suggest.
"Genetic evidence in the new reports indicates for the first time that distinct human populations reached Europe shortly after 50,000 years ago. Neandertals interbred with all the groups detected so far, ensuring that some of their genes live on today in our DNA.
***
"Remains of three H. sapiens individuals unearthed in Bulgaria’s Bacho Kiro Cave yielded nuclear DNA containing Neandertal contributions of about 3 to 4 percent, says a team led by evolutionary geneticist Mateja Hajdinjak of the Francis Crick Institute in London. The ancient DNA came from a tooth and two bone fragments radiocarbon dated to between around 43,000 and 46,000 years ago. Stone tools typical of late Stone Age humans were found in the same sediment as the fossils.
***
"If H. sapiens and Neandertals regularly interbred as the latter population neared its demise, then relatively large numbers of incoming humans accumulated a surprising amount of DNA from smaller Neandertal populations, Lalueza-Fox suspects. After 40,000 years ago, additional migrations into Europe by people with little or no Neandertal ancestry would have further diluted Neandertal DNA from the human gene pool, he says.
"Those humans made distinctive stone and bone tools and served as ancestors of present-day Europeans, Hajdinjak suggests. At Bacho Kiro Cave, for instance, newly recovered DNA from a roughly 35,000-year-old H. sapiens bone fragment displays a different makeup than that of the cave’s earlier human inhabitants. This individual contributed genes mainly to later populations in Europe and western Asia, Hajdinjak says."
Comment: Sexual activity always attracts.
Human evolution: more on timing brain development
by David Turell , Friday, April 09, 2021, 22:12 (1322 days ago) @ David Turell
edited by David Turell, Friday, April 09, 2021, 22:25
Our body upright posture developed well before our large brain appeared:
https://www.sciencenews.org/article/ancient-humans-brain-apelike-modern-africa-evolution
"Even after ancient humans took their first steps out of Africa, they still may have possessed brains more like those of great apes than modern humans, a new study suggests.
"For decades, scientists had thought modern humanlike organization of brain structures evolved soon after the human lineage Homo arose roughly 2.8 million years ago. But an analysis of fossilized human skulls that retain imprints of the brains they once held now suggests such brain development occurred much later. Modernlike brains may have emerged in an evolutionary sprint starting about 1.7 million years ago, researchers report in the April 9 Science.
"What sets modern humans apart most from our closest living relatives, the great apes, is most likely our brain. To learn more about how the modern human brain evolved, the researchers analyzed replicas of the brain’s convoluted outer surface, re-created from the oldest known fossils to preserve the inner surfaces of early human skulls. The 1.77-million to 1.85-million-year-old fossils are from the Dmanisi archaeological site in the modern-day nation of Georgia and were compared with bones from Africa and Southeast Asia ranging from roughly 2 million to 70,000 years old.
"The scientists focused on the brain’s frontal lobes, which are linked with complex mental tasks such as toolmaking and language. Early Homo from Dmanisi and Africa still apparently retained a great ape–like organization of the frontal lobe 1.8 million years ago, “a million or so years later than previously thought,” says paleoanthropologist Philipp Gunz at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who did not take part in this study. (my bold)
***
"Future research can investigate what evolutionary pressures might have driven the emergence of modern human–like brain organization. Ultimately such research could reveal how brain reorganization is related to the evolution of language and symbolic thought, says study author Christoph Zollikofer, a paleoanthropologist at the University of Zurich. (my bold)
"But perhaps there were no such pressures, “and this reorganization was a by-product of changes in other areas,” says paleoanthropologist Amélie Beaudet at the University of Cambridge, who wrote a review of this study for the April 9 Science. The only way to answer this question “would be to study more fossils from the time period ranging between the earliest human representatives 2.8 million years ago and Homo after 1.8 million years ago and to reconstruct the contexts in which they were living and evolving.'”
Comment: This article, like dhw, looks for natural pressures to force evolution. Note my bolds: language and symbolic thought took 245,000 years to appear after sapiens first arrived on Earth, but it did appear because our brain was lying around waiting for the ability/use to be found. What makes perfect sense is the early timing: with freed arms and better hands the new hominid could learn to do many new things at the manual level, and later. when given a bigger frontal lobe with which to develop immaterial ideation (at 315,000 years ago), could invent more complex objects with more varied activities. God's planning is obvious.
Human evolution: our special gait
by David Turell , Wednesday, April 14, 2021, 21:30 (1317 days ago) @ David Turell
No other biped walked/walks as we do:
https://www.sciencenews.org/article/first-steps-book-bipedalism-human-evolution-anatomy...
"No other animal moves the way we do. That’s awfully strange. Even among other two-legged species, none amble about with a straight back and a gait that, technically, is just a form of controlled falling. Our bipedalism doesn’t just set us apart, paleoanthropologist Jeremy DeSilva posits; it’s what makes us human.
'There’s no shortage of books that propose this or that feature — tool use or self-awareness, for example — as the very definition of humankind. But much of our supposed uniqueness doesn’t stand up to this tradition. In First Steps, DeSilva takes a slightly different approach. Our way of walking, he argues, set off an array of consequences that inform our peculiar evolutionary history. (my bold)
"Tyrannosaurus and ancient crocodile relatives are trotted out to show how they moved on two legs, thanks to long, counterbalancing tails (SN: 6/12/20). DeSilva stumbles a little here, like arguing that “bipedalism was not a successful locomotion for many dinosaur lineages.” An entire group — the theropods — walked on two legs and still do in their avian guises. But the comparison with dinosaurs is still worthwhile. With no tail, the way we walk is even stranger. “Let’s face it,” DeSilva writes, “humans are weird.” (my bold)
"Instead of presenting a march of progress toward ever-greater bipedal perfection, DeSilva highlights how our ancestors had varied forms of upright walking, such as the somewhat knock-kneed gait of Australopithecus sediba. The way we now walk, he argues, was one evolutionary pathway among many possibilities.
"But walking upright opened up unique evolutionary avenues, DeSilva notes. Freed from locomotion, our arms and hands could become defter at creating and manipulating tools. Our ancestors also evolved a bowl-shaped pelvis to comfortably cradle our viscera. But this arrangement made giving birth more complicated, especially as human infants began to have larger heads that needed to pass through a narrowed birth canal created by this anatomical shift. Such trade-offs, including how debilitating twisted ankles and broken bones can be to humans, may have required our ancestors to care for each other, DeSilva concludes. While that may be a step too far into speculation, he nevertheless makes a compelling case overall. “Our bipedal locomotion was a gateway to many of the unique traits that make us human,” he writes, an evolutionary happenstance that formed the context for how we came to be."
Comment: No question, we are unique in so many ways not explained by any natural theory of evolution. This is only one aspect of our bodies' unusual postures and and our unusual dexterity of how we can make our bodies move.
Human evolution: Neanderthal differences
by David Turell , Monday, April 19, 2021, 19:58 (1312 days ago) @ David Turell
They were built for the northern latitudes:
https://www.realclearscience.com/blog/2021/04/19/neanderthals_were_the_human_species_be...
"'It is well-accepted that Neanderthals appear to be the most cold-adapted of known fossil hominin groups," a team of anthropologists recently wrote in the journal Evolutionary Anthropology.
***
"Consider that while we Homo sapiens spent much of our time on Earth in Africa around the equator, Neanderthals dwelled further north, predominantly in dry, and even polar, climates, as far as northern France, through mountainous Uzbekistan, and even to southern Siberia. In these often harsh environments, they had hundreds of thousands of years to adapt morphologically, physiologically, and behaviorally.
***
"For example, Neanderthals had broad trunks and shortened limbs compared to other hominins, which granted a relatively high body volume with a lower surface area.
"'This would have maximized potential metabolic heat production while minimizing heat loss to the environment," the authors wrote.
"Neanderthals also had tall, broad, and generally large noses.
"'This particular nasal shape is considered adaptive, as a tall, narrow nasal passageway increases mucosal surface area, providing greater ability to warm and moisten cold-dry air typical of cold climates," Ocobock and her colleagues explained.
"Lastly, in terms of morphology, Neanderthals had sizable skeletons, hinting at prodigious muscle mass. Muscle produces more heat than fatty tissues, but is also more energetically expensive.
"That's where diet factored in. Given Neanderthals' muscled frames, they likely had much higher metabolisms than other hominins. This demanded calories. A great source of calories is large-bodied game. Deer, ibex, wild boar, aurochs, and occasionally mammoth and woolly rhinoceros, were some of their frequent fare. All of this protein consumption likely boosted their metabolisms even more, thus making their bodies produce more heat.
"Hunting, of course, was a physically demanding activity, involving sprinting, throwing, and carrying heavy loads. All of this exercise, coupled with cooler temperatures, would likely have prompted Neanderthals to develop significant stores of brown fat, which, compared to normal white fat, contains a lot more mitochondria. These cellular 'power plants' are adept at producing heat for warmth.
"While Neanderthals' morphological and physiological adaptations can be reasoned based upon fossil and archaeological evidence, their behavioral adaptations are more of a mystery. We know that Neanderthals made clothing, but scarce evidence of it has survived over the millennia. We also know that they often used caves for shelters and built fires for warmth and cooking. Harder to discern are the cultural and social systems they adopted to thrive in colder climates.
"'Most of these behaviors will be archaeologically invisible to us, though assuredly Neanderthals had systems of food sharing and other cultural buffering mechanisms to cope with the cold," the authors wrote."
Comment: They were around for a long period, but there must be a major difference they had that resulted in only our tribe surviving. I'll stick with our more complex brain which allowed for more inventive concepts..
Human evolution: Little foot analyzed
by David Turell , Tuesday, April 20, 2021, 21:21 (1311 days ago) @ David Turell
Older than Lucy, ape-like upper, bipedal legs:
https://www.sciencedaily.com/releases/2021/04/210420092921.htm
"Although other parts of Little Foot, especially its legs, show humanlike traits for upright walking, the shoulder components are clearly apelike, supporting arms surprisingly well suited for suspending from branches or shimmying up and down trees rather than throwing a projectile or dangling astride the torso like humans.
"The Little Foot fossil provides the best evidence yet of how human ancestors used their arms more than 3 million years ago, said Kristian J. Carlson, lead author of the study and associate professor of clinical integrative anatomical sciences at the Keck School of Medicine.
"'Little Foot is the Rosetta stone for early human ancestors," he said. "When we compare the shoulder assembly with living humans and apes, it shows that Little Foot's shoulder was probably a good model of the shoulder of the common ancestor of humans and other African apes like chimpanzees and gorillas."
***
"The Little Foot fossil is a rare specimen because it's a near-complete skeleton of an Australopithecus individual much older than most other human ancestors. The creature, probably an old female, stood about 4 feet tall with long legs suitable for bipedal motion when it lived some 3.67 million years ago. Called "Little Foot" because the first bones recovered consisted of a few small foot bones, the remains were discovered in a cave in South Africa in the 1990s. Researchers have spent years excavating it from its rock encasement and subjecting it to high-tech analysis.
"While not as widely known as the Lucy skeleton, another Australopithecus individual unearthed in East Africa in the 1970s, Carlson said Little Foot is older and more complete.
***
"The scientists compared the creature's shoulder parts to apes, hominins and humans. Little Foot was a creature adapted to living in trees because the pectoral girdle suggests a creature that climbed trees, hung below branches and used its hands overhead to support its weight.
"For example, the scapula, or shoulder blade, has a big, high ridge to attach heavy muscles similar to gorillas and chimpanzees. The shoulder joint, where the humerus connects, sits at an oblique angle, useful for stabilizing the body and lessening tensile loads on shoulder ligaments when an ape hangs beneath branches. The shoulder also has a sturdy, apelike reinforcing structure, the ventral bar. And the collarbone has a distinctive S-shaped curve commonly found in apes.
"Those conclusions mean that the structural similarities in the shoulder between humans and African apes are much more recent, and persisted much longer, than has been proposed, Carlson said.
"'We see incontrovertible evidence in Little Foot that the arm of our ancestors at 3.67 million years ago was still being used to bear substantial weight during arboreal movements in trees for climbing or hanging beneath branches," he said. "In fact, based on comparisons with living humans and apes, we propose that the shoulder morphology and function of Little Foot is a good model for that of the common ancestor of humans and chimpanzees 7 million to 8 million years ago.'"
Comment: The conclusion is obvious: first down from the trees, then later arm and hand dexterity development, and finally brain enlargement followed by brain complexity, driven by what natural force, if any? Noting chimps remained essentially unchanged, why did we bother to keep changing. I will always believe God did it.
Human evolution: another far eastern Hobbit-like Group
by David Turell , Thursday, April 22, 2021, 01:11 (1309 days ago) @ David Turell
In the Philippines in a cave in Luzon:
https://www.nationalgeographic.com/science/article/new-species-ancient-human-discovered...
"Humankind's tangled shrub of ancestry now has a new branch: Researchers in the Philippines announced today that they have discovered a species of ancient human previously unknown to science.
"The small-bodied hominin, named Homo luzonensis, lived on the island of Luzon at least 50,000 to 67,000 years ago. The hominin—identified from a total of seven teeth and six small bones—hosts a patchwork of ancient and more advanced features. The landmark discovery, announced in Nature on Wednesday, makes Luzon the third Southeast Asian island in the last 15 years to bear signs of unexpectedly ancient human activity.
***
"In 2010, Mijares and his colleagues unveiled the 67,000-year-old fossil, which they tentatively suggested belonged to a small-bodied member of Homo sapiens, making it perhaps the oldest sign of our species anywhere in the Philippines at the time. But Mijares suspected that it might actually belong to a new species, maybe even a Luzon analog to H. floresiensis. The team needed more fossils to be sure.
***
"As luck would have it, excavations uncovered two more toe bones along with seven teeth, two finger bones, and part of a femur on return trips to Callao Cave in 2011 and 2015. In all, the remains represent at least three individuals.
"The small fossils' curves and grooves reveal an unexpected mix of both ancient and more advanced traits. The teeth's small sizes and relatively simple shapes, for instance, point to a more “modern” individual, but one upper premolar has three roots—a trait found in fewer than 3 percent of modern humans. And one foot bone resembles those of the ancient australopithecines, a group that includes the famous human relative Lucy, who trekked across Africa roughly three million years ago.
“'I agree with [the] authors that the combination of features is like nothing we have seen before,” says María Martinón-Torres, the director of Spain's National Research Center on Human Evolution.
"New York University anthropologist Shara Bailey, an expert on ancient teeth, notes that South Africa's Homo naledi—discovered by a team including National Geographic grantee Lee Berger—also has features that look both ancient and modern. She takes the two discoveries as a sign that “mosaic” evolution was more common among hominins than once thought.
"Martinón-Torres further suggests that the mix of dental features somewhat resembles that seen in 15,000-year-old hominin remains from Dushan in southern China, which she and her colleagues recently described. Along with H. luzonensis, the discoveries join recent finds hinting that by 12,000 years ago, as the Pleistocene epoch drew to a close, hominins in Asia had a startling amount of diversity.
***
"There's also evidence that H. luzonensis, or another ancient hominin, lived on Luzon even further back in time. In 2018, Mijares and his colleagues announced the discovery of stone tools and a butchered rhinoceros skeleton that are more than 700,000 years old, found not too far from Callao Cave. Because of the time gap between the remains and the tool site, however, it's tough to say whether the stone tool users were predecessors of H. luzonensis or an unrelated hominin.
***
"Another major unknown is how the ancestors of H. luzonensis even reached the Philippines. In 2016, researchers unveiled stone tools on the Indonesian island of Sulawesi that date to between 118,000 and 194,000 years old—or at least 60,000 years older than the island's oldest known modern humans. Taken alongside the remains from Flores and Luzon, the sites suggest that ancient hominin dispersal throughout the region wasn't necessarily as rare—or as accidental—as researchers once thought.
***
"One thing remains clear: Southeast Asia probably was home to more hominin species than current fossils let on. For his part, Mijares is continuing to look for other signs of H. luzonensis, including a current search at Luzon's Biak na Bato National Park, done with support from the National Geographic Society. Through it all, Mijares sees the future for H. luzonensis—and for Asian anthropology—as bright."
Comment: our evolution is convoluted and obviously our ancestors wandered all over the place, even across oceans. But the main line is still erectus to sapiens
Human evolution: genes driving toward sapiens
by David Turell , Monday, April 26, 2021, 20:08 (1305 days ago) @ David Turell
A study identifying how the genome drove toward sapiens:
https://phys.org/news/2021-04-perspective-genomes-archaic-humans.html
"A genome by itself is like a recipe without a chef—full of important information, but in need of interpretation. So, even though we have sequenced genomes of our nearest extinct relatives—the Neanderthals and the Denisovans—there remain many unknowns regarding how differences in our genomes actually lead to differences in physical traits.
"'When we're looking at archaic genomes, we don't have all the layers and marks that we usually have in samples from present-day individuals that help us interpret regulation in the genome, like RNA or cell structure," said David Gokhman, a postdoctoral fellow in biology at Stanford University.
"'We just have the naked DNA sequence, and all we can really do is stare at it and hope one day we'd be able to understand what it means," he said.
***
Starting with 14,042 genetic variants unique to modern humans, the researchers found 407 that specifically contribute to differences in gene expression between modern and archaic humans. In further analysis, they determined that the differences were more likely to be associated with the vocal tract and the cerebellum, which is the part of our brain that receives sensory information and controls voluntary movement, including walking, coordination, balance and speech.
***
"In total, the researchers found 407 sequences that represented a change in expression in modern humans compared to our predecessors. Among that list, genes that affect the cerebellum and genes that affect the voice box, pharynx, larynx and vocal cords seem to be overrepresented.
"'This would suggest some kind of rapid evolution of those organs or some kind of a path that is specific to modern humans," said Gokhman. The next step, he added, would be trying to understand more about these sequences and the roles they played in the evolution of modern humans.
"Even with those unknowns, this technique by itself is a significant advance for evolutionary research, said Petrov.
"'This goes beyond the sequencing of the DNA from the Neanderthal and Denisovan bones. This begins to put meaning on those differences," said Petrov. "It's an important conceptual step from just the sequence—no tissue, no cells—to biological information and will enable many future studies.'" (my bold)
Comment: In my bold is that nasty word 'information'. This new approach is the same as the ENCODE research on modern DNA, trying to note modifying aspects of gene expression which is much more important than just looking at protein coding. The major finding fits what we already knew from archaeology, modern sapiens evolution was on a fast unnatural evolutionary drive. God may have inserted a fast-driving coded process or may have pushed it Himself.
Human evolution: yawning has a real meaning
by David Turell , Monday, April 26, 2021, 20:44 (1305 days ago) @ David Turell
It is not just boredom or sleepiness:
https://www.realclearscience.com/blog/2021/04/26/most_societies_completely_misunderstan...
"In many societies, yawning often gets a bad rap. We stifle yawns in conversation lest our companions deem us uninterested. We swallow them at work meetings so bosses don't think we're unengaged.
"To Cara Santa Maria, a PhD student in clinical psychology, award-winning science communicator, and co-host of The Skeptics' Guide to the Universe podcast, this seems rather backward.
"'Yawning did evolve as this social cue… We think of it as a way to communicate to our kin that we’re safe, that we’re settled, that we can relax," she said on a recent podcast episode.
"'Yet socially, yawning is considered rude," she stated, bemused at the apparent contradiction.
"She's right. It doesn't make any sense.
***
"Most people tend to view yawning one-dimensionally – as a sign of fatigue and particularly boredom. Scientific research has not evinced this narrow notion, instead illuminating other potential functions.
"Santa Maria touched on one of them. Yawning, it seems, is a form of social empathy, a subtle communication that we're feeling what our friends feel. This is why yawns are contagious, and seem to be more contagious amongst friends and family compared to acquaintances or strangers. This infectious quality doesn't just apply to humans, but to all sorts of animals. For example, a recent study found that yawning seems to help lions synchronize their movements.
"Moreover, as Novella noted, yawning is theorized to help keep animals alert, and to remind conspecifics to do so as well.
"One of the most intriguing explanations for yawning is that it helps us thermoregulate, often to keep the brain cool.
"'Serotonin is an important neurotransmitter in the regulation of skin blood flow, and the thermoregulation this blood flow does. Increases of serotonin have been shown to increase body and brain temperatures, a change that causes the body to trigger more yawns, in an attempt to cool itself," Ada McVean wrote for the McGill Office for Science and Society.
"Further support for this idea comes from an interesting correlation: animals with bigger brains tend to yawn longer."
Comment: Interesting take. I still think I do it when sleepy.
Human evolution: self awareness
by David Turell , Thursday, April 29, 2021, 22:54 (1302 days ago) @ David Turell
A new book describing its importance in making us human:
https://science.sciencemag.org/content/372/6541/470?utm_campaign=toc_sci-mag_2021-04-29...
"Given our long-standing interest in selfawareness, it is surprising how little science has traditionally had to say about it. What features of our brains enable us to think about ourselves? What are our strengths and weaknesses in this respect and how do they influence how we decide, learn, and interact? Can we train self-awareness, and how does this improve our performance? In the past three decades, however, research addressing such questions has been picking up speed. In Know Thyself, cognitive neuroscientist Stephen Fleming synthesizes this multifaceted research into an admirably coherent narrative and outlines how the resulting knowledge may be applied to solve societal problems.
"Writing about self-awareness is challenging because concepts such as “self” and “awareness”—let alone the combination thereof—are hard to define. The book does not get lost in this epistemological Bermuda triangle but rather conceptualizes self-awareness as the set of mental and brain processes that keep track of our percepts, thoughts, and actions.
***
"In the end, the book makes a convincing case that self-awareness is a key feature of human existence and that our growing knowledge about it will be important for addressing many of our societal problems. One may quibble that the book somewhat understates this point, because it focuses on metacognition and does not cover our ability to monitor our emotions, another key aspect of self-awareness that has major implications for health and well-being. However, the literature on this topic is so diverse that doing it justice would likely require several additional volumes. As it stands, Fleming's book finally heaves metacognition into a long-deserved place in the scientific spotlight."
Comment: the book doesn't tell us anything new. It makes the usual point. We are exceptional and like nothing else.
Human evolution: so dominant we change ecosystems
by David Turell , Friday, April 30, 2021, 18:24 (1301 days ago) @ David Turell
Wherever we invade everything changes; ecosystems alterations on islands:
https://science.sciencemag.org/content/372/6541/488
"Oceanic islands are among the most recent areas on Earth to have been colonized by humans, in many cases in just the past few thousand years. Therefore, they are important laboratories for the study of human impacts on natural vegetation and biodiversity. Nogué et al. provide a quantitative palaeoecological study of 27 islands around the world, focusing on pollen records of vegetation composition before and after human arrival. The authors found a consistent pattern of acceleration of vegetation turnover after human invasion, with median rates of change increasing by a factor of six. These changes occurred regardless of geographical and ecological features of the island and show how rapidly ecosystems can change and how island ecosystems are set on new trajectories.
"Abstract
Islands are among the last regions on Earth settled and transformed by human activities, and they provide replicated model systems for analysis of how people affect ecological functions. By analyzing 27 representative fossil pollen sequences encompassing the past 5000 years from islands globally, we quantified the rates of vegetation compositional change before and after human arrival. After human arrival, rates of turnover accelerate by a median factor of 11, with faster rates on islands colonized in the past 1500 years than for those colonized earlier. This global anthropogenic acceleration in turnover suggests that islands are on trajectories of continuing change. Strategies for biodiversity conservation and ecosystem restoration must acknowledge the long duration of human impacts and the degree to which ecological changes today differ from prehuman dynamics.
"Globally, human activities dominate ecological systems (1, 2) and are considered the main drivers for accelerating contemporary ecosystem transformation.
***
"...ecological legacies of human arrival on islands may persist for centuries and are often irreversible. An example is Tawhiti Rahi in the Poor Knights archipelago, which is currently uninhabited (19). Immediately after initial arrival by Polynesians in the 13th century, the island’s forest cover was cleared by fire for human habitation and gardens. After a massacre of local Ngatiwai inhabitants on Tawhiti Rahi in 1820, local kaitiaki (guardians) declared the islands wahi tapu (protected by a sacred covenant), after which time there was no subsequent settlement. Despite the island becoming totally reforested within 150 years, the current forest composition is completely different from that of the prehuman period. In contrast to the Poor Knights archipelago, most currently inhabited islands have experienced at least two distinct waves of settlement, each having distinctive signatures of change and leaving increasingly complex legacies
***
"Our results show little indication that these human-affected ecosystems are either similar to or returning to the dynamic baselines observed before human arrival. Therefore, anthropogenic impacts on islands are lasting components of these systems typically involving initial clearance (e.g., using fire) and are compounded by the introduction of a range of introduced species and extinctions of endemic species and ongoing disturbances. This contrasts with turnover after natural disturbances in the prehuman period, when island ecosystems often recovered rapidly to predisturbance states."
Comment: The importance of ecosystems cannot be overemphasized. Living organisms naturally form cooperative systems and our overall dominance upsets them with plant systems, animal systems or combinations. We have severely affected the Earth's evolution.
Human evolution: are we more thirsty?
by David Turell , Thursday, June 17, 2021, 19:19 (1253 days ago) @ David Turell
This author seems to thinks so:
https://www.scientificamerican.com/article/human-evolution-led-to-an-extreme-thirst-for...
"Throughout history people have drastically engineered their environments to ensure access to water. Take the historic Roman city of Caesarea in modern-day Israel. Back when it was built, more than 2,000 years ago, the region did not have enough naturally occurring freshwater to sustain a city. Because of its geographic importance to their colonial rule, the Romans, through extractive slave labor, built a series of aqueducts to transport water from springs as far as 16 kilometers away. This arrangement provided up to 50,000 people with approximately 145 liters of water per capita a day.
"Today cities use vast distribution networks to provide potable water to people, which has led to remarkable improvements in public health. When we have plenty of water, we forget how critical it truly is. But when water is precious, it is all we think about. All it takes is news of a shutoff or contamination event for worries about water insecurity to take hold.
"To understand how water has influenced the course of human evolution, we need to page back to a pivotal chapter of our prehistory. Between around three million and two million years ago, the climate in Africa, where hominins (members of the human family) first evolved, became drier. During this interval, the early hominin genus Australopithecus gave way to our own genus, Homo. In the course of this transition, body proportions changed: whereas australopithecines were short and stocky, Homo had a taller, slimmer build with more surface area. These changes reduced our ancestors' exposure to solar radiation while allowing for greater exposure to wind, which increased their ability to dissipate heat, making them more water-efficient.
"Other key adaptations accompanied this shift in body plan. As climate change replaced forests with grasslands, and early hominins became more proficient at traveling on two legs in open environments, they lost their body hair and developed more sweat glands. These adaptations increased our ancestors' ability to unload excess heat and thus maintain a safe body temperature while moving, as work by Nina Jablonski of Pennsylvania State University and Peter Wheeler of Liverpool John Moores University in England has shown.
***
"Humans have evolved to use less water than chimps and other apes, despite our greater sweating ability, as new research by Herman Pontzer of Duke University and his colleagues has shown.
***
"Experimental studies have demonstrated that water restriction among pregnant rats and sheep leads to critical changes in how their offspring detect bodily dehydration. Offspring born to such water-deprived mothers will be more dehydrated (that is, their urine and blood will be more concentrated) than offspring born to nondeprived mothers before they become thirsty and seek out water. These findings indicate that the dehydration-sensitivity set point is established in the womb.
"Thus, the hydration cues received during development may determine when people perceive thirst, as well as how much water they drink later in life. In a sense, these early experiences prepare offspring for the amount of water present in their environment. If a pregnant woman is dealing with a water-scarce environment and is chronically dehydrated, it may lead to her child consistently drinking less water later in life—a trait that is adaptive in places where water is hard to come by. Much more work is needed to test this theory, however."
Comment: I found this very interesting. Our horses drink abut five gallons a day. And the research cited above says we drink less than chimps and apes
Human evolution: “Ardipithecus ramidus
by David Turell , Thursday, June 17, 2021, 20:34 (1253 days ago) @ David Turell
A very strange pre homo:
https://www.sciencenews.org/article/evolutions-bad-girl
"Ardi’s unusual mix of apelike and monkeylike traits demolishes the long-standing assumption that today’s chimpanzees provide a reasonable model of either early hominids or the last common ancestor of people and chimps — an ancestor which some scientists suspect could even have been Ardi, if genetics-based estimates of when the split occurred are borne out.
"Second, the team concludes, Ardi trashes the idea that knuckle-walking or tree-hanging human ancestors evolved an upright gait to help them motor across wide ancient savannas. Her kind lived in wooded areas and split time between lumbering around on two legs hominid-style and cruising carefully along tree branches on grasping feet and the palms of the hands.
"One member of White’s team argues for a controversial possibility: that two-legged walking evolved because Ardipithecus males had small canine teeth. Many living and fossil male apes fight for mates by wielding formidable canines, but Ardi’s male counterparts had to band together and forage over long distances to obtain mates, his thinking goes.
'In a third slap at scientific convention, Ardi fits a scenario in which a few closely related hominid lineages preceded the larger-brained Homo genus that emerged around 2.4 million years ago, White says. In contrast, many anthropologists think of hominid evolution as a bush composed of numerous lineages that, for the most part, died out.
***
"Ardi sports a peculiar skeletal medley that pushes chimps and gorillas out of the evolutionary spotlight, says anthropologist Owen Lovejoy, a member of White’s team. Ardi’s ancient remains indicate that the last common ancestor of humans and chimps must not have looked much like living chimps, as many researchers have assumed, asserts Lovejoy, of Kent State University in Ohio.
"Since a split 8 million years ago or so, chimps and gorillas have evolved along evolutionary paths that eventually produced specialized traits such as knuckle-walking, he says.
"In his opinion, Ardi indicates that a human-chimp ancestor had monkeylike limb proportions and feet, a flexible and unchimplike lower back, and an ability to move along tree branches on all fours, rather than swinging chimp-style from branch to branch and hanging by outstretched arms.
“'Ardipithecus, not living chimps, offers a remarkably good perspective on the last common ancestor,” he says. “We can’t modify the truth to make chimps more important.”
"That conclusion leaves some scientists unimpressed. “It’s way too early to claim that we know what the last common ancestor looked like without actually finding its fossils,” remarks anthropologist Brian Richmond of George Washington University in Washington, D.C.
"Richmond holds that Ardi lived several million years after the last common ancestor, plenty of time for her kind to have evolved substantial skeletal changes.
"And those changes may not have been as substantial as White’s team claims, adds Richmond. Ardi’s curved toes, wide big toe and large body correspond pretty well to chimps, in his opinion.
"Other fossil evidence suggests that hominids came from a climbing and knuckle-walking ape ancestor that was unlike Ardi, Richmond argues."
Comment: An interesting variation. We still do not know how we exactly evolved. I think I presented this before, but search showed no reference.
Human evolution: no time for chance
by David Turell , Saturday, June 19, 2021, 15:12 (1251 days ago) @ David Turell
Using necessitated mutational genetic timetables, there is not enough elapsed time to explain human evolution:
http://voxday.blogspot.com/2021/06/neo-darwinism-is-dead.html
"Some of you will recall that I thoroughly, and in some detail, demonstrated the way in which, according to the present scientific understanding of astrophysics, genetic biology, and mathematics, the modern Neo-Darwinian synthesis of the theory of evolution by (mostly) natural selection is impossible, caught as it is between the Scylla of a fixed amount of time and the Charybdis of the number of fixed mutations required to take place in the evolution between one historical species and a present species.
"To put it in the most simple terms that even a biologist should be able to follow, if we are told that a football team has gained 1,500 yards on the ground while averaging three yards per rushing play, and we know that the maximum number of offensive plays per team per game is 84, then we know, beyond any shadow of a doubt, that the yards reported were not gained in a single 60-minute game. They could not have been. It is impossible.
***
"In like manner, the number of fixed mutations that are presently observed to distinguish two species, whether we contemplate modern Man and the Chimpanzee–Human last common ancestor (CHLCA) or the dog and one of the therapsids, are considerably - CONSIDERABLY - in excess of the maximum amount of time that could have passed since the speciation process is believed to have begun. There is only one defense against this straightforward mathematical observation, and that is the idea that enough parallel mutations happened very, very quickly to significantly reduce the average time per fixed mutation to permit it to happen in the intervening time period.
"The problem here, of course, is that the numerical gap that needs to be filled is so large that if that were the case, then these mutations would be have to be happening so rapidly, and fixing in parallel so quickly, that we could observe evolution by natural selection happening in real time all the time.
"And, as predicted, the new advances in genetic science combined with new archeobiological discoveries are methodically reducing the already insufficient time in which evolution had to go from point A to point Z.
"Peştera Muierii woman is related to Europeans, but she is not a direct ancestor
"Reduced diversity in Europe caused by Last Glaciation, not out-of-Africa bottleneck
"Genetic load appears indifferent across 40,000 years of European history
"New DNA extraction approach recovers up to 33 times more DNA from ancient remains
"Summary:
"Few complete human genomes from the European Early Upper Palaeolithic (EUP) have been sequenced. Using novel sampling and DNA extraction approaches, we sequenced the genome of a woman from “Peştera Muierii,” Romania who lived ∼34,000 years ago to 13.5× coverage. The genome shows similarities to modern-day Europeans, but she is not a direct ancestor. Although her cranium exhibits both modern human and Neanderthal features, the genome shows similar levels of Neanderthal admixture (∼3.1%) to most EUP humans but only half compared to the ∼40,000-year-old Peştera Oase 1. All EUP European hunter-gatherers display high genetic diversity, demonstrating that the severe loss of diversity occurred during and after the Last Glacial Maximum (LGM) rather than just during the out-of-Africa migration. The prevalence of genetic diseases is expected to increase with low diversity; however, pathogenic variant load was relatively constant from EUP to modern times, despite post-LGM hunter-gatherers having the lowest diversity ever observed among Europeans.
"Translation: there was even more genetic diversity among early humans than previously believed, which further increases the required rate of time per fixed mutation.
"Or to put the point in even more simple terms, it is mathematically more credible to claim that you drove from New York to Los Angeles in a 1976 Cadillac Eldorado in one hour on a single tank of gas than to claim that any modern mammal evolved from the first crown group mammal in the amounts of time currently estimated."
Comment: This summary of of genetic speed in evolutionary studies covers the fact that I have not presented much of this in the past. The papers are filled with higher math formulas that I cannot follow and the conclusions seem to cone out of thin air. This presentation is not that, but quite clear. Mutational changes seem driven and compressed into less time than current estimated mutation rates allow. And this can be applied to the Cambrian complexity gap in spades. Totally new complex body forms with a full complement of organ systems, including eyes with complex bifocal lenses.
Human evolution: all those in the Denisovan cave
by David Turell , Thursday, June 24, 2021, 15:12 (1246 days ago) @ David Turell
At various stages Denisovans, Neanderthals and sapiens were there:
https://www.sciencemag.org/news/2021/06/ancient-siberian-cave-hosted-neanderthals-denis...
"A decade ago, anthropologists shocked the world when they discovered a fossil pinkie bone from a then-unknown group of extinct humans in Siberia’s Denisova Cave. The group was named “Denisovans” in its honor. Now, an extensive analysis of DNA in the cave’s soils reveals it also hosted modern humans—who arrived early enough that they may have once lived there alongside Denisovans and Neanderthals.
***
"Humans—including Neanderthals and Denisovans—are known to have occupied Denisova Cave for at least 300,000 years. Among the eight human fossils unearthed there are the pinkie, three bones from Neanderthals, and even one from a child with one Neanderthal and one Denisovan parent. The cave also contains sophisticated stone tools and jewelry at higher, later levels. But no modern human fossils have been found there. Those artifacts, extensive studies of DNA from these bones, and even one early study of DNA from soils have cemented the cave’s importance for piecing together human evolution.
***
"Working with another team of experts who had previously dated the layers of the cave, the researchers dug out 728 soil samples. After 2 years of analysis, in which they isolated and sequenced the samples, the researchers found human DNA in 175 of them. That makes the study “the largest and most systematic of its kind,” says Katerina Douka, an archaeological scientist at the Max Planck Institute for the Science of Human History who was not involved in the work.
***
"The data reveal a complex history of human and animal habitation, with different groups moving in and out of the cave over time, Zavala and her colleagues report today in Nature. Their work confirms that Denisovans were the cave’s first human inhabitants, about 300,000 years ago. They disappeared 130,000 years ago, only to be followed by a different group of Denisovans, who likely made many of the stone tools, some 30,000 years later. Neanderthals appeared on the scene about 170,000 years ago, with different groups using the cave at various points in time, some overlapping with the Denisovans.
"The last to arrive were modern humans, who showed up about 45,000 years ago. The soil layer that corresponds with that period contained DNA from all three human groups, the researchers report. “The time periods [of each layer] are quite large, so we can’t concretely say if they overlapped or not,” Zavala says. But, Douka adds, “I cannot think of another site where three human species lived through time.”
"Given the jewelry and sophisticated artifacts in later layers, some researchers had suspected moderns had been there. But no one knew they had arrived as early as 45,000 years ago—and overlapped with both of our archaic cousins. “It suggests a more complicated interplay between archaic and modern humans,” says Ron Pinhasi, an evolutionary anthropologist at the University of Vienna who was not involved with the work."
Comment: No surprises. Caves are great natural shelters.
Human evolution: sleep length genetically controlled
by David Turell , Thursday, June 24, 2021, 19:21 (1246 days ago) @ David Turell
Study shown in mice and in this family:
https://edition.cnn.com/2021/06/22/health/short-sleep-gene-wellness-scn/index.html?utm_...
"For as long as he can remember, Brad Johnson knew he was different.
"'I've never been normal when it came to sleep," Brad told CNN. "Other people, even some of my siblings, slept eight, nine, 10 hours a night. I just couldn't do it, it was physically impossible. If you paid me a million dollars to sleep eight hours tonight, I couldn't."
It didn't seem to matter what time he went to bed, how little sleep he'd had or how tired he was from the day's activities, both as a child and now, at age 64, Brad said.
'I'd get five hours and be done. Up, ready to go," he said. "I wasn't groggy, I wasn't tired, just ready to roll and go."
***
"Brad wasn't alone. In his large Mormon family of eight kids, his two older brothers Rand and Paul also woke early and suffered no ill effects. In fact, the boys were amazingly productive, driven to wake and immediately tackle life with gusto and high spirits.
"In the dark, wee hours of those mornings the boys practiced basketball, did homework and hobbies and read everything they could get their hands on.
"'Everyone in our family loves to read," Brad said. "We are voracious, voracious readers."
***
"The birth of the idea that people might sleep for only five hours and bypass the ill effects of sleep deprivation was sheer "serendipity," said neurology professor Ying-Hui Fu, who conducts sleep gene research at the Weill Institute for Neurosciences at the University of California, San Francisco.
***
"The hunt was on for more people -- like the Johnsons -- who fit that pattern. By 2009, the team published their first finding: There was a mutation in the gene DEC2 which caused short sleepers to stay awake longer. Since then, the team has discovered two more genes -- an ADRB1 mutation and a NPSR1 mutation -- which alter neurotransmitters in the human brain to create short sleep.
"During each of these studies, the team bred mice with the same genetic mutations to test the gene's function. The results: Genetically-altered mice also slept for fewer hours, with no negative health effects.
***
"Sleep is the time when the body consolidates memories, and cleanses the brain of neurotoxins. Without the necessary REM and deep wave sleep that a full eight hours of slumber brings, most people struggle with memory recall, Fu said.
"'Yet mice, and presumably humans with the short sleep gene mutation, remember quite well on little sleep, whereas most people won't remember much of anything if you deprive them of sleep," she said."
Comment: Not a surprising finding. I reviewed the mouse study paper and it added nothing to this story.
Human evolution: a new hominin ancestor in Israel
by David Turell , Thursday, June 24, 2021, 19:54 (1246 days ago) @ David Turell
A probable Neanderthal ancestor:
https://www.newscientist.com/article/2282141-newly-identified-ancestor-of-neanderthals-...
"A previously unknown group of ancient humans lived in what is now Israel for hundreds of thousands of years. They lived alongside modern humans for some of that time, and the two groups may have interacted and learned skills from each other.
"The newly discovered people were the ancestors of the Neanderthals, who later roamed Europe and western Asia, argues the team behind the work. If that is true, Neanderthals originated in western Asia, not in Europe as many researchers have previously suspected.
***
"The team found parts of the roof of a hominin skull and a near-complete jawbone. “We believe it’s of the same individual,” says Hila May, also at Tel Aviv University, another author of the work.
***
"The sediments in which the bones were found are between 140,000 and 120,000 years old. Our species had emerged in Africa by this time, and made some forays outside: Homo sapiens specimens from 210,000 years ago have been found in Greece, and a seemingly more sustained population existed in the Israel region from at least 177,000 years ago. But H. sapiens wasn’t the only hominin: Europe and western Asia were home to the Neanderthals (Homo neanderthalensis), while eastern Asia was home to a related group called the Denisovans.
"To find out if the Nesher Ramla hominin belonged to one of these groups, the team compared the shapes of the bones with those of dozens of other hominin remains. “It was easy to say that it’s not Homo sapiens,” says May. The skull was low and flat, rather than rounded and tall, and the jawbone lacked the chin that is characteristic of our species.
"But it didn’t fit any of the other groups either. In some ways, the bones resembled Neanderthal ones, but in others they looked like those of hominins that lived earlier in prehistory.
***
"The team argues that all these bones should be considered together as a new hominin group, which lived in western Asia between 420,000 and 120,000 years ago. The hominin at Nesher Ramla was “a residue or survivor of this source population”, argues Sarig.
***
"A Neanderthal who lived in northern Europe 124,000 years ago had some H. sapiens DNA, around 80,000 years before modern humans got there. This could be explained if modern humans interbred with Nesher Ramla Homo in western Asia and some of the resulting hybrids interbred with European Neanderthals.
"The Nesher Ramla Homo may also explain other unusual fossils. The bones from the caves of Skhul and Qafzeh in Israel have sometimes been classed as H. sapiens, but don’t look typical of our species. The team suggests they are actually the result of interbreeding between H. sapiens and Nesher Ramla Homo."
Comment: All a morphological discussion which can be deciphered if DNA can be analyzed in the future. May not enlarge the hominin bush. Another article with great pictures of the findings:
https://phys.org/news/2021-06-nesher-ramla-homo-fossil-discovery.html
Human evolution: possible new hominin species
by David Turell , Friday, June 25, 2021, 18:13 (1245 days ago) @ David Turell
One strange skull from Northern china:
https://www.nationalgeographic.com/science/article/dragon-man-fossil-skull-may-represen...
"The strange skull appeared soon after the Japanese invaded northeast China in the early 1930s. A team of locals was raising a bridge near Harbin, a city in China’s northernmost province, when one of the workers stumbled on a surprise in the river mud. The nearly complete human skull had an elongated cranium from which a heavy brow bone protruded, shading the gaping squares that once housed eyes.
"And then there was the skull’s unusual size: "It's enormous," says paleoanthropologist Chris Stringer of London's Natural History Museum.
***
"Now, nearly 90 years later, a study published in the journal The Innovation makes the case that this skull represents a new human species: Homo longi, or the Dragon Man.
"Two additional studies reveal that the stunningly preserved cranium likely came from a male that died at least 146,000 years ago. Its mashup of both ancient and more modern anatomical features hints at a unique placement on the human family tree.
"'I’ve held a lot of other human skulls and fossils, but never like this," says paleoanthropologist Xijun Ni of the Chinese Academy of Sciences, who is an author of all three studies.
"Based on the shape and size of the Harbin skull, as it's often called, and comparison to other known fossils, the researchers posit that it’s closely related to several other perplexing human fossils, from this same time period, that have been found across Asia. The researchers’ analysis suggests all these fossils belong to a group that is closely related to our own species—perhaps even more so than the Neanderthals.
***
"'We forget, even as anthropologists, that it’s really weird for us to be the only hominins left alive," says Laura Buck, biological anthropologist at Liverpool John Moores University, who was not part of the study team. (my bold)
***
"If not its own species, what was the Dragon Man? Stringer points to a similar mix of modern and more ancient traits in a fossil called the Dali cranium, which the new study categorized in the same group as the Harbin skull. Found in Shaanxi Province in Northwest China, this skull is considered its own species, Homo daliensis.
"'There is already a bit of an inflation of species names in anthropology," adds Bence Viola, a paleoanthropologist at the University of Toronto, who was not part of the study team. He thinks it’s preferable to group the skull with H. daliensis, or leave the species unnamed, rather than coining a new species moniker."
Comment: Variations in form should be considered rather than multiple species, but even so the hominin bush is big, and could be the result of different types interbreeding and hybridizing. Note my bold. I'm not surprised because of our probable superior brain.
Human evolution: hands more like gorilla than chimp
by David Turell , Monday, June 28, 2021, 17:56 (1242 days ago) @ David Turell
We are not chimps despite the similar DNA totals of bases:
https://www.sciencemag.org/news/2015/07/humans-have-more-primitive-hands-chimpanzees
"The human hand is a marvel of dexterity. It can thread a needle, coax intricate melodies from the keys of a piano, and create lasting works of art with a pen or a paintbrush. Many scientists have assumed that our hands evolved their distinctive proportions over millions of years of recent evolution. But a new study suggests a radically different conclusion: Some aspects of the human hand are actually anatomically primitive—more so even than that of many other apes, including our evolutionary cousin the chimpanzee. The findings have important implications for the origins of human toolmaking, as well as for what the ancestor of both humans and chimps might have looked like.
"Humans and chimps diverged from a common ancestor perhaps about 7 million years ago, and their hands now look very different. We have a relatively long thumb and shorter fingers, which allows us to touch our thumbs to any point along our fingers and thus easily grasp objects. Chimps, on the other hand, have much longer fingers and shorter thumbs, perfect for swinging in trees but much less handy for precision grasping. For decades the dominant view among researchers was that the common ancestor of chimps and humans had chimplike hands, and that the human hand changed in response to the pressures of natural selection to make us better toolmakers.
"But recently some researchers have begun to challenge the idea that the human hand fundamentally changed its proportions after the evolutionary split with chimps. The earliest humanmade stone tools are thought to date back 3.3 million years, but new evidence has emerged that some of the earliest members of the human line—such as the 4.4-million-year-old Ardipithecus ramidus (“Ardi”)—had hands that resembled those of modern humans rather than chimps, even though it did not make tools. And back in 2010, a team led by paleoanthropologist Sergio Almécija, now at George Washington University in Washington, D.C., began arguing that even earlier human relatives, dating to 6 million years ago—very soon after the human-chimp evolutionary split—already had humanlike hands as well. This even included the ability to press the thumb against the fingers with considerable force, a key aspect of precision gripping.
***
"The researchers found that the hand of the common ancestor of chimps and humans, and perhaps also earlier ape ancestors, had a relatively long thumb and shorter fingers, similar to that of humans today. (Gorillas, which spend most of their time on the ground and not in trees, have similarly shaped hands.) Thus, the human hand retains these more “primitive” proportions, whereas the elongated fingers and shorter thumbs of chimps, as well as orangutans, represent a more specialized and “derived” form ideal for life in the trees, the team reports today in Nature Communications.
***
“'It’s good to see that some of the implications of Ardi”—that the common ancestor of chimps and humans was not chimplike—“are being noticed,” adds Owen Lovejoy, an anatomist at Kent State University in Ohio and member of the team that studied this early member of the human line. Rather than being a good model for this common ancestor, Lovejoy says, today’s chimps are “highly specialized” for a fruit-eating life high up in the trees.
"But the study is not likely to receive a warm welcome from researchers who think the common ancestor of chimps and humans was indeed more chimplike. The team “build[s] an evolutionary scenario based on one data point, bony proportions of hands, with the underlying assumption that they tell a story,” says Adrienne Zihlman, a primatologist at the University of California, Santa Cruz. Zihlman argues that the hands alone provide researchers with only a very limited view of what the common ancestor was like. “This paper serves as a poster child for what is wrong with a lot of work in paleoanthropology.'”
Comment: Once again, we are not chimp offspring's.
Human evolution: Dragon man may be Denisovan
by David Turell , Thursday, July 01, 2021, 21:16 (1239 days ago) @ David Turell
I've now seen two articles that make the claim, as an educated guess:
Social interactions among animals mediate essential behaviours, including mating, nurturing,
https://science.sciencemag.org/content/373/6550/11.full
"Summary
Almost 90 years after a Chinese bridge builder discovered a remarkably complete human skull and hid it in a well, Chinese scientists are now introducing it as "Dragon Man," the newest member of the human family, who lived more than 146,000 years ago. In three papers in the year-old journal The Innovation, paleontologist Qiang Ji of Hebei GEO University and his team describe the skull and argue it represents a new species that is a sister group to Homo sapiens, even closer kin to us than were the Neanderthals. Other researchers question that idea. But they suspect the large skull, which the team calls H. longi (long means dragon in Mandarin), has an equally exciting identity: They think it may be the long-sought skull of a Denisovan, an elusive human relative from Asia known chiefly from DNA."
***
"Instead, she and others say, Dragon Man is probably a Denisovan, an extinct cousin of the Neanderthals. To date, the only clearly identified Denisovan fossils are a pinkie bone, teeth, and a bit of skull bone from Denisova Cave in Siberia, where Denisovans lived off and on from 280,000 to 55,000 years ago. But the enormous, “weird” molar from the new skull fits with the molars from Denisova, says Bence Viola, a paleoanthropologist at the University of Toronto, who analyzed the Denisova fossils with Hublin. The link with the Xiahe Cave jawbone, if correct, would strengthen the case, as a protein from that fossil as well as ancient DNA in the sediments of the cave strongly suggest it was a Denisovan.
"The authors concede that their critics have a point. “I think it probably is a Denisovan,” says Chris Stringer, a paleoanthropologist at London's Natural History Museum and co-author on two of the papers. DNA analysis of the new skull could resolve the issue. But the team says it does not want to risk destroying the tooth or other bone to get DNA or protein.
"If the new skull is indeed from a Denisovan, the team's claim to have found the closest human ancestor would crumble. DNA studies have established that Denisovans and Neanderthals formed sister groups, more closely related to each other than to H. sapiens. But Dragon Man would still be a landmark fossil. Viola hopes researchers can analyze its DNA, so that “I can finally look into the eyes of a Denisovan.'”
Comment: Exciting news if true. Hope for DNA recovery.
Human evolution: Denisovan DNA in Southeast Asia
by David Turell , Thursday, August 12, 2021, 21:12 (1197 days ago) @ David Turell
Averaging five percent:
https://www.sciencenews.org/article/indigenous-people-philippines-denisovan-dna-genetics
"Denisovans are an elusive bunch, known mainly from ancient DNA samples and traces of that DNA that the ancient hominids shared when they interbred with Homo sapiens. They left their biggest genetic imprint on people who now live in Southeast Asian islands, nearby Papua New Guinea and Australia. Genetic evidence now shows that a Philippine Negrito ethnic group has inherited the most Denisovan ancestry of all. Indigenous people known as the Ayta Magbukon get around 5 percent of their DNA from Denisovans, a new study finds.
"This finding fits an evolutionary scenario in which two or more Stone Age Denisovan populations independently reached various Southeast Asian islands, including the Philippines and a landmass that consisted of what’s now Papua New Guinea, Australia and Tasmania. Exact arrival dates are unknown, but nearly 200,000-year-old stone tools found on the Indonesian island of Sulawesi may have been made by Denisovans. H. sapiens groups that started arriving around 50,000 years ago or more then interbred with resident Denisovans.
***
"Papua New Guinea highlanders — estimated to carry close to 4 percent Denisovan DNA in the new study — were previously thought to be the modern record holders for Denisovan ancestry. But the Ayta Magbukon display roughly 30 percent to 40 percent more Denisovan ancestry than Papua New Guinea highlanders and Indigenous Australians, Jakobsson says.
***
"The new report underscores that “still today there are populations that have not been fully genetically described and that Denisovans were geographically widespread,” says paleogeneticist Cosimo Posth of the University of Tübingen in Germany, who was not part of the new research.
***
"Larena and Jakobsson’s findings “further increase my suspicions that Denisovan fossils are hiding in plain sight” among previously excavated discoveries on Southeast Asian islands, says population geneticist João Teixeira of the University of Adelaide in Australia, who did not participate in the new study.
***
"Geographic ancestry patterns on Southeastern Asian islands and in Australia suggest that this region was settled by a genetically distinct Denisovan population from southern parts of mainland East Asia, Teixeira and his colleagues reported in the May Nature Ecology & Evolution."
Comment: Found in Siberia and now everywhere in Asia. Hum an evolution is a large complex bush. To forestall dhw, I have no idea why God wanted so many forms before we conquered all.
Human evolution: role of growth hormone receptor gene
by David Turell , Sunday, September 26, 2021, 18:52 (1152 days ago) @ David Turell
A confused article with a very narrow view:
https://phys.org/news/2021-09-gene-tied-growth-scientists-glimmers.html
A new study delves into the evolution and function of the human growth hormone receptor gene, and asks what forces in humanity's past may have driven changes to this vital piece of DNA.
The research shows, through multiple avenues, that a shortened version of the gene—a variant known as GHRd3—may help people survive in situations where resources are scarce or unpredictable.
***
Here's the story the study tells: GHRd3 emerged about 1-2 million years ago, and was likely the overwhelmingly predominant version of the gene in the ancestors of modern humans, as well as in Neanderthals and Denisovans.
Then, "In the last 50,000 years or so, this variant becomes less prevalent, and you have a massive decrease in the frequency of this variant among East Asian populations we studied, where we see the estimated allele frequency drop from 85% to 15% during the last 30,000 years," says University at Buffalo evolutionary biologist Omer Gokcumen. "So the question becomes: Why? Was this variant favored in the past, and it fell out of evolutionary favor recently? Or is what we are observing just a blip among the complexity of genomes?" (my bolds)
The research provides new insights into the function of GHRd3 that may help explain why these evolutionary changes occurred, demonstrating that the variant may be useful in coping with nutritional stress.
"We think that this variant is beneficial where there are periods of starvation, which was the case for most of human evolution," says Gokcumen, Ph.D., associate professor of biological sciences in the UB College of Arts and Sciences. With regard to GHRd3's waning prominence in recent human history, he speculates that, "Maybe the rapid technological and cultural advances over the past 50,000 years have created a buffer against some of the fluctuations in resources that made GHRd3 so advantageous in the past."
***
The growth hormone receptor gene plays a major role in controlling the body's response to growth hormone, helping to activate processes that lead to growth.
To study the gene's evolutionary history, scientists looked at the genomes of many modern humans, as well as those of four archaic hominins—three Neanderthals from different parts of the world, and one Denisovan. (All four had the GHRd3 variant.)
Comment: A very strange set of conclusions from this narrow study of one gene. Certainly my first bold is true. More food became available as more modern times appeared with a better food supply. The second bold covers the magical effect Darwinist scientists ascribe to evolution magically conducting its purposes. My point in this presentation is another observation about human height size: in 14th century England the doors were so short, modern folks stoop to enter them. American antique clothing from the 17-18 centuries produces the same short height results. So my question is with less activator genes around, what lead to our current taller heights? The activator's effect is the opposite.
Human evolution: pre-human foot prints
by David Turell , Monday, October 11, 2021, 18:50 (1137 days ago) @ David Turell
About six million years ago in Crete:
https://phys.org/news/2021-10-oldest-footprints-pre-humans-crete.html
"The oldest known footprints of pre-humans were found on the Mediterranean island of Crete and are at least six million years old, says an international team of researchers
***
"The footprints from fossilized beach sediments were found near the west Cretan village of Trachilos and published in 2017. Using geophysical and micropaleontological methods, researchers have now dated them to 6.05 million years before the present day, making them the oldest direct evidence of a human-like foot used for walking. "The tracks are almost 2.5 million years older than the tracks attributed to Australopithecus afarensis (Lucy) from Laetoli in Tanzania," Uwe Kirscher says. This puts the Trachilos footprints at the same age as the fossils of the upright-walking Orrorin tugenensis from Kenya. Finds connected with this biped include femurs, but there are no foot bones or footprints.
"The dating of the Cretan footprints therefore sheds new light on the early evolution of human perambulation more than six million years ago. "The oldest human foot used for upright walking had a ball, with a strong parallel big toe, and successively shorter side toes," says Per Ahlberg, professor at Uppsala University and co-author of the study. "The foot had a shorter sole than Australopithecus. An arch was not yet pronounced and the heel was narrower."
"Six million years ago, Crete was connected to the Greek mainland via the Peloponnese. According to Professor Madelaine Böhme, "We cannot rule out a connection between the producer of the tracks and the possible pre-human Graecopithecus freybergi." Several years ago, Böhme's team identified that previously unknown pre-human species in what is now Europe on the basis of fossils from 7.2 million-year-old deposits in Athens, just 250 kilometers away.
***
"Recent research in paleoanthropology also suggested that the African ape Sahelanthropus could be ruled out as a biped, and that Orrorin tugenensis, which originated in Kenya and lived 6.1 to 5.8 million years ago, is the oldest pre-human in Africa, Böhme says. Short-term desertification and the geographic distribution of early human predecessors could therefore be more closely related than previously thought. On the one hand, a desertification phase 6.25 million years ago in Mesopotamia could have initiated a migration of European mammals, possibly including apes, to Africa. On the other hand, the second-phase sealing off of the continents by the Sahara 6 million years ago could have enabled a separate development of the African pre-human Orrorin tugenensis in parallel with a European pre-human. According to this principle, called "desert swing" by Böhme, successive short-term desertifications in Mesopotamia and the Sahara caused a migration of mammals from Eurasia to Africa."
Comment: Crete is not Africa but it seems early hominins were African, so these footprints pose an origin puzzle. Obviously climate plays a large role.
Human evolution: presents another huge gap
by David Turell , Thursday, November 11, 2021, 05:11 (1106 days ago) @ David Turell
Erectus is a giant step from previous forms:
https://evolutionnews.org/2021/11/missed-opportunity-passing-over-scientific-problems-w...
"At most, the data he cites simply shows that humans, Neanderthals, and Denisovans share certain similar genes and genetic traits which are involved in our brain development and linguistic abilities — genes and genetic traits not found in living apes. This is not at all surprising since Neanderthals and Denisovans were highly similar to us, are thought to have had advanced cognitive abilities, and may even belong within our own species Homo sapiens. The evidence he recounts is not evidence of evolution. Rather, it simply identifies human-specific genetic features that probably help endow us with our advanced cognitive abilities. Merely identifying important genetic traits does not necessarily tell us that they arose by blind evolutionary mechanisms.
***
"First, miracle mutation accounts of the origin of human cognition imply a teleology and design to evolution that contradict an unguided evolutionary story. If our cognitive abilities suddenly evolved by just one or two single mutational events, that implies that our profound human intelligence was sitting on a precipice, just waiting for certain specific mutations to occur before modern human minds could arise. But how did our minds get to that evolutionary precipice, where just one or two mutations could produce everything from Lao Tzu to Beethoven to Einstein? The idea implies a teleological, directed, and designed course to the origin of our cognition.
***
"...arguments that one or a few random mutations magically created humanity’s advanced intellectual abilities strain credulity. The origin of human cognition and speech would have required many changes that represent a suite of complex interdependent traits. Two leading evolutionists writing in a prominent text on primate origins explain that human language could not evolve in an abrupt manner, genetically speaking, because many genetic changes would be necessary:
"Bickerton’s proposal of a single-gene mutation is, I think, too simplistic. Too many factors are involved in language learning — production, perception, comprehension, syntax, usage, symbols, cognition — for language to be the result of a single mutation event.
"Humans are quite different because they possess language, which underlies every major intellectual achievement of humanity. This discontinuity theory is implausible because evolution cannot proceed by inspired jumps, only by accretion of beneficial variants of what went before.
"These authors are correct to reject such “single mutation event” hypotheses — and would be justified in doing the same for two or three mutation events because human cognition is vastly too complex to arise in such a fashion.
Please see part II
Human evolution: presents another huge gap II
by David Turell , Thursday, November 11, 2021, 05:12 (1106 days ago) @ David Turell
"To understand this challenge, let’s consider a seemingly simple example. In 2004 a study in Nature proposed that a single mutation that inactivated a protein could cause “marked size reductions in individual muscle fibres and entire masticatory muscles” leading to “loss of masticatory strength,”8 which could have loosened jaw muscles, allowing our brains to grow larger. A news story widely circulated, titled “Missing link found in gene mutation,” framed the finding this way: “an ancient genetic mutation for weaker jaws helped increase brain size, a twist that first separated the earliest humans from their apelike ancestors.” The story sounds plausible, but there’s more to it. Leading paleoanthropologist Bernard Wood noted that this mutation alone could never have provided a selectable advantage, and would have required additional changes:
"The mutation would have reduced the Darwinian fitness of those individuals. … It only would’ve become fixed if it coincided with mutations that reduced tooth size, jaw size and increased brain size. What are the chances of that?
"We thus have a situation where multiple coordinated mutations would be necessary to provide the advantage. Yet a 2008 population genetics study in Genetics found that to obtain only two specific mutations via Darwinian evolution, “for humans with a much smaller effective population size, this type of change would take > 100 million years.” The authors admitted this was “very unlikely to occur on a reasonable timescale.” In other words, when a trait requires multiple mutations before an advantage is gained, it would require more than 100 million years within a species such as ours.
***
"...he misses another major opportunity to point out a serious deficiency in the evidence for human evolution: the lack of fossil evidence documenting a transition from the ape-like australopithecines to the human-like Homo. This “gap” in the fossil record is well attested in the literature.
"One Nature paper noted that early Homo erectus shows “such a radical departure from previous forms of Homo (such as H. habilis) in its height, reduced sexual dimorphism, long limbs and modern body proportions that it is hard at present to identify its immediate ancestry in east Africa”11 — or anywhere else for that matter. Another review similarly notes, “…it is this seemingly abrupt appearance of H. erectus that has led to suggestions of a possible origin outside Africa.”12 Likewise, a paper in the Journal of Molecular Biology and Evolution found that Homo and Australopithecus differ significantly in brain size, dental function, increased cranial buttressing, expanded body height, visual, and respiratory changes, stating:
"We, like many others, interpret the anatomical evidence to show that early H. sapiens was significantly and dramatically different from… australopithecines in virtually every element of its skeleton and every remnant of its behavior."
Comment: Please see part I. This comes from a critical review of "In Quest of the Historical Adam", by William Lane Craig, recently published.
Human evolution: Denisovan bones and now artifacts
by David Turell , Tuesday, November 30, 2021, 15:32 (1087 days ago) @ David Turell
Deeper digging at 200,000 years ago in the cave:
https://www.livescience.com/oldest-denisovan-fossils-in-siberian-cave
"Scientists have unearthed the oldest fossils to date of the mysterious human lineage known as the Denisovans. With these 200,000-year-old bones, researchers have also for the first time discovered stone artifacts linked to these extinct relatives of modern humans, a new study find
***
"'This is the first time we can be sure that Denisovans were the makers of the archaeological remains we found associated with their bone fragments," Douka said.
"The new findings suggest these newfound Denisovans lived during a time when, according to previous research, the climate was warm and comparable to today, in a locale favorable to human life that included broad-leaved forests and open steppe. Butchered and burnt animal remains found in the cave suggest the Denisovans may have fed on deer, gazelles, horses, bison and woolly rhinoceroses.
"'We can infer that Denisovans were well-adapted to their environments, utilizing every resource available to them," Douka said.
"The stone artifacts found in the same layer as these Denisovan fossils are mostly scraping tools, which were perhaps used for dealing with animal skins. The raw material for these items likely came from river sediment just outside the entrance to the cave, and the river likely helped the Denisovans when they sought to hunt, the scientists noted.
***
"The stone tools linked with these new fossils have no direct counterparts in north or central Asia. However, they do bear some resemblance to items found in Israel dating between 250,000 and 400,000 years ago — a period linked with major shifts in human technology, such as the routine use of fire, the researchers noted.
"The new study found that Denisovans may not have been the only occupants of the cave at this time. Bones of carnivores such as wolves and wild dogs suggest Denisovans may have actively competed with these predators over prey and perhaps the cave itself."
Comment: each group of early humans followed the same path of development of lifestyles as God's endpoint of evolution.
Human evolution: bushier than ever
by David Turell , Saturday, December 04, 2021, 02:24 (1083 days ago) @ David Turell
One new opinion:
https://www.realclearscience.com/2021/12/03/there_are_a_lot_more_human_species_out_ther...
"Everything that’s been called Homo sapiens, isn’t.
In my opinion, far too many species have been lumped together into this one taxonomic category. The truth of the human story is far more complicated, with more species and even more genera than have been named, and more dead ends on the branches of the human family tree than have been recognized.
***
"I’ve continued to document the human fossil record with detailed descriptions and lots of photographs. And the more specimens I study, the more I realize that most of the species designations don’t make sense. If hominin fossils were treated the same way as nonhuman primates, specimens currently lumped into the same group would be allocated to different ones. We need to go back to taxonomic basics.
"Having studied so many human fossils is both a blessing and a curse. The “blessing” is that I can apply my theoretical and comparative background to virtually the entire human fossil record. The “curse”: I don’t always see eye to eye with other paleoanthropologists, who often focus on one or two “species,” a geographic area, or a period of time.
"We humans are the only surviving species of our immediate evolutionary group. This often leads people, including researchers, to make an intuitive but not necessarily correct assumption: The closer one gets to the present, the fewer contemporary species there should be.
***
"From my decadeslong study of recent human skulls from all continents, I’d say H. sapiens has a few key physical features. There is no continuous brow above the orbital sockets and across the nasal region. Our lower face is vertical and a lot narrower across than our cheekbones; you can feel this yourself. Most importantly, we’re the only living mammal with a true chin: not just a bulge but an upside-down T shape that often becomes triangular as a person grows older.
***
"All European Upper Paleolithic humans, on the other hand, such as from Cro-Magnon, do have all of these features, so they’re H. sapiens. I would say the oldest collected specimen of H. sapiens is from Border Cave, South Africa, which is perhaps as old as 174,000 years.
"In my view, the pot currently labeled H. sapiens contains specimens representing at least a few species, and these species are our closest extinct relatives. Even closer than Neanderthals and the recently described “Dragon Man,” proposed as Homo longi, from China.
"Many people think that DNA accurately reveals the picture of human evolution. But this isn’t true.
"First of all, DNA has only been successfully extracted from a handful of fossils, including some Neanderthals, some Upper Paleolithic and near-recent humans, a partial finger bone from Denisova Cave, and two bones from Sima de los Huesos, Spain. Since DNA usually degrades within 100,000 years, we’ll only ever have DNA from a minuscule fraction of fossils; DNA analyses are missing most of the pieces of the puzzle. And there are circular arguments: DNA is identified as, say, Neanderthal because the fossil was identified as such, and then it is used to identify other fossils as Neanderthal, even if they don’t look Neanderthal-like.
"While certain similarities between our DNA and Neanderthal DNA have been interpreted as evidence of the two species interbreeding, these similarities could just be run-of-the-mill features of the genome, common to many species.
"In the crush to embrace interbreeding as the source of human-Neanderthal molecular similarity, people sometimes forget to ask the question: If humans and Neanderthals actually crossed paths as often as molecular anthropologists claim—which is not supported by archaeological or paleontological evidence—would they have recognized each other as potential mates? I don’t think so: They looked too different. Even present-day hunter-gatherer groups have been observed to engage in violence when they encounter each other. And there is evidence from the 49,000-year-old site El Sidrón, that Neanderthals cannabilized other Neanderthals.
***
"To me, however, all of human evolution, even well after our own species first emerged, is a mess of branches and dead ends. Our evolutionary history is complicated, and we should embrace that."
Comment: Argumentative voices add to our thoughts. I think the dhw theory is right on, but I come with a slightly different twist. God didn't want a free-for-all. God is too purposeful for that. Recognizing mistakes will happen in a free-flowing human living system as it is developed. many humanlike types scattered into many environments will naturally adapt many good attributes which will contribute to the final H. sapiens product.
Human evolution: upright posture requires spinal changes
by David Turell , Tuesday, December 07, 2021, 20:04 (1080 days ago) @ David Turell
In the lumbar area:
https://elifesciences.org/articles/70447
"Adaptations of the lower back to bipedalism are frequently discussed but infrequently demonstrated in early fossil hominins. Newly discovered lumbar vertebrae contribute to a near-complete lower back of Malapa Hominin 2 (MH2), offering additional insights into posture and locomotion in Australopithecus sediba. We show that MH2 possessed a lower back consistent with lumbar lordosis and other adaptations to bipedalism, including an increase in the width of intervertebral articular facets from the upper to lower lumbar column (‘pyramidal configuration’). These results contrast with some recent work on lordosis in fossil hominins, where MH2 was argued to demonstrate no appreciable lordosis (‘hypolordosis’) similar to Neandertals. Our three-dimensional geometric morphometric (3D GM) analyses show that MH2’s nearly complete middle lumbar vertebra is human-like in overall shape but its vertebral body is somewhat intermediate in shape between modern humans and great apes. Additionally, it bears long, cranially and ventrally oriented costal (transverse) processes, implying powerful trunk musculature. We interpret this combination of features to indicate that A. sediba used its lower back in both bipedal and arboreal positional behaviors, as previously suggested based on multiple lines of evidence from other parts of the skeleton and reconstructed paleobiology of A. sediba."
Comment: upright posture requires pelvic changes and a development of lumbar lordosis, which apes do not have. Why these changes appeared presents a chicken and egg question. Did continuous attempts at bipedal locomotion produce the change? Not likely with a dependence upon chance mutations. On the other hand if provided with the proper spinal anatomy upright, posture becomes easy to manage. Design is obvious.
Human evolution: the homo bush interbred lots
by David Turell , Monday, December 13, 2021, 15:18 (1074 days ago) @ David Turell
Latest studies:
https://www.sciencenews.org/article/human-evolution-mating-2021-research
"Evidence that cross-continental Stone Age networking events powered human evolution ramped up in 2021.
"A long-standing argument that Homo sapiens originated in East Africa before moving elsewhere and replacing Eurasian Homo species such as Neandertals has come under increasing fire over the last decade. Research this year supported an alternative scenario in which H. sapiens evolved across vast geographic expanses, first within Africa and later outside it.
"The process would have worked as follows: Many Homo groups lived during a period known as the Middle Pleistocene, about 789,000 to 130,000 years ago, and were too closely related to have been distinct species. These groups would have occasionally mated with each other while traveling through Africa, Asia and Europe. A variety of skeletal variations on a human theme emerged among far-flung communities. Human anatomy and DNA today include remnants of that complex networking legacy, proponents of this scenario say.
"It’s not clear precisely how often or when during this period groups may have mixed and mingled. But in this framework, no clear genetic or physical dividing line separated Middle Pleistocene folks usually classed as H. sapiens from Neandertals, Denisovans and other ancient Homo populations.
“'Middle Pleistocene Homo groups were humans,” says paleoanthropologist John Hawks of the University of Wisconsin–Madison. “Today’s humans are a remix of those ancient ancestors.”
"New fossil evidence in line with that idea came from Israel. Braincase pieces and a lower jaw containing a molar tooth unearthed at a site called Nesher Ramla date to between about 140,000 and 120,000 years ago. These finds’ features suggest that a previously unknown Eurasian Homo population lived at the site (SN Online: 6/24/21), a team led by paleoanthropologist Israel Hershkovitz of Tel Aviv University reported. The fossils were found with stone tools that look like those fashioned around the same time by Middle Easterners typically classified as H. sapiens, suggesting that the two groups culturally mingled and possibly mated.
"Interactions like these may have facilitated enough mating among mobile Homo populations to prevent Nesher Ramla inhabitants and other Eurasian groups from evolving into separate species, Hershkovitz proposed.
***
"Dragon Man — like Nesher Ramla Homo — may hail from one of many closely related Homo lines that occasionally mated with each other as some groups moved through Asia, Africa and Europe. From this perspective, Middle Pleistocene Homo groups evolved unique traits during periods of isolation and shared features as a result of crossing paths and mating. (my bold)
Comment: the bold supports my theory about the importance of a homo bush providing an excellent combination of necessary traits for the final human form as God guided evolution to the current endpoint.
Human evolution: oxidative protection
by David Turell , Wednesday, January 05, 2022, 21:24 (1051 days ago) @ David Turell
Ours is better than all others:
https://phys.org/news/2022-01-modern-humans-effective-oxidative-stress.html
"Very few proteins in the body have adaptations that make them unique compared to the corresponding proteins in Neanderthals and apes. Researchers at the Max Planck Institute for Evolutionary Anthropology in Germany and Karolinska Institutet in Sweden have now studied one such protein, glutathione reductase, which protects against oxidative stress. They show that the risk for inflammatory bowel disease and vascular disease is increased several times in people carrying the Neanderthal variant.
"What makes modern humans unique is a question that has eluded researchers for a long time. One way to approach this question is to study the proteins, or building blocks, in the body that have changes that are carried by almost all living people today and occurred after we separated from the ancestors we shared with Neanderthals about 500,000 years ago. There are around 100 proteins that have such a unique change. One of these proteins is glutathione reductase, which is part of the body's defense against oxidative stress.
***
"The study also shows that the Neanderthal protein has passed over to present-day humans in low frequency when our ancestors mixed with them about 60,000 years ago. Today, it occurs mainly on the Indian subcontinent at an estimated frequency of 1 to 2 percent of the population. The researchers found that people who carry the Neanderthal protein have a higher risk of developing vascular disease and inflammatory bowel disease, both diseases that are linked to oxidative stress.
"'The risk increases we see are large; several times increased risk of inflammatory bowel disease and vascular disease," says Hugo Zeberg.
The researchers can only speculate about why this particular change came to be one of the unique changes that almost all modern humans carry.
"'Stopping oxidative stress is a bit like preventing something from rusting. Perhaps the fact that we are living longer has driven these changes," says Svante Pääbo."
Comment: another finding which supports the theory that God preferred the arrival of modern humans with special attributes. Good we are not Neanderthals
Human evolution: obesity problems are mental
by David Turell , Thursday, January 06, 2022, 18:37 (1050 days ago) @ David Turell
Evolution set us up to fight starvation so in good times sapiens stored fat which is very high in calories. Now in civilized times plenty of food is around, eating is enjoyable and many of us get fat.
https://www.newscientist.com/article/mg25333682-800-have-we-got-the-science-of-obesity-...
"IN PRINCIPLE, it sounds simple: eat less and move more. This dietary advice for tackling obesity has been around for decades. Yet, despite all the calorie counting, dieting and exercising, worldwide obesity rates just keep ticking up. People in the US, for example, were heavier in 2021 than they were in 2020, placing many more people at risk from diabetes and other serious chronic diseases. So why hasn’t this approach to weight control worked?
"One possibility is that we haven’t tried hard enough. Perhaps we have lacked the discipline and willpower to maintain healthy dietary and exercise habits – a challenge made more difficult today for those surrounded by inexpensive, tasty, highly processed foods.
Or perhaps the problem is the focus on “calorie balance” itself. In a recent paper, my colleagues and I question the basic assumption of whether taking in more calories than you burn really is the primary cause of obesity. We argue that the evidence actually points the other way: we are driven to overeat because we are getting fatter
"This may seem incredible, but consider the adolescent growth spurt. As their growth rate speeds up, teenagers may eat hundreds of calories more each day than they used to. Does this “overeating” cause the rapid growth? Or does the rapid growth, which requires more calories to build new body tissues, make teens hungrier so they eat more? Clearly the latter, as adults won’t grow taller, no matter how much they eat.
"The key to how this works in obesity is hormones, especially the fat-storage hormone insulin. Processed, rapidly digestible carbohydrates – foods like sweetened breakfast cereals, potato chips and sugary beverages – raise our insulin level too high. This causes our fat cells to take in and store too many calories, leaving fewer available for the rest of the body. A few hours after eating a high-carb meal, the number of calories in the bloodstream plummets, so we get hungrier sooner after eating.
"The two opposing views of cause and effect in obesity have radically different implications for how to prevent and treat weight problems. Whereas the usual approach focuses on how much to eat, with prescriptions for daily calorie intake, in our view, the emphasis should be placed on what to eat.
"Replacing processed carbs with high-fat foods – such as nuts, full-fat dairy, olive oil, avocado and dark chocolate – lowers insulin levels, making more calories from the meal available for the rest of the body. Counter-intuitively, higher-fat foods may help shed body fat, a possibility supported by clinical trials comparing high-fat diets with low-fat ones.
"This way of thinking might help explain why calorie restriction usually fails long before a person with obesity approaches an ideal body weight. A low-calorie, low-fat diet further restricts an already limited supply of energy to the body, exacerbating hunger without addressing the underlying predisposition to store too many calories in body fat. Consequently, weight loss becomes a battle between mind and metabolism that most people will probably lose."
Comment: The authors do not mention that very low calorie diets, as in starvation among early homo populations set into motion an evolved automatic reduction in basal metabolism of 300 calories per day. Basal metabolism is the caloric requirement of maintaining the bodily functions. The old Adkins diet worked, because it allowed protein in meats with some accompanying fat. Proteins are difficult for the body to use and the net calories are only 70% left for energy consumption. Complex carbohydrates in complex starches were allowed but not the simple sugars as the article warns. It is a mental challenge because evolution did not set us up for our current lifestyles. The authors are correct. Only 15% of dieters maintain weight loss by mental determination. dhw and I are two of those folks. Weight loss
requires a determined mental vigilance which is not easy. I know.
Human evolution: first big game hunting
by David Turell , Wednesday, January 12, 2022, 00:11 (1044 days ago) @ David Turell
About two million years ago:
https://www.newscientist.com/article/2303888-ancient-humans-may-have-started-hunting-2-...
Ancient humans were regularly butchering animals for meat 2 million years ago. This has long been suspected, but the idea has been bolstered by a systematic study of cut marks on animal bones.
The find cements the view that ancient humans had become active hunters by this time, contrasting with earlier hominins that ate mostly plants.
The new evidence comes from Kanjera South, an archaeological site near Lake Victoria in Kenya. Kanjera South has been excavated on and off since 1995.
Cut marks on animal bones suggest ancient hominins butchered them for their meat, and that they were first on the scene instead of having to scavenge from carnivores like big cats
Comment: The humans were probably Habilis or Erectus. The rest of the article is behind a paywall.
Human evolution: our special genes
by David Turell , Tuesday, March 08, 2022, 23:29 (989 days ago) @ David Turell
A group just discovered on chromosome 21:
https://phys.org/news/2022-03-genes-unique-humans-source-evolutionary.html
"The team utilized genome alignment tools to compare the most recent drafts of human and chimpanzee genomes, meticulously scanning for novel genetic elements unique to humans. Beginning with the smallest human chromosome, chromosome 21, the researchers were surprised to find a large region of human-unique DNA, called 21p11, that harbors several orphan microRNA genes.
"Although the team found that the long arm of human chromosome 21 aligns well with that of other extant ape species, the short arm aligned poorly, suggesting that this region of the human genome has recently and substantially diverged from that of other primates.
"According to their analysis of prehistoric human genomes, these changes predate the divergence of Neanderthals and modern humans. The genes also show little to no sequence-based variation within the modern human population. The team therefore theorized that the microRNA (miRNA) genes found in that region [miR3648 and miR6724] likely evolved in the time since the chimpanzee and human lineages split, sometime in the last seven million years, and are specific to humans. (my bold)
"Using computational tools, the team discovered with a high degree of likelihood that the predicted gene targets of the relevant miRNAs are related to embryonic development. Both miR3648 and miR6724 have been detected in tissues throughout the human body, including the brain, and may conceivably play a role in the evolution of humankind's most unique organ. The findings point to the intriguing idea that these microRNA genes contributed to the distinct evolution of our species and the uniqueness of humankind.
"'Understanding the genetic basis for human uniqueness is an important undertaking because, despite sharing nearly 99% of our DNA sequences with the chimpanzee, we're remarkably different organisms," said student researcher José Galván. "Small post-transcriptional regulatory elements like miRNAs and siRNAs [small interfering RNA] are under-appreciated and often misunderstood in the effort to understand our genetic differences."
"Thanks to their small size and structural simplicity, miRNA genes have fewer barriers to de novo creation than other gene types. MicroRNA genes can be extremely prolific in their regulation of other genes, meaning that modest changes to DNA sequence can result in wide-ranging impacts to the human genome. The creation of miR3648 and miR6724 serve as excellent examples of this process. This study revealed a new possible mechanism for the creation of new miRNA genes through duplications of rRNA genes, which calls for further research on how general this phenomenon may be."
Comment: note the bold. These genes are seven million years old, fully illustrating design for the future in anticipation of need is exactly how God manages His control of evolution.
Human evolution: special cancer gene
by David Turell , Tuesday, May 03, 2022, 23:21 (933 days ago) @ David Turell
Our genes control cancer less than our primate ancestors:
https://www.newscientist.com/article/2318407-a-single-genetic-mutation-made-humans-more...
"Cancer is relatively rare in other primates. For example, autopsies of 971 non-human primates that died at Philadelphia Zoo in Pennsylvania between 1901 and 1932 found that only eight had tumours.
"Read more: https://www.newscientist.com/article/2318407-a-single-genetic-mutation-made-humans-more...
"To learn why we are more susceptible to cancer, Christine Iacobuzio-Donahue at Memorial Sloan Kettering Cancer Center in New York and her colleagues compared hundreds of genes between humans and 12 non-human primate species.
"They discovered that we have evolved a slightly different version of a gene called BRCA2 since we split from chimpanzees.
"BRCA2 is known as a tumour suppressor gene because it is involved in DNA repair. However, the researchers found that a single DNA letter change in the human BRCA2 gene has made it 20 per cent worse at repairing DNA compared with other primate versions of the gene, which could explain our higher cancer rates.
***
"At this stage, we don’t know why BRCA2 has evolved to become less active in humans than in other primates, says Iacobuzio-Donahue. One possibility is that reduced BRCA2 activity has been selected for in humans to enhance fertility, since research shows that women with BRCA2 variants linked to cancer seem to become pregnant more easily, she says.
"If so, this fertility boost may have come at the cost of higher cancer rates, she adds."
Comment: the advantage must be fertility. We generally make one baby at a time, and going back to primitive times, mothers nursed for over two years which generally blocked ovulation. This means we needed to have a high fertility rate to overcome these factors slowing reproductive rates. As a result, our cancer rate is 20%, while primates are at one percent. Back to theodicy concerns, did God disregard the trade-off consequences? I assume god thought the reproductive rates most important.
Human evolution: among primtes we sleep less
by David Turell , Saturday, May 07, 2022, 00:44 (929 days ago) @ David Turell
Why the cause guesswork:
https://www.smithsonianmag.com/science-nature/why-humans-sleep-less-than-their-primate-...
"Research has shown that people in non-industrial societies — the closest thing to the kind of setting our species evolved in — average less than seven hours a night, says evolutionary anthropologist David Samson at the University of Toronto Mississauga. That’s a surprising number when you consider our closest animal relatives. Humans sleep less than any ape, monkey or lemur that scientists have studied. Chimps sleep around 9.5 hours out of every 24. Cotton-top tamarins sleep around 13. Three-striped night monkeys are technically nocturnal, though really, they’re hardly ever awake — they sleep for 17 hours a day.
"Samson calls this discrepancy the human sleep paradox. “How is this possible, that we’re sleeping the least out of any primate?” he says. Sleep is known to be important for our memory, immune function and other aspects of health. A predictive model of primate sleep based on factors such as body mass, brain size and diet concluded that humans ought to sleep about 9.5 hours out of every 24, not seven. “Something weird is going on,” Samson says.
"Research by Samson and others in primates and non-industrial human populations has revealed the various ways that human sleep is unusual. We spend fewer hours asleep than our nearest relatives, and more of our night in the phase of sleep known as rapid eye movement, or REM. The reasons for our strange sleep habits are still up for debate but can likely be found in the story of how we became human.
***
"Gandhi Yetish, a human evolutionary ecologist and anthropologist at the University of California, Los Angeles, has also spent time with the Hadza, as well as the Tsimane in Bolivia and the San in Namibia. In a 2015 paper, he assessed sleep across all three groups and found that they averaged between only 5.7 and 7.1 hours.
"Humans, then, seem to have evolved to need less sleep than our primate relatives. Samson showed in a 2018 analysis that we did this by lopping off non-REM time. REM is the sleep phase most associated with vivid dreaming. That means, assuming other primates dream similarly, we may spend a larger proportion of our night dreaming than they do. We’re also flexible about when we get those hours of shut-eye.
"To tie together the story of how human sleep evolved, Samson laid out what he calls his social sleep hypothesis in the 2021 Annual Review of Anthropology. He thinks the evolution of human sleep is a story about safety — specifically, safety in numbers. Brief, flexibly timed REM-dense sleep likely evolved because of the threat of predation when humans began sleeping on the ground, Samson says. And he thinks another key to sleeping safely on land was snoozing in a group.
***
"A better understanding of how human sleep evolved could help people rest better, Samson says, or help them feel better about the rest they already get.
“'A lot of people in the global North and the West like to problematize their sleep,” he says. But maybe insomnia, for example, is really hypervigilance — an evolutionary superpower. “Likely that was really adaptive when our ancestors were sleeping in the savannah.”
"Yetish says that studying sleep in small-scale societies has “completely” changed his own perspective.
“'There’s a lot of conscious effort and attention put on sleep in the West that is not the same in these environments,” he says. “People are not trying to sleep a certain amount. They just sleep.'”
Comment: I skipped through a lot of guesswork. No one knows why we sleep in shorter times. What is wrong with considering our very advanced different brain just works that way.?
Human evolution: South African earliest:
by David Turell , Tuesday, July 05, 2022, 19:48 (870 days ago) @ David Turell
Latest study:
https://www.livescience.com/south-african-fossils-human-evolution
"Ancient human-like fossils in South Africa may be more than a million years older than previously thought, which raises the odds that the species they came from gave rise to humans, a new study finds.
"The new date could rewrite a few key stages in the history of human evolution. That's because the finding suggests these fossils belong to a species that may predate the iconic 3.2-million-year-old "Lucy" fossil. Lucy's species was long thought to potentially have been the prime contender for the direct ancestor of humans.
"Homo sapiens is the only surviving member of the human lineage, the genus Homo. Previous research suggested that the leading candidate for the precursors of Homo may be the genus Australopithecus, which lived about 4.1 million to 2.9 million years ago.
***
"The most abundant sources of Australopithecus fossils discovered to date are the Sterkfontein Caves in South Africa, which are part of a site named the Cradle of Humankind. Sterkfontein became famous when the first known adult Australopithecus was discovered there, in 1936. Over the decades, scientists have found hundreds of hominin fossils at Sterkfontein, which are usually classified as members of the species Australopithecus africanus.
***
"In the new study, Granger and his colleagues sought new estimates of the ages of the other hominin fossils at Sterkfontein. They found that those bones may actually be about 3.4 million to 3.7 million years old. This makes them older than Lucy and opens the possibility that Homo could have evolved from the Australopithecus species of South Africa, and not East Africa as long thought.
"Understanding the dates of the fossils at Sterkfontein can be tricky. Normally, scientists estimate the ages of fossils by analyzing the layers in which they are found; the deeper a layer is, the older it may be. However, the complex system of caves at Sterkfontein could lead older deposits to get mixed with younger material, complicating attempts to date them.
***
"One potentially more accurate method involves dating the actual rocks in which the fossils were found. In the new study, researchers analyzed the concrete-like matrix in which the fossils are embedded, called breccia.
"The scientists analyzed so-called cosmogenic nuclides within the rocks. These are extremely rare versions of elements, or isotopes, produced by cosmic rays — high-energy particles that constantly bombard Earth from outer space. Each isotope of an element has a different number of neutrons in its atomic nucleus — for example, aluminum-26 has one less neutron within its nucleus than regular aluminum.
***
"These new findings, which show A. africanus is at least as old as, if not older than, A. afarensis, may rule out the idea that A. africanus descended from A. afarensis. And in fact, A. africanus possesses a more primitive ape-like skull and facial features than A. afarensis, paleoanthropologist Yohannes Haile-Selassie, director of Arizona State University's Institute of Human Origins, who did not take part in this research, told Live Science. Instead, he suggested A. africanus and A. afarensis may be sister species, descended from an older common ancestor such as 3.8-million-year-old A. anamensis, which Haile-Selassie helped unearth in Ethiopia in 2016.
"Another implication of the new work is that "this older age allows more time for the South African species to evolve into later hominins," Granger said. This could include Homo. "We don't know that this happened for sure, but it opens a window of possibility."
"John Hawks, a paleoanthropologist at the University of Wisconsin-Madison who did not participate in this study, noted the new cosmogenic technique will likely not end the controversy of the Sterkfontein fossils' ages.
"'This is a case where the different teams really need to get together and agree on what the geology of the site is telling us," Hawks told Live Science. "I think this paper is a first step in that process, but it will take a lot of work to get these different scientists to agree on what they are seeing.'"
Comment: not a new proof of origin of Homos, but we still are left with a 4.5-million-year evolution of big-brained hominin/Homo forms. As I view God as the designer of evolutionary processes, we can see God prefers evolution as his main process. The universe evolved, the Earth evolved, life evolved after God started each event and pursued it.
Human evolution: African climate and evolution
by David Turell , Tuesday, September 27, 2022, 01:53 (786 days ago) @ David Turell
Deep cores are studied to relate climate to changing ancint types of human ancestors:
https://www.sciencedaily.com/releases/2022/09/220926114929.htm
"Specifically, the scientists found that various anatomically diverse hominin groups inhabited the area during a phase of long-lasting and relatively stable humid conditions from approximately 620,000 to 275,000 years BP (Before Present). However, a series of shorter abrupt and extreme arid pulses interrupted this long generally stable and wet phase. Most likely, this resulted in a fragmentation of habitats, shifts in population dynamics and even the extinctions of local populations. As a result, small, reproductively and culturally isolated populations then had to adapt to dramatically transformed local environments, likely stimulating the appearance of the many geographically and anatomically distinct hominin groups and the separation of our modern human ancestors from archaic groups.
"A phase with significant climate swings resulting in regularly transformed habitats in the area from approximately 275,000 to 60,000 years BP repeatedly resulted in environmental shifts from lush vegetation with deep fresh water lakes to highly arid landscapes with the extensive lakes reduced to small saline puddles. In this phase, the population groups gradually transitioned from Acheulean technologies (oval hand axes made of stone and primarily associated with Homo ergaster/erectus) to more sophisticated Middle Stone Age technologies. This crucial phase also encompasses the emergence of Homo sapiens in eastern Africa as well as key human social, technological, and cultural innovations that could have buffered early Homo sapiens from the impacts of severe environmental changes. 'These innovations, such as more varied toolkits and long-distance transport, would have equipped modern humans with an unprecedented adaptability to the repeated expansions and contractions of habitats,' said Dr Foerster, the paper's lead author.
"The phase from approximately 60,000 to 10,000 years BP saw the most extreme environmental fluctuations, but also the most arid phase of the entire record, which could have acted as a motor for continuous indigenous cultural change. The scientists believe that the brief alignment of humid pulses in eastern Africa with wet phases in north-eastern Africa and the Mediterranean was key to opening favourable migration routes out of Africa on a roughly north-south axis along the East African Rift System (EARS) and into the Levant, facilitating the global dispersal of Homo sapiens.
''In view of current threats to the human habitat from climate change and the overuse of natural resources through human activity, understanding how the relationship between climate and human evolution has become more relevant than ever,' Foerster concluded.
"This research is part of the Hominin Sites and Paleolakes Drilling Project (HSPDP). In order to evaluate the impact that different timescales and magnitudes of climatic shifts have had on the living conditions of early humans, the project has cored five lake archives of climate change during the last 3.5 million years. All five sites in Kenya and Ethiopia are located in close vicinity to paleoanthropological key sites covering various steps in human evolution, with the site in southern Ethiopia exploring the youngest chapter."
Comment: this shows how climate affects evolution very clearly. But there is no relationship to speciation noted in any way.
Human evolution: differing fetal growth from apes
by David Turell , Tuesday, October 04, 2022, 17:22 (779 days ago) @ David Turell
Interesting new approach to our evolution:
https://www.newscientist.com/article/2340725-our-ancestors-prenatal-growth-sped-up-afte...
"Early humans evolved a faster fetal growth rate than other apes about a million years ago, suggesting it could have played a role in the evolution of our species
"High prenatal growth rates found in modern people may have first evolved in ancient hominids less than a million years ago, according to estimates based on fossil teeth.
"Human fetuses grow by around 11.6 grams per day on average – considerably faster than the fetuses of gorillas, the next fastest ape in the hominid family, with a rate of 8.2 grams per day.
“'We found that human-like gestation [may have] preceded the evolution of the [modern human] species – around 200,000 to 300,000 years ago – and may in fact be a critical factor that led to our evolution, particularly our large brains,” says Tesla Monson at Western Washington University.
***
"Monson and her colleagues found that across primates, prenatal growth rates are closely correlated with the ratio of the lengths of the first and third molar teeth.
"The researchers built a mathematical model that could predict prenatal growth rates from the size of molars from 608 primates, including apes and African and Asian monkeys.
"They then used the model to predict the prenatal growth rates of 13 hominid species from their fossil molar teeth. This revealed that hominid prenatal growth rates increased after our lineage split from chimpanzees around 5 to 6 million years ago, becoming more similar to those of modern humans than other apes around 1 million years ago.
"Monson is unsure why prenatal growth rate and the molar length ratio may be related, but she and her team are investigating whether certain genes might control both. She acknowledges that extrapolating prenatal growth from skeletal remains may not be reliable. “Since we don’t have a time machine, we can’t directly compare our reconstructions with real values in the past,” she says.
"However, the estimated rise in prenatal growth rates over this period coincides with increases in pelvis size and brain size among hominids. “It’s really cool that our reconstructions align with so many other lines of evidence,” says Monson.
“'The authors’ primary finding that human-like prenatal growth rates emerged less than 1 million years ago, in concert with major increases in brain size, is convincing,” says Anna Warrener at the University of Colorado Denver.
“"Teeth are frequently found in the fossil record and would be a fantastic tool for such evaluations in the future,” she says.
“'The study is of great importance. It is incredibly difficult to access information about fetal growth rates from skeletal remains due to poor preservation. The authors have opened up new ways of overcoming this obstacle,” says Patrick Mahoney at the University of Kent, UK."
Comment: since we know we evolved this study tells us more of the 'how' but not the 'why'.
Human evolution: as apex predators
by David Turell , Monday, October 17, 2022, 17:18 (766 days ago) @ David Turell
Latest theory:
https://www.sciencealert.com/ancient-humans-were-apex-predators-for-2-million-years-stu...
"Paleolithic cuisine was anything but lean and green, according to a study on the diets of our Pleistocene ancestors.
"For a good 2 million years, Homo sapiens and their ancestors ditched the salad and dined heavily on meat, putting them at the top of the food chain.
It's not quite the balanced diet of berries, grains, and steak we might picture when we think of 'paleo' food.
"But according to a study last year by anthropologists from Israel's Tel Aviv University and the University of Minho in Portugal, modern hunter-gatherers have given us the wrong impression of what we once ate.
"'This comparison is futile, however, because 2 million years ago hunter-gatherer societies could hunt and consume elephants and other large animals – while today's hunter gatherers do not have access to such bounty," researcher Miki Ben‐Dor from Israel's Tel Aviv University explained in 2021.
"A look through hundreds of previous studies – on everything from modern human anatomy and physiology to measures of the isotopes inside ancient human bones and teeth – suggests we were primarily apex predators until roughly 12,000 years ago.
***
"We can find ample evidence of game hunting in the fossil record, but to determine what we gathered, anthropologists have traditionally turned to modern-day ethnography based on the assumption that little has changed.
"According to Ben-Dor and his colleagues, this is a huge mistake.
"'The entire ecosystem has changed, and conditions cannot be compared," said Ben‐Dor.
"The Pleistocene epoch was a defining time in Earth's history for us humans. By the end of it, we were marching our way into the far corners of the globe, outliving every other hominid on our branch of the family tree.
***
"'We decided to use other methods to reconstruct the diet of stone-age humans: to examine the memory preserved in our own bodies, our metabolism, genetics and physical build," said Ben‐Dor.
"'Human behavior changes rapidly, but evolution is slow. The body remembers."
For example, compared with other primates, our bodies need more energy per unit of body mass. Especially when it comes to our energy-hungry brains. Our social time, such as when it comes to raising children, also limits the amount of time we can spend looking for food.
"We have higher fat reserves, and can make use of them by rapidly turning fats into ketones when the need arises. Unlike other omnivores, where fat cells are few but large, ours are small and numerous, echoing those of a predator.
"Our digestive systems are also suspiciously like that of animals higher up the food chain. Having unusually strong stomach acid is just the thing we might need for breaking down proteins and killing harmful bacteria you'd expect to find on a week-old mammoth chop.
Even our genomes point to a heavier reliance on a meat-rich diet than a sugar-rich one.
"'For example, geneticists have concluded that areas of the human genome were closed off to enable a fat-rich diet, while in chimpanzees, areas of the genome were opened to enable a sugar-rich diet," said Ben‐Dor.
"The team's argument is extensive, touching upon evidence in tool use, signs of trace elements and nitrogen isotopes in Paleolithic remains, and dental wear.
"It all tells a story where our genus' trophic level – Homo's position in the food web – became highly carnivorous for us and our cousins, Homo erectus, roughly 2.5 million years ago, and remained that way until the upper Paleolithic around 11,700 years ago."
Comment: not the usual view, but it recognizes that we have a new food supply in farming which is only 11,000 years old.
Human evolution: current and expected population
by David Turell , Thursday, October 20, 2022, 19:13 (763 days ago) @ David Turell
Groth is slowing:
https://bigthink.com/strange-maps/8-billion-people/?utm_source=mailchimp&utm_medium...
:At or around November 15th, humanity will add its eight billionth member. That sounds alarming, but fertility rates have been dropping since the 1960s. China and India, both 1.4 billion now, could shrink to 500 million and 1 billion, respectively. From the perspective of planetary biomass, humans make up a tiny 0.01%.
"Humanity is hardly an exclusive club. No secret handshake required. On November 15th, the United Nations predicts that we’ll be adding our eight billionth (living) member.
"This is an alarming milestone to some, not just because of the number’s sheer magnitude — imagine London’s 90,000-seater Wembley Stadium, squared — but also due to the breakneck speed at which we’ve reached it. After all, it took us all of human history up to 1804 to reach our first billion. And then we needed just 123 years to get to the second one.
"That was in 1927. Less than a century on, that figure has now quadrupled. But population growth is no runaway train. The global fertility rate has been dropping since 1964, down from 5 births per woman to just under 2.5 today.
"As a result, the speed of population growth has already plateaued. Since 1960 — when we achieved our third billion — we’ve added billions at a stable interval, of about one every 12 to 14 years. The UN Population Division projects that those intervals will get longer again after billion number eight, and humanity will hit its peak — numerically speaking at least — by the end of the century, at just under 11 billion.
"The ensuing population crunch will of course cause a bunch of worries and problems of its own. Yet knowing that the curve will eventually tilt downward is a welcome bit of good news. It marks a refreshing change from other, more intractable threats to our continued existence, like climate change, nuclear proliferation, and resource depletion.
"All of this serves as a long-winded introduction to a remarkable realization: Instead of preludes to disaster, maps like these may become objects of future curiosity. A century or two from now, our successors, inhabiting a less crowded planet, may study them and marvel, “Look how many we once were!”
Comment: the remainder of the article covers pie maps of where we all are by geographic areas. Eleven billion and then decline is an interesting concept. All depends on birth rate couples decide upon. The is the 'humans plus food' dhw rales about.
Human evolution: cannibalism
by David Turell , Wednesday, October 26, 2022, 00:35 (758 days ago) @ David Turell
It was used by humans:
https://www.realclearscience.com/blog/2022/10/26/why_did_paleolithic_humans_eat_each_ot...
"Our Paleolithic ancestors ate each other. We (Homo sapiens) did it. Neanderthals did it. Homo erectus and Homo antecessor did it. It's highly likely that almost all hominins have done it. The only questions are "why" and "how much".
"From our privileged position today as the apex species on planet Earth, with a relative bounty of plant and animal food compared to times past, cannibalism is almost universally abhorred. But did this aversion exist amongst our ancestors? Scientists generally view Paleolithic cannibalism as the exception, not the norm, but maybe that's just wishful thinking... Picturing our ancients as noble hunters and gatherers is preferable to viewing them as brutish, opportunistic cannibals.
***
"Cole described a few clear signs on human bones that suggest cannibalism:
"'lack of a cranial base (to get to the brain) on otherwise complete or near-complete skeletons;"
"'virtual absence of vertebrae (due to crushing or boiling to get at bone marrow and grease);"
"'cut- and chop-marks;"
"'comparable butchering techniques on human remains as in faunal (food) remains;"
"'post-processing discard of hominin remains similar to faunal remains;"
"'evidence of cooking in the form of burnt bone;"
"'human tooth marks"
"These indicators have been spotted at ancient human sites around the world, from 10,000 to nearly one million years before present. At Troisième caverne of Goyet in Belgium, researchers found evidence that around 45,000 years ago, Neanderthals butchered then ate some of their dead and used their bones as tools. And in Gough’s Cave in the United Kingdom, dated to roughly 15,000 years ago, anthropologists discovered bite marks on Homo sapien bones, as if the long-ago eaters were trying to scrape off every millimeter of nutritious muscle. They also turned up hundreds of filleting marks and ritualistic incisions on bones, and even found skulls apparently modified for use as cups.
"So did humans eat each other opportunistically, perhaps upon the death of a group member? Was it more out of necessity, in situations of starvation? Or did humans in rival groups hunt each other like they might a deer or a boar? Cole tried to answer that question by calculating the number of calories in an adult man. He found it to be about 143,771, enough to feed a group of about 25 adult humans for half a day. (my bold)
" He reasoned that this nutritional prize wouldn't really be worth the trouble, especially compared to hunting a horse, an aurochs, or mammoth, ruling out the notion that ancient humans regularly hunted each other.
"'A single large fauna individual returns many more calories without the difficulties of hunting groups of hominins that were as intelligent and resourceful as the hunters."
"As Cole wrote, that means Paleolithic cannibalism was more likely carried out opportunistically, by necessity, or perhaps for ritualistic purposes. Ancient culture undoubtedly factored in, but on that topic, we may forever be kept in the dark."
Comment: note my bold. Humam caloric need on a daily basis is a vital concept. dhw belittles it in his arguments about God's necessary roles. Note how the author makes it a critical point in studying human behavior in reference to food supply.
Human evolution: no hominin ancestor
by David Turell , Thursday, October 27, 2022, 17:20 (756 days ago) @ David Turell
Current fossils refuted:
https://evolutionnews.org/2022/10/the-standard-story-of-human-evolution-a-critical-look/
"[T]he evolutionary sequence for the majority of hominin lineages is unknown. Most hominin taxa, particularly early hominins, have no obvious ancestors, and in most cases ancestor-descendant sequences (fossil time series) cannot be reliably constructed.
***
"Although Sahelanthropus tchadensis (also known as the Toumai skull) is known only from one skull and some jaw fragments, it has been called the oldest-known hominin on the human line. When first published, articles in the journal Nature called it “the earliest known hominid ancestor” and “close to the last common ancestor of humans and chimpanzees”; as of 2020, the Smithsonian Institution still called it “one of the oldest known species in the human family tree.”
***
"In 2020, nearly two decades after the fossil was first reported, the debate was seemingly settled when the femur of Sahelanthropus was finally described, confirming that it was a quadruped with a chimp-like body plan. This evidence forced the researchers to suggest that if Sahelanthropus were a human ancestor, then that would mean bipedality is no longer a necessary qualification for status as a hominid — an unorthodox view that would wreak havoc with the primate tree. More likely is the view of Madelaine Böhme at the University of Tübingen in Germany: “itʼs more similar to a chimp than to any other hominin,” meaning, as another commentator put it, Sahelanthropus “was not a hominin, and thus was not the earliest known human ancestor.”
***
"Paleoanthropologists initially claimed Orrorin’s femur indicates bipedal locomotion “appropriate for a population standing at the dawn of the human lineage,”15 but a later Yale University Press commentary admitted, “All in all, there is currently precious little evidence bearing on how Orrorin [tugenensis] moved.”
***
"In 2009, Science announced the long-awaited publication of details about Ardipithecus ramidus (pictured above), a would-be hominin fossil that lived about 4.4 million years ago (mya). Expectations mounted after its discoverer, UC Berkeley paleoanthropologist Tim White, promised a “phenomenal individual” that would be the “Rosetta stone for understanding bipedalism.”
***
"As the authors of the Nature article stated, Ardi’s “being a human ancestor is by no means the simplest, or most parsimonious explanation.”29Sarmiento even observed that Ardi had characteristics different from both humans and African apes, such as its unfused jaw joint, which ought to remove her far from human ancestry.30
"Whatever Ardi was, everyone agrees the fossils was initially badly crushed and needed extensive reconstruction. No doubt this debate will continue, but are we obligated to accept the “human ancestor” position promoted by Ardi’s discoverers in the media? Sarmiento doesn’t think so. According Time magazine, he “regards the hype around Ardi to have been overblown.
Comment: there is a major fossil gap for pre-hominin forms. It is not a Cambrian gap. We simply don't have enough fossils found to make believable series. Here I agree with dhw. We need and hope to find more. On the other hand, if Bechly is correct in his view of fossil finding, and what we have is all there is, there would be a Cambrian-like gap.
Human evolution: virus DNA in our immune system
by David Turell , Saturday, October 29, 2022, 17:34 (754 days ago) @ David Turell
Protection from the past:
https://www.sciencedaily.com/releases/2022/10/221027154145.htm
"Viral DNA in human genomes, embedded there from ancient infections, serve as antivirals that protect human cells against certain present-day viruses, according to new research.
***
"Previous studies have shown that fragments of ancient viral DNA -- called endogenous retroviruses -- in the genomes of mice, chickens, cats and sheep provide immunity against modern viruses that originate outside the body by blocking them from entering host cells. Though this study was conducted with human cells in culture in the lab, it shows that the antiviral effect of endogenous retroviruses likely also exists for humans.
"The research is important because further inquiry could uncover a pool of natural antiviral proteins that lead to treatments without autoimmune side effects. The work reveals the possibility of a genome defense system that has not been characterized, but could be quite extensive.
***
"Endogenous retroviruses account for about 8% of the human genome -- at least four times the amount of DNA that make up the genes that code for proteins. Retroviruses introduce their RNA into a host cell, which is converted to DNA and integrated into the host's genome. The cell then follows the genetic instructions and makes more virus.
"In this way, the virus hijacks the cell's transcriptional machinery to replicate itself. Typically, retroviruses infect cells that don't pass from one generation to the next, but some infect germ cells, such as an egg or sperm, which opens the door for retroviral DNA to pass from parent to offspring and eventually become permanent fixtures in the host genome.
"In order for retroviruses to enter a cell, a viral envelope protein binds to a receptor on the cell's surface, much like a key into a lock. The envelope is also known as a spike protein for certain viruses, such as SARS-CoV-2.
***
"The study shows how one human protein of retroviral origin blocks a cell receptor that allows viral entry and infection by a broad range of retroviruses circulating in many non-human species. In this way, Feschotte said, ancient retroviruses integrated into the human genome provide a mechanism for protecting the developing embryo against infection by related viruses.
"Future work will explore the antiviral activity of other envelope-derived proteins encoded in the human genome, he said."
Comment: in the past I proposed that God used viruses to advance evolution. This study supports the point.
Human evolution: Madagascar population study
by David Turell , Friday, November 04, 2022, 15:51 (748 days ago) @ David Turell
Both Asian and African groups studied:
https://phys.org/news/2022-11-human-expansion-years-linked-madagascar.html
"The island of Madagascar—one of the last large land masses colonized by humans—sits about 250 miles (400 kilometers) off the coast of East Africa. While it's still regarded as a place of unique biodiversity, Madagascar long ago lost all its large-bodied vertebrates, including giant lemurs, elephant birds, turtles, and hippopotami. A human genetic study reported in the journal Current Biology on November 4 links these losses in time with the first major expansion of humans on the island, around 1,000 years ago.
"'This human demographic expansion was simultaneous with a cultural and ecological transition on the island," says Denis Pierron, French National Center for Scientific Research (CNRS) researcher in Toulouse, France. "Around the same period, cities appeared in Madagascar and all the vertebrates of more than 10 kilograms disappeared."
"The origins of humans in Madagascar has long been an enigma, Pierron explained. Madagascar is home to 25 million people who speak an Asian language despite the island's proximity to East Africa. Other groups who speak similar languages live more than 4,000 miles away. The people that live on Madagascar are known to trace their roots back to two small populations: one Bantu-speaking from Africa and another Austronesian-speaking from Asia. But, beyond that, the history remained rather murky.
"In the new study, Pierron and his colleagues took a close look at the human genetic evidence. More specifically, they closely studied how various segments of human chromosomes were shared together with local ancestry information and computer-simulated genetic data. Together, they've inferred that the Malagasy ancestral Asian population was isolated on the island for more than 1,000 years with an effective population size of just a few hundred individuals.
"Their isolation ended about 1,000 years ago when a small group of Bantu-speaking African people came to Madagascar. Afterward, the population continued to expand rapidly over generations. The growing human population led to extensive changes to the Madagascar landscape and the loss of all large-bodied vertebrates that once lived there, they suggest.
***
"'Our study supports the theory that it was not directly the arrival of humans on the island that caused the disappearance of the megafauna, but rather a change in lifestyle that caused both a human population expansion and a reduction in biodiversity in Madagascar," Pierron says.
"While these efforts have led to much better understanding of Madagascar's history, many intriguing questions remain. For instance, Pierron asks, "If the ancestral Asian population was isolated for more than a millennium before mixing with the African population, where was this population? Already in Madagascar or in Asia? Why did the Asian population isolate itself over 2,000 years ago? Around 1,000 years ago, what triggered the observed cultural and demographic transition?'"
Comment: there is no note of intermarriage of the two groups. Another comparative example is Fiji which has a Fijian and an Asian Indian admixture, with the Indians arriving is past few centuries. It is amazing how humans migrate long distances to unknown places by rafts/boats/large canoes.
Human evolution: gestation rates and teeth
by David Turell , Tuesday, November 08, 2022, 23:18 (744 days ago) @ David Turell
A comparison to other early forms:
https://phys.org/news/2022-11-relationship-teeth-evolution-pregnancy.html
"Humans have the highest prenatal growth rate of all extant primates, but how this exceptional rate came about has been a mystery up to now. Leslea Hlusko, a scientist at the Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), has participated in a study led by Tesla Monson, a paleoanthropologist at Western Washington University (WWU) in the United States), looking at teeth, prenatal growth rates, and the evolution of pregnancy. This research has uncovered a key piece of this jigsaw in an unexpected place: the relative sizes of fossilized molars.
***
"The results indicate that the hominids reached a prenatal growth rate setting them apart from all other apes between one million and a half million years ago, long before the human species itself evolved (between 300,000 and 200,000 years ago). (my bold)
"The prenatal growth rate is closely related to endocranial volume, and surprisingly, to the variation in the proportions of the molars. "This shows that the teeth can be an indicator both of the prenatal growth rate and the size of the brain, which is of special importance for our ability to study the gestational development of our human ancestors, because dental remains are the most abundant parts in the fossil record," says Hlusko.
"This discovery of the relationship between the proportions of the molars and prenatal growth rates has raised many new questions for evolution researchers, such as comprehension of the underlying genetic mechanisms. Another of the key issues is whether this is also found in other mammals.
"'While I don't think that our humanity can be reduced solely to the teeth, I do believe that part of it is recorded in our teeth. This work opens a window for studies of pregnancy and gestation. We can take dental material from human ancestors and other fossil primates to find out what their pregnancies were like," concludes Monson."
Comment: once the path to sapiens appeared it moved rather rapidly. Note the bold.
Human evolution: eight million on the way to ten
by David Turell , Monday, November 14, 2022, 21:25 (738 days ago) @ David Turell
edited by David Turell, Monday, November 14, 2022, 21:33
And the constant worry about enough food:
https://www.nationalgeographic.com/environment/article/the-world-now-has-8-billion-peop...
'We’ve added our most recent one billion more just since the first term of U.S. President Barack Obama. A mere dozen years after reaching seven billion, the planet most likely will surpass eight billion people sometime around mid-November, the United Nations estimates based on its best demographic projections.
"The actual timing, however, is uncertain. In parts of the world, census data is decades old. During COVID-19 it was virtually impossible for some countries to record every death. Even sophisticated computer models may be off by a year or more. It’s not as if anyone has done a global person-by-person head count.
"But the UN is declaring November 15 as the “Day of Eight Billion” because there is no mistaking the import of this moment. Humans everywhere are living longer, thanks to better health care, cleaner water, and improvements in sanitation, all of which have reduced the prevalence of disease. Fertilizers and irrigation have boosted crop yields and improved nutrition. In many countries, more children are being born, and far fewer are dying.
***
"The risks and opportunities of our population boom and parallel resource crisis depend largely on decisions we’ve not yet made. Which will control our future more—the billions of mouths we’ll have to feed, or the billions more brains we could employ to do so?
***
“'So far, the overall experience is that the world has been successful in adapting and finding solutions to our problems,” Gerland says. “I think we need to be somewhat optimistic.”
***
"Food security is already a concern. More than one-third of the country lives in extreme poverty, a greater number than any other country, including India, which is six times larger. A third of all households include one adult who must skip meals at times for the family to survive. (my bold)
***
"Currently at 216 million , the country’s population by some estimates could quadruple by the end of the century. By then it could have more people than China, which has 10 times more land. But that all depends on childbirth rates. All these projections are driven by assumptions, and the reality could be much different. (I think this is an error, from Wikipedia it given: 'The current population of India is 1,411,977,328 as of Saturday':
https://www.worldometers.info/world-population/india-population/ )
"The UN, a group of researchers at the University of Washington in Seattle, and other experts in Vienna, Austria, tend mostly to agree on what the next quarter century holds. Based on past events, at least, few expect another deadly global pandemic quite so soon. Despite crises like the war in Ukraine, neither do demographers yet foresee planet-wide mass migration by mid-century. Most experts see the population topping nine billion roughly by then.
"After that, projections vary greatly. A few years ago, the UN estimated that by 2100, the globe’s population could balloon to 11 billion. Earlier this year, it revised those estimates downward, to about 10.4 billion, thanks to progress in reducing the average number of children born per family. At the International Institute for Applied Systems Analysis, in Vienna, researchers in 2018 projected the population could rise to 9.7 billion in 2070 and then fall back to around 9 billion by century’s end. They used different assumptions, largely by asking global experts to weigh in. “The main story is not just about fertility but about progress in fighting child and infant mortality,” says Anne Goujon, population program director for IIASA.
***
"And aside from global population estimates, climate change and politics also will likely greatly influence migration between countries. Population in the U.S. and Western Europe has been largely sustained by immigration, but it has become a political hot button. Other countries with declining populations, such as Japan, have been even more reluctant to welcome immigrants.
"Yet the lopsided trends, between booming and declining populations, exacerbated by climate change, will almost certainly increase migration pressure almost everywhere.
“'The only way we can get out of this demographic imbalance,” Vollset says, “is well-managed international collaboration.'”
Comment: note my bold. Both God and we know how important this problem will be. God anticipated it by providing us with a current huge bush of life, which can be an adequate ecosystem for us if managed properly. dhw will scurry to agree, as he has done in the past, and immediately complain about all the necessary dead ends in evolution that acted as ecosystems to feed the burgeoning bush on the way to current size.
Human evolution: Neanderthal cooking like humans
by David Turell , Thursday, November 24, 2022, 15:15 (728 days ago) @ David Turell
Another recent find:
https://www.haaretz.com/archaeology/2022-11-23/ty-article/neanderthals-used-same-cookin...
"Now a new paper by Ceren Kabukcu and colleagues in the journal of Antiquity shows that the technique of charring objectionable vegetables to detoxify them and render them toothsome goes back tens of thousands of years, and was apparently even used by Neanderthals in Iraq.
***
"Sites from the Middle Paleolithic onward show evidence of consumption of bitter wild almonds, a rich source of cyanide; tannin-rich wild pistachios from terebinth trees, which reportedly taste like turpentine; bitter mustard leaves; and wild pulses including said vetch, some of which abound in neurotoxins. All need multiple steps of preparation to render them edible, or at least not deadly.
"The inference, says the team: foragers as of the Middle Paleolithic onward, sapiens or otherwise, must have developed preparation and cooking techniques to render these plants safe to eat.
***
"In fact, the charred plants at Shanidar are among the earliest finds of their kind discovered to date in southwest Asia and Europe, the researchers say.
***
"Shanidar in Iraq is famous for its occupation by Neanderthals who may have buried their dead with flowers. One of the layers to feature charred veg aggregate dates to the Middle Paleolithic. Five more surfaced in samples from the Upper Paleolithic about 42,500 to 35,000 years ago. At the very least, the earliest burned-veg mush there was cooked by Neanderthals about 75,000 to 70,000 years ago."
Comment: Neanderthals are becoming more and more human-like
Human evolution: specific DNA sequences
by David Turell , Thursday, November 24, 2022, 19:11 (728 days ago) @ David Turell
How DNA changed to drive human ecvolution:
https://www.sciencedaily.com/releases/2022/11/221123114249.htm
"A team of Duke researchers has identified a group of human DNA sequences driving changes in brain development, digestion and immunity that seem to have evolved rapidly after our family line split from that of the chimpanzees, but before we split with the Neanderthals.
Our brains are bigger, and are guts are shorter than our ape peers.
"A lot of the traits that we think of as uniquely human, and human-specific, probably appear during that time period," in the 7.5 million years since the split with the common ancestor we share with the chimpanzee, said Craig Lowe, Ph.D., an assistant professor of molecular genetics and microbiology in the Duke School of Medicine.
"Specifically, the DNA sequences in question, which the researchers have dubbed Human Ancestor Quickly Evolved Regions (HAQERS), pronounced like hackers, regulate genes. They are the switches that tell nearby genes when to turn on and off. The findings appear Nov.23 in the journal Cell.
"The rapid evolution of these regions of the genome seems to have served as a fine-tuning of regulatory control, Lowe said. More switches were added to the human operating system as sequences developed into regulatory regions, and they were more finely tuned to adapt to environmental or developmental cues. By and large, those changes were advantageous to our species.
"'They seem especially specific in causing genes to turn on, we think just in certain cell types at certain times of development, or even genes that turn on when the environment changes in some way," Lowe said.
"A lot of this genomic innovation was found in brain development and the GI tract. "We see lots of regulatory elements that are turning on in these tissues," Lowe said. "These are the tissues where humans are refining which genes are expressed and at what level."
"Today, our brains are larger than other apes, and our guts are shorter. "People have hypothesized that those two are even linked, because they are two really expensive metabolic tissues to have around," Lowe said. "I think what we're seeing is that there wasn't really one mutation that gave you a large brain and one mutation that really struck the gut, it was probably many of these small changes over time."
***
"'So, we know the Neanderthal sequence, but let's test that Neanderthal sequence and see if it can really turn on genes or not," which they did dozens of times.
"'And we showed that, whoa, this really is a switch that turns on and off genes," Lowe said. "It was really fun to see that new gene regulation came from totally new switches, rather than just sort of rewiring switches that already existed.'"
Comment: other studies of these regions have shown they sped up our evolution. Not surprising that we have special genes when we are so special.
Human evolution: Neanderthal cooking like humans
Neanderthal cooking like humans
DAVID: Neanderthals are becoming more and more human-like.
In view of the ever increasing number of common cultural activities, and bearing in mind the fact that Neanderthals and modern sapiens actually interbred, I feel very uncomfortable at the mere suggestion that they were not human. It seems to suggest that they were some kind of ape. I’m uncomfortable because we live in a world that is rife with racial prejudice, and although of course your comment is not meant in any way to be offensive, it is reminiscent of historical and still current attitudes which I’m sure you detest as much as I do. You may feel that I’m being oversensitive, but all the same, as a favour to me, I’d be grateful if you would allow me at least to change the heading to “modern humans”. I can also edit your comment to “more and more like modern humans” if you would like me to.
Human evolution: Neanderthal cooking like humans
by David Turell , Friday, November 25, 2022, 17:11 (727 days ago) @ dhw
Neanderthal cooking like humans
DAVID: Neanderthals are becoming more and more human-like.
dhw: In view of the ever increasing number of common cultural activities, and bearing in mind the fact that Neanderthals and modern sapiens actually interbred, I feel very uncomfortable at the mere suggestion that they were not human. It seems to suggest that they were some kind of ape. I’m uncomfortable because we live in a world that is rife with racial prejudice, and although of course your comment is not meant in any way to be offensive, it is reminiscent of historical and still current attitudes which I’m sure you detest as much as I do. You may feel that I’m being oversensitive, but all the same, as a favour to me, I’d be grateful if you would allow me at least to change the heading to “modern humans”. I can also edit your comment to “more and more like modern humans” if you would like me to.
We can differentiate the two types. In my view 'human' means the type named 'sapiens'. Neanderthals have their own separate identity and their own form of 'humanness'. They left 'apehood' long ago. Yes, you are oversensitive. Our followers are educated enough understand our proper level of discussion.
Human evolution: Neanderthal cooking like humans
DAVID: Neanderthals are becoming more and more human-like.
dhw: In view of the ever increasing number of common cultural activities, and bearing in mind the fact that Neanderthals and modern sapiens actually interbred, I feel very uncomfortable at the mere suggestion that they were not human. It seems to suggest that they were some kind of ape. I’m uncomfortable because we live in a world that is rife with racial prejudice, and although of course your comment is not meant in any way to be offensive, it is reminiscent of historical and still current attitudes which I’m sure you detest as much as I do. You may feel that I’m being oversensitive, but all the same, as a favour to me, I’d be grateful if you would allow me at least to change the heading to “modern humans”. I can also edit your comment to “more and more like modern humans” if you would like me to.
DAVID: We can differentiate the two types. In my view 'human' means the type named 'sapiens'. Neanderthals have their own separate identity and their own form of 'humanness'. They left 'apehood' long ago. Yes, you are oversensitive. Our followers are educated enough understand our proper level of discussion.
They ARE named sapiens. The full name given to the species is Homo sapiens neanderthalensis. My point is the same as yours: that they left apehood long ago, and that is why we should not describe them as being “humanlike”. They WERE human. However, we’ll leave it there. If there are any “followers”, they will draw their own conclusions.
Human evolution: Neanderthal cooking like humans
by David Turell , Saturday, November 26, 2022, 16:13 (726 days ago) @ dhw
DAVID: Neanderthals are becoming more and more human-like.
dhw: In view of the ever increasing number of common cultural activities, and bearing in mind the fact that Neanderthals and modern sapiens actually interbred, I feel very uncomfortable at the mere suggestion that they were not human. It seems to suggest that they were some kind of ape. I’m uncomfortable because we live in a world that is rife with racial prejudice, and although of course your comment is not meant in any way to be offensive, it is reminiscent of historical and still current attitudes which I’m sure you detest as much as I do. You may feel that I’m being oversensitive, but all the same, as a favour to me, I’d be grateful if you would allow me at least to change the heading to “modern humans”. I can also edit your comment to “more and more like modern humans” if you would like me to.
DAVID: We can differentiate the two types. In my view 'human' means the type named 'sapiens'. Neanderthals have their own separate identity and their own form of 'humanness'. They left 'apehood' long ago. Yes, you are oversensitive. Our followers are educated enough understand our proper level of discussion.
dhw: They ARE named sapiens. The full name given to the species is Homo sapiens neanderthalensis. My point is the same as yours: that they left apehood long ago, and that is why we should not describe them as being “humanlike”. They WERE human. However, we’ll leave it there. If there are any “followers”, they will draw their own conclusions.
Thank you for giving the full title for Neanderthals. I am educated.
Human evolution: birth canal and tooth development
by David Turell , Saturday, November 26, 2022, 19:20 (726 days ago) @ David Turell
A new very complete study:
https://www.sciencealert.com/theres-a-weird-link-between-teeth-and-the-evolution-of-pre...
"Human babies pack a lot of growth into those nine months between conception and birth to give them and their meaty, complex brains a chance at survival.
"Just how evolution came to grant humans such a comparatively rapid prenatal growth rate has never been clear.
"Given how critical brain growth is to early human development, and head size, in turn, influences the size of our jaws, researchers suspected teeth may hold some valuable information on our ancestors' pregnancies.
"Teeth begin to form at around 6 weeks of gestation but don't develop their hardened exterior layers until the second trimester. From there, the growing layers can retain records of their life history, from weaning to sexual activity.
***
"Hlusko, Western Washington University paleoanthropologist Tesla Monson, and colleagues measured the ratios between third and first molar length in primate species still alive today, to obtain the relative molar size.
"They found that prenatal growth rate, head size, and relative molar size did indeed all follow the same pattern across all these primates. So they used this established pattern to delve into our evolutionary history, analyzing primate fossils spanning between 6 million to 12,000 thousand years ago, covering 13 hominid species.
"Both cranial and dental remains indicate that prenatal growth rates increased over the last 6 million years. Along with fossilized pelvis and head anatomy, these findings support the theory that long human-like pregnancies evolved within the last few hundred thousand to million years, during the Pleistocene.
As primates transitioned to walking on two legs in the Early Pliocene around 5.333 million years ago, signs of which were starting to be visible in Australopithecus and Ardipithecus fossils, their prenatal growth rates were still more similar to the monkeys and apes alive today, than to ours.
"But by the evolution of Homo erectus in the Early Pleistocene, about 2,580,000 years ago, there was a definite shift, which was also reflected in their pelvic anatomy.
"'Changing pelvic anatomy, endocranial volume, and predicted prenatal growth rates all provide independent lines of evidence that support human-like pregnancy and birth evolving in the Pleistocene in the later Homo species, before the emergence of Homo sapiens," the team writes in their paper.
"These changes coincide with expanding grasslands and herbivore populations, which may have provided the Homo genus with the extra resources needed to fuel the increase in neonatal size and longer maternal investment.
"Advancements in tools that also occurred across this time may be a reflection of our ancestor's growing brain size, as well as the likely evolution of group hunting, which in turn would have provided even more resources."
Comment: of course, pelvic changes accommodated large head sizes. How did such coordination happen? Natural changes are very unlikely. Design is better theory.
Human evolution: a fossil with unknown DNA
by David Turell , Sunday, November 27, 2022, 16:43 (725 days ago) @ David Turell
A female from a Siberian cave, about 50,000 years ago:
https://www.sciencealert.com/an-ai-found-an-unknown-ghost-ancestor-in-the-human-genome?...
"Nobody knows who she was, just that she was different: A teenage girl from over 50,000 years ago of such odd uniqueness she appeared to be a 'hybrid' ancestor to modern humans that scientists hadn't seen before.
"Only recently, researchers have uncovered evidence she wasn't alone. In a 2019 study analyzing the tangled mess of humanity's prehistory, scientists used artificial intelligence (AI) to identify an unknown human ancestor species that modern humans encountered – and shared dalliances with – on the long trek out of Africa millennia ago.
***
"Up until recently, these occasional sexual partners were thought to include Neanderthals and Denisovans, the latter of which were unknown until 2010.
"But in this study, a third ex from long ago was isolated in Eurasian DNA, thanks to deep learning algorithms sifting through a complex mass of ancient and modern human genetic code.
"Using a statistical technique called Bayesian inference, the researchers found evidence of what they call a "third introgression" – a 'ghost' archaic population that modern humans interbred with during the African exodus.
***
"Also in 2018, another team of researchers identified evidence of what they called a "definite third interbreeding event" alongside Denisovans and Neanderthals, and a pair of papers published in early 2019 traced the timeline of how those extinct species intersected and interbred in clearer detail than ever before.
"There's a lot more research to be done here yet. Applying this kind of AI analysis is a decidedly new technique in the field of human ancestry, and the known fossil evidence we're dealing with is amazingly scant.
"But according to the research, what the team has found explains not only a long-forgotten process of introgression – it's a dalliance that, in its own way, informs part of who we are today.
"'We thought we'd try to find these places of high divergence in the genome, see which are Neanderthal and which are Denisovan, and then see whether these explain the whole picture," Bertranpetit told Smithsonian.
"'As it happens, if you subtract the Neanderthal and Denisovan parts, there is still something in the genome that is highly divergent.'"
Comment: We have discussed before the large bush of homo forms that preceded the final arrival of H. sapiens. What seems to be a pattern is when a type of animal appears it spreads out into many species, as dinosaurs, whales, birds, etc. show. But in this case only one remains after a burst of forms. Chance or guided by God?
Human evolution: Neanderthal cooking like humans
by David Turell , Thursday, December 01, 2022, 23:58 (720 days ago) @ David Turell
Another article:
https://www.smithsonianmag.com/smart-news/neanderthals-cooked-up-complex-and-tasty-meal...
“'This study points to cognitive complexity and the development of culinary cultures in which flavors were significant from a very early date,” says Kabukcu in the statement. “Our work conclusively demonstrates the complexities in the early hunter-gatherer diet which are akin to modern food preparation practices. For example, wild nuts and grasses were often combined with pulses, like lentils, and wild mustard.”
"John McNabb, an archaeologist at the Centre for the Archaeology of Human Origins at the University of Southampton who was not involved in the research, tells CNN that our knowledge of the Neanderthal diet has greatly evolved “as we move away from the idea of [Neanderthals] just consuming huge quantities of hunted game meat.”
“'This study points to cognitive complexity and the development of culinary cultures in which flavors were significant from a very early date,” says Kabukcu in the statement. “Our work conclusively demonstrates the complexities in the early hunter-gatherer diet which are akin to modern food preparation practices. For example, wild nuts and grasses were often combined with pulses, like lentils, and wild mustard.”
"John McNabb, an archaeologist at the Centre for the Archaeology of Human Origins at the University of Southampton who was not involved in the research, tells CNN that our knowledge of the Neanderthal diet has greatly evolved “as we move away from the idea of [Neanderthals] just consuming huge quantities of hunted game meat.'”
Comment: Yep, more and more like us!
Human evolution; Early fire use
by David Turell , Saturday, December 03, 2022, 01:05 (719 days ago) @ David Turell
In South African Naledi:
https://www.sciencenews.org/article/homo-naledi-fire-hominid-cave-human-evolution
"An ancient hominid dubbed Homo naledi may have lit controlled fires in the pitch-dark chambers of an underground cave system, new discoveries hint.
"Researchers have found remnants of small fireplaces and sooty wall and ceiling smudges in passages and chambers throughout South Africa’s Rising Star cave complex, paleoanthropologist Lee Berger announced in a December 1 lecture hosted by the Carnegie Institution of Science in Washington, D.C.
“'Signs of fire use are everywhere in this cave system,” said Berger, of the University of the Witwatersrand, Johannesburg.
"H. naledi presumably lit the blazes in the caves since remains of no other hominids have turned up there, the team says. But the researchers have yet to date the age of the fire remains. And researchers outside Berger’s group have yet to evaluate the new finds.
"H. naledi fossils date to between 335,000 and 236,000 years ago, around the time Homo sapiens originated. Many researchers suspect that regular use of fire by hominids for light, warmth and cooking began roughly 400,000 years ago
***
"Still, the main challenge for investigators will be to date the burned wood and bones and other fire remains from the Rising Star chambers and demonstrate that the fireplaces there come from the same sediment layers as H. naledi fossils, says paleoanthropologist W. Andrew Barr of George Washington University in Washington, D.C., who wasn’t involved in the work."
Comment: it is always interesting to learn how ancient Homos learned to deal with fire. The naledi don't fit the picture with erectus in the bush of homos/hominins.
Human evolution; Denisovan DNA in Papuans
by David Turell , Thursday, December 08, 2022, 20:46 (714 days ago) @ David Turell
Helps with immunity:
https://www.scientificamerican.com/article/dna-from-extinct-human-relative-may-have-sha...
"Thousands of years ago, the ancestors of modern humans met and mated with Neandertals—and also with their close cousins and contemporaries, Denisovans. Though both Neandertals and Denisovans later went extinct (with Denisovans possibly sticking around until as recently as 15,000 years ago), billions of people around the world still carry the proof of these interactions in their DNA.
"Why these genetic fragments from extinct humans have stuck around isn’t entirely clear. But the new study, published on Thursday in PLOS Genetics, finds disease resistance might have been involved. The research—conducted by Irene Gallego Romero, a human evolutionary geneticist at the University of Melbourne in Australia, and her colleagues—suggests that certain mutations from long-gone Denisovans may help today’s Papuans fend off viral infections.
***
"The Indigenous people of New Guinea and Australia have some of the highest concentrations of Denisovan DNA in the world, with an average of around 5 percent of this DNA in their respective genomes. So Gallego Romero and her colleagues decided to sort through the genomes of 56 Papuans to examine what parts of their genetic sequences retained Denisovan DNA.
***
"In particular, the Denisovan mutations were in regions that control genes involved in responding to viral infection.
***
"Denisovans in New Guinea may have had tens of thousands of years longer to adapt to local diseases before modern humans showed up. Thus, the descendants of people who bred with Denisovans may have carried mutations that helped them overcome the worst of these illnesses.
"Such research shows why studying diverse groups can help reveal how humans adjusted to new environments and can “highlight how human diversity is important for adaptation,” says Lluis Quintana-Murci, a population geneticist at France’s Pasteur Institute, who was not involved with the new study." (my bold)
Comment: each group of 'homos' in the past were diverse. The bold supports my thought that God created this diversity to mold the eventual human immunity system to make it broader. WE know Neandertal genes in our DNA support immune activity.
Human evolution; leaving Africa
by David Turell , Thursday, December 15, 2022, 19:22 (707 days ago) @ David Turell
Mediterranean sailing evidence:
https://www.haaretz.com/archaeology/2022-12-15/ty-article/hominins-were-sailing-the-med...
"However, there is growing evidence that several areas that were islands for hundreds of thousands or even millions of years were occupied by hominins, who must have braved the waves to get there. This is now argued to be the case with the Aegean Islands, an archipelago of hundreds of islands between Greece and Turkey, including favorite holiday destinations such as Crete, Mikonos and Santorini.
"Strong evidence of early hominin habitation first emerged about a decade ago when archaeologists on Crete found thousands of flint tools dated to more than 130,000 years ago, and possibly as old as 700,000 years. These artifacts were made in the Acheulean style, a distinctive stone tool industry first developed in Africa by Homo erectus, the first hominin to leave humanity’s evolutionary cradle and spread across Eurasia starting some 1.9 million years ago.
***
"The researchers reconstructed the shoreline of the Aegean Islands and surrounding mainland over the last 450,000 years. This was done by combining data from ancient river deltas, which reveal changes in sea levels, with the known subsidence rate, caused by tectonic plate activity, of the Aegean Islands.
***
"Given that different hominins often used the same stone tool technologies it is difficult to determine who exactly the first colonizers of the Aegean Islands were without finding any human remains. However, the most likely candidates would be Erectus or one of his descendants, such as Homo heidelbergensis, which mostly populated Europe, or Nesher Ramla Homo, a recently proposed Middle Pleistocene inhabitant of modern-day Israel and the Levant.
***
“'Although I fully endorse the hypothesis that sea crossing was not necessarily a Homo sapiens skill and innovation, but that other large-brained Middle Pleistocence species may also have had it, the data offered in the paper do not provide conclusive evidence to that effect,” Galanidou tells Haaretz. She notes that the oldest known Sapiens fossils date to around 300,000 years ago – not too far from the time frame of 450,000 onwards that was the focus of the new study – so we cannot rule out that those first Aegean inhabitants were just early modern humans.
"Ferentinos says his study didn’t go beyond the half a million year mark because we don’t yet have reliable data for how the shorelines of Greece and Turkey looked like before then. However, he and his colleagues are convinced that the evidence for sea voyages by pre-Sapiens hominins in the Aegean is strong and is also indirectly confirmed by the recent discovery of million-year-old prehistoric tools linked to Homo erectus in Spain.
"This is earlier than other Erectus finds in Western and Eastern Europe, suggesting that hominins may have reached the Iberian Peninsula first by crossing the Strait of Gibraltar, rather than by travelling by land from the east, Ferentinos says.
“'Traditionally we think Erectus only left Africa through the Sinai Peninsula and then the Levant, but then we have to ask ourselves how they got to Spain before reaching the rest of Europe,” he says. “The most plausible solution is that they crossed at Gibraltar. I think we need to rethink what we know about human dispersal not just in Greece but around the world.'”
Comment: perhaps our early ancestors were master sailors. God did not control their travels.
Human evolution; bipedalism debate
by David Turell , Friday, December 16, 2022, 20:13 (706 days ago) @ David Turell
Does less trees drive one to walk? Notso sure:
https://www.sciencealert.com/early-humans-may-have-learned-to-walk-while-still-in-the-t...
"Bipedalism – walking upright on two legs – is a defining feature of humans, thought to have developed in our ancient relatives as they crept away from the woodlands to take advantage of open spaces.
"A new study exploring the behavior of wild chimpanzees suggests the evolution of bipedalism may in fact have been a strategy that first emerged while still moving about the branches of trees.
"Researchers have long wondered if a change in habitat drove our ancestors towards bipedalism, or if they evolved the ability to walk on two feet to forage in the forests they'd long inhabited, a skill which later came in handy traversing the expanses of an open grassland.
***
"The study documented the behaviors of wild chimpanzees (Pan troglodytes schweinfurthii) in the Issa Valley, in western Tanzania. The Issa Valley is a savanna mosaic region in the East African Rift Valley, similar to the habitat where early hominins once roamed.
"Chimpanzees living in similar habitats to those of our earliest human ancestors give scientists an opportunity to investigate the ecological drivers of bipedalism. The movements and postures of the Issa Valley chimpanzees were compared with previous study data on chimpanzees living in dense forest areas of Africa.
"When comparing the behavior observed in Issa Valley chimpanzees to that of entirely forest-dwelling chimps in other parts of Africa, the researchers found that despite their savanna mosaic habitat, the Issa chimpanzees were not more terrestrial. They spent the same amount of their time in trees as the chimpanzees living in heavy forests.
***
"More than 85 percent of the observed bipedalism events among the Issa Valley chimpanzees took place in trees, mostly when the chimps were foraging for food. The authors note this is a surprising find as much of the evolutionary pressure for bipedalism is thought to be associated with ground-based activity, like carrying objects or looking over high grass.
"'Our study suggests that the retreat of forests in the late Miocene-Pliocene era around five million years ago and the more open savanna habitats were in fact not a catalyst for the evolution of bipedalism," says co-author, UCL biological anthropologist Alex Piel.
"'Instead, trees probably remained essential to its evolution – with the search for food-producing trees a likely driver of this trait."
"Whether our own ancestors behaved in a similar manner, and how a shuffle along the branches developed into a stroll across the savannah, will require further research.
"But if our chimpanzee cousins are anything to go by, our ancestors may have been prepared to hit the ground running when the time came to leave the trees."
Comment: we are back to chicken and egg. If the trees got very scarce, they would be forced to get down and walk. This tentatively supports my theory that god speciates and prepared us to walk in advance
Human evolution; tiny new genes identified
by David Turell , Friday, December 23, 2022, 18:26 (699 days ago) @ David Turell
Difficult to find:
https://www.sciencealert.com/tiny-new-genes-appearing-in-human-dna-show-how-were-still-...
"Researchers from Biomedical Sciences Research Center "Alexander Fleming" (BSRC Flemming) in Greece and Trinity College Dublin, Ireland, have identified 155 genes in our genome that emerged from small, non-coding sections of DNA. Many appear to play a critical role in our biology, revealing how completely novel genes can rapidly evolve to become essential.
"New genes typically arise through well known mechanisms like duplication events, where our genetic machinery accidently produces copies of pre-existing genes that can end up suiting new functions over time.
But the 155 microgenes pinpointed in this study seem to have appeared from scratch, in stretches of DNA that didn't previously contain the instructions that our bodies use to build molecules.
"Since the proteins these new genes are thought to encode would be incredibly tiny, these DNA sequences are hard to find and difficult to study, and therefore are often overlooked in research.
***
"The team behind this new study subsequently created a genetic ancestral tree to compare those tiny sequences found in our genomes against those in 99 other vertebrate species, tracking the evolution of the genes over time.
"Some of the new 'microgenes' identified in this new study can be tracked all the way back to the earliest days of mammals, while others are more recent additions. Two of the genes identified by the study seem to have emerged since the human-chimpanzee split, the researchers found.
"'We sought to identify and examine cases in the human lineage of small proteins that evolved out of previously noncoding sequences and acquired function either immediately or shortly thereafter," the team writes in their published paper.
"'This is doubly important: for our understanding of the intriguing, and still largely mysterious phenomenon of de novo gene birth, but also for our appreciation of the full functional potential of the human genome."
"Microproteins are already known to have a diverse range of functions from helping to regulate the expressions of other genes to joining forces with larger proteins including our cell membranes. However, while some microproteins perform vital biological tasks, others are plain useless.
"'When you start getting into these small sizes of DNA, they're really on the edge of what is interpretable from a genome sequence, and they're in that zone where it's hard to know if it is biologically meaningful," explains Trinity College Dublin geneticist Aoife McLysaght.
"One gene with a role in constructing our heart tissue emerged when an ancestor common to humans and chimps branched off from the gorilla's ancestry. If indeed this microgene emerged in the last few million years, it's striking evidence that these evolving parts of our DNA can quickly become essential to the body.
"The researchers then probed the sequences' functions by deleting genes, one by one, in lab-grown cells. Forty-four of the cell cultures went on to show growth defects, confirming those now missing sections of DNA play critical roles in keeping us functioning.
***
"Exactly how the spontaneous creation of new genes within the non-coding region happens is not yet clear, but with our newfound ability to track these genes, we may be closer to finding out. (my bold)
"'If we're right in what we think we have here, there's a lot more functionally relevant stuff hidden in the human genome," says McLysaght."
Comment: it is not surprise. These are small adaptive and useful but overall, we are the same species. This is more than epigenetic codes. The bold above is a key to determining if God is at work or if there is a built-in system such as dhw favors.
Human evolution; new genes identified for body fur
by David Turell , Tuesday, January 10, 2023, 16:38 (681 days ago) @ David Turell
We do carry the genes for full body hair:
https://www.sciencealert.com/humans-still-have-the-genes-for-a-full-coat-of-fur-scienti...
"Fur is a defining feature of being a mammal. But bald is beautiful for several mammalian weirdos, including dolphins, mole rats, elephants, and of course, humans. Not to mention a handy adaptation.
"Yet all our ancestors had plenty of fur. According to a new study on relatively hairless mammals, we still have the means to be hirsute. Those genes, it seems, have simply been switched off.
***
"The selection pressures for this lack of hair are just as varied as the species that have lost their fuzz. For elephants, it's a way to lose heat faster; for marine mammals, being sleeker means less resistance moving in the water; and for us, well, there are possibly multiple contributing pressures, including thermoregulation and reduction of parasites.
"Despite these differences, Kowalczyk and colleagues found the genetic changes in furless species mostly arose from mutations in the same sets of genes.
"Many of these mutation-gathering genes were related to the structure of the hair itself, like genes that encode for keratin proteins, the sequences that regulate the development of hair.
***
"While we still retain many of our ancestral fur-coding genes, their regulation dials have been set to 'off' through the accumulation of these mutations.
"The team also identified hundreds of new hair-related regulatory genes and some potential new hair-coding genes. These may prove important for people trying to recover lost hair due to disorders or chemotherapy."
Comment: hair is a different issue when considering adaptations with loss of genes that is the reason for the change, as Behe has documented. Here the genes are present but silenced. I do not understand why different mechanisms are used. Mammals without hair must have that adaptation to fit the environment in which they live. I'm stuck with simply understanding it is God's choice, but do not see His reasoning.
Human evolution; tiny new genes identified
by David Turell , Thursday, January 12, 2023, 22:59 (679 days ago) @ David Turell
In noncoding areas of DNA:
https://www.the-scientist.com/news-opinion/humans-are-still-evolving-thanks-to-microgen...
"Humans are still evolving new genes, according to a study published in Cell Reports on December 20. As our lineage evolved, at least 155 human genes sprung up from DNA regions previously thought of as “junk,” including two human-specific genes that emerged since humans branched off from chimpanzees around 4 to 6 million years ago, the researchers report.
***
"The genes described in the new study went undiscovered for so long because they’re teeny: They top out at about 300 nucleotides in length, while a typical human gene is 10 to 15,000 base pairs on average. Even though they possess start and stop codons that allow them to be read by cells’ transcriptional machinery just like traditional genes, these so-called microgenes—sometimes called short open reading frames (sORFs)—have long been assumed to be nonfunctional, Saghatelian explains.
"But recent studies found that knocking out sORFs stunts cell growth, indicating they’re important after all. One 2020 study, for example, found hundreds of functional sORFs in human cells, both in the coding and noncoding regions of the genome. The number was intriguing to Nikolaos Vakirlis, a computational evolutionary biologist at Biomedical Sciences Research Center Alexander Fleming in Vari, Greece, and he and his colleagues felt compelled to investigate these genetic oddities further, launching what became the newly published research. “We find species-specific genes everywhere,” Vakirlis says. “So there has to be an evolutionary route for them to originate.” (my bold)
***
"Through this process, the team identified 155 microgenes that all vertebrates share. Forty-four of these are critical for cell growth, according to data from the previous study. Three have disease markers associated with ailments such as muscular dystrophy, retinitis pigmentosa, and Alazami syndrome. The team also found one microgene—associated with human heart tissue—that cropped up after chimps and humans split off from gorillas about 7 to 9 million years ago.
"Intriguingly, Vakirlis and his colleagues found that these new genes had emerged from the noncoding regions of DNA, rather than by mutation or duplication of existing genes. While gene duplication is thought to be the main source of new genes in all species, the appearance of microgenes might explain how humans developed some uniquely human characteristics, as well as how other animals gained uniquely species-specific phenotypes.
"John Prensner, a physician at Dana Farber Cancer Institute who was not involved in the study, tells The Scientist; via email that “this [study] is really important work.” He explains that scientists have known about sORFs and other non-canonical open reading frames for some time, but hadn’t determined what they may do. He explains that microgenes are a potential route for evolution even today. They encode “proto-proteins,” or small proteins that organisms are beginning to try out. These proteins might go nowhere and be eliminated from the genome over time, but may also have a useful function and eventually become fixed in the genome.
Comment: This is microevolution in an established species. Humans are still typically humans. Thev study puts an end to any arguments for junk DNA
Human evolution; New Northeast genetic group
by David Turell , Friday, January 13, 2023, 16:37 (678 days ago) @ David Turell
edited by David Turell, Friday, January 13, 2023, 16:57
About 10,000 years ago showing Bering Sea migrations back and forth:
https://www.livescience.com/previously-unknown-hunter-gatherers-siberia?utm_term=C3CFD6...
"A genetic study has revealed the existence of a previously unknown hunter-gatherer group that lived in Siberia upwards of 10,000 years ago.
"The find was made during a genetic investigation of human remains in North Asia dating from as far back as 7,500 years ago. The study also revealed that gene flow of human DNA not only traveled from Asia to the Americas — as was previously known — but also in the opposite direction, meaning people were moving back and forth like ping pong balls along the Bering Land Bridge.
"Furthermore, the team examined the remains of an ancient shaman who lived about 6,500 years ago in western Siberia. This spot is more than 900 miles (1,500 kilometers) west of the group that he had genetic ties with, according to the new genetic analysis.
***
"Many of the individuals were found in an area known as the Altai, a crossroad for migrations between northern Siberia, Central Asia and East Asia for millennia, located near where modern-day Russia, China, Mongolia and Kazakhstan come together. Previous research in the Altai revealed the first evidence of the mysterious and much older human lineage known as the Denisovans, who together with the Neanderthals are the closest extinct relatives of modern humans.
"The scientists discovered that a previously unknown group of hunter-gatherers in the Altai was "a mixture between two distinct groups that lived in Siberia during the last Ice Age," Posth said. DNA from these prehistoric hunter-gatherers was found in many later communities across North Asia, from the Bronze Age (about 3000 B.C. to 1000 B.C.) to the present day, "showing how great the mobility of those foraging communities was," he added.
"In addition, the researchers discovered multiple episodes of gene flow from North America to Asia over the past 5,000 years, with genes from the New World reaching Russia's Kamchatka Peninsula on the Pacific Ocean and central Siberia.
"'While there has been a lot of work showing flows of genetic ancestry into the Americas, there has been less evidence for backflow from the American continent to Eurasia," said Vagheesh Narasimhan(opens in new tab), a geneticist at the University of Texas at Austin, who did not participate in this study. "This work presents a new sample from northeastern Asia to support these results."
***
"Overall, the study shows that prehistoric groups were more connected than previously believed.
"All in all, "geographically distant hunter-gatherer groups showed evidence of genetic connections to a much larger extent than previously expected," Posth said. "This suggests that human migrations and admixtures [interbreeding between groups] were not the exception but the norm also for ancient hunter-gatherer societies.'"
Comment: this DNA identification shows relatively recent hybridization of modern humans. The mystery of exactly when humans reached North America is still unclear.
The source article:
https://www.cell.com/current-biology/fulltext/S0960-9822(22)01892-9?dgcid=raven_jbs_aip...
Human evolution; how DNA changed from Chimps
by David Turell , Saturday, January 14, 2023, 21:34 (677 days ago) @ David Turell
Has to do with HAR areas in DNA:
https://phys.org/news/2023-01-evolution-uniquely-human-dna.html
"Humans and chimpanzees differ in only one percent of their DNA. Human accelerated regions (HARs) are parts of the genome with an unexpected amount of these differences. HARs were stable in mammals for millennia but quickly changed in early humans. Scientists have long wondered why these bits of DNA changed so much, and how the variations set humans apart from other primates.
"Now, researchers at Gladstone Institutes have analyzed thousands of human and chimpanzee HARs and discovered that many of the changes that accumulated during human evolution had opposing effects from each other.
"This helps answer a longstanding question about why HARs evolved so quickly after being frozen for millions of years," says Katie Pollard, Ph.D., director of the Gladstone Institute of Data Science and Biotechnology and lead author of the new study published today in Neuron. "An initial variation in a HAR might have turned up its activity too much, and then it needed to be turned down."
***
"More recently, Pollard's group wanted to study how human HARs differ from chimpanzee HARs in their enhancer function. In the past, this would have required testing HARs one at a time in mice, using a system that stains tissues when a HAR is active.
"Instead, Whalen input hundreds of known human brain enhancers, and hundreds of other non-enhancer sequences, into a computer program so that it could identify patterns that predicted whether any given stretch of DNA was an enhancer. Then he used the model to predict that a third of HARs control brain development.
"'Basically, the computer was able to learn the signatures of brain enhancers," says Whalen.
"Knowing that each HAR has multiple differences between humans and chimpanzees, Pollard and her team questioned how individual variants in a HAR impacted its enhancer strength. For instance, if eight nucleotides of DNA differed between a chimpanzee and human HAR, did all eight have the same effect, either making the enhancer stronger or weaker?
***
"The idea that HAR variants played tug-of-war over enhancer levels fits in well with a theory that has already been proposed about human evolution: that the advanced cognition in our species is also what has given us psychiatric diseases.
"'What this kind of pattern indicates is something called compensatory evolution," says Pollard. "A large change was made in an enhancer, but maybe it was too much and led to harmful side effects, so the change was tuned back down over time—that's why we see opposing effects."
"If initial changes to HARs led to increased cognition, perhaps subsequent compensatory changes helped tune back down the risk of psychiatric diseases, Pollard speculates. Her data, she adds, can't directly prove or disprove that idea. But in the future, a better understanding of how HARs contribute to psychiatric disease could not only shed light on evolution, but on new treatments for these diseases.
"'We can never wind the clock back and know exactly what happened in evolution," says Pollard. "But we can use all these scientific techniques to simulate what might have happened and identify which DNA changes are most likely to explain unique aspects of the human brain, including its propensity for psychiatric disease."
Comment: I've presented HAR's in the past. I view this as a peek into how God programmed us.
Human evolution; new genes from non-coding DNA
by David Turell , Friday, January 13, 2023, 17:53 (678 days ago) @ David Turell
New research in Rhesus monkeys:
https://www.sciencemagazinedigital.org/sciencemagazine/library/item/13_january_2023/407...
"Biologists have shone a light on an evolutionary mystery: how stretches of seemingly useless DNA can become meaningful, protein-coding genes. New genes are known to arise when existing ones are accidentally duplicated, freeing one copy to evolve novel or additional functions. But some genes seem to evolve from stretches of DNA once disparaged as “junk.”
"Now, a study has identified mutations that play a key part in this process: They enable RNA encoded by this DNA to slip out of the cell nucleus into the cell cytoplasm, where it can be translated into a protein. The study highlights 74 human protein genes that appear to have evolved this way, including some that may have helped drive the evolution of our large and complex brains.
***
"A decade ago, Chuan-Yun Li, an evolutionary biologist at Peking University, and colleagues discovered that some human protein genes bear a striking resemblance to DNA sequences in rhesus monkeys that get transcribed into long noncoding RNAs (lncRNAs), which don’t make proteins or usually have any other purpose. How those stretches of monkey DNA could have become true protein-coding genes was a mystery, but Li’s postdoc, Ni A. An, discovered a clue.
"Many lncRNAs, An found, have a hard time exiting the nucleus and traveling to ribosomes, the organelles that translate messenger RNA (mRNA) into proteins. The researchers then searched for differences between protein-coding genes whose mRNA got out of the nucleus and DNA sequences whose RNAs did not. Stretches of DNA known as U1 elements seemed to be the key: When transcribed into RNA they make the strand too sticky to escape. In protein-coding genes, mutations have altered or eliminated the U1 elements to make the RNA less sticky.
“'This makes perfect sense because for an RNA to be translated, it needs to go the cytoplasm [where ribosomes are found] first,” says Maria Del Mar Albà, an evolutionary biologist at Hospital del Mar Medical Research Institute in Barcelona.
"In search of genes that originated this way, Li’s team scoured the human and chimpanzee genomes for protein-coding genes that had lncRNA counterparts in rhesus monkeys, as well as the crucial U1 element mutations. Dozens fit the bill, including nine that are active in the human brain. To learn what they do, Li’s collaborator Baoyang Hu, a neuroscientist from the Chinese Academy of Sciences Institute of Zoology, grew clumps of human brain tissue called cortical organoids with and without each of these genes. Two of them made the organoids grow slightly bigger than normal.
"When Hu introduced the genes into mice, their brains also grew larger and developed a bigger cortex, the wrinkly outer layer of the mammalian brain that in humans is responsible for high-level functions such as reasoning and language. One of the genes also caused the animals’ brains to develop more humanlike ridges and grooves, and mice that carried it performed better on tests of cognitive function and memory than mice lacking this gene. Li and Hu’s team says it will soon report these findings in Advanced Science.
***
"Long adds other reasons to be cautious about concluding the genes had a role in human brain expansion: Organoids are far simpler tissues than the brain itself, he notes, and human and mouse brains have evolved along very different paths.
"But Long doesn’t doubt that many key genes do emerge from noncoding sequences. His own group has found that most of the recognizable de novo genes in rice were once lncRNAs, and that lncRNAs also helped form new genes in bamboo."
Comment: Long non-coding RNA was a black-box area until this work showed how they contribute to new gene formation. This looks like dhw's wish for cells innate ability to do their own designing. which then brings up the issue of purpose in biology. To design requires first developing a theoretical purposeful goal, which can only come from mental activity. The only other way is to be given exquisitely detailed instructions to follow. So, we come back to my usual point: it is easier for God to do it Himself, than get involved with the rigmarole of providing a huge set of detailed instructions.
Human evolution; early bow hunting
by David Turell , Wednesday, February 22, 2023, 19:18 (638 days ago) @ David Turell
Arrow tips found about 54,000 years old:
https://www.sciencenews.org/article/homo-sapiens-archery-europe-neandertal
"Homo sapiens who reached Europe around 54,000 years ago introduced bows and arrows to that continent, a new study suggests.
"Researchers examined tiny triangular stone points and other artifacts excavated at a rock-shelter in southern France called Grotte Mandrin. H. sapiens on the move probably brought archery techniques from Africa to Europe, archaeologist Laure Metz of Aix-Marseille University in France and colleagues report February 22 in Science Advances.
“'Metz and colleagues demonstrate bow hunting [at Grotte Mandrin] as convincingly as possible without being caught bow-in-hand,” says archaeologist Marlize Lombard of the University of Johannesburg, who did not participate in the new study.
***
"Previous stone and bone point discoveries suggest that bow-and-arrow hunting originated in Africa between about 80,000 and 60,000 years ago. And previously recovered fossil teeth indicate that H. sapiens visited Grotte Mandrin as early as 56,800 years ago, well before Neandertals’ demise around 40,000 years ago and much earlier than researchers had thought that H. sapiens first reached Europe
***
"Lombard, the University of Johannesburg archaeologist, suspects that the first H. sapiens at the French rock-shelter hunted with bows and arrows as well as with spears, depending on where and what they were hunting. Earlier studies directed by Lombard indicated that sub-Saharan Africans similarly alternated between these two types of hunting weapons starting between about 70,000 and 58,000 years ago.
Comment: they had to have discovered archery at some point.
Human evolution; comparing sapiens and Neanderthal brains
by David Turell , Thursday, March 09, 2023, 19:04 (623 days ago) @ David Turell
Ours is smaller:
https://www.discovermagazine.com/the-sciences/brutes-and-brains-what-we-know-about-nean...
"Tradition says that Homo neanderthalensis and Homo sapiens were intellectually distinct. But archaeologists and anthropologists increasingly insist that the intellectual divide between the two species is shrinking.
"In fact, the traces of their ancient activities show more and more that the two species followed similar survival strategies. Residing in similar societies, they made similar sounds and manipulated similar tools. Apart from that, the most recent research shows that the two created similar art, too, signifying their shared taste for abstraction.
"But what about their brains? Was there anything in their anatomy that differentiated their thinking?
'Some specialists say yes. Working in the fields of paleontology, paleoneurology and paleogenetics, experts suspect that the slightest distinctions in the structure and development of the two species’ brains could’ve set their cognition apart in complex and consequential ways.
***
"Though the measurements aren’t always consistent and change over time, specialists say that the typical Neanderthal skull contained around 1500 cubic centimeters (or 51 ounces) of cerebral tissue, though the skulls of their more modern counterparts showed a smaller cranial capacity of only 1350 cubic centimeters (or 46 ounces).
"In addition to their size, Neanderthal brains and braincases were also slightly stretched, producing a strange, semi-spherical skull that terminated in a big bump toward the back. Termed the “occipital bun,” this bump was one of the first features of Neanderthal anatomy that experts discovered and described.
***
"Some studies suppose, for instance, that the structure of the Neanderthal skull meant that the H. neanderthalensis cerebellum was smaller than the H. sapiens cerebellum. A small cerebellum, these studies say, can cut a species’ capacity to learn and think logically, to process language, and to interact socially, which would all substantially impact its survival.
"Adding to this is an assortment of similar proposals about the peculiarities inside the Neanderthal mind. For instance, some paleontologists and paleoneurologists say that much more of the species’ brain was concentrated on controlling basic body movements, all thanks to the species’ bigger, bulkier bodies, which were more difficult to move than our own.
***
"Genetic analyses add additional support to the idea that the development of the Neanderthal brain differed from our own. In fact, though specialists traditionally stick to skulls in their attempts to study Neanderthal smarts, the recent reconstruction of the Neanderthal genome is inspiring some to turn to the ancient genes that guide brain growth, instead, as a way to differentiate between H. neanderthalensis and H. sapiens thinking.
"In 2021, for instance, a team of geneticists investigated a gene called NOVA1, which directs the development of brain tissues in H. neanderthalensis and H. sapiens. Inserting two distinct forms of the gene into clusters of uncultured cells, the team discovered that the form of NOVA1 found in H. neanderthalensis created bumpier blobs of brain tissue when cultured, while the form of NOVA1 found in H. sapiens created smooth, spherical clumps.
"The following year, in 2022, a second team of geneticists followed a similar approach with a gene called TKTL1, which prompts neuron production. While the H. neanderthalensis form of TKTL1 fostered some neurons, the H. sapiens form fostered many more.
"Though these findings do demonstrate that the brains of H. neanderthalensis and H. sapiens developed differently, they don’t disclose all the details of this difference. Individual genes are only tiny threads in a greater genetic tapestry, specialists say, suggesting that a true appreciation of the influence of NOVA1 and TKTL1 on something as complex as cognition can only come in the context of a more complete genome."
Comment: not brutes, much like us, but phenotypically different
Human evolution; stone tools purposeful or accidental
by David Turell , Saturday, March 11, 2023, 20:12 (621 days ago) @ David Turell
Monkeys make stone tools by accident which raises questions about so-called human stone tools:
https://www.newscientist.com/article/2363882-stone-flakes-made-by-monkeys-cast-doubt-on...
"By using stones to break open nuts, monkeys accidentally create sharp-edged flakes that look like the tools believed to have been used by our ancient human relatives.
"The finding casts doubt on whether all the stone flakes found in archaeological digs really are the tools of early hominins — and raises the possibility that they might be accidental by-products of hitting things with whole stones, says Lydia Luncz at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
"In 2016, Luncz and her colleagues realised that Brazilian capuchins produce stone flakes from the rocks they use to pound food, dig and engage in sexual displays, without necessarily meaning to. The flakes were essentially identical to those found in hominin settlements dating to at least 3 million years ago. It made the team wonder whether the artefacts really reflected any technical planning by those early humans.
***
"The team set up motion-activated cameras to study the behaviour of the wild macaques. During 100 hours of footage, the team witnessed monkeys accidentally creating flakes as they struck nuts between two stones – serving as a hammerstone and an anvil – and then leaving the broken stones to find new, whole stones.
"This is almost exactly what the capuchins did in the earlier study, says Luncz, showing that the flake-making wasn’t a one-off. “This was occurring on the other side of the planet, in a different ecosystem and a different species,” she says. “So it was just so obvious that this is a primate thing. This is a foraging behaviour that we assume also happened in early hominins.
***
"The team then compared 1119 stone flakes from the macaques’ nut-cracking sites with artefacts found at hominin sites in Ethiopia, Kenya and Tanzania. The monkeys’ thin, flat, wide stone flakes – ranging from 1.3 to 7.9 centimetres in length – were “almost indistinguishable” from flakes that were associated with ancient humans up to 3.3 million years ago, says Tomos Proffitt, another member of the research team at the Max Planck Institute for Evolutionary Anthropology.
"While there were a few different trends – the monkeys’ flakes were, on average, smaller and thicker than the hominin flakes, for example – they were nonetheless so similar that they could have replaced up to 70 per cent of the ancient humans’ tools.
"The findings could challenge the current understanding of early stone technology, says Proffitt. “I wouldn’t go so far as to say that all of the old material is not intentional,” he says. “But what our study shows is that we can’t be 100 per cent certain that every single flake in the early Stone Age archaeological record was intentionally made. There may be a component within that record that’s unintentional.”
"For Zeray Amelseged at the University of Chicago, the study mostly illustrates the gradual progression of cognitive evolution in primates. “Is what we find in the archaeological record just a result of process without intentionality?” he says. “I don’t think we have an answer, but an important point in this paper is that the actions of stone tool-making and stone tool use have a much deeper history in time as well as in the primate world. And that’s what’s becoming clearer.'”
Comment: Hammering stone on stone will produce somewhat sharp flakes, especially flint. Despite the confusion with ancient stone tools and possible monkey production, humans did understand how to use them in butchering, making hides useful by scraping them, as some of the cognitive evidence.
Human evolution; significance of HAR's
by David Turell , Wednesday, May 10, 2023, 19:22 (561 days ago) @ David Turell
Rapidly changing areas of DNA in humans only:
https://www.sciencealert.com/a-chance-event-1-million-years-ago-changed-human-brains-fo...
"Like treasured recipes passed down from generation to generation, there are just some regions of DNA that evolution doesn't dare tweak. Mammals far and wide share a variety of such encoded sequences, for example, which have remained untouched for millions of years.
"Humans are a strange exception to this club. For some reason, recipes long preserved by our ancient ancestors were suddenly 'spiced up' within a short evolutionary period of time.
"Because we're the only species in which these regions have been rewritten so rapidly, they are called 'human accelerated regions' (or HARs). What's more, scientists think at least some HARs could be behind many of the qualities that set humans apart from their close relatives, like chimpanzees and bonobos.
"Led by computational biologist Katie Pollard, director of the Gladstone Institute of Data Science and Biotechnology in the US, a team of researchers identified HARs nearly two decades ago while comparing human and chimpanzee genomes.
"In a new study, Pollard's team found the 3D folding of human DNA in the nucleus is a key factor in this pivotal moment for our species.
***
a big difference between human and chimpanzee DNA is structural: large chunks of the DNA's building blocks have been inserted, deleted, or rearranged in the human genome. So human DNA folds differently in the nucleus compared with the DNA of other primates.
"Pollard's team investigated whether these structural changes in human DNA, and its altered 3D folding, could have led to particular genes within HARs being 'hijacked', linking them to different protein-coding genes than they were originally applied to.
"Many genes within HARs are linked to other genes, acting as enhancers (meaning they increase transcription of their linked gene/s).
"Enhancers can impact the activity of any gene that ends up close by, which can vary depending on how DNA is folded," Pollard said.
"In a study published earlier this year, Pollard's team created a model suggesting the rapid variations appearing in HARs in early humans often opposed each other, turning the activity of an enhancer up and down in a kind of genetic fine-tuning – a model supported by their new research.
"For their most recent study, the team compared the genomes of 241 mammal species using machine learning to cope with a large amount of data.
"They identified 312 HARs and examined where they are located within the 3D 'neighborhoods' of folded DNA. Almost 30 percent of HARs were in the regions of DNA where structural variations had caused the genome to fold differently in humans compared to other primates.
"The team also discovered neighborhoods containing HARs were rich with the genes that differentiate humans from our closest relatives, chimpanzees.
"In an experiment that compared DNA within growing human and chimpanzee stem cells, one-third of identified HARs were transcribed specifically during the development of the human neocortex.
"Many HARs play a role in embryo development, especially in forming neural pathways associated with intelligence, reading, social skills, memory, attention and focus – traits we know are distinctly different in humans than other animals.
"In HARs, these enhancer genes, unchanged for millions of years, may have had to adapt to their different target genes and regulatory domains.
"Imagine you're an enhancer controlling blood hormone levels, and then the DNA folds in a new way and suddenly, you're sitting next to a neurotransmitter gene and need to regulate chemical levels in the brain instead of in the blood," Pollard said.
""Something big happens like this massive change in genome folding, and our cells have to quickly fix it to avoid an evolutionary disadvantage."
"We don't yet understand exactly how these changes have impacted specific aspects of our brain development, and how they became an integral part of our species' DNA. Though Pollard and her team are already planning to delve into these questions."
"But their research so far does show just how unique – and unlikely – the evolution of the human brain really is." (my bold)
Note the bold. It is Adler all over again!!!! Evolution has a natural pace of DNA developments. Why are humans suddenly the beneficiaries of rapid development? From trees to ground. There is no natural reason we can see. So, God in action!!??
Human evolution; living preferences, open or forest
by David Turell , Thursday, May 11, 2023, 19:33 (560 days ago) @ David Turell
An amazing study:
https://phys.org/news/2023-05-human-ancestors-mosaic-landscapes-high.html
"A new study published in the journal Science by an international team finds that early human species adapted to mosaic landscapes and diverse food resources, which would have increased our ancestor's resilience to past shifts in climate.
***
"To test these fundamental hypotheses on human evolution and adaptation quantitively, the research team used a compilation of more than three thousand well-dated human fossil specimens and archaeological sites, representing six different human species, in combination with realistic climate and vegetation model simulations, covering the past 3 million years. The scientists focused their analysis on biomes—geographic regions which are characterized by similar climates, plants, and animal communities (e.g., savannah, rainforest, or tundra).
***
"According to their analysis, the scientists found that earlier African groups preferred to live in open environments, such as grassland and dry shrubland. Migrating into Eurasia around 1.8 million years ago, hominins, such as H. erectus and later H. heidelbergensis and H. neanderthalensis developed higher tolerances to other biomes over time, including temperate and boreal forests.
"'To survive as forest-dwellers, these groups developed more advanced stone tools and likely also social skills," said Prof. Pasquale Raia, from the Università di Napoli Federico II, Italy, co-author of the study. Eventually, H. sapiens emerged around 200,000 years ago in Africa, quickly becoming the master of all trades. Mobile, flexible, and competitive, our direct ancestors, unlike any other species before, survived in harsh environments such as deserts and tundra. (my bold)
"When further looking into the preferred landscape characteristics, the scientists found a significant clustering of early human occupation sites in regions with increased biome diversity. "What that means is that our human ancestors had a liking for mosaic landscapes, with a great variety of plant and animal resources in close proximity," said Prof. Axel Timmermann, co-author of the study and Director of the IBS Center for Climate Physics in South Korea. The results indicate that ecosystem diversity played a key role in human evolution.
"The authors demonstrated this preference for mosaic landscapes for the first time on continental scales and propose a new Diversity Selection Hypothesis: Homo species, and H. sapiens, in particular, were uniquely equipped to exploit heterogeneous biomes.
"'Our analysis shows the crucial importance of landscape and plant diversity as a selective element for humans and as a potential driver for socio-cultural developments," adds Elke Zeller. Elucidating how vegetation shifts have shaped human sustenance, the new Science study provides an unprecedented view into human prehistory and survival strategies."
Comment: note my bold. Sapiens were super adopters and basically swarmed all over the Eastern hemisphere. Against all odds as measured by Darwin theory was Adler's point.
Human evolution; living preferences, open or forest
by David Turell , Friday, May 12, 2023, 18:29 (559 days ago) @ David Turell
Here is the article that is the basis of the report yesterday:
https://www.sciencemagazinedigital.org/sciencemagazine/library/item/12_may_2023/4100904...
"Taken together, our findings suggest that human species were actively seeking out more abundant and diverse food resources in regions with higher ecosystem diversity . Using a relationship between densities of historical hunter-gatherer populations and our calculated preindustrial biome diversity as a proxy for the past, we propose that diverse landscapes may have also sustained larger hominin populations, serving as hotspots for cultural innovation and playing an important role in genetic diversification.
"The derived inclination of humans toward landscape mosaics and their ability to adapt to regionally diverse vegetation conditions has not been shown before at continental scales, leading us to propose the diversity selection hypothesis: Homo species, and H. sapiens in particular, were specially equipped to exploit heterogeneous habitat conditions. Such heterogeneity, which correlates to high plant and vertebrate richness in current ecosystems, may have conferred hominin resilience to environmental perturbations by providing a wider and more stable resource base. Here we suggest that behavioral and cultural plasticity may have allowed humans to exploit habitat diversity and diverse food resources.
***
"Our data-based diversity selection hypothesis may also add context to our more recent human history. According to our analysis, our genus Homo has adapted over the Pleistocene and migrated to areas with higher landscape diversity. Utilizing resources from various biomes provided a resilient and successful strategy over hundreds of millennia. However, during the Anthropocene, our species has caused a massive decline in global ecosystem diversity due to land use practices, gradually shifting away from integrated agricultural practices and toward monocultures. Modern humans have clearly taken an unprecedented path away from our ancestors’ resilience and diversity-based strategies."
Comment: no question H. erectus leading to H. sapiens was the final step. The jump from Lucy-like forms to our present form occurred quickly as compared to most mutation rates calculated in the recent past. Adler's point is still cogent. Why the giant brain, not needed when it appeared. Adler's point is/was God at work to prduce us. Nature itself couldn't do it.
Human evolution;sapiens vs Neanderthal hunting skills
by David Turell , Saturday, May 27, 2023, 01:25 (544 days ago) @ David Turell
Sapiens had bows and arrows, the Neanderthals did not:
https://today.uconn.edu/2023/02/new-study-shows-archery-appeared-in-europe-thousands-of...
"A new study published in Science Advances contextualizes the traditions and technological knowledge of early, pioneering Homo sapiens. The study demonstrates the mastery of archery by modern populations and extends the evidence of archery in Europe back by about 40,000 years.
"The researchers analyzed lithic artifacts from a cave in Mediterranean France called Grotte Mandrin, which reveals the oldest occupation of modern humans on the European continent. The study focuses on a very rich level, attributed to the Neronian culture, and testifies to Homo sapiens occupations dating back 54,000 years, interposed between numerous Neanderthal occupations in the cave before and after the modern humans. That’s roughly 10,000 years earlier than what had been previously believed to be the earliest occupation of modern humans in Europe.
***
"The study also highlights different traditions in weaponry among Neanderthals – theirs were systematically represented by heavy hasted weapons, thrusted spears, or thrown javelins, used by hand – and illustrates a profound technological contrast between Neanderthal populations and the first modern humans arriving on the European continent.
“'When Neanderthals use their traditional weapons, such as a spear thrusted or thrown by hand, the first modern humans came with bow and arrows technologies,” says Metz. “Bows are used in all environments, open or closed, from the desert, and are effective for all prey sizes. Arrows can be shot quickly, with more precision. Many arrows can be carried in a quiver during a hunting foray. These technologies then allowed an incomparable efficiency in all hunting activities when Neanderthals had to hunt in close or direct contact with their prey, a process that may have been much more complex, more hazardous, and even much more dangerous when hunting large game like bison.”
"The emergence in prehistory of mechanically propelled weapons, such as spear throwers and the bow-and-arrow, is commonly perceived as one of the hallmarks of the advance of modern human populations into the European continent. However, the existence of archery has always been difficult to trace.
***
"Based on the analysis of these stone armatures, the recognition of archery is now well documented in Africa, dating back some 70,000 years. Some flint or deer antler armatures suggest the existence of archery from the early phases of the Upper Paleolithic in Europe more than 35,000 years ago, but the morphology and the hafting modes of these ancient armatures do not allow them to be linked to a distinct mode of propulsion, making the possible existence of archery during the European Paleolithic nearly invisible.
***
"This study also sheds light on the weaponry of Neanderthal populations, showing that, as contemporaries of Neronian modern humans, Neanderthals did not develop mechanically propelled weapons like technologies using bows or thrusters, and continued to use their traditional weapons based on the use of massive spear-shaped points that were thrusted or thrown by hand, requiring close contact with their game.
"The traditions and technologies mastered by these two populations were therefore profoundly distinct, illustrating a remarkable objective technological advantage for modern human populations during their expansion into the European continent.
***
“'Research is ongoing in Grotte Mandrin, and the last field season revealed that the site was far larger than expected and should cover an impressive surface of more than 1,000 square meters, with high density of archeological material even far from the entrance of the cave,” says Metz. “Grotte Mandrin has already totally reshaped our understanding of the last Neanderthals and the first migrations of Sapiens in continental Europe, deeply changing the way we understand this major event in the human history that saw the extinction of our last cousins, leaving for the first time the planet with only 1 hominin species.'”
Comment: propulsive weaponry is a more conceptually elegant form of a fighting or hunting technique. Perhaps we simply outthought them.
Human evolution; earliest sapiens footprints
by David Turell , Tuesday, May 30, 2023, 22:03 (541 days ago) @ David Turell
In South Africa 153,000 years ago:
https://www.livescience.com/archaeology/153000-year-old-footprints-from-south-africa-ar...
"The record-breaking finding is one of many unearthed in Africa over the past few decades. Since the report of 3.66 million-year-old footprints at the site of Laetoli in Tanzania over 40 years ago, paleoanthropologists have found more than 100 walking trails preserved in rocks, ash and mud left by our hominin ancestors, the group that includes modern and extinct humans as well as our closely-related ancestors.
"Seven archaeological sites with tracks left by humans — called “ichnosites” — were discovered just east of the southern tip of the African continent, tens of miles inland from the ancient coast. In an article published April 25 in the journal Ichnos, an international team of researchers used optically-stimulated luminescence (OSL) to figure out when the impressions were made.
***
"These South African ichnosites included four with hominin tracks, one with knee impressions, and four with “ammoglyphs” — a term denoting any pattern, not just footprints, made by humans that has been preserved over time.
"Footprint evidence can add a great deal to the archaeological record, according to the researchers, as it "can provide not just an indication of humans travelling across these surfaces as individuals or groups, but also evidence of some of the activities that they engaged in," the authors wrote in the study. In South Africa, early evidence for modern human behavior includes personal adornment such as jewelry, development of intricate stone tools, the use of abstract symbols, harvesting of shellfish, and coastal cave and rock-shelter sites."
Comment: Homo sapiens developed all over Africa making a big enough gene pool to allow a great diversity of development.
Human evolution; Homo Habilis
by David Turell , Friday, June 09, 2023, 20:27 (531 days ago) @ David Turell
A very early Homo type:
https://www.discovermagazine.com/the-sciences/what-we-know-about-homo-habilis?utm_sourc...
"If there’s one thing that paleoanthropology has revealed time and again, it’s that many renditions of ancient human species preceded us modern humans today.
"While Neanderthals and even Homo erectus have become fixtures in the human origin story, a lesser-known predecessor appears to predate all the others: Homo habilis.
"H. habilis has been called the oldest known member within the Homo genus, though not without controversy and ongoing debate.
"By many scientists’ accounts, the species was likely walking upright on Earth more than 2 million years ago — which is to say, nearly 2 million years before Homo sapiens even appeared on the evolutionary tree.
"The Latin name for this species, loosely translated as “handy man” or “able man,” alludes to a crucial characteristic that set it apart: dexterous hands.
"Fossilized specimens have included human-like foot and hand bones, which suggests an ability to manipulate objects with precision. And, in fact, simple stone tools have been found near some of the earliest H. habilis remains identified by anthropologists.
"An enlarged brain case also distinguishes this species from our more distant, early hominid ancestor Australopithecus — famously known for the 3-million-year-old Lucy specimen in Ethiopia.
"H. habilis made its debut in the conversation of human origins in the early 1960s, after a series of landmark discoveries by anthropologists Louis S.B. Leakey and Mary Leakey, who were married.
***
"After combining and assessing their various specimens, they presented a picture that seemed to mix human-like features with characteristics also seen in the ape-like Australopithecus.
"Louis S.B. Leakey, alongside co-authors Phillip Tobias and John Napier, published the first paper on H. habilis in Nature in 1964.
"That work addressed three key elements to meet the definition of Homo. They argued that their specimen had a bipedal gait, an upright posture and the ability to fashion simple stone tools.
***
"Subsequent discoveries have indicated that H. habilis likely had an average braincase capacity around 640 cubic centimeters (CC), compared to 440 CC in Australopithecus. (The equivalent in H. sapiens averages just over 1,300 CC.)
"Other features seen in H. habilis specimens, including a relatively large facial skeleton with a flattened lower part and particularly long limbs, make it seem like an intermediate species between Australopithecus and H. erectus — though it may not be in direct succession.
"Likely remains of the mysterious species have also now been found in northern Kenya, Ethiopia and South Africa.
***
"Notably, the world’s oldest known stone tools now appear more than 3 million years ago in the fossil record, which seems to be well before H. habilis. And scientists still aren’t sure what species created these tools.
"If it was not Australopithecus, perhaps there is another handy predecessor to H. habilis waiting to be unearthed."
Comment: an early part of a still very incomplete record.
Human evolution; influence of Neanderthal genes
by David Turell , Saturday, June 10, 2023, 21:31 (530 days ago) @ David Turell
In immunity and calorie burn:
https://www.sciencedaily.com/releases/2023/06/230608195656.htm
"Recent scientific discoveries have shown that Neanderthal genes comprise some 1 to 4% of the genome of present-day humans whose ancestors migrated out of Africa, but the question remained open on how much those genes are still actively influencing human traits -- until now.
***
"the researchers reported that some Neanderthal genes are responsible for certain traits in modern humans, including several with a significant influence on the immune system. Overall, however, the study shows that modern human genes are winning out over successive generations.
"'Interestingly, we found that several of the identified genes involved in modern human immune, metabolic and developmental systems might have influenced human evolution after the ancestors' migration out of Africa," said study co-lead author April (Xinzhu) Wei, an assistant professor of computational biology
***
"Using a vast dataset from the UK Biobank consisting of genetic and trait information of nearly 300,000 Brits of non-African ancestry, the researchers analyzed more than 235,000 genetic variants likely to have originated from Neanderthals. They found that 4,303 of those differences in DNA are playing a substantial role in modern humans and influencing 47 distinct genetic traits, such as how fast someone can burn calories or a person's natural immune resistance to certain diseases.
"Unlike previous studies that could not fully exclude genes from modern human variants, the new study leveraged more precise statistical methods to focus on the variants attributable to Neanderthal genes."
Comment: these results are generalizations about genetic influences. Were these trysts consensual? I doubt it. Humans and Neanderthals coexisted side by side, but there is no evidence of cooperation.
Human evolution: recoil in our foot
by David Turell , Sunday, June 11, 2023, 17:37 (529 days ago) @ David Turell
Helps upright posture and running:
https://www.discovermagazine.com/health/the-surprising-truth-about-the-skip-in-your-ste...
"The skip in the human footstep – the flexing of the arch with each step – does little to help carry the body forward, a new study has found. Instead, it serves to keep the ankle upright, so that we walk in the characteristic way of human beings and not like other apes.
"The finding overturns conventional wisdom and may help in the treatment of people whose arches have become rigid due to illness or injury.
“'We thought originally that the spring-like arch helped to lift the body into the next step,” says Lauren Welte, a researcher at UW-Madison and the first author of the study, in a press release. But the project found that “the spring-like arch recoils to help the ankle lift the body,” she says.
"The subtle flexing acts as a linchpin for humans to remain upright, the team from Canada, the United States, Sweden and Australia found. In particular, the study points to one of the most underappreciated joints in the human body, the union between the navicular and medial cuneiform, which is crucial to the recoil. Without it, humans would walk more like chimpanzees, our close genetic relatives.
"In such a scenario, our ankles would angle forward as we walked and not remain relatively upright, as they do now. We’d lose the efficiency of the latter, especially when running, which might be how we evolved arch recoil in the first place. The usefulness of it while hoofing away from predators (or toward food) may have driven natural selection, the researchers say.
“'The mobility of our feet seems to allow us to walk and run upright instead of either crouching forward or pushing off into the next step too soon,” says Michael Rainbow, an assistant professor at Queen’s University, in a press release.
"The study scanned the feet of seven young men and women, with high-speed X-ray photography, as they walked and ran, to watch the complex interplay of bones and connective tissue. The team saw that the recoil allowed the foot to remain in contact with the floor longer and better propel the body forward.
"In another phase of the project, the researchers used a computer model to simulate a foot with no flex and found that its style of walking would have consumed more energy."
Comment: a great foot design. The authors invoke Darwin by blaming natural selection.
Human evolution: humans reach Asia
by David Turell , Tuesday, June 13, 2023, 18:39 (527 days ago) @ David Turell
A new finding in am cave in Laos:
https://www.newscientist.com/article/2378160-fossils-in-laos-cave-imply-modern-humans-w...
"Fossils from a Laos cave provide the earliest evidence of modern humans in mainland South-East Asia. Uncovered fragments of bone belonging to Homo sapiens may date back 86,000 years, shedding new light on how our species migrated from Africa to Asia.
"Since 2009, several modern human fossils – dating to between 46,000 and 70,000 years ago – have been discovered in Tam Pà Ling, a cave in north-east Laos. Now, Fabrice Demeter at the University of Copenhagen, Denmark, and his colleagues have added two more fossils to the collection.
“'One of my Laos colleagues saw what we thought was a big piece of stone,” says Demeter. “After we removed it, I realised that it was white. I [then] knew it was a piece of bone.” Upon analysis, the fossil turned out to be small fragment of a human skull. The researchers also unearthed a piece of a human tibia, or shinbone.
"Using radioactive isotopes to date the sediment surrounding the fossils in the cave, the team estimates they are between 68,000 and 86,000 years old. “In mainland South-East Asia, this is the first time we’ve got such old specimens,” says Demeter.
"The findings suggest that early modern humans travelled to South-East Asia earlier than previously thought. Prior estimates put this at around 50,000 years ago, with these humans migrating out of Africa and beginning to populate the rest of the world, including Asia. Most people alive today are descended from these early humans, aside from Indigenous Australians, whose ancestors may have left Africa even earlier than this.
***
"Genetic data suggests that most earlier migrations probably failed, she says. The fossils discovered in Tam Pà Ling could belong to the ancestors of Indigenous Australians, whose remains found in Australia date back much earlier than 50,000 years ago, but with little information about where they came from. More research is needed into this, says Demeter.
“'One of the most debated topics in palaeoanthropology today continues to be modern human origins,” says Christopher J. Bae at the University of Hawai’i at Manoa. “This particular study shows quite clearly that modern humans were in the region earlier than originally supposed.'”
Comment: a human characteristic is curiosity. The migrations are looking for a friendlier neighborhood, a need to move away if things are too crowded, and curiosity about what is over the next hill. Interestingly it took until about 26,000 years ago to reach the Americas.
Human evolution: new discoveries in footprints
by David Turell , Wednesday, June 14, 2023, 00:06 (527 days ago) @ David Turell
A new review of the discoveries of sapiens footprints:
https://phys.org/news/2023-06-oldest-homo-sapiens-footprint-years.html
"In 2023 the situation is very different. It appears that people were not looking hard enough or were not looking in the right places. Today the African tally for dated hominin ichnosites (a term that includes both tracks and other traces) older than 50,000 years stands at 14. These can conveniently be divided into an East African cluster (five sites) and a South African cluster from the Cape coast (nine sites). There are a further ten sites elsewhere in the world including the UK and the Arabian Peninsula.
"Given that relatively few skeletal hominin remains have been found on the Cape coast, the traces left by our human ancestors as they moved about ancient landscapes are a useful way to complement and enhance our understanding of ancient hominins in Africa.
***
"We found that the sites ranged in age; the most recent dates back about 71,000 years. The oldest, which dates back 153,000 years, is one of the more remarkable finds recorded in this study: it is the oldest footprint thus far attributed to our species, Homo sapiens.
"The new dates corroborate the archaeological record. Along with other evidence from the area and time period, including the development of sophisticated stone tools, art, jewelry and harvesting of shellfish, it confirms that the Cape south coast was an area in which early anatomically modern humans survived, evolved and thrived, before spreading out of Africa to other continents.
"There are significant differences between the East African and South African tracksite clusters. The East African sites are much older: Laetoli, the oldest, is 3.66 million years old and the youngest is 0.7 million years old. The tracks were not made by Homo sapiens, but by earlier species such as australopithecines, Homo heidelbergensis and Homo erectus. For the most part, the surfaces on which the East African tracks occur have had to be laboriously and meticulously excavated and exposed.
***
"A key challenge when studying the palaeo-record—trackways, fossils, or any other kind of ancient sediment—is determining how old the materials are.
"Without this it is difficult to evaluate the wider significance of a find, or to interpret the climatic changes that create the geological record. In the case of the Cape south coast aeolianites, the dating method of choice is often optically stimulated luminescence.
"This method of dating shows how long ago a grain of sand was exposed to sunlight; in other words, how long that section of sediment has been buried. Given how the tracks in this study were formed—impressions made on wet sand, followed by burial with new blowing sand—it is a good method as we can be reasonably confident that the dating "clock" started at about the same time the trackway was created.
***
"The overall date range of our findings for the hominin ichnosites—about 153,000 to 71,000 years in age—is consistent with ages in previously reported studies from similar geological deposits in the region.
"The 153,000 year old track was found in the Garden Route National Park, west of the coastal town of Knysna on the Cape south coast. The two previously dated South African sites, Nahoon and Langebaan, have yielded ages of about 124,000 years and 117,000 years respectively.
***
"A decade from now, we expect the list of ancient hominin ichnosites to be a lot longer than it is at present—and that scientists will be able to learn a great deal more about our ancient ancestors and the landscapes they occupied."
Comment: a continuing support for the theory sapiens developed all over Africa. See the entry on HAR's, rapidly evolving areas of human DNA.
Human evolution: Paranthropus robustus distant cousin
by David Turell , Friday, July 14, 2023, 16:04 (496 days ago) @ David Turell
Careful genetic study:
https://www.sciencealert.com/ancient-outsider-human-species-pinpointed-in-oldest-geneti...
"Researchers have managed the incredible feat of predicting genetic relationships between some of the earliest hominins to live on planet Earth, using little more than some proteins scraped from 2 million year old fossilized teeth.
"The team behind the new study, mostly from the University of Copenhagen in Denmark and the University of Cape Town in South Africa, says the analysis will be vitally useful in tracing the distant family tree of human beings.
"'The evolutionary relationships among extinct African hominin taxa are highly debated and largely unresolved, due in part to a lack of molecular data," write the researchers.
***
"When it comes to timescales of thousands and millions of years, answering those questions isn't at all straightforward. The DNA molecule is fragile, prone to disintegrating quickly. Nuclear DNA from 430,000 year old hominin remains of has been deciphered, yet the process itself was far from productive.
"Proteins can be a little more robust, and their amino acide sequences can be translated back into a possible genetic code that produced them. Although far from precise, it could serve as a reasonable proxy for estimating a genetic relationship where the genes themselves can't be read.
"In this case the data was interpreted enamel on teeth recovered from Swartkrans cave, an important site for archaeological material that's about 40 kilometers (25 miles) to the northwest of Johannesburg. They were thought to belong to an ancient relative of ours, Paranthropus robustus.
"By cross-checking their results against DNA information from other fossils and today's hominids – from orangutans to humans – the researchers were able to tentatively show that P. robustus represented an "outgroup" (like distant cousins, in a way) to the evolutionary line that includes Homo sapiens, Neanderthals, and Denisovans.
"Flash floods in an otherwise arid area were responsible for these teeth being so well buried and preserved, the team reports. That may limit how many other fossils we can find like this, but the techniques used here should be able to be applied elsewhere too.
"'This study demonstrates the feasibility of recovering informative Early Pleistocene hominin enamel proteins from Africa," write the researchers."
Comment: the hominin branching is quite broad, and this new technique will help sort it out. Of course dhw will comment, this shows how God experimented with early human forms, indicating to me His form of God struggled to invent H sapiens.
Human evolution: genetic source of upright posture
by David Turell , Friday, July 21, 2023, 23:18 (489 days ago) @ David Turell
edited by David Turell, Friday, July 21, 2023, 23:26
Latest massive study:
https://www.nature.com/articles/d41586-023-02345-7?utm_source=Nature+Briefing&utm_c...
"Humans are the only great apes to routinely walk on two legs, a posture that relies on us having long legs, short arms and narrow hips. A study, published this week in Science, has generated a map of genomic regions that could explain how our unique skeletal architecture evolved. The work also points to regions of our DNA that place us at risk of the common skeletal disease osteoarthritis.
***
"Narasimhan and his colleagues turned to the UK Biobank, a repository of genetic and health data for half a million people, to obtain records that included whole-body X-ray images. They used artificial intelligence (AI) to weed out images that couldn’t be used in the analysis, such as blurred pictures and those of people with implants or amputations. They then applied further rounds of AI analyses to extract precise measurements of bone lengths from more than 31,000 records.
"Visscher says that the paper is “a real tour de force and clever use of computational deep-learning methodology”.
"The genome-wide map that Narasimhan and his colleagues generated identified 145 genetic locations associated with changes to skeletal proportions. Many of the identified regions are known to have roles in skeletal development and 45 of the locations overlapped a single protein-coding gene. Of those, 32 have previously been identified as resulting in abnormal skeletons when disrupted in mice, and 4 as causing rare skeletal diseases in humans.
"The team investigated a range of skeletal ratios, such as hip width to shoulder width, forearm length to height, and torso length to leg length. Limb and torso proportions were linked to distinct regions of the genome, suggesting that their development is controlled by separate genetic programs.
"Having longer legs than arms is a hallmark of walking upright, and genomic regions linked to changes in this ratio were different to similar regions in other great apes, a sign that these regions were under evolutionary selection in humans. The same was true for regions linked to narrow hips relative to overall height.
"One theory for why early hominins evolved upright walking is that their bodies were better able to keep cool in hot environments. Using biobank data on metabolic rate and body mass, the researchers found support for this hypothesis: as leg length increases, heat dissipation to stay cool improves. “There is this correlation between skeletal proportions and metabolic rate and fat-free body mass, which is in line with what the theory would predict,” says Narasimhan.
***
"Bo Xia, a genomics researcher at Harvard University in Cambridge, Massachusetts, says that further work to identify the genetic elements responsible is needed, but will be challenging. Genome-wide association studies are powerful tools for identifying candidates for future research, he says, but pinpointing which genes directly affect the developmental processes is not straightforward if genetic variation occurs outside gene-coding sequences. “A non-coding region mutation near a specific gene doesn’t necessarily indicate that the variant is affecting the gene that’s close to it,” he says."
Comment: A previous paper presented here described HAR's, regions of DNA with accelerated changer toward an evolving sapiens form (Friday, August 14, 2020, 22:11). I wonder if the regions described here are comparable in DNA 3-D geography. The theory about long legs keeping an animal cooler should also be applied to apes and monkeys. If beneficial why didn't their legs lengthen like ours did? Pure Darwinist 'just so' silly thinking to explain away our obvious favorable differences in evolution.
Human evolution: hair loss
by David Turell , Tuesday, August 08, 2023, 17:44 (471 days ago) @ David Turell
edited by David Turell, Tuesday, August 08, 2023, 17:56
Current theory:
https://www.the-scientist.com/ts-digest/issue/the-roles-of-endogenous-psychedelics-18-2...
"Luscious fur coats insulate many animals from the cold and protect them from sunlight, insects, and sharp objects in their environments. Yet, somehow humans evolved to be relatively hairless. While this may appear to be a case of selection against a highly desirable trait, Nina Jablonski, who studies the evolution of human skin and skin pigmentation at Pennsylvania State University, said that our relative hairlessness arose just like other traits did: it offered evolutionary advantages.
"The origins of human hairlessness began nearly two million years ago, driven by environmental changes in locations where human ancestors lived. As wooded landscapes in equatorial Africa gave way to open grassland areas, human ancestors had to spend more time outdoors to find food and water. For walking and running long distances, early members of the genus Homo developed a modern human skeleton with long legs and shorter arms. “Around this time, humans lost most of their body hair,” said Jablonski.
"Shedding body hair was a key adaptation since, unlike most other mammals, primates lack a key mechanism for cooling the blood around the brain when it’s hot outside or after exercise. This means that the temperature of the brain increases when the body heats up, which can affect brain functions. Evolution of human hairlessness was accompanied by the development of more sweat glands and darker skin pigmentation. Sweat glands helped them dissipate heat from the skin more effectively, while darker skin pigmentation protected their mostly hairless skin from the damaging effects of solar radiation.
"According to Jablonski, the idea of whole body cooling and heating, or thermoregulation, seems like the most likely explanation for human hairlessness based on physical evidence and our knowledge of comparative anatomy and physiology. “We were shooting in the dark decades ago. Now, we can be much, much clearer on what the likely courses of evolution were,” she said."
Comment: this is an educated guess, since fossilized bones are not hairy. Furred animals don't sweat. Note the complex physiological changes for sweating to maintain heat loss from exercise. Sweat is a saltwater substance, so it helps in sodium balance. It also removes urea and ammonia. The circulation to the skin increases which helps in heat loss from simple radiation to the air. Ape to sapiens was not a simple transition.
Human evolution: erectus tool shop
by David Turell , Thursday, August 10, 2023, 15:20 (469 days ago) @ David Turell
In Israel:
https://www.discovermagazine.com/the-sciences/ancient-humans-made-expeditions-to-this-7...
"Our understanding of our ancestors gets pretty murky when you go far enough back in time. Still, scientists have discovered numerous tools associated with Homo erectus — widely regarded as a direct ancestor to modern humans — over the years. For example, researchers recently discovered tools in Kenya (associated possibly with Paranthropus or another precursor to the Homo genus) that may date back as far as 3 million years.
"But there's a difference between making a few tools when the opportunity arises and having an actual workshop you can use and pass down to your descendants.And as scientists have been learning, our ancestors were capable of both, showing that they were making plans rather than just reacting to their immediate environment.
"Indeed, researchers have now confirmed one of the earliest known workshops of the human genus at a flint rock exposure in northern Israel — a place that individuals likely used for tens of thousands of years.
“'They probably transferred this knowledge through many generations,” says Meir Finkel, a geoarchaeologist at Tel Aviv University in Israel and coauthor on the recent study.
"Gesher Benot Ya’aqov (GBY) is a famous archaeological site in the Hula Valley in northern Israel. The site holds the remains of a number of large animals like elephants, as well as the stone tools used to butcher them. After being drained in the 1950s, the now-dry area was once a lake where large animals would come to drink.
"Researchers still aren’t sure whether the hominids who lived at the site hunted elephants and other animals, or used the mud as a kind of trap where they could opportunistically kill creatures that became stuck, Finkel says. Either way, the hominids at GBY and nearby Ma’ayan Barukh, also in the Hula Valley, had a reliable food resource they returned to again and again for hundreds of thousands of years.
"Thousands of hand axes and other tools have been discovered at both sites, which belong to the Acheulian style, a type of usually oval stone tool industry often associated with Homo erectus that lasted from roughly 1.7 million years ago to about 200,000 years ago. The GBY site dates to roughly 750,000 years ago, while Ma’ayan Barukh dates to about 500,000 years ago.
***
"Most of the flint exposures at these sites weren’t large enough to produce the quantity of stone tools found at the Hula Valley sites. What's more, making Acheulian hand axes isn’t very efficient; Finkel says that the production of each hand axe meant about 75-80 percent waste on average. Nothing except for the flint outcropping at Dishon would have supplied enough stone for more than a few tools.
"But just to be sure, the team analyzed samples from all of these places with the mass spectrometer. The signatures of the 20 flint tools from GBY and Ma’ayan Barukh matched the stone at Dishon Plateau — showing almost definitively they all came from the same place.
“There is practically no other option for that amount of hand axes anywhere else,” Finkel says.
"Going to the Dishon Plateau, which is about 20 kilometers to the west of the Hula Valley and would have required climbing about 800 meters in elevation, likely required planning on the part of the people using tools. “It’s not on the way to anywhere, they have to go specifically to this place,” Finkel says.
***
"The evidence in the Hula Valley and Gishon Plateau “may be the first proof of what is seen in ethnographic research,” he says. Whether Acheulian foragers waited to hunt elephants with these axes and other weapons, or just waited by the ancient Hula Lake for trapped animals, they had to be ready to strike when the time was right.
“'Going to get hand axes was great planning,” Finkel adds."
Comment: the brains then planned and produced weapons in advance of need. Over a century ago Henry Ford invented the production line for automobiles. Like the erectus brain which lasted hundreds of thousands of years, the sapiens brain used for 315,000 years building concepts one upon each other with constant learning, yet dhw doesn't see the brains were planned for future use.
Human evolution: new cave art found
by David Turell , Friday, September 15, 2023, 01:13 (433 days ago) @ David Turell
See the photos to appreciate:
https://www.smithsonianmag.com/smart-news/archaeologists-discover-more-than-100-ancient...
"Two years ago, when a team of archaeologists spotted a painting of an extinct wild bull called an auroch on the wall of a cave in Spain’s Cova Dones, located in Millares, near Valencia, they knew it was important. While Spain has the largest number of Paleolithic cave art sites, most are concentrated in the country’s northern region, while few have been documented in Eastern Iberia.
"However, they didn’t realize just how significant the newly discovered cave art was until they returned to fully document it.
***
“'The cave is arguably the ‘most important’ Paleolithic rock art site ever discovered on the eastern coast of the Iberian Peninsula, the researchers said,” Newsweek’s Aristos Georgiou writes. The researchers believe it is the Paleolithic cave with the greatest number of motifs discovered in Europe since 2015.
"One of the most notable parts of this new discovery is the way the drawings were created. While some are etched and others shaded with white mondmilch, a type of limestone precipitate, the majority are clay-based. “Red clay found on the cave floors was the medium of choice for the Cova Dones occupants—rather than the diluted ochre or manganese typically used in other places throughout the region,” writes Matthew Ward Agius of Cosmos. “Clay-based painting is a rarely-used technique in Palaeolithic art.
"Indeed, the rare technique initially proved difficult to spot, as the red clay had been partially covered by calcite over time, reports Hyperallergic’s Elaine Velie.
“'Animals and signs were depicted simply by dragging the fingers and palms covered with clay on the walls,” Ruiz-Redondo says in a statement. “The humid environment of the cave did the rest: the ‘paintings’ dried quite slowly, preventing parts of the clay from falling down rapidly, while other parts were covered by calcite layers, which preserved them until today.'”
Comment: Very aesthetic art to me. In proper porportions.
Human evolution: Neanderthal fire use
by David Turell , Sunday, October 22, 2023, 15:31 (396 days ago) @ David Turell
Very much like sapiens:
https://www.sciencealert.com/neanderthals-might-not-be-the-separate-species-we-always-t...
"In spite of the myriad of findings detailing their genetic and cultural similarities, our long-extinct 'cousins' are still all too often exiled into their own species, Homo neanderthalensis.
"That categorization is due for a change, according to a team of researchers who have spent the past twenty years digging through layers of dust and grit in the central Portuguese cave site of Gruta da Oliveira.
"'More than different species, I would speak of different human forms," says University of Trento archaeologist Diego Angelucci, the lead author of a recent study summarizing decades of research on what was home to families of Neanderthal more than 71,000 years ago.
"Angelucci and his team detailed the occupation of Gruta da Oliveira, which saw Neanderthals intermittently share time in the cave with wolves, lions, brown bears and lynxes between 93,000 and 71,000 years ago.
"Among the scattering of stone tools and animal remains were bones that had been burned in a way that provided strong evidence of controlled use of fire.
"Cooking a range of meats, including goat, deer, and horses on a hearth that rarely moved out of position, it was clear fire was a central part of everyday Neanderthal life at Gruta da Oliveira.
"It's no secret that branches of the hominin family tree have appreciated a good blaze for at least 250,000 years or so. For a significant proportion of that time, those flames were deliberately lit, well managed, and contained with the purpose of cooking, if not also staying warm and keeping predators at bay.
"Yet Neanderthals had already long diverged from our shared ancestral lineage by the time anatomically modern humans became recognizably distinct, with some speculating they went their own way more than 800,000 years ago.
***
"As discoveries mounted and analytical tools improved, our impressions of the Neanderthal gradually shifted. Gone is the archaic stoop and animalistic grunting. Today our 'primitive' relatives appear to have intentionally buried their dead, made jewelry, and may even have created art.
"Evidence that they carefully used fire in their technology only further builds a case that Neanderthal culture was far from simple, and far more akin to our own.
"'There is a general agreement among archaeologists that they knew how to use fire," says Angelucci.
***
"Just how they might have started fires isn't yet clear, though Angelucci speculates it might not have been all that different to other Neolithic practices, such as the flint and tinder method used by Ötzi, the Iceman.
"With genetic analysis confirming Neanderthals frequently interbred with our own ancestors multiple times through history, the case for them being a separate species weakens only further.
***
"Still, as more sibling than cousin, it seems the poor old Neanderthal deserves to sit right by our side in the Homo sapien family portrait."
Comment: Use of fire is very important along with clothing, burials, cave art, and jewelry. We know nothing about their possible use of language. I still view them as very close cousins.
Human evolution: more about the gut's brain
by David Turell , Wednesday, November 22, 2023, 18:32 (365 days ago) @ David Turell
Glia and neurons with vagus nerve and hypothalamus connections:
https://www.quantamagazine.org/in-the-guts-second-brain-key-agents-of-health-emerge-202...
"Breaking down food requires coordination across dozens of cell types and many tissues — from muscle cells and immune cells to blood and lymphatic vessels. Heading this effort is the gut’s very own network of nerve cells, known as the enteric nervous system, which weaves through the intestinal walls from the esophagus down to the rectum. This network can function nearly independently from the brain; indeed, its complexity has earned it the nickname “the second brain.” And just like the brain, it’s made up of two kinds of nervous system cells: neurons and glia.
***
"Neuroscientists have increasingly discovered that glia play physiological roles in the brain and nervous system that once seemed reserved for neurons.
"A similar glial reckoning is now happening in the gut. A number of studies have pointed to the varied active roles that enteric glia play in digestion, nutrient absorption, blood flow and immune responses. Others reveal the diversity of glial cells that exist in the gut, and how each type may fine-tune the system in previously unknown ways. One recent study, not yet peer-reviewed, has identified a new subset of glial cells that senses food as it moves through the digestive tract, signaling to the gut tissue to contract and move it along its way.
***
" scientists now know that enteric glia are among the first responders to injury or inflammation in gut tissue. They help maintain the gut’s barrier to keep toxins out. They mediate the contractions of the gut that allow food to flow through the digestive tract. Glia regulate stem cells in the gut’s outer layer, and are critical for tissue regeneration. They chat with the microbiome, neurons and immune-system cells, managing and coordinating their functions.
***
"Those methods allowed her to get the “first glimpse into the diversity of these glial cells” across all tissues of the duodenum, Scavuzzo said. In June, in a paper published on the biorxiv.org preprint server that has not yet been peer-reviewed, she reported her team’s discovery of six subtypes of glial cells, including one that they named “hub cells.”
"Hub cells express genes for a mechanosensory channel called PIEZO2 — a membrane protein that can sense force and is typically found in tissues that respond to physical touch. Other researchers recently found PIEZO2 present in some gut neurons; the channel allows neurons to sense food in the intestines and move it along. Scavuzzo hypothesized that glial hub cells can also sense force and instruct other gut cells to contract. She found evidence that these hub cells existed not only in the duodenum, but also in the ileum and colon, which suggests they’re likely regulating motility throughout the digestive tract.
***
"The experiment offered clear evidence that, in addition to other cells, “glial cells can also sense physical forces” through this mechanosensory channel, said Vassilis Pachnis, the head of the nervous system development and homeostasis laboratory at the Francis Crick Institute. Then, having sensed the change in force, they can shift the activity of neural circuits to trigger muscular contractions. “It’s a wonderful piece of work,” he said.
"Hub cells are only one of many glial subtypes that play functional roles in the gut. Scavuzzo’s new six subtypes, added to those characterized in previous research, together reveal 14 known subgroups of glia across the duodenum, ileum and colon. More are likely to be discovered in coming years, each with new potential to better explain how digestion works and enable researchers to develop treatments for a variety of gastrointestinal disorders.
***
"Several years ago, Pachnis and his group found that glia are among the first cell types to respond to injury or inflammation in the mouse gut, and that tampering with enteric glial cells can also create an inflammatory response. In the gut glia seem to perform roles similar to those of true immune cells, Pachnis said, and so their dysfunction can lead to chronic autoimmune disorders and inflammatory bowel diseases, such as ulcerative colitis and Crohn’s disease. “Glial cells definitely play a role in the initiation, the pathogenesis and the progression of the various diseases of the gut,” he said.
"Glia are likely involved because of their central role in communicating between the microbiome, immune cells and other gut cells. Healthy glia strengthen the intestines’ epithelial barrier, a layer of cells that keeps out toxins and pathogens and absorbs nutrients. But in patients with Crohn’s disease, glial cells don’t function properly, resulting in a weaker barrier and inappropriate immune response.
***
"These new studies in enteric glia will go a long way toward explaining many gastrointestinal disorders that researchers have struggled to understand and treat, Sharkey said. “I’m really excited to see how these cells have evolved to become central figures in enteric neurobiology over the years.”
"It’s becoming ever clearer that the neuron doesn’t act alone in the enteric system, he added. “It’s got these beautiful partners in glia that really allow it to do its thing in the most efficient and effective way.'”
Comment: all reporting to the hypothalamus. The gut and its nervous system is irreducibly complex and is designed.
Human evolution: the place of Paranthropus
by David Turell , Thursday, November 23, 2023, 19:23 (364 days ago) @ David Turell
It seems they coexisted with more advanced Homo species:
https://www.newscientist.com/article/mg26034660-800-how-did-paranthropus-the-last-of-th...
"Spurred on by the discovery of more fossils, researchers are finally reassessing this addition to our evolutionary tree – and their work suggests it was one of the oddest. Paranthropus may have been a skilled tool-maker, but it also potentially grazed grass like a cow and communicated with low rumbles like an elephant. The question now is, can the research bring us closer to understanding how the last of the ape-people survived in a world that was dominated by early humans?
***
"But in this grand picture of hominin evolution, Paranthropus sticks out like a sore thumb. Its brain was similar in size to that of the ape-like hominins, and its teeth were exceptionally large. But it lived late in the story – an ape-like hominin alongside the human-like species. “We have evidence of Paranthropus from 2.8 to 1.4 million years ago,” says Kaye Reed at Arizona State University.
***
"In particular, we learned decades ago that it had “this really almost dish-shaped face that is caused by the cheekbones getting so big to allow for these huge chewing muscles”, says Angeline Leece at Southern Cross University in New South Wales, Australia. It also had “hyper-thick enamel” and “enormous back teeth”, she says. Indeed, it has been argued that, relative to its weight, Paranthropus had the biggest jaws and teeth of any primate that ever lived. It is understandable, then, that researchers initially concluded that these ape-people dined on hard foods. The first skull of P. boisei – found by palaeoanthropologist Mary Leakey in the 1950s – actually became known as “Nutcracker Man”.
"As we have learned more about Paranthropus in the past 20 years, it has become clearer that the catchy nickname isn’t really suitable....Instead, the growing consensus is that Paranthropus probably ate a lot of tough, chewy foods, including grasses. The evidence for this is particularly clear for P. boisei. Analyses of the carbon in their teeth show that they ate a lot of plants that used C4 photosynthesis – which basically means grasses and the grass-like sedges.
***
"...described the first partial skeleton of P. boisei, in the form of 1.34-million-year-old arm and leg bones found in Tanzania’s Olduvai gorge. The bones were big and chunky, confirming that it wasn’t just Paranthropus‘s teeth that were robust.
"More bones appeared a few years later, discovered by Green and his colleagues at Ileret in Kenya...Given the “massive” upper arm bone, Green says it is likely that Paranthropus was better at climbing trees than modern humans.
“It makes sense for me,” says Reed. Paranthropus wasn’t particularly fast and had no natural armour. “How are you going to defend yourself against three different species of hyenas, sabre-toothed cats, lions, giant-sized predators?” she says. “Climb a tree.”
***
"P. robustus from a site in South Africa had distinctively shaped cochleas, the part of the ear that turns sounds into signals for the brain. The cochleas would have been unusually sensitive to low-frequency noises. Braga suggests that Paranthropus could make low-pitched sounds, which would travel great distances.
"This is all quite different from anything we imagine as human: something that chewed grass like a cow, rumbled like an elephant and climbed trees like a chimpanzee. In other words, we are left with the impression that Paranthropus were nothing like our human ancestors in terms of diet and behaviour. Arguably, then, we are close to solving the mystery of how and why they survived for so long in a world increasingly dominated by humans: Paranthropus just weren’t competing with humans for food or living space.
***
"A 2021 study of sediments from Kenya found evidence that carbon dioxide levels rose between 1.3 million and 0.7 million years ago, causing P. boisei‘s favoured grasses to become less common. This shift in vegetation would have created a pressure to evolve or die.
“'That would make sense,” says Leece. Paranthropus was “the mammoth of the hominins”, she suggests, referring to the latter’s presumed demise due to rapid changes to dietary flora in its habitat. “They got so far down this hyper-specialised adaptive route that when they hit another source of pressure, they weren’t able to adapt away from it quickly enough. That left them kind of cornered in a niche that was no longer viable for them.”
***
"But Paranthropus wasn’t just an evolutionary dead end. For one, it is a reminder that for most of hominin history, many species coexisted. “It’s an absolute anomaly for us to be the only species of hominin on the landscape right now,” says Leece.
"For another, there is still the intriguing – if speculative – idea that Paranthropus live on in all of us, having interbred with early humans and so potentially contributed small amounts of DNA to our species. They and early humans probably shared a common ancestor around 3 million years ago, and it can take a long time before seemingly separate species can no longer interbreed. (my bold)
Comment: this article changes my view of Paranthropus as very ancient. We need their DNA to answer the question of interbreeding.
Human evolution: no language development
by David Turell , Tuesday, November 28, 2023, 23:36 (359 days ago) @ David Turell
Until colonization in Vanuatu:
https://www.scientificamerican.com/article/an-ancient-art-form-topples-assumptions-abou...
"My investigation took me further than I could have imagined. By watching expert sand artists, learning about their methods, collecting drawings and history and exploring the work of 20th-century ethnologists, I have developed a mathematical model of sand drawing. My work shows that these artworks can be modeled as the result of algorithms and operations of an algebraic nature. Indeed, mathematical language turns out to be appropriate for describing the work of sand drawing experts. Furthermore, sand drawing can help us understand the relationships that Vanuatu societies maintain with their environment.
"Vanuatu is an archipelago with a population of some 315,000 people spread throughout 83 islands. The country has the highest linguistic density in the world, with 138 vernacular languages. The two official languages taught in school are French and English. Bislama, or bichlamar, an Anglo-Melanesian pidgin used in Vanuatu, is the common language.
"Cultures vary in the north and south of the country and even within the same island. The sand drawing practice is widespread only in some central islands, for example. Although the tradition is reminiscent of drawings done on soil in Tamil Nadu, India, it is unique in many ways. In 2008 UNESCO classified the sand drawing of Vanuatu as part of the intangible cultural heritage of humanity.
***
"Although it is difficult to know how many designs are in use, it is clear that, over time, new ones appear, and others disappear. A system very close to intellectual property protects these drawings, making access to this traditional knowledge sometimes sensitive and challenging.
"These artworks are multidimensional in their significance. Some iconic drawings of animals, insects or plants are closely linked with the beliefs, cosmogonies, social organization or even traditions of these societies—which are grouped together under the generic name of kastom. The drawings can also support narratives; they reveal the ethical or political dimensions of societies in central Vanuatu. In many cases, each design bears a vernacular name related to these different aspects.
***
"Ascher observed that in the sand drawings, the line traced in the sand was comparable to a graph whose vertices included all the crossings created in the pattern. The edges were all the arcs between those vertices. These graphs were also Eulerian, meaning that the sand artist had to visit each edge only once and had to return to a starting point. Ascher also documented the number of edges per vertex, which mathematicians call the “degree” of the vertex. This was important because, according to Euler’s theorem, created by mathematician Carl Hierholzer, a connected graph is Eulerian only if each vertex has an even degree.
***
"Today these societies recognize this practice as a traditional graphic art that helps people recall ritual, religious and environmental knowledge. In addition, Jief Todali, a chief whom I met in the Raga region, explained to me that the artists are spokespeople: “Before the arrival of the tuturani [the white foreigners], the people of northern Pentecost did not know how to speak. They expressed themselves through drawings that they traced on the ground with their fingers. Instead of people, the rocks, the stones, the ground of the hills and valleys, the wind, the rain, the water of the sea spoke. But now the situation is reversed. It is the people who speak, and the earth, the wind, the rain and the sea are silent. Now [the people from the Raga region] sometimes say, ‘We have to speak for the land because it can no longer speak for itself.’” (my bold)
***
[b"From beginners to experts, everyone follows a set of “rules.” Because these communities have an oral tradition, there is no written record, [/b] (my bold)
***
"These results raise questions about the universality of mathematics and the form that math takes in other cultures. They open up perspectives for teaching mathematics as well. Since 2010 the acquisition of traditional knowledge such as sand drawing has been one of the objectives of Vanuatu schools, and it is part of a larger movement to decolonize education, much like efforts in Hawaii and in the French territory of New Caledonia. In the current school curriculum, however, no link is made between sand drawing and mathematics. To that end, Vanuatuan Pierre Metsan, a doctoral student in education at the University of New Caledonia, is studying whether the practice of sand drawing could support mathematics instruction. We can look forward to what he learns from this investigation in the years to come."
Comment: amazing that these Pacific Island folk had no real language until white explorers came, but had these mathematically correct sand diagrams, which underlying math was unknown to them. I would think there was some form of oral communication, but no real formal language before the English and French arrived. I'm sure Pidgin developed quickly since 138 dialects emerged.
Human evolution: fetal language learning
by David Turell , Wednesday, November 29, 2023, 16:19 (358 days ago) @ David Turell
edited by David Turell, Wednesday, November 29, 2023, 16:25
Studies from before birth to after:
https://www.science.org/doi/10.1126/sciadv.adj3524?utm_source=sfmc&utm_medium=email...
"Human infants acquire language with amazing ease. This feat may begin early, possibly even before birth, as hearing is operational by 24 to 28 weeks of gestation. The intrauterine environment acts as a low-pass filter, attenuating frequencies above 600 Hz. As a result, individual speech sounds are suppressed in the low-pass–filtered prenatal speech signal, but prosody, i.e., the melody and rhythm of speech, is preserved. Fetuses already learn from this prenatal experience: Newborns prefer their mother’s voice over other female voices and show a preference for the language their mother spoke during pregnancy over other languages. After birth, as infants get exposed to the full-band speech signal, they become attuned to the fine details of the sound patterns of their native language by the end of the first year of life. What neural mechanisms allow the developing brain to learn from language experience remains, however, poorly understood. Here, we asked whether stimulation with speech may induce dynamical changes able to support learning in newborn infants’ brain activity, and whether this modulation is specific to the language heard prenatally.
***
"Together, these results provide the most compelling evidence to date that language experience already shapes the functional organization of the infant brain, even before birth. Exposure to speech leads to rapid but lasting changes in neural dynamics, enhancing LRTCs [long-range temporal correlations] and thereby increasing infants’ sensitivity to previously heard stimuli. This facilitatory effect is specifically present for the language and the frequency band experienced prenatally. These results converge with observations of increased power in the electrophysiological activation of the newborn brain after linguistic stimulation and suggest that the prenatal period lays the foundations for further language development, although it is important to note that its impact is not deterministic, as children, if exposed young, remain capable of acquiring a language even in the absence of prenatal experience with it, e.g., in the case of preterm infants, immigrant or international adoptee children, or after cochlear implantation.
"Whether the facilitatory effect of prenatal experience is specific to the speech domain remains an open question. Behaviorally, it has been shown that newborns recognize music they had been exposed to prenatally, so they show behavioral evidence of learning in auditory domains other than language."
A review of the study:
https://mail.google.com/mail/u/0/#inbox/FMfcgzGwHpbcCjXjcCbgPGvRSnbkKktC
"Fetuses gain the ability to hear sometime between five and seven months gestation. Previous studies had indicated that during this time, they learn to recognize the sounds of music and speaking voices they hear. But whether they really pick up on the language in either has remained unclear. So, researchers fitted one- to five-day-old newborns with electroencephalography (EEG) caps to measure their brain activity. Then they played kids’ stories in English, Spanish, and French—the last of which was their parents’ language. When the French story came at the end, the newborns’ brains reacted differently, exhibiting brain wave patterns that suggested they were already primed to learn their parent’s tongue, according to the authors.
“'These results provide the most compelling evidence to date that language experience already shapes the functional organization of the infant brain, even before birth,” the team writes."
Comment: more discrete evidence the human brain is built to learn language quickly. I believe when sapiens arrived on the scene 315,000 years ago this ability was present by design for future use, considering language is believed to have appeared in fairly full form 50-75,000 years ago. A clear demonstration of design in advance of future use.
Human evolution; selecting stone for tools
by David Turell , Saturday, December 02, 2023, 20:28 (355 days ago) @ David Turell
It involved conceptual thinking for choices:
https://phys.org/news/2023-12-paleolithic-humans-understood-properties-stone.html
"A research group led by the Nagoya University Museum and Graduate School of Environmental Studies in Japan has clarified differences in the physical characteristics of rocks used by early humans during the Paleolithic. They found that humans selected rock for a variety of reasons and not just because of how easy it was to break off. This suggests that early humans had the technical skill to discern the best rock for the tool.
***
"As Homo sapiens moved from Africa to Eurasia, they used stone tools made of rocks, such as obsidian and flint, to cut, slice, and craft ranged weapons. Because of the significant role they played in their culture, understanding how early humans made stone tools is important to archaeologists.
***
"The team analyzed flint nodules in the outcrops that were exploited during the Middle and Upper Paleolithic (70,000 to 30,000 years ago).
"They believe Paleolithic humans understood which rocks were appropriate for making tools and, therefore, intentionally searched for them. According to their hypothesis, Paleolithic humans intentionally searched for flint that was translucent and smooth, as it could be easily broken off the rock face and shaped into sharp edges.
***
"...the researchers found that much of the fine-grained flint in the area suffered from abundant internal fractures caused by geological activities, which would have made it unsuitable for large stone tools, such as Levallois products and robust blades. Therefore, it seems that Paleolithic humans selected the medium-grained flint for large tools, even though it was a tough material to modify into tools, as it was more likely to last longer.
"This offers a fascinating insight into our ancestors' behavior, as they selected flint based on many factors other than just how easy it was to fracture and could discern the most suitable rock to use to make stone tools.
"Suga is enthusiastic about the findings, which suggest the complexity of our ancestors' behavior. "This study illustrates that the Paleolithic humans changed their choice of raw material to suit their stone tool morphologies and production techniques," he said.
"We believe that these prehistoric humans had a sensory understanding of the characteristics of the rocks and intentionally selected the stone material to be used according to the form and production technique of the desired stone tools. This intentional selection of the lithic raw material may have been an important component of the production of stone tools. This may show some aspect of flexible technological behavior adapted to the situation.'"
Comment: A result that tells us about the human cognitive capacities at that time. It indicates they must have had language and communicative skills of a great quality.
Human evolution: brains grow, colons shrink
by David Turell , Sunday, December 03, 2023, 16:06 (354 days ago) @ David Turell
From a story about u sing fermented foods:
https://www.sciencealert.com/preparing-food-with-microbes-could-be-why-we-now-have-such...
"Researchers propose that a taste for fermented morsels may have triggered a surprising jump in the growth rate of our ancestors' brains.
"In fact, a shift from a raw diet to one that included food items already partially broken down by microbes may have been a crucial event in our brain's evolution, according to a perspective study by evolutionary neuroscientist Katherine Bryant of Aix-Marseille University in France and two US colleagues.
"Human brains have tripled in size over the last two million years of evolution, while human colons have shrunk by an estimated 74 percent, suggesting a reduced need to break down plant-derived food internally.
"We know the timeline and extent of human brain expansion, but the mechanisms allowing energy to be directed to this expansion are more complex and somewhat debated.
The study authors lay out their "external fermentation hypothesis" which shows our ancestors' metabolic circumstances for selective brain expansion may have been set in motion by moving intestinal fermentation to an external process, perhaps even experimenting with preserved foods not unlike the wine, kimchi, yoghurt, sauerkraut, and other pickles we still eat today.
"The human gut microbiome acts like a machine for internal fermentation, which boosts nutrient absorption during digestion. Organic compounds are fermented into alcohol and acids by enzymes, usually produced by the bacteria and yeasts that live in parts of our digestive system such as our colon.
"Fermentation is an anaerobic process, meaning it doesn't require oxygen, so similar to the process in our guts, it can occur in a sealed container. The process produces energy in the form of adenosine triphosphate (ATP), which is an essential source of chemical energy that powers our metabolism.
"The researchers argue it's possible that culturally passed-down ways of handling or storing food encouraged this function to be externalized."
Comment: fermentation of food may have played a role, or not. The striking information offered is comparing human organ sizes with great ape proportions. Our brain is three times larger and our colon one-fourth the size. Our small intestine is twice as large, while other gut parts in humans are one-third ape size. (See the diagram) Obviously what we eat dictates how the gut changed to handle it. From my viewpoint, God may have helped in the design of brain and gut changes.
Human evolution: CRISPR cure for sickle cell
by David Turell , Tuesday, December 12, 2023, 20:18 (345 days ago) @ David Turell
In the USA:
https://www.sciencenews.org/article/first-crispr-therapy-sickle-cell-fda
"On December 8, the U.S. Food and Drug Administration approved the gene-editing therapy for use in patients age 12 years and older. In addition to offering hope of relief for people with severe forms of the painful blood disorder, the treatment, called Casgevy, is the world’s first to genetically tweak cells using the Nobel Prize–winning molecular scissors CRISPR/Cas9
"Another gene therapy for sickle cell disease, called Lyfgenia and developed by biotech company bluebird bio, based in Somerville, Mass., was also approved December 8.
***
"Approximately 100,000 people in the United States, most of them Black or Latino, have sickle cell disease. It is caused by a genetic defect in hemoglobin, the oxygen-carrying protein in red blood cells. Unlike typical blood cells that are bendy enough to slip through blood vessels, sickled blood cells are inflexible and get stuck, restricting blood flow and causing debilitating pain (SN: 2/1/22). People with severe forms of the disease can be hospitalized multiple times a year.
"Having a new treatment option for sickle cell disease can give patients a “new lease on life,” says Kerry Morrone, a pediatric hematologist at Albert Einstein College of Medicine in New York City. People with the disease often miss school, work or special events due to excruciating pain. “The potential that this therapy could alleviate symptoms for patients is very exciting.”
***
"Casgevy is like a transplant, but instead relies on a patient’s own cells. Using CRISPR, the treatment alters the genetic blueprint of bone marrow cells that give rise to blood cells. The edited cells make fetal hemoglobin, a type normally made by fetuses and young babies that doesn’t make red blood cells sickle and gum up vessels.
***
"Casgevy is like a transplant, but instead relies on a patient’s own cells. Using CRISPR, the treatment alters the genetic blueprint of bone marrow cells that give rise to blood cells. The edited cells make fetal hemoglobin, a type normally made by fetuses and young babies that doesn’t make red blood cells sickle and gum up vessels.
"Patients first receive chemotherapy to wipe out existing bone marrow cells so the new ones, which are edited in a lab, have a chance to thrive in the body. After editing, the cells are given back to the patient through an IV. Both steps require hospitalization.
"In a clinical trial, 29 out of 30 patients given Casgevy and followed for at least 16 months didn’t have pain crises for at least a year, Vertex vice president of clinical development William Hobbs said at the FDA advisory committee meeting.
"The treatment isn’t without risks. Chemotherapy, for instance, can raise the risk of blood cancer and cause infertility. And in the short-term, chemotherapy kills immune cells, putting patients at higher risk dying from infections. (my bold)
"For some patients those risks may pale in comparison to the prospect of a year without immense pain, says Morrone, who is also director of the Sickle Cell Program at the Children’s Hospital at Montefiore. Others may want to wait and see what the outcomes are. “I think that’s fair, because it’s not without any risk.'”
Comment: note the bold showing it is risky to alter our immune system. Humans acting God-like with our God-given brains still aren't equal to God.
Human evolution: the current obesity crisis
by David Turell , Friday, December 15, 2023, 16:59 (342 days ago) @ David Turell
New drugs can reduce obesity:
https://mail.google.com/mail/u/0/#inbox/FMfcgzGwJJWwHbFwcZVttjFNMXzZpMpl
"Glucagon-like peptide-1, or GLP-1 for short, is often referred to as a gut hormone, but it ultimately affects organs all over the body, from the stomach to the brain. It became clear early on in researching the hormone that it plays important roles in regulating blood sugar, which led to diabetes drugs that mimic its effects by activating the GLP-1 receptor. These drugs that have come to be called GLP-1 receptor agonists.
"Early on, doctors noticed that people taking these drugs also often lost weight, and in 2014, the U.S. FDA gave one of these drugs approval for treating obesity. Still, it wasn’t until the development of a version that could be taken weekly instead of daily that GLP-1 receptor agonists really caught on as weight loss drugs.
***
"Unlike their predecessors, GLP-1 receptor agonists are highly effective weight loss drugs with generally limited and manageable side effects. That makes them a game-changer for the many people for whom excess weight does have knock-on health issues. Clinical trials suggest they improve heart health and kidney disease in people with obesity or diabetes, and they’re being tested in other conditions too, including drug addiction. “In honoring these therapies, we also acknowledge the uncertainties, even anxieties, this sea change brings,” she writes. “We recognize, too, that obesity comes with medical and social complexities, and that many deemed overweight by others are healthy, and have little desire or pressing need to lose weight.'”
"Other concerns about these drugs include that they’re expensive and people may need to take them their entire lives. As Science Editor-in-Chief Holden Thorp writes in this week’s editorial, “for all their promise, GLP-1 receptor agonists have raised more questions than they have answered—a hallmark of a true breakthrough.”
A comment from Science: https://www.science.org/content/article/breakthrough-of-the-year-2023
"Obesity plays out as a private struggle and a public health crisis. In the United States, about 70% of adults are affected by excess weight, and in Europe that number is more than half. The stigma against fat can be crushing; its risks, life-threatening. Defined as a body mass index of at least 30, obesity is thought to power type 2 diabetes, heart disease, arthritis, fatty liver disease, and certain cancers."
Comment: it still is a matter of calories. Our ancestors had to go find their food and burn calories. What they found or hunted was small amounts. We order it up. No wonder the difference a sedentary existence makes.
Human evolution: an example of poor control of Earth
by David Turell , Monday, December 18, 2023, 17:43 (339 days ago) @ David Turell
The Mississippi river water allocation mess:
https://www.sciencedaily.com/releases/2023/12/231215015507.htm
"At the start of World War I, a scientist named Eugene Clyde La Rue hiked the American West to estimate how much water flows down the Colorado River. His findings were ignored, but leaders today don't have to make the same mistake.
***
"Ge's presentation centers around a decision made in 1922, when the seven men who made up the Colorado River Commission came to an agreement to divvy up water on the Colorado River.
"This waterway winds over 1,450 miles and through seven states.
"The commission relied on an estimate from the U.S. Reclamation Service suggesting that 16.4 million acre-feet of water ran through the river at Lees Ferry, Arizona, every year.
"(An acre-foot equals the amount of water you'd need to submerge an acre of land to a depth of 1 feet).
"But, Ge said, the commission also failed to consider a second, less convenient study from 1916.
"Relying on his own field data, La Rue, working for the U.S. Geological Survey, had calculated that the Colorado River discharged just 15 million acre-feet of water.
***
"In 2022, Lake Mead and Lake Powell, the two main reservoirs on the Colorado River, dried up to levels never seen before, raising concerns that they could be heading for a "dead pool" state -- in which water could flow in but not out of the reservoirs.
"Currently, the seven states within the Colorado River Compact are working to revise a suite of agreements and guidelines by 2026.
"Ge hopes that, this time, leaders will work closely with scientists and a range of community members, particularly Indigenous groups -- all to build a Law of the River that accounts for how much water actually exists in the West, now and in the future.
"That will become more important, she said, as climate change continues to melt the West's dwindling snowpacks.
***
"Think of it as a tale of two estimates.
***
"To come to its 16.4 million acre-feet assessment, in contrast, the Colorado River Commission, led by Secretary of Commerce and future President Herbert Hoover, relied on a much less rigorous study: measurements taken at just one site near Yuma, Arizona, hundreds of miles south of Lees Ferry.
""They took the larger number," Ge said. "A larger number probably made the allocations easier to negotiate because there was more water to divvy up."
"To come to its 16.4 million acre-feet assessment, in contrast, the Colorado River Commission, led by Secretary of Commerce and future President Herbert Hoover, relied on a much less rigorous study: measurements taken at just one site near Yuma, Arizona, hundreds of miles south of Lees Ferry.
"'They took the larger number," Ge said. "A larger number probably made the allocations easier to negotiate because there was more water to divvy up."
"The 40 million people who depend on the Colorado River for their water today may be paying the price.(my bold)
"Today, research pegs the flow of the Colorado River at around 13 million acre-feet per year, making even La Rue's modest estimates seem like a fantasy.
"The Colorado River Compact, however, continues to allot water based on the 16.4 million acre- feet value: Colorado, New Mexico, Utah and Wyoming together claim 7.5 million acre feet.
"Arizona, California and Nevada get the same, and Mexico supposedly draws 1.4 million.
"Ge hopes that, in the lead up to 2026, those seven states will do what Hoover couldn't -- draw on the best available science to develop realistic estimates of how much water will likely flow down the river decades from now.
"She added that Indigenous groups need to be an important part of that process.
"Several tribes hold some of the most senior rights to water in the western U.S. but lack the infrastructure to access much of their share. (my bold)
"""
"'We're not talking enough about how much water is in the Colorado River," Ge said. "We talk about droughts, infrastructure and water conservation. But shouldn't the first order of business be to see how much water we actually have? It's much less than we think.'"
Comment: We have made a mass of the river's water resource. If we are to continue to run the Earth, we've got to do a better job. As a veteran Colorado small vessel rafter, I can tell you the dams have made a terrible ecological mess, especially when they release too much water for the shorelines to tolerate, tearing them up. And when the tribes exert their treaty rights, it will only deepen the mess.
Human evolution: how as family we differ
by David Turell , Tuesday, December 19, 2023, 18:46 (338 days ago) @ David Turell
A new study of human aging:
https://www.sciencealert.com/growing-old-could-have-played-a-critical-role-in-our-evolu...
"Once assumed to be an inevitable consequence of living in a rough-and-tumble world, aging is now considered something of a mystery. Some species barely age at all, for example. One of the big questions is whether aging is simply a by-product of biology, or something that comes with an evolutionary advantage.
"The new research is based on a computer model developed by a team from the HUN-REN Centre for Ecological Research in Hungary which suggests old age can be positively selected for in the same way as other traits.
"In recent years, scientists have looked into the inevitability of aging and the associated deterioration of the body (technically known as senescence). What the model suggests is that in certain situations, it can be beneficial to a species.
***
"...it is possible that in a changing environment, aging and death are more advantageous for individuals, because this way the competition, which hampers the survival and reproduction of the more adaptable progeny with better gene compositions, can be decreased," says Szathmáry.
"In other words, natural aging and death leaves space for a new generation that just might have better combinations of genes.
"The researchers also suggest that having more generations sticking around through a drawn-out senescence in organisms that are strongly altruistic would be favored by kin selection. In other words those that help their relatives create a new generation have their long-aging genes passed on more often through them.
"While humans as a species might be obsessed with stopping aging, it seems that senescence has an important role to play in terms of evolutionary advantage – a role that experts are still trying to explore and understand.
"'It has become accepted in the evolutionary biology community that the classical non-adaptive theories of aging cannot explain all the aging patterns of nature, which means the explanation of aging has become an open question once again," says Szathmáry."
Comment: there are species living hundreds of years, many just a few. WE don't know why. The previous entry poses the help grandparents give, but alternatively the elderly need help from others.
Human evolution: homo habilis reconsidered
by David Turell , Friday, January 19, 2024, 19:36 (307 days ago) @ David Turell
This ancestor may be more primitive than originally proposed:
https://evolutionnews.org/2024/01/fossil-friday-new-research-questions-the-human-nature...
"Last year, I wrote an article (Bechly 2023) for Fossil Friday about the questionable status of the East African fossil hominin Homo habilis as a member of our genus rather than being just another ape-like australopithecine. This is a crucial issue for human origins, because Homo habilis is often proclaimed as the transitional form connecting our genus with australopithecines. As I elaborated in my article, this notion was challenged by several mainstream experts, and it was challenged from quite early on (e.g., Wood 1987). But this challenge is far from being a thing of the past. Two new articles relevant to the status of Homo habilis appeared last year in the 50th anniversary edition of the Journal of Human Evolution.
***
"In other words, based on our current knowledge of the fossil record and the human brain, the scientists did not find compelling the claims of Tobias (1987) who had originally “suggested that the neuroanatomy of this species evidenced a clear change toward many cerebral traits associated with our genus.”
"It is also quite interesting that the lead author commented on his blog site (Bruner 2022):
"This taxon [Homo habilis], much debated in the last 20 years, has not found a proper taxonomic validation yet, which suggests at least a lack of robust evidence, in this sense. … The attention of the mass media for science and research is prompting a compulsive marketing based on appearance and fast vending news, at the expense of content and quality. Paleontological fields are characterized by issues that can be hardly proven, charming topics, and harmless conclusions (in the sense that they have no direct consequences on people’s welfare). These three features make these fields more sensitive to contamination associated with personal, institutional, and economic interests, generating a conflict between scientific proficiency and public visibility. Excessive speculations, in this sense, can seriously harm the reputation of the discipline.
***
"...the second article was published by Antón & Middleton (2023), who re-evaluated the fossil record of early Homo, especially H. erectus, H. habilis, and H. rudolfensis. Their conclusion is jaw-dropping: “Chronologically and morphologically H. erectus is a member of early Homo, not a temporally more recent species necessarily evolved from either H. habilis or H. rudolfensis”. So much for the latter two taxa as missing links between ape-like australopithecines and real humans of the genus Homo. Homo erectus coexisted with Australopithecus and tools associated with “Homo” habilis may have been used by Homo erectus on Australopithecus habilis rather than being produced and used by the latter, which is suggested by the distribution of fossils and artifacts at the Olduvai gorge site in Tanzania (Bechly 2023). Habilis was likely not a handy man but the ape bush meat of real humans.
"This is not just my humble opinion, but is also supported by a brand-new study by Davies et al. (2024) in Nature Communications on the dental morphology of Homo habilis. The authors found this “morphology in H. habilis is for the most part remarkably primitive, supporting the hypothesis that the H. habilis hypodigm has more in common with Australopithecus than later Homo.”
"Thus, the most recent research confirms the previous and early critique that H. habilis should be classified as Australopithecus. So, the latter view cannot be dismissed as obsolete and outdated science, and it can also not be dismissed by a mere appeal to a scientific consensus. Science is not about consensus but about empirical evidence and rational arguments. A consensus is scientifically worthless when it is driven by worldview bias and peer pressure rather than by an unbiased inference to the best explanation. Here is what Jurassic Park author Michael Crichton famously said about this issue: “I regard consensus science as an extremely pernicious development that ought to be stopped cold in its tracks. Historically, the claim of consensus has been the first refuge of scoundrels; it is a way to avoid debate by claiming that the matter is already settled.'”
Comment: Bechly's opinions aside, it appears homo habilis is probably more ancient than originally thought. As for 'consensus' it has to be arrived at by many people researching and a meld of personal opinions reaches an accepted conclusion.
Human evolution: our gut's big brain
by David Turell , Saturday, January 20, 2024, 19:15 (306 days ago) @ David Turell
Covered by neurons and glia:
https://neuroscience.ubc.ca/our-second-brain-more-than-a-gut-feeling/
"...how do the brain and gut actually talk to each other?
"A thick cable of neurons runs between the base of the brain and our gut forming the vagus nerve, the longest cranial nerve in our body. The vagus nerve serves as a bidirectional information highway, with the brain and gut sending messages to each other within the order of milliseconds.
"The vagus nerve isn’t the only way the brain and gut communicate. Our guts are home to trillions of bacteria and microbes that inhabit the intestines and form the gut microbiota. The gut microbiome is so enormous that there are 100,000 times more microbes in your gut than there are people on earth.
"Many of these microbes live in the mucus layer that lines the intestines, placing them in direct contact with nerve and immune cells, which are the major information gathering systems of our bodies. This location also primes microbes to listen in as the brain signals stress, anxiety or even happiness along the vagus nerve.
"But the microbes in our gut microbiome don’t just listen. These cells produce modulating signals that send information back up to the brain. In fact, 90% of the neurons in the vagus nerve are actually carrying information from the gut to the brain, not the other way around. This means the signals generated in the gut can massively influence the brain.
***
"The crosstalk along the gut–brain axis helps make sense of the accumulating evidence that the gut is involved in brain health and disease. Many neurological conditions, such as Parkinson’s disease, Alzheimer’s disease, schizophrenia, and autism spectrum disorder are correlated with gastrointestinal issues or altered gut microbiomes.
"Recent research on Parkinson’s disease found that the enteric nervous system begins to degenerate before the classical symptoms of Parkinson’s appear, and a dysfunctional gut microbiome is typical of this disease. Further, there is a significant decrease in the quantity of microbes in the gut microbiome of individuals with Alzheimer’s disease, and an unhealthy diet is a commonly cited risk factor for Alzheimer’s.
"One explanation for this is the role of inflammation, which is a chronic symptom in many neurological conditions. Disruption in the health of the gut microbiome can trigger an immune response and lead to inflammation. Over 70% of the body’s immune cells are targeted to the digestive tract—which is helpful in the case of ingesting toxic bacteria—but also means a gut-immune response can launch a powerful inflammatory response in the body.
"Inflammation is also a hallmark of mental illness and may explain the link between gut and mental health. For example, a recent study reported that a significant number of patients with inflammatory bowel disease also suffered from depression and anxiety.
"Both the vagus nerve and gut microbiota are likely involved in this. Stimulation of the vagus nerve has been shown to reduce inflammation and stress, and some researchers are even suggesting that vagus stimulation could be a new drug-free antidepressant. Certain healthy gut bugs like the probiotic Lactobaccilus rhamnosus, can even send signals to neurons to release GABA, a neurotransmitter that promotes calmness. Gut microbes also promote neuroplasticity, a process implicated in mood.
"While it is now apparent that the gut is more than just a machine for digesting food, there is still much to be discovered in terms of how the gut can influence overall health. As our understanding of the gut–brain axis increases, there is the exciting possibility that improving gut health may lead to breakthroughs for treating brain disorders."
Comment: this subject is reintroduced as the importance of the gut/brain relationship has been emphasized by recent studies. Past study: 2021-10-01, 23:41. I'll ask the same question as before. Since this is an internal function not challenged by external events, how does Darwinian theory account for this evolution? It goes way back to the first mammals. Only intellient design fits.
Human evolution: our gut can control weight
by David Turell , Sunday, January 21, 2024, 16:24 (305 days ago) @ David Turell
There are natural obesity control mechanisms:
https://www.sciencealert.com/your-body-has-a-built-in-weight-loss-system-you-may-not-kn...
"Wegovy, Ozempic and Mounjaro are weight loss and diabetes drugs that have made quite a splash in health news. They target regulatory pathways involved in both obesity and diabetes and are widely considered breakthroughs for weight loss and blood sugar control.
***
"It turns out your body produces natural versions of these drugs – also known as incretin hormones – in your gut. It may not be surprising that nutrients in food help regulate these hormones. But it may intrigue you to know that the trillions of microbes in your gut are key for orchestrating this process.
***
"Specialized bacteria in your lower gut take the components of food you can't digest like fiber and polyphenols – the elements of plants that are removed in many processed foods – and transforms them into molecules that stimulate hormones to control your appetite and metabolism. These include GLP-1, a natural version of Wegovy and Ozempic.
"GLP-1 and other hormones like PYY help regulate blood sugar through the pancreas. They also tell your brain that you've had enough to eat and your stomach and intestines to slow the movement of food along the digestive tract to allow for digestion. This system even has a name: the colonic brake.
"Prior to modern processed foods, metabolic regulatory pathways were under the direction of a diverse healthy gut microbiome that used these hormones to naturally regulate your metabolism and appetite. However, food processing, aimed at improving shelf stability and enhancing taste, removes the bioactive molecules like fiber and polyphenols that help regulate this system.
"Removal of these key food components and the resulting decrease in gut microbiome diversity may be an important factor contributing to the rise in obesity and diabetes.
"Wegovy and Ozempic reinvigorate the colonic brake downstream of food and microbes with molecules similar to GLP-1. Researchers have demonstrated their effectiveness at weight loss and blood sugar control.
"Mounjaro has gone a step further and combined GLP-1 with a second hormone analogue derived from the upper gut called GIP, and studies are showing this combination therapy to be even more effective at promoting weight loss than GLP-1-only therapies like Wegovy and Ozempic.
***
"For the majority of the population who don't yet have obesity or diabetes, restarting the gut's built-in appetite and metabolism control by reintroducing whole foods and awaking the gut microbiome may be the best approach to promote healthy metabolism.
"Adding minimally processed foods back to your diet, and specifically those replete in fiber and polyphenols like flavonoids and carotenoids, can play an important and complementary role to help address the epidemic of obesity and metabolic disease at one of its deepest roots."
Comment: the moral is overly refined foods mess up a natural control system for obesity.
Human evolution: gluing tools
by David Turell , Thursday, February 22, 2024, 16:54 (273 days ago) @ David Turell
Bitumen and ochre don't stick to hands:
https://mail.google.com/mail/u/0/#inbox/FMfcgzGxRnfnxGwbQGxXghLzLXFLtCpq
"When researchers at a Berlin museum decided to reexamine a set of stone tools that had sat untouched in their collection since the 1960s, they were surprised to discover several items covered in curious red and yellow stains. Further analysis of the tools, which were crafted some 40,000 years ago by ancient human relatives in what is now southwestern France, revealed traces of bitumen—a sticky substance used to make asphalt—and a naturally occurring pigment called ochre.
"According to a study published yesterday in Science Advances, Neanderthal toolmakers mixed these two ingredients together to create a surprisingly sophisticated type of glue. When researchers recreated the recipe, it yielded a gummy, malleable adhesive strong enough to hold stone blades, scrapers, and flakes, but not sticky enough to adhere to hands—ideal for making grips for handheld tools.
"While previous research has shown that early modern humans in Africa made compound adhesives using ochre, this new study demonstrates that European Neanderthals were also innovative manufacturers of both glue and tools, and may have had higher levels of cognition and cultural development than previously assumed.
“'What our study shows is that early Homo sapiens in Africa and Neanderthals in Europe had similar thought patterns,” study author Patrick Schmidt said in a press release. “Their adhesive technologies have the same significance for our understanding of human evolution.'”
The original paper:
https://www.science.org/doi/10.1126/sciadv.adl0822?et_rid=825383635&et_cid=5112502
"Abstract
Ancient adhesives used in multicomponent tools may be among our best material evidences of cultural evolution and cognitive processes in early humans. African Homo sapiens is known to have made compound adhesives from naturally sticky substances and ochre, a technical behavior proposed to mark the advent of elaborate cognitive processes in our species. Foragers of the European Middle Paleolithic also used glues, but evidence of ochre-based compound adhesives is unknown. Here, we present evidence of this kind. Bitumen was mixed with high loads of goethite ochre to make compound adhesives at the type-site of the Mousterian, Le Moustier (France). Ochre loads were so high that they lowered the adhesive’s performance in classical hafting situations where stone implements are glued to handles. However, when used as handheld grips on cutting or scraping tools, a behavior known from Neanderthals, high-ochre adhesives present a real benefit, improving their solidity and rigidity. Our findings help understand the implications of Pleistocene adhesive making."
Comment: making a workable compound glue, not sticky to hand is a highly complex invention, which also involved travel to reach each of the ingredients. It shows how bright the Neanderthals were.
Human evolution: common responses to music we make
by David Turell , Tuesday, February 27, 2024, 23:39 (268 days ago) @ David Turell
Seems universal:
https://www.realclearscience.com/blog/2024/02/27/do_all_humans_feel_music_the_same_way_...
"Forty-three thousands years ago, our ancestors were making music. We know this because scientists have found unmistakable prehistoric flutes made of bone and ivory in caves nestled within a mountain range in southwest Germany. The discovery clarifies that humans evolved with rhythm and melody for at least tens of thousands of years, possibly far longer. (Alas, anthropologists will never find concrete evidence of singing; vocals don’t fossilize.)
"The fact that music has been with us for so long explains why it affects us so profoundly — both mentally and physically.
***
"Even infants will nod their heads and tap their feet when hearing catchy tunes. Scientists armed with fMRI scanners have found that music activates the sensory-motor regions of the brain. Furthermore, music alters heart rate, skin conductance, respiration, and body temperature. It also adjusts the levels of hormones like cortisol, oxytocin, and prolactin.
"So, yes, there’s copious scientific evidence that humans literally feel music, but are the sensations universal? If humans from different cultures listen to the same songs, will they physically react in the same way?
"That’s what a team of Chinese and Finnish researchers wanted to find out. In an experiment recently described in the Proceedings of the National Academy of Sciences, they presented nearly 2,000 participants from the United Kingdom, the United States, and China with a dozen excerpts from different songs and asked them to describe where they felt the music in their bodies. For this, the researchers gave each subject blank silhouettes of a human body and asked them to color the regions where they felt changing activity.
***
"The researchers found that both Western and Chinese participants physically responded to the songs in nearly identical fashions.
“Across both cultures, happy and danceable songs activated the arms, legs, and the head. In contrast, sad, tender, and scary songs activated mainly the chest and head regions while for the aggressive songs, the activation was mostly focused on the head,” the researchers described. “Given the cultural consistency of these effects, the results suggest similar embodiment of musical emotions across distant cultures and point toward a biological component in music-induced bodily sensations.”
"Furthermore, the results show that humans feel music in the same way regardless of language and familiarity. Participants from both Western and East Asian cultures were not very familiar with the other’s songs. Instead, their bodies were responding to specific acoustic and structural cues.
"What accounts for the different ways humans feel music? Sensations in the chest could reflect changes in heart rate and respiration, the researchers say. Meanwhile, the urge to move to a steady beat could be from the brain making predictions about the musical pulse.
"The authors caution that their experiment only analyzed two cultures, meaning it’s possible that a disparate group of humans living in a remote part of the world would react to music very differently.
"A few years ago, scientists with the Durham University Music & Science Lab ventured to the Hindu Kush mountains of Pakistan. Their goal was simple: play various types of music for the tribal peoples there and gauge their reactions and thoughts. Lacking stable access to electricity, the tribes’ connection with the outside world was tenuous at best. So, these groups had little to no experience with other kinds of music. Would their emotional responses be drastically different from those of humans living in connected societies?
"The researchers uncovered broad commonalities but also several subtle, yet intriguing differences. While music is universal, culture can — to an extent — affect our emotional responses to it."
Comment: we all have felt the pull of music and rhythms. I view it like maths: the numbers have always been there for us to find and discover simple and complex relationships. The sounds are the same, always there to find, to join and enjoy. Perhaps, a gift from God?
Human evolution: how we lost our tails
by David Turell , Thursday, February 29, 2024, 01:25 (266 days ago) @ David Turell
A genetic transposon:
https://www.sciencenews.org/article/genetic-parasite-humans-apes-tail-loss-evolution
"Around 25 million years ago, this parasite, a small stretch of repetitive DNA called an Alu element, ended up in a gene important for tail development, researchers report in the Feb. 29 Nature. The single insertion altered the gene Tbxt in a way that seems to have sparked one of the defining differences between monkeys and apes: Monkeys have tails, apes don’t.
***
"Alu elements are part of a group of genetic parasites known as transposons or jumping genes that can hop across genetic instruction books, inserting themselves into their hosts’ DNA (SN: 5/16/17). Sometimes, when the gene slips itself into a piece of DNA that is passed down to offspring, these insertions become permanent parts of our genetic code.
"Transposons, including more than 1 million Alu elements, are found throughout our genome, says geneticist and systems biologist Bo Xia of the Broad Institute in Cambridge, Mass. Researchers once thought of transposons as genetic garbage, but some have central roles in evolution. Without transposons, the placenta, immune system and insulation around nerve fibers may not exist.
***
"The team found that in monkeys, including baboons and rhesus macaques, the Tbxt gene was missing a chunk of DNA that’s found in humans, chimpanzees and other apes. It was a “eureka moment,” Boeke says. The insertion may have appeared around the time apes diverged from African and Asian monkeys, around 25 million years ago.
"But the missing chunk was in a part of the gene called an intron, a bit of genetic material that isn’t made into proteins. “So why would that even matter?” he asks. A close look at the gene’s structure provided a plausible explanation: The missing bit tweaked Tbxt so that the gene makes a different form of the protein in apes than in monkeys.
***
"The new findings do begin to unravel how apes lost their tails, says Gabrielle Russo, a biological anthropologist at Stony Brook University in New York. But why it happened, she says, is a much harder question to answer. Research from the early 1900s linked tail loss to muscle changes that helped human bodies move upright, but shifts in posture, as well as learning to walk on two feet, didn’t happen until millions of years later (SN: 9/15/21; SN: 4/14/21). So, it’s unlikely the new findings will shed light on these human traits, Russo says."
Comment: apes don't have upright posture, tails or not. We are exclusively very different. We are not naked apes, as we were previously called!!!
Human evolution: defining human personhood
by David Turell , Saturday, March 09, 2024, 19:18 (257 days ago) @ David Turell
A philosophy of humanhood:
https://evolutionnews.org/2024/03/the-humanity-and-personhood-of-an-embryo/
"At the heart of the abortion debate are two sets of questions: scientific questions and moral questions. They are both important, and much of the rancor and division in the abortion debate stems, I think, from conflation of scientific and moral issues. They are not the same. Properly formed moral views depend on correct scientific understanding. If we don’t know what a fetus is, scientifically, we are hampered in making sound moral judgments about its protection.
***
"A sperm and an egg separately constitute a potential human. But when they unite, the result is a human being from the moment of fertilization. Human beings are not defined by the number of cells in the body — be it one cell or 30 trillion cells. A big complex human being is not more human than a small simple human being.
"There is no actual debate about this — the basic biology of human reproduction was understood in the early 19th century, and any doctor or scientist who denies the humanity of a human being in the womb is either ignorant or deliberately misrepresenting science to advance an ideological agenda. (There is a simple scientific answer to the basic question at the heart of the abortion debate. Whatever a “person” is, a human zygote is most certainly a human being.)
"The term “person” is a moral and legal category, not a scientific category, and it is a category open to moral discussion and debate. But “human being” is a scientific term, and it is not open to debate. The science is settled. Human life begins at fertilization, and cogent moral reasoning about abortion must begin with that scientific fact."
Comment: I am pragmatic about this: rape and incest call for abortion as does extremely severe economic hardship. Another reason is proof of a severely deformed fetus based on DNA studies, and I don't mean Downs and others like it.
Human evolution: migrations of Homo erectus
by David Turell , Sunday, March 10, 2024, 16:44 (256 days ago) @ David Turell
Into Europe at 1.4 million years ago:
https://www.sciencealert.com/archaeologists-just-uncovered-the-oldest-evidence-of-human...
"Stone tools found buried deep in the sediment of the Korolevo quarry in Ukraine are rewriting the history of human migration.
The seemingly unassuming chunks of rock are tools once used by Homo erectus, a direct ancestor of ours, and new dating reveals they represent the earliest evidence of hominid habitation on the European continent.
"'Previously it was thought that our earliest ancestors could not survive in colder, more northerly latitudes without the use of fire or complex stone tool technology," says archaeologist Andy Herries of La Trobe University in Australia.
"'Yet here we have evidence of Homo erectus living further north than ever previously documented at this early time period."
***
"Our models are largely based on stone tools, since they – along with some scanty bone traces and a few other robust artifacts – are among the few traces capabile of surviving through the eons. Yet stone artifacts don't come stamped with a production date, leaving researchers to rely on surrounding clues to determine their age and place in history.
***
"'At the Korolevo site, we specifically measured the concentrations of cosmogenic nuclides beryllium-10 and aluminum-26, which have different half-lives," Garba explains.
"'These nuclides accumulate in the quartz grains when the rock is at the surface due to cosmogenic radiation from space, but they begin to decay when they become buried in the ground. The ratio of the two varies according to how long the clasts were buried beneath the ground surface. This allows us to calculate their age since burial."
"The team also used their own mathematical-based modeling to determine the age of the sediment layers, the first time this method has been used for archaeological dating. The earliest age they obtained using this method was 1.42 million years, for the oldest tools in the assemblage.
"The dating of the artifacts has allowed the researchers to fill in some of the gaps in the history of human migration. Their research shows that Homo erectus was in Europe by 1.4 million years ago, having migrated through Asia 1.8 million years ago. The oldest known Homo erectus fossil dates to 2 million years ago, found in fragments in a cave in South Africa and painstakingly pieced together."
Comment: just recently we noted how humans liked to migrate, in this case north out of Africa.
Human evolution: the earliest writing
by David Turell , Tuesday, March 12, 2024, 20:38 (254 days ago) @ David Turell
On a Pacific Island:
https://mail.google.com/mail/u/0/#inbox/FMfcgzGxSHglSHQfdqbdkxSKmfKbRnvg
"Welcome back to Our Human Story, New Scientist’s monthly newsletter all about human evolution and the origin of our species. This month, we’re trying to figure out whether the people of Rapa Nui (Easter Island) invented their own writing.
"When we think about the invention of writing, we generally think about Eurasia and Africa. It might bring to mind Mesopotamia in western Asia and the invention of cuneiform, or perhaps Egyptian hieroglyphics.
"As a rule, we don’t think about isolated Pacific islands. But maybe we should. On Rapa Nui in the eastern Pacific, people carved symbols called Rongorongo onto wooden tablets. It has never been deciphered, but many linguists think it’s writing.
"Here is the thing. Europeans first noticed Rongorongo over a century after they first reached the island. So it has been suggested, even assumed, that the Rapa Nui people did not invent it independently, but got the idea from literate Europeans.
"There is now tentative evidence that that story is wrong. One of the wooden Rongorongo tablets seems to be centuries old, meaning it dates from long before the European arrival. The implication is that Rongorongo is nothing less than an independent invention of writing – one that took place in a context drastically dissimilar to all the others where this milestone was passed. It is, as they say, huge if true.
"This is one of those stories with a lot of moving parts. On the one hand, it’s about the technical questions of how old the Rongorongo scripts are and whether they qualify as writing. But it’s also about European prejudices against Indigenous cultures, especially during the colonial period – the consequences of which are still playing out today. (my bold)
Comment: note the bold. Same as the comment in the previous entry today. An influenced of "The Descent of Man'?
Human evolution: handedness origin
by David Turell , Saturday, April 06, 2024, 19:23 (229 days ago) @ David Turell
All theory:
https://www.newscientist.com/article/2425718-left-handed-monkeys-prompt-rethink-about-e...
"Monkeys that adopted an urban lifestyle in India are mostly left-handed – in contrast to humans and many other primates that live on the ground.
"The findings clash with long-standing claims that primates that come down from the trees generally evolve a tendency to be right-handed, raising questions about what really drives this trait.
"The Hanuman langurs (Semnopithecus entellus) – named in honour of Lord Hanuman of Indian mythology – gave up their natural homes in the trees at least 165 years ago and now live off food offerings from people who revere them as gods.
“'Hanumans have a high amount of deity value among the Indians, irrespective of religion,” says Akash Dutta at the University of Calcutta in India. Only 9 per cent of the animals’ natural habitat remains following massive expansion of human settlements, he adds.
"Realising that the monkeys’ behaviours and actions have been evolving over time, Dutta started wondering about the animals’ laterality, or handedness. In particular, he questioned how they might fit into what is known as the postural origin theory.
"This popular, but often debated, concept suggests that the earliest branches of primates lived in trees and were left-handed, using their left hand to grab food or branches while holding onto the tree with their right. Those that later adapted to life on the ground – like humans, 90 per cent of whom are right-handed – switched to having a predominantly right-sided laterality as they could now use their free right hand to handle tools and other objects. This then stimulated the motor skills region in the left side of the brain, which controls the right side of the body – in turn promoting more use of the right hand.
"Studies show that chimpanzees, gorillas, baboons, bonobos and ring-tailed lemurs are mostly right-handed, for example, whereas Sichuan snub-nosed monkeys, deBrazza’s monkeys and orangutans – all of which live in trees – are mostly left-handed.
***
"The researchers handed each monkey a sweet bun trapped inside an open, transparent bottle. Only 27 per cent of the monkeys showed right-handedness in getting the bun out of the bottle. Fifty-three per cent were left-handed, and the rest were ambidextrous or tried using their mouths to extract the bun.
"The results came as a surprise to Dutta. He thinks the explanation may be that the monkeys’ DNA still programs for left-handedness, even after dozens of generations in their new environment. “The ancestral tendency is still there,” he says. He predicts that the urban langurs will shift to right-handedness over time.
"However, Kai Caspar at Heinrich Heine University Düsseldorf in Germany believes the study provides further evidence that the tree-related idea for the evolution of handedness is wrong. “I frankly don’t understand why it still maintains its high status in the research community,” he says.
"His team has already strongly questioned the validity of the postural origins theory – as well as other ideas proposing that the dominance of right-handedness in humans is related to walking erect or developing language. For Caspar, the explanation for handedness has yet to be uncovered."
Comment: I saw an article recently that said there is evidence that handedness is about 25% inherited. That is the first time I've ever seen such a reference. I have special interest in the subject as I am strongly left-handed. One grandfather was said to have had some lefty characteristics.
Human evolution: Neanderthal DNA in humans
by David Turell , Monday, May 20, 2024, 17:38 (185 days ago) @ David Turell
From mating with Neanderthals, 2% remains:
https://www.livescience.com/health/genetics/more-neanderthal-than-human-how-your-health...
"In people who inherited Neanderthal DNA, the X-chromosome also contains a lot less Neanderthal ancestry than other, non-sex chromosomes carry. This is probably because any harmful or nonfunctional mutations on the X chromosome will be expressed in males, because they lack a matching, functional copy of the gene to compensate. That likely created strong evolutionary pressure to remove such harmful Neanderthal genes from the modern human X, Emilia Huerta-Sanchez, an associate professor of ecology, evolution, and organismal biology at Brown University, told Live Science.
"But some Neanderthal DNA helped modern humans survive and reproduce, and thus it has lingered in our genomes. Nowadays, Neanderthal DNA occupies, on average, 2% of the genomes of people outside Africa. However, the frequency of Neanderthal DNA that codes for beneficial traits may be as high as 80% in some regions of the genome, Akey said.
***
"A Neanderthal gene variant on chromosome 9 that influences skin color is carried by 70% of Europeans today. Another Neanderthal gene variant, found in most East Asians, regulates keratinocytes, which protect the skin against ultraviolet radiation via a dark pigment called melanin.
"Neanderthal gene variants are also associated with a greater risk of sunburn in modern humans. Likewise, around 66% of Europeans carry a Neanderthal allele linked to a heightened risk of childhood sunburn and poor tanning ability.
***
"In addition, our ancestors had to adapt to colder Eurasian weather. To do so, they may have acquired Neanderthal genes that affected face shape. In a 2023 study, scientists discovered that modern humans inherited tall-nose genes from Neanderthals. A taller nose may have allowed more cold air to be heated to body temperature in the nose before reaching the lungs, suggested Kaustubh Adhikari, co-senior study author.
***
"Many of the strongly retained Neanderthal genes are tied to immune function.
***
"While many of the ancestral pathogens that sickened ancient humans are lost to time, some of the Neanderthal genes that helped fight them off still work against modern pathogens. For example, a 2018 study by Enard and a colleague revealed that modern humans inherited Neanderthal DNA that helped them combat RNA viruses, a group that today includes the flu (influenza), HIV and hepatitis C.
***
"And even the immune boost from Neanderthals may have a downside. In 2016, scientists discovered that Neanderthal genes that prime the immune system to fight pathogens may also predispose people to allergic diseases. In addition, Neanderthal genes have been tied to a higher risk of developing autoimmune diseases, such as Graves' disease, caused by an overactive thyroid; and rheumatoid arthritis, which inflames the joints and even "Viking disease," in which one or more fingers become bent or frozen.
"One Neanderthal gene variant may have made us more likely to have a severe case of COVID-19. That variant, found on chromosome 3, is found in half of South Asians and one-sixth of Europeans. But even there, the picture is complicated, as other Neanderthal genes, carried by up to half of people in Eurasia and the Americas, are associated with a reduced risk of severe COVID-19.
***
"Figuring out the role of Neanderthal DNA in our genomes does more than help us understand our health. These bits of DNA can provide clues as to what makes us unique, Sankararaman said.
"'Neanderthal DNA entered our genomes at an important time in our history," Sankararaman said, when our ancestors were moving into new environments."
Comment: this answers the question of why so many forms of human ancestors if God was in charge. Why not go directly to sapiens? Both Neanderthal and Denisovan genes have supplied helpful genes. That is an answer.
Human evolution: our heart differs from great ape's
by David Turell , Friday, June 14, 2024, 18:09 (160 days ago) @ David Turell
Different left ventricle:
https://phys.org/news/2024-06-architecture-heart-human-evolution.html
"During these great apes' routine veterinary procedures, the team used echocardiography—a cardiac ultrasound—to produce images of the left ventricle, the chamber of the heart that pumps blood around the body. Within the non-human great ape's left ventricle, bundles of muscle extend into the chamber, called trabeculations.
"Bryony Curry, a Ph.D. student in the School of Health and Exercise Sciences at UBCO, said, "The left ventricle of a healthy human is relatively smooth, with predominantly compact muscle compared to the more trabeculated, mesh-like network in the non-human great apes.
"'The difference is most pronounced at the apex, the bottom of the heart, where we found approximately four times the trabeculation in non-human great apes compared to humans."
***
"Curry said, "We found that the degree of trabeculation in the heart was related to the amount of deformation, rotation and twist. In other words, in humans, who have the least trabeculation, we observed comparatively greater cardiac function. This finding supports our hypothesis that the human heart may have evolved away from the structure of other non-human great apes to meet the higher demands of humans' unique ecological niche."
"A human's larger brain and greater physical activity compared to other great apes can also be linked to higher metabolic demand, which requires a heart that can pump a greater volume of blood to the body.
"Similarly, higher blood flow contributes to humans' ability to cool down, as blood vessels close to the skin dilate—observed as flushing of the skin—and lose heat to the air.
***
"'hat remains unclear is how the more trabeculated hearts of non-human great apes may be adaptive to their own ecological niches. Perhaps it's a remaining structure of the ancestral heart, though, in nature, form most often serves a function.'"
Comment: we were different in design from the beginning. Our heart was built to meet the demands of high-speed running.
Human evolution: our amazingly complex cells
by David Turell , Sunday, June 30, 2024, 16:42 (144 days ago) @ David Turell
Cataloging cells by DNA expression finds we have thousands of differently acting cells:
https://www.quantamagazine.org/new-cell-atlases-reveal-untold-variety-in-the-brain-and-...
"Powerful sequencing and imaging technologies invented in the last decade are revealing with unprecedented detail the composition of human organs and tissues, from the pancreas and liver to the placenta, as well as those of other animals like the mouse and fruit fly. With these new tools, researchers can fingerprint individual cells based on which genes they are expressing. That information has revealed subtle and unsuspected distinctions among cells and has begun to illuminate how the diversity of cell types can be essential to the healthy functioning of organs.
***
"Today in Nature, a coalition of laboratories published nine studies that collectively form a detailed atlas of the mouse brain — the most comprehensive mammalian brain atlas to date. It describes more than 5,300 types of cells found throughout the organ. How these cells are distributed and are related to one another suggests many intriguing ideas about the evolution of the mammalian brain.
***
"Because of that work, it’s clear that the human brain contains at least 3,300 distinct types of neurons, each expressing a different set of genes, which hints that the cells could serve a range of slightly different functions. Much of this diversity, it turns out, is in the less studied and more evolutionarily ancient regions of the brain.
"This human brain cell atlas is merely an early edition. As scientists continue the task of tallying and classifying every single cell in the brain, they will likely identify thousands of additional cell types.
***
"The differences in our cells don’t come from differences in the genes themselves: Every cell in your body contains a copy of your distinctive DNA and the 20,000 genes for making proteins it encodes. “The genome is a parts list,” Quake said. “There’s no way to predict which cell types come out of a given genome.” (my bold)
***
"Using a powerful set of single-cell genomics tools, scientists can read these expression patterns to fingerprint a cell. These tools have matured over the past few years so that scientists can now quickly and efficiently look at tens of thousands or even millions of cells in a single experiment.
***
"With each new cell atlas, researchers have had to reckon with how much complexity they were missing before. Reviewing the data sometimes made Angelo feel as if he were looking at endlessly looping videos of fractals, he said. “You keep zooming in” and the pattern goes on indefinitely; the more you uncover, the more you realize there’s more to uncover. “A lot of this is kind of daunting.”
***
"The analysis revealed “an extreme amount of diversity,” Doege said. They identified more than 350 distinct neuron populations and 19 non-neuron cell populations from 10 different regions within the hypothalamus. (my bold)
***
"Across the entire brain, the research teams discovered more than 3,300 different types of neurons — and that account is surely incomplete. The most comprehensive atlas of the mouse brain to date, published today, identified 5,300 cell types, including both neurons and glia. The project is missing cell census data from some areas, such as the medulla. Still, researchers think that the full count of cell types for the human brain, when it is compiled, will likely be similar.
***
"The findings inside the brain cell atlas alone are dizzying. But then consider that other cell atlases are uncovering similar trends. In organ after organ, researchers seem to be finding a greater diversity of cell types than they expected. These discoveries suggest that the healthy functioning of tissues often depends on having the right mix of cells doing slightly different jobs. Each individual cell atlas therefore provides almost incalculable new possibilities for understanding a region of the body, and all the things that can go wrong with it.
***
"Future cell atlases will probably also probe cell identity more deeply. Most cell maps are looking only at messenger RNA, which is “not even the only kind of RNA in the cell,” Quake said. Moreover, an expressed gene doesn’t necessarily mean that a specific protein is present in a cell. A future goal is to gather data on which proteins and other molecular products are present in single cells, Rhea said."
Comment: the microscopic level is passé. RNA studies will show us how many differently functioning cells exist. We are finally looking at the basis of life's functions as expressed in the cellular genome. Not by chance.
Human evolution: new Denisovan study
by David Turell , Wednesday, July 03, 2024, 19:01 (141 days ago) @ David Turell
In a Tibetan cave:
https://phys.org/news/2024-07-bone-extinct-humans-survived-tibetan.html
"Bone remains found in a Tibetan cave 3,280 m above sea level indicate an ancient group of humans survived here for many millennia, according to a new study published in Nature.
***
"Their new analysis has identified a new Denisovan fossil and shed light on the species' ability to survive in fluctuating climatic conditions—including the ice age—on the Tibetan plateau from around 200,000 to 40,000 years ago.
"Dr. Geoff Smith, a zooarchaeologist at the University of Reading, is a co-author of the study. He said, "We were able to identify that Denisovans hunted, butchered and ate a range of animal species. Our study reveals new information about the behavior and adaptation of Denisovans both to high altitude conditions and shifting climates. We are only just beginning to understand the behavior of this extraordinary human species."
***
"Dr. Huan Xia, of Lanzhou University, said, "Zooarchaeology by Mass Spectrometry (ZooMS) allows us to extract valuable information from often overlooked bone fragments, providing deeper insight into human activities."
"The research team determined that most of the bones were from blue sheep, known as the bharal, as well as wild yaks, equids, the extinct wooly rhino, and the spotted hyena. The researchers also identified bone fragments from small mammals, such as marmots, and birds.
"Dr. Jian Wang, of Lanzhou University, said, "Current evidence suggests that it was Denisovans, not any other human groups, who occupied the cave and made efficient use of all the animal resources available to them throughout their occupation."
"Detailed analysis of the fragmented bone surfaces shows the Denisovans removed meat and bone marrow from the bones, but also indicates the humans used them as raw material to produce tools.
"The scientists also identified one rib bone as belonging to a new Denisovan individual. The layer where the rib was found was dated to between 48,000 and 32,000 years ago, implying that this Denisovan individual lived at a time when modern humans were dispersing across the Eurasian continent. The results indicate that Denisovans lived through two cold periods, but also during a warmer interglacial period between the Middle and Late Pleistocene eras.
"Dr. Frido Welker, of the University of Copenhagen, said, "Together, the fossil and molecular evidence indicates that Ganjia Basin, where Baishiya Karst Cave is located, provided a relatively stable environment for Denisovans, despite its high-altitude.
"'The question now arises when and why these Denisovans on the Tibetan Plateau went extinct.'"
Comment: Both Neanderthals and Denisovan went extinct probably in the same time frame. It is possible roving sapiens drove them to extinction. My guess is it was sapiens not being stronger but more intelligent.
Human evolution: aging footprints in New Mexico
by David Turell , Thursday, July 04, 2024, 16:29 (140 days ago) @ David Turell
At 22,000+ years ago;
https://www.sciencenews.org/article/human-footprints-new-mexico-ancient-dating
"Human footprints in White Sands National Park in New Mexico sparked controversy two years ago when scientists found the prints to be surprisingly old, dating to about 22,000 years ago. Now, two other ways of dating the fossilized tracks converge at similar ages as the first estimate, potentially resolving the dispute, researchers report in the Oct. 6 Science.
'The finding adds to mounting evidence that humans arrived in North America thousands of years earlier than previously thought.
***
"In 2021, researchers described more than 60 footprints embedded in what was once mud alongside an ancient lake in what’s now New Mexico. Radiocarbon dating of an aquatic plant’s seeds in and around the footprints — which span several rock layers — suggested that people roamed there for two millennia between roughly 23,000 and 21,000 years ago (SN: 9/23/21). The result added to other evidence pushing back on a long-held theory that the first humans in North America came from Siberia via a land bridge sometime around 16,000 to 14,000 years ago.
"But some scientists noted that the aquatic plants used to date the footprints could have absorbed ancient carbon in groundwater, a well-known phenomenon. “There’s a potential then for the plant to give exaggerated perspectives on its age,” says Davis, who cowrote a critique of the 2021 paper.
"The criticism wasn’t surprising, says geologist Jeff Pigati of the U.S. Geological Survey’s Geosciences and Environmental Change Science Center in Denver. “We knew from the very beginning that we were going to have to independently evaluate the ages with different dating techniques.”
"To add to their past work, Pigati and colleagues radiocarbon-dated pollen stuck in the same layers as some of the footprints. The pollen came from land plants, primarily pine, spruce and fir trees, avoiding the groundwater carbon issue. The researchers also collected quartz grains above the lowest footprints and used a dating method that estimates how long the quartz had been buried.
"The pollen yielded an age range of roughly 23,400 to 22,600 years old, and the quartz gave an age minimum of about 21,500 years old. Both results echo the previous age estimate.
***
"Despite possible errors in the individual dating methods, “the data overall from the [new] study strongly indicate human presence in the Americas” around 22,000 years ago, Bente Philippsen, a physicist at the Norwegian University of Science and Technology in Trondheim, wrote in a commentary in the same issue of Science."
Comment: there have been some reports of earlier human activity in South America.
Human evolution: our heart differs from great apes
by David Turell , Sunday, August 25, 2024, 18:47 (88 days ago) @ David Turell
Theirs is trabeculated, ours not:
https://www.sciencealert.com/the-human-heart-is-unique-among-mammals-for-this-key-reason
"...it was believed until recently that the structure and function of the heart across mammals was the same. But research from my colleagues and I reveals that the human heart is an outlier, distinctly different from those of our closest relatives, the great apes, including chimpanzees, bonobos, orangutans and gorillas.
"So, why are humans the odd ones out?
"Humans diverged from chimpanzees (Pan Troglodytes), our last common ancestor, between five and six million years ago. In contrast, people evolved to stand upright to engage in greater amounts of activity, such as persistence hunting. And we have developed considerably larger brains.
"These changes to humans' bodies were associated with a much greater metabolic demand, requiring more blood to be pumped to our muscles and brain. Our research suggests that the human heart has adapted to support our upright stance, movement and larger brain.
***
"Our previous research has suggested that the structure of the human heart may be different to that of the chimpanzee. Using cardiac ultrasound, we discovered that the left ventricle – the heart's main pumping chamber – in chimpanzees contains bundles of muscles arranged in a mesh known as "trabeculations".
"For our current study, we wanted to examine if trabeculations exist in the other great apes, which we found that they do. In contrast, humans have a smooth wall of the left ventricle. This difference is especially pronounced at the bottom of the left ventricle, where the human heart's smoothness is nearly four times greater than that of our great ape relatives.
"Our research didn't just reveal structural differences in the human left ventricle compared to that of the great apes; we also uncovered a important difference in function. By using a specialized technique called "speckle-tracking echocardiography", which tracks heart muscle movement during contraction and relaxation, we examined how the muscle thickens, twists, rotates and lengthens.
"The results were striking. Humans, who have the least trabeculation, exhibited much greater twist and rotation at the apex (the tip of the heart) during contraction. In contrast, non-human great apes, with their heavily trabeculated hearts, showed much less movement.
"We believe the human heart evolved away from the trabeculated structure seen in the other great apes to enhance its ability to twist and contract more efficiently. This increased twisting motion, along with the smooth ventricular walls, probably allows the human heart to pump a larger volume of blood with each beat.
"This meets the heightened demands of our physical activity and larger brains.
"Our research challenges the assumption that heart structure is uniform across mammals. Instead, subtle but crucial differences in heart anatomy and function have emerged in response to unique environmental challenges."
Comment: the left ventricle is the key chamber pumping blood to the whole body. Cardiologists measure how much the left ventricle empties with each beat, normally 67-70 percent of total volume. The original paper did not show those results if performed. The key point is still made, we evolved away from other mammals because of our unusual mobility and exercise capacity.
Human evolution: geoglyphs in Peru
by David Turell , Monday, September 23, 2024, 22:59 (59 days ago) @ David Turell
Over 700 found now:
https://www.sciencealert.com/hundreds-of-mysterious-nazca-glyphs-have-just-been-revealed
In the desert of southern Peru, a mystery has been unfolding over decades.
Hundreds of years ago, the people who lived nearby carved the ground with giant lines to create pictures and symbols that can only be fully appreciated from the sky. These are the Nazca glyphs, mysterious designs whose purpose has baffled archaeologists ever since.
Since their first discovery in the 1940s, around 430 glyphs have been discovered on the arid plateau known as the Nazca Pampa.
Now, using drones and AI, a team led by archaeologist and anthropologist Masato Sakai of Yamagata University in Japan has discovered a jaw-dropping 303 more in just six months – nearly doubling the known number.
With the discovery comes new insight regarding the function of the mysterious symbols.
***
This purpose, the researchers believe, is sacred – designed as part of a pilgrimage to Cahuachi, the ceremonial center of the Nazca culture, which overlooks some of the glyphs from high perches atop mounds.
The glyphs have been difficult to uncover for several reasons. One of those is that they were first carved into the plateau between 500 BCE and 500 CE, and weathering over hundreds of years has greatly reduced their detectability.
Another obstacle is that the sheer size of the Nazca Pampa prohibits fieldwork on the ground. It's simply too huge a job.
"Because the Nazca Pampa is so vast, at 400 square kilometers (154 square miles), it takes a long time to conduct research using conventional archaeological methods," Sakai explained.
Since 2004, Sakai has been using remote sensing to explore the Nazca Pampa, and, prior to this new research, he and his colleagues over the years had discovered 318 of the 430 previously known glyphs.
Humans are therefore pretty good at spotting the telltale signs that reveal the faded, weathered symbols, but the researchers thought that AI might be able to identify signs of the Nazca that previous observations had missed.
So Sakai and his colleagues teamed up with the IBM Thomas J. Watson Research Center to develop an algorithm for identifying faint glyphs amid the rubble on the Nazca Pampa from drone images.
Of the 303 new glyphs, 178 – more than half – were suggested by the AI, revealing the power of this tool to assist in human-led research efforts.
***
"In the case of relief-type geoglyphs, you can see them if you walk along the trails. Therefore, I believe that the trails were created so that people could see the relief-type geoglyphs while walking along them," Sakai explained.
"On the other hand, in the case of line-type geoglyphs, they are concentrated around the starting and ending points of the network of linear geoglyphs. This network is connected to ceremonial centers Cahuachi and sacred places, so I believe that people walked along the network."
Cahuachi is known to be a site to which humans undertook pilgrimages, traveling to the adobe architectural complex, possibly for gatherings and ceremonies, although the exact ways in which the site was used, and why it was special, are poorly understood.
But there might be clues in the geoglyphs. Now, with more than 700 revealed to us, there may be some more concrete answers to be discovered. That is the big question Sakai hopes to tackle next.
"In the ancient Andean civilization, socially important information was sometimes conveyed through combinations and arrangements of pictures. I believe that information was inscribed on the Nazca Pampa through the arrangement and combination of geoglyphs," Sakai told ScienceAlert.
Comment: If you just see these words, you are missing the fun. The pictures are amazing.
Human evolution: early mammalian evolution
by David Turell , Wednesday, September 25, 2024, 20:04 (57 days ago) @ David Turell
New South American fossils:
https://www.sciencedaily.com/releases/2024/09/240925123653.htm
"These fossils, belonging to the mammal-precursor species Brasilodon quadrangularis and Riograndia guaibensis, offer critical insights into the development of the mammalian jaw and middle ear, revealing evolutionary experiments that occurred millions of years earlier than previously thought.
"Mammals stand out among vertebrates for their distinct jaw structure and the presence of three middle ear bones. This transition from earlier vertebrates, which had a single middle ear bone, has long fascinated scientists. The new study explores how mammal ancestors, known as cynodonts, evolved these features over time.
***
"These findings suggest that mammalian ancestors experimented with different jaw functions, leading to the evolution of 'mammalian' traits independently in various lineages. The early evolution of mammals, it turns out, was far more complex and varied than previously understood.
"Lead author James Rawson based in Bristol's School of Earth Sciences explained: "The acquisition of the mammalian jaw contact was a key moment in mammal evolution.
"What these new Brazilian fossils have shown is that different cynodont groups were experimenting with various jaw joint types, and that some features once considered uniquely mammalian evolved numerous times in other lineages as well."
"This discovery has broad implications for the understanding of the early stages of mammal evolution, illustrating that features such as the mammalian jaw joint and middle ear bones evolved in a patchwork, or mosaic, fashion across different cynodont groups.
"Dr. Agustín Martinelli, from the Museo Argentino de Ciencias Natural of Buenos Aires, stated: "Over the last years, these tiny fossil species from Brazil have brought marvellous information that enrich our knowledge about the origin and evolution of mammalian features. We are just in the beginning and our multi-national collaborations will bring more news soon.'"
Comment: mammals are very different unique branch of evolution that led to us. What was the natural necessity that drove these developments? There is none that is obvious. Still an evidence for design with purpose.
Human evolution: disappearance of Neanderthals
by David Turell , Monday, October 07, 2024, 14:56 (45 days ago) @ David Turell
Latest suppositions:
https://www.livescience.com/archaeology/did-we-kill-the-neanderthals-new-research-may-f...
About 37,000 years ago, Neanderthals clustered in small groups in what is now southern Spain. Their lives may have been transformed by the eruption of the Phlegraean Fields in Italy a few thousand years earlier, when the caldera's massive explosion disrupted food chains across the Mediterranean region.
***
By 34,000 years ago, our closest relatives had effectively gone extinct. But because modern humans and Neanderthals overlapped in time and space for thousands of years, archaeologists have long wondered whether our species wiped out our closest relatives. This may have occurred directly, such as through violence and warfare, or indirectly, through disease or competition for resources.
***
Decades of research has revealed a complex picture: A perfect storm of factors — including competition among Neanderthal groups, inbreeding and, yes, modern humans — helped erase our closest relatives from the planet.
***
Now, more than 150 years of archaeological and genetic evidence makes it clear that these early human relatives were much more advanced than we originally thought. Neanderthals crafted sophisticated tools, may have made art, decorated their bodies, buried their dead, and had advanced communication abilities, albeit a more primitive kind of language than modern humans used. What's more, they survived for hundreds of thousands of years in the hostile climates of Northern Europe and Siberia.
***
Based on archaeological evidence from sites from Russia to the Iberian Peninsula, Neanderthals and modern humans likely overlapped for at least 2,600 years — and perhaps as long as 7,000 years — in Europe. That overlap occurred during a bleak period in Neanderthal history that ended with their downfall — raising the question of whether modern humans were responsible for killing them off.
***
The first empirical proof of that interbreeding was found in 2010, when a Neanderthal genome was sequenced. Since then, genetic analysis has shown that Neanderthals and modern humans shared much more than a geographic area — we regularly exchanged DNA back and forth, meaning there is a bit of Neanderthal in every modern human population studied to date.
When modern humans and Neanderthals met tens of thousands of years ago, the latter were probably already in trouble. Genetic studies suggest that Neanderthals had lower genetic diversity and smaller group sizes than modern humans, hinting at a potential reason for Neanderthals' demise.
"Genetically, one big clue that we get is this idea of heterozygosity," Omer Gokcumen, an evolutionary genomicist at the University at Buffalo, told Live Science...In Neanderthals' small communities, which contained fewer than 20 adults in each group, more inbreeding occurred. That meant fewer of them inherited different versions of a gene from each parent and, therefore, had low heterozygosity.
"Neanderthals may have suffered for that — what they call a mutational burden," Gokcumen said. Genetic research suggests Neanderthals had many problematic mutations that likely affected their survival. "Because of their small population size, they couldn't actually breed these bad alleles out, and their kids may actually be sickly at the end," Gokcumen said.
***
while Neanderthal populations began decreasing until they became small, isolated groups without the social support necessary to care for their increasingly sickly babies, modern human groups quickly expanded through Europe.
***
Nor is there genetic evidence that modern humans' diseases killed off the Neanderthals, though we do share many immune-related genes. For instance, we inherited Neanderthal genes that make us susceptible to autoimmune disorders such as lupus and Crohn's disease as well as to severe COVID-19. Future genetic analyses may reveal the potential role of disease in Neanderthals' demise, Gokcumen said.
***
Neanderthal artifacts, such as pendants and etchings, show that Neanderthals were intelligent. But new research suggests there are significant differences between H. sapiens and Neanderthal brains: Modern humans have more neurons in brain regions key to higher-level thinking, and their neurons are more connected — meaning modern humans were likely more capable of thinking quickly. Combined with Neanderthals' greater difficulty in processing language, this could mean modern humans had an advantage in key tasks, Nowell said, such as hunting and foraging for food.
***
"Some Neanderthal populations died out, some got massacred, some interacted and some only exchanged ideas," Sang-Hee Lee, a biological anthropologist at the University of California, Riverside, told Live Science. "The really exciting questions like 'Why did Neanderthals disappear?' 'Why did they go extinct?' no longer can have one overarching theory" she said. "Neanderthals as a whole did not have a cohesive, shared fate."
Comment: the exact story is still unknown but the above guesswork is a good summary.
Human evolution: living in rougher places
by David Turell , Thursday, October 10, 2024, 15:48 (42 days ago) @ David Turell
edited by David Turell, Thursday, October 10, 2024, 15:53
Theory is it helped us develop well:
https://www.science.org/doi/10.1126/sciadv.adq3613?utm_source=sfmc&utm_medium=email...
"Abstract
Over the past 3 million years, humans have expanded their ecological niche and adapted to more diverse environments. The temporal evolution and underlying drivers behind this niche expansion remain largely unknown. By combining archeological findings with landscape topographic data and model simulations of the climate and biomes, we show that human sites clustered in areas with increased terrain roughness, corresponding to higher levels of biodiversity. We find a gradual increase in human habitat preferences toward rough terrains until about 1.1 million years ago (Ma), followed by a 300 thousand-year-long contraction of the ecological niche. This period coincided with the Mid-Pleistocene Transition [MPT] and previously hypothesized ancestral population bottlenecks. Our statistical analysis further reveals that from 0.8 Ma onward, the human niche expanded again, with human species (e.g., H. heidelbergensis, H. neanderthalensis, and H. sapiens) adapting to rougher terrain, colder and drier conditions, and toward regions of higher ecological diversity.
"DISCUSSION
The results shown here expand our understanding of the environmental factors that shaped hominin behavioral strategies and their evolutionary trajectories. Our analysis does not rely on the construction of an explicit environmental niche model; we simply analyze the climate and vegetation conditions and estimates of terrain roughness at previously reported sites of hominin presence. Our aggregated statistical analysis reveals that human species adapted to landscapes that were characterized by regionally increased biome diversity, as stipulated in the previously proposed Diversity Selection Hypothesis, and that this ecotone inclination was realized in particular in regions with higher terrain roughness. According to our analysis, area roughness is the most important predictor of human biome diversity at sites of hominin occupation, exceeding even the contributions of the key climatic variables temperature and precipitation. This result supports the notion that terrain roughness (slope) is an important predictor in hominin studies and niche modeling.
"Human adaptation toward increasing area roughness occurred in two major phases: The first one, from 2 to 1.1 Ma, was interrupted by a substantial decrease during the MPT. The second adaptation phase, 0.9 to 0.1 Ma, coincided with the expansion of H. heidelbergensis and H. neanderthalensis into Europe and the general positive trend in the brain size of hominins. The niche contraction during the MPT, which occurred mostly in Africa, coincided with several major evolutionary events. In Africa, recent studies suggest a human population bottleneck, which reportedly reduced the genomic diversity of humans by a factor of ~80. The timing also roughly matches with estimates of when the fusion of human chromosome 2 (found in Denisovans, Neanderthals, and H. sapiens) took place, although the dating uncertainties for this genomic transition still remain large. MPT climate variability might have also been a factor in the extinction of other genera and species, such as Paranthropus robustus. These different lines of evidence suggest that climatic and ecosystem changes during the MPT transition may have played a major role in hominin evolution.
"Even when categorizing hominins into groups based on their terrain roughness tolerance (low, medium, and high), we find that terrain roughness continues to be the dominant contributor to increased biome diversity across all groups relative to temperature and precipitation contributions. The areas with medium and high roughness are particularly abundant with diverse food resources, environmental niches, and potential natural shelters to mitigate weather and climate extremes. These characteristics may have contributed to the survival and overall evolution of the genus Homo, increasing their resilience and versatility.
***
"...our analysis agrees with other lines of independent evidence (18–20) that point to the importance of terrain roughness as a key factor in human habitat suitability regionally and on continental scales. Investigating the relationship between environmental heterogeneity, resource availability, and energy expenditure presents a promising avenue for future research."
Comment: our extraordinary abilities allowed this type of activity in diversity, and helped refine them as top predator as in this observation:
https://mail.google.com/mail/u/0/#inbox/FMfcgzQXJZtWljJpzVhNgPsHDwKjTXNx
"The authors suggest our ancestors sought uncomfortable habitats because “areas with medium and high roughness are particularly abundant with diverse food resources, environmental niches, and potential natural shelters to mitigate weather and climate extremes.” That may have meant traveling less for necessities, allowing ancient humans to devote “more time and resources to other activities, such as social interactions or tool production.” So ultimately, taking the road less traveled “may have contributed to the survival and overall evolution of the genus Homo.”
Human evolution: lots of interbreeding
by David Turell , Tuesday, October 15, 2024, 00:08 (38 days ago) @ David Turell
Human DNA is a mixture, not pure:
https://www.scientificamerican.com/article/human-origins-look-ever-more-tangled-with-ge...
"Only 200,000 years ago, our ancestors lived on a planet teeming with varied human relatives: Neandertals lived in Europe and the Middle East. Denisovans, known today only from bone fragments, teeth and DNA, dwelled across Asia and perhaps even in the Pacific. “Hobbits,” or Homo floresiensis, a diminutive species, lived in Indonesia, as another short-statured species, called Homo luzonensis, did in the Philippines. Even Homo erectus, the grandparent of early human species, was still running around as recently as 112,000 years ago.
"Now they are all gone. Except in our genes. Denisovans interbred with Neandertals, and both mated with modern humans. Genes from “an unknown hominin in Africa” also mark modern humans’ genomes. The initial discovery of these admixtures, starting in 2010, shook up the once-conventional “Out of Africa” picture of human origins, which saw a small, singular group of human ancestors developing language and then replacing all others worldwide within the last 100,000 years.
"Instead, the emerging picture of our origins is less of a family tree, and more of a tangled shrub, one whose winding branches wove distinct human groups together into today’s broader human population. People today largely derive from interbreeding between modern-looking humans in Africa and the disparate human populations littering the wider world. Those African expatriates themselves first arose from scattered, intermittently admixtured populations found across that continent.
***
"...with evidence hinting that Homo sapiens lived in Greece 210,000 years ago, then ceded Europe to Neandertals. Genetic studies suggest this gene-swapping peaked twice, at about 200,000 years ago and again 50,000 years ago. Even some of the bacteria in our mouths, ponder that, appear to have a Neandertal origin. Because of that early mixing, Neandertals themselves averaged 2.5 to 3.7 percent Homo sapiens DNA, a contribution that confused the family tree later.
***
"A similar picture of shuffled genes and small populations is shaping up for Denisovans and other archaic human species. All this genetic shuffling leaves humanity itself looking like a bit of a mess. A July 2021 analysis for example found that “only 1.5 to 7 [percent] of the modern human genome is uniquely human.”
"That’s not a lot. In a review of humanity’s scattered genetic history, scientists, including Chris Stringer of the Natural History Museum in London, once a champion of a strict Out of Africa view of human origins, looked over the patchwork of human and archaic fossils and genes. Stringer and colleagues concluded in Nature in 2021 that “no specific point in time can currently be identified at which modern human ancestry was confined to a limited birthplace.”
"Our origin therefore does not appear to be a particularly tidy one, but a complex one that involved a lot of mating across time and space. We weren’t so much conquerors as wanderers, and potential in-laws, in our new neighborhoods. Something to consider the next time you hear someone going on about their family history, or how other people are unwanted outsiders."
Comment: Not a surprising conclusion. Each sob-group contributed useful genetic attributes such as the well-known immunity contribution from the Neanderthals. A designer might have done this to make His work simpler, with each group supplying useful attributes from their environmental experiences.
Human evolution: Australopithecus hand use
by David Turell , Tuesday, October 15, 2024, 20:32 (37 days ago) @ David Turell
Very advanced looking:
https://phys.org/news/2024-10-ancient-hominins-humanlike-indicating-earlier.html
"An analysis by Eberhard Karls University of Tübingen, Germany, on the manual capabilities of early hominins reveals that some Australopithecus species exhibited hand use similar to modern humans.
"In demonstrating that certain Australopithecus species possessed hand anatomies conducive to tool use, the study suggests that tool use may have originated much earlier than previously documented.
***
"According to the study, muscle attachment sites are crucial to understanding the functional use of hands through biomechanical loading. The method allows for a more profound reconstruction of habitual activities and manual behaviors, allowing us to see the effects of sustained tool use in the biomechanics of the hands and, from this, learn a great deal about how the tool might have been used.
"The study utilized three-dimensional models of the hand bones to investigate the biomechanics in detail. Muscle attachment areas were identified based on differences in bone surface elevation, coloration (when available), and surface complexity. The identified areas were carefully outlined to separate muscle attachment sites from the rest of the bone.
"Findings indicate that A. sediba and A. afarensis possessed patterns of muscle attachment that suggest they possessed the anatomical foundation for manipulation activities similar to those of humans. This implies that these species engaged in tasks such as power grasping and in-hand object manipulation essential for tool use.
"A. africanus displayed a combination of attachment features, indicating both human and apelike hand use. This mosaic pattern suggests a versatility in manual behaviors, potentially influenced by tool-related activities.
"The frequent activation of muscles needed to perform characteristic humanlike grasping and manipulation in these early hominins lends support to the notion that humanlike hand use emerged prior to, and likely influenced, the evolutionary adaptations for higher manual dexterity in later hominins," the researchers state in their paper.
***
"Australopithecus afarensis lived approximately 3.9 to 3 million years ago and was found primarily in East Africa. They were able to walk on two legs while retaining some typical tree climbing features. The braincase was on the smaller side with a prominent brow ridge and more ape-like facial features than the others. The group is well-represented by "Lucy," one of the most complete and well-preserved A. afarensis skeletons ever discovered and possibly the world's most famous anthropological celebrity.
"Australopithecus africanus lived approximately 3.3 to 2 million years ago, primarily discovered in South Africa. Also bipedal and adapted for both walking upright and climbing, the hominins had longer arms relative to legs compared to later Homo species. The braincase was larger than A. afarensis, with a more rounded skull. They possessed smaller molars and larger canines, indicating a varied diet of tough vegetation and softer foods. They are one of the most successful hominins in terms of longevity in a persistent form (four times longer than current modern humans have been around).
"Australopithecus sediba lived approximately 2 to 1.8 million years ago and were discovered in the Malapa region of South Africa. They were also bipedal and retained climbing ability. They had a slightly larger braincase than earlier Australopithecus species."
Comment: tool use is very important for survival. Early design of useful hands is a reasonable way for a designer to plan the evolution of newer forms.
Human evolution: more on Morocco fossils from 315,000 ya
by David Turell , Tuesday, October 29, 2024, 15:59 (23 days ago) @ David Turell
From ~315,000 years ago:
https://www.nationalgeographic.com/history/article/morocco-early-human-fossils-anthropo...
"Now, examinations of fire-baked tools from the site suggest that these ancient people lived more than 300,000 years ago, making them twice as old as previously thought.
"The findings, announced in Nature on Wednesday, fill a crucial gap in the human fossil record. That’s because these people bear many striking similarities to modern humans even though they lived well before what may be the oldest fossil evidence of Homo sapiens, from a site in Ethiopia dated to about 195,000 years ago.
"The residents of the Moroccan site weren’t quite the Homo sapiens of today; their skulls were less rounded and more elongated than ours, perhaps signaling differences between our brains and theirs. However, their teeth closely resemble those in the mouths of modern humans—and their faces looked just like ours.
***
"What’s more, the Moroccan site is in northwest Africa, far from the sites in East and South Africa that have yielded many of Africa’s other hominin fossils.
"To paleoanthropologists, the combination of this site’s age and location serve as a powerful reminder that the evolution of modern humans was likely more ancient, and more dispersed across Africa, than previous discoveries suggested.
***
"The Moroccan site, known as Jebel Irhoud, was an active barite mine when it first made scientific waves in the 1960s. Digging yielded stone tools and some enigmatic skull fragments, which scientists initially assigned to an ancient relative of modern humans.
***
"To researchers’ delight, a piece of the archaeological site survived under the mining rubble—and it yielded more stone tools, ample evidence of humans using fire, and some skeletal remains, including a lower jaw and part of a braincase.
"Importantly, finding the stone tools and skeletal remains in the same rock layer meant that Hublin’s team could use the tools to more accurately date the Jebel Irhoud fossils.
"The team took advantage of the fact that the stone tools had been scattered around and inadvertently heated by the Jebel Irhoud humans’ campfires. Heating the stone tools zeroed out the electrical charge they had been carrying. That means any charge in the tools today would have been generated after they were buried, as the surrounding sediments bombarded the stone with natural radioactivity.
"Hublin’s team spent a year measuring the radioactivity of the Jebel Irhoud site. By comparing this annual radiation dose to the tools’ current electrical charge, the team determined that the Jebel Irhoud campfires baked the tools about 315,000 years ago, give or take 34,000 years. (my bold)
***
"Jebel Irhoud’s dates overlap with the dates recently ascribed to Homo naledi, an extinct—and anatomically bizarre—hominin species discovered in South Africa. The find provides further evidence that at least two dramatically different species of hominins occupied Africa at the same time.
"Given the Jebel Irhoud fossils’ modern faces and primitive braincases, Hublin and his team suggest that the features associated with modern humans probably didn’t evolve all at once. Instead, various traits we associate with anatomically modern humans probably appeared in a type of “mosaic evolution” that Neanderthals also seem to have exhibited.
"Modern humankind “wasn’t a new model of an automobile that appeared in a showroom with all the bells and whistles,” says Wood. “Different parts of modern human morphology and behavior probably came incrementally.”
"The find also shows how the precursors to modern humans could have dispersed widely across Africa, Hublin’s team says. For instance, perhaps they spread into northern Africa during periodic “green Sahara” events, when the forbidding desert sometimes gave way to more hospitable grassland.
"However, Hublin and his coauthor Shannon McPherron emphasize that they cannot yet say precisely where modern humans evolved on the continent.
"In addition, the finds present an intriguing dilemma: Should paleoanthropologists treat the Jebel Irhoud remains as part of the Homo sapiens species?
***
"While Hawks applauds the researchers for their careful re-excavations, he also cautions against overplaying the papers’ significance.
“Many scientists have noted the very archaic features of the [Jebel Irhoud] braincase, and some more similarities with modern humans in the face,” he adds by email. Hublin and his colleagues “really aren’t adding anything new except the date.”
"For Wood, though, Hublin’s use of “early modern humans” makes sense. And regardless of precise labels, he says, the Jebel Irhoud fossils have their place in the tapestry of humankind.
“'Three hundred thousand years ago, there is fossil evidence of a population that in a remarkable number of ways resembles modern humans, and you can make of that what you like,” says Wood.
“'You can either expand the definition of Homo sapiens to include [Jebel Irhoud], or these were creatures that were on their way to [becoming] modern humans.'”
Comment: An earlier report was presented here giving the 315,000 year's ago dating, with the statement the fossils were H sapiens. They certainly were 'almost' our level of development.
Human evolution: vagus nerve, liver and urge to eat
by David Turell , Friday, November 08, 2024, 17:53 (13 days ago) @ David Turell
As noted before, the vagus nerve is in control of liver hunger stimulation:
https://www.sciencemagazinedigital.org/sciencemagazine/library/item/08_november_2024/42...
"The hepatic vagal nerve mediates the impact of circadian disruption on food intake in mice
"Timing mechanisms have evolved across all kingdoms of life to anticipate daily changes in the light environment and to optimize opportunities for nutrition. In mammals, the central circadian clock in the hypothalamic suprachiasmatic nucleus synchronizes to external light. However, other cells, tissues, and organs in the body have their own circadian clocks. For example, the liver has a molecular clock that can be entrained by feeding-fasting cycles. Desynchrony between the light-entrained suprachiasmatic nucleus and the food-entrained liver carries adverse health consequences, including increased risk of cardiometabolic diseases or type 2 diabetes; yet, how these clocks become misaligned remains unknown. On page 673 of this issue, Woodie et al. report a neural link from the liver to the brain that conveys the misalignment signal to drive changes in eating behavior, body weight maintenance, and energy metabolism. This reveals a potential therapeutic target to mitigate the metabolic impact of circadian disruption.
"Mammalian circadian rhythms are set by cues that initiate a transcription-translation feedback loop involving activators [such as BMAL1 (basic helix-loop-helix ARNT-like protein 1)] and repressors [such as REV-ERBs (reverse c-erbAa)]. Deletion of the core clock components REV-ERBα and REV-ERBβ in adult mouse hepatocytes disrupts circadian changes in gene expression and liver function.
***
"Food intake is regulated by a complex central neuronal system, primarily involving hypothalamic centers located at the base of the brain. Of particular importance is the arcuate nucleus of the hypothalamus, which has a key role in controlling food intake. Indeed, in mice lacking REV-ERBα and REV-ERBβ in liver cells, the circadian organization of the arcuate nucleus in the hypothalamus was disrupted, confirming that rhythmic activity in this important feeding center requires a rhythmic liver.
"The central metabolic circuitry is regulated by numerous endocrine and neural inputs. The common hepatic branch of the vagus nerve is a two-way highway of communication between the brain and liver, regulating many aspects of food intake and metabolism. Fibers in this region transmit information on liver function to the brain.
***
"This finding supports the hypothesis that afferent vagal signaling is a key mediator for the desynchronized liver clock. It also underscores the vital role of the liver-brain axis, which requires an intact hepatic vagus nerve, a pathway previously shown to be crucial in controlling metabolic functions, such as glucose homeostasis.
***
"Notably, transection of the hepatic vagal branch reduced calorie intake to that observed during the animal’s active phase, reduced overall calorie intake, and prevented the development of obesity. This intervention provides a mechanistic explanation for the experimentally observed beneficial effects of timerestricted feeding in mice and time-restricted eating in people.
***
"The implication of the findings of Woodie et al. is that the circadian-disrupted liver sends signals to the arcuate nucleus to drive disordered eating and that this circuit explains the obesity seen in response to prevalent human circadian and sleep disruption (such as shift work)."
Comment: here we see a highly complex control of appetite. The purpose is proper weight control. Darwin style 'natural' evolution has no purpose. So how did this happen? This is obviously designed.
Human evolution: Denisovan contribution
by David Turell , Saturday, November 09, 2024, 19:27 (12 days ago) @ David Turell
Three major events:
https://phys.org/news/2024-11-insights-denisovans-hominin-group-interbred.html
"'It's a common misconception that humans evolved suddenly and neatly from one common ancestor, but the more we learn the more we realize interbreeding with different hominins occurred and helped to shape the people we are today.
"'Unlike Neanderthal remains, the Denisovan fossil record consists of only that finger bone, a jawbone, teeth, and skull fragments. But by leveraging the surviving Denisovan segments in Modern Human genomes, scientists have uncovered evidence of at least three past events whereby genes from distinct Denisovan populations made their way into the genetic signatures of modern humans."
"Each of these presents different levels of relatedness to the sequenced Altai Denisovan, indicating a complex relationship between these sister lineages.
"In the review article, Dr. Ongaro and Prof. Emilia Huerta-Sanchez outline evidence suggesting that several Denisovan populations, who likely had an extensive geographical range from Siberia to Southeast Asia and from Oceania to South America, were adapted to distinct environments.
"They further outline a number of genes of Denisovan origin that gave modern day humans advantages in their different environments.
"Dr. Ongaro added, "Among these is a genetic locus that confers a tolerance to hypoxia, or low oxygen conditions, which makes a lot of sense, as it is seen in Tibetan populations; multiple genes that confer heightened immunity; and one that impacts lipid metabolism, providing heat when stimulated by cold, which confers an advantage to Inuit populations in the Arctic."
Comment: we are an amalgam of several varieties of HOMO forms which contributed differences based upon their climate of origin. God might have thought this might be the perfect way to create the best final design. To ask why God did not directly do it brings us back to the question of why He used evolution instead of direct creation.
Human evolution: Denisovan contribution
QUOTE: "In the review article, Dr. Ongaro and Prof. Emilia Huerta-Sanchez outline evidence suggesting that several Denisovan populations, who likely had an extensive geographical range from Siberia to Southeast Asia and from Oceania to South America, were adapted to distinct environments."
DAVID: we are an amalgam of several varieties of HOMO forms which contributed differences based upon their climate of origin. God might have thought this might be the perfect way to create the best final design. To ask why God did not directly do it brings us back to the question of why He used evolution instead of direct creation.
All these varieties confirm the theory that evolution develops as a result of cells adapting to or exploiting different environments. You can’t answer your own question if you insist that H. sapiens was your omnipotent, omniscient God’s one and only purpose. It simply doesn’t make sense. But if God exists, the whole of evolution makes perfect sense if he planned a free-for-all through cellular autonomy (with the option of dabbling if he wanted to), or if he was deliberately experimenting with different forms in order to make new discoveries, or in order to find a particular formula (e.g. for a being “in his own image”, which is your view of his purpose). And of course evolution also makes perfect sense if you believe that the first cells miraculously assembled themselves by chance and proceeded to create the free-for-all of species that come and then go or are lucky enough (Raup) to stay because of their ability to survive the changing conditions.
Human evolution: Denisovan contribution
by David Turell , Sunday, November 10, 2024, 19:00 (11 days ago) @ dhw
QUOTE: "In the review article, Dr. Ongaro and Prof. Emilia Huerta-Sanchez outline evidence suggesting that several Denisovan populations, who likely had an extensive geographical range from Siberia to Southeast Asia and from Oceania to South America, were adapted to distinct environments."
DAVID: we are an amalgam of several varieties of HOMO forms which contributed differences based upon their climate of origin. God might have thought this might be the perfect way to create the best final design. To ask why God did not directly do it brings us back to the question of why He used evolution instead of direct creation.
dhw: All these varieties confirm the theory that evolution develops as a result of cells adapting to or exploiting different environments. You can’t answer your own question if you insist that H. sapiens was your omnipotent, omniscient God’s one and only purpose. It simply doesn’t make sense. But if God exists, the whole of evolution makes perfect sense if he planned a free-for-all through cellular autonomy (with the option of dabbling if he wanted to), or if he was deliberately experimenting with different forms in order to make new discoveries, or in order to find a particular formula (e.g. for a being “in his own image”, which is your view of his purpose). And of course evolution also makes perfect sense if you believe that the first cells miraculously assembled themselves by chance and proceeded to create the free-for-all of species that come and then go or are lucky enough (Raup) to stay because of their ability to survive the changing conditions.
I view God as a mind at work. He knows all and can do anything He wishes. He evolved humans for His own reasons, at which we must guess. All of them have been exposed in the past here and I believe they represent human wishes about/for God. A natural free-for-all would not necessarily produce the human brain. As a most unusual result, it is a perfect object to use as a proof of God, as Adler did. dhw, as usual, finds reasons to avoid God in a direct way.
Human evolution: Denisovan contribution
QUOTE: "In the review article, Dr. Ongaro and Prof. Emilia Huerta-Sanchez outline evidence suggesting that several Denisovan populations, who likely had an extensive geographical range from Siberia to Southeast Asia and from Oceania to South America, were adapted to distinct environments."
DAVID: we are an amalgam of several varieties of HOMO forms which contributed differences based upon their climate of origin. God might have thought this might be the perfect way to create the best final design. To ask why God did not directly do it brings us back to the question of why He used evolution instead of direct creation.
dhw: All these varieties confirm the theory that evolution develops as a result of cells adapting to or exploiting different environments. You can’t answer your own question if you insist that H. sapiens was your omnipotent, omniscient God’s one and only purpose. It simply doesn’t make sense. But if God exists, the whole of evolution makes perfect sense if he planned a free-for-all through cellular autonomy (with the option of dabbling if he wanted to), or if he was deliberately experimenting with different forms in order to make new discoveries, or in order to find a particular formula (e.g. for a being “in his own image”, which is your view of his purpose). And of course evolution also makes perfect sense if you believe that the first cells miraculously assembled themselves by chance and proceeded to create the free-for-all of species that come and then go or are lucky enough (Raup) to stay because of their ability to survive the changing conditions.
DAVID: I view God as a mind at work. He knows all and can do anything He wishes.
If God exists, then I would find this feasible. That is why I have argued that he could have created an Eden (a world without evil) if he had wished, but you insist that he had no choice.
DAVID: He evolved humans for His own reasons, at which we must guess.
According to you he also designed every other species for His own reasons, and had to cull 99.9% of them because they were irrelevant to his one and only purpose. And you can’t even think of a single reason for this procedure, which is why you slate your God as an inefficient, messy, cumbersome designer.
DAVID: All of them have been exposed in the past here and I believe they represent human wishes about/for God.
You have propose that your God wanted to create us in order that we should recognize him and worship him. That would be his wish, not ours.
DAVID: A natural free-for-all would not necessarily produce the human brain.
Very true. A natural free-for-all would not necessarily have produced dinosaurs, whales, ants or the duck-billed platypus either. Your God may have dabbled, or he may have been delighted at all the different, unexpected products of his invention.
DAVID: As a most unusual result, it is a perfect object to use as a proof of God, as Adler did. dhw, as usual, finds reasons to avoid God in a direct way.
According to some ID-ers, the complexities of all life are enough to prove God’s existence. As for me, I have just offered you no less than three logical THEISTIC alternatives to your own totally irrational version of your God’s evolutionary purpose and method. For good measure, I added the atheist alternative. Stop pretending that my theistic alternatives “avoid” God. They avoid the insult that you throw at your God with your insistence that only you know his purpose and his inexplicably inefficient method of achieving the purpose you impose on him.
Human evolution: Denisovan contribution
by David Turell , Monday, November 11, 2024, 17:59 (10 days ago) @ dhw
DAVID: I view God as a mind at work. He knows all and can do anything He wishes.
dhw: If God exists, then I would find this feasible. That is why I have argued that he could have created an Eden (a world without evil) if he had wished, but you insist that he had no choice.
Of course no choice. All animals have to eat and they eat each other,
DAVID: He evolved humans for His own reasons, at which we must guess.dhw: According to you he also designed every other species for His own reasons, and had to cull 99.9% of them because they were irrelevant to his one and only purpose. And you can’t even think of a single reason for this procedure, which is why you slate your God as an inefficient, messy, cumbersome designer.
I can't solve the conundrum of why God evolved us. He hasn't ever revealed His reasoning.
DAVID: All of them have been exposed in the past here and I believe they represent human wishes about/for God.dhw: You have propose that your God wanted to create us in order that we should recognize him and worship him. That would be his wish, not ours.
Yes, but really our wish applied to Him.
DAVID: A natural free-for-all would not necessarily produce the human brain.dhw: Very true. A natural free-for-all would not necessarily have produced dinosaurs, whales, ants or the duck-billed platypus either. Your God may have dabbled, or he may have been delighted at all the different, unexpected products of his invention.
An omniscient God expects all events. Stop humanizing God.
DAVID: As a most unusual result, it is a perfect object to use as a proof of God, as Adler did. dhw, as usual, finds reasons to avoid God in a direct way.dhw: According to some ID-ers, the complexities of all life are enough to prove God’s existence. As for me, I have just offered you no less than three logical THEISTIC alternatives to your own totally irrational version of your God’s evolutionary purpose and method. For good measure, I added the atheist alternative. Stop pretending that my theistic alternatives “avoid” God. They avoid the insult that you throw at your God with your insistence that only you know his purpose and his inexplicably inefficient method of achieving the purpose you impose on him.
I've imposed nothing on God as you shape Him to conform to your image. I assume the universe and the evolution of life are a result of God's creations. Why He used evolution rather than direct creation is an unsolved question.
Human evolution: new discoveries in footprints
by David Turell , Monday, November 18, 2024, 22:17 (3 days ago) @ David Turell
In South Africa:
https://phys.org/news/2024-11-fossil-footprints-south-africa-coast.html
"I am an ichnologist. In 2008 my colleagues and I launched the Cape South Coast Ichnology Project to study a 350km stretch of South Africa's coastline. We've since identified more than 350 vertebrate tracksites, most of them in cemented dunes called aeolianites that date back to the Pleistocene Epoch (also known as the Ice Age), which began about 2.6 million years ago and ended 11,700 years ago.
"At a global level it is rare to find fossilized hominin tracks. There is something very special about them: a fossil trackway looks as if it could have been created yesterday, and the fact that our own ancestors would have created such tracks fills them with extra meaning. It's always a thrill for researchers to find them.
***
"Each site within this 1,200 meter stretch of coastline is from a different rock unit and they appear to span a considerable time interval. Adjacent rocks have been dated using a technique known as optically stimulated luminescence to a range of between 113,000 and 76,000 years (that is a measure of how long ago grains deep within the rocks were exposed to light).
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"Three of the Brenton-on-Sea sites also contain some of the oldest known evidence of humans using sticks. The organic matter from which such sticks were composed would long since have decayed, and the ichnology (trace fossil) record therefore provides what is probably the only viable means of identifying such stick use.
"Sticks could potentially have been used as walking or running aids, to cope with ambulating with an injury, in foraging techniques, for messaging, or for what might be aesthetic purposes, such as inscribing patterns in the sand.
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"Together, the sites containing these hominin tracks and traces provide complementary evidence not just of a human presence through footprints, but also of the behavior of our ancestors, providing details of their activities, their tools and their diet.
"They confirm the importance of the Cape coast as a region of great importance in the evolution of Homo sapiens prior to the subsequent diaspora out of Africa. The great preponderance of hominin tracksites older than 50,000 years has now been documented from South Africa's Cape coast, and a cluster of seven tracksites, like the one we have described, is extremely unusual globally."
Commwnt: H. Sapiens were active all over Africa . This adds to the most southern region.