More miscellany Parts One & Two (Evolution)

by dhw, Saturday, September 14, 2024, 09:43 (68 days ago) @ David Turell

Black holes needed for life

DAVID: Design is obvious. A designer is very feasible.

dhw: Agreed. But although that feasibly solves the mystery of life’s origin, it creates a different mystery: how – if for example our consciousness requires design – can a supreme form of consciousness exist without having been designed?

DAVID: Eternal mind never designed.

dhw: Consciousness requires design, but a supreme consciousness does not require design. Please explain the logic.

DAVID: Where is your logic of a necessary first cause?

For the umpteenth time, the choice is between an eternal, sourceless conscious mind and virtually infinite combinations of matter and energy which eventually chance to produce the first primitive forms of life and intelligence. Close your eyes and jump one way or the other, or admit that we just don’t know. Meanwhile, please explain your logic, as requested in bold.

Kamikaze termites

DAVID: You don't understand that ecosystems support all life?

dhw: All life is supported by ecosystems, but that does not mean that all ecosystems from the year dot, up to and including current ecosystems, have been designed exclusively to support humans and our food!

Bipedalism and savannahs

dhw; [..] I propose that at some time in the distant past, local conditions forced tree-dwellers out of their trees. There is no reason why the descendants of those successful bipedal hominids should not have gone on to explore and live in other environments, including forests. They would have gone wherever they could make a living!

DAVID: All true.

DAVID: Certainly, not an isolated event in one forest/greenland area. Many hominins gradually developed upright posture simultaneously.

That means convergent evolution. Perfectly feasible.

Two Neanderthal types

QUOTE: […] "an adult male’s partial skeleton discovered in France contains genetic clues to a Neanderthal line that evolved apart from other European Neanderthals for around 50,000 years."

dhw: Sensational new fossils are being discovered almost monthly, throwing doubt on established theories. Who knows what revolutionary discoveries might be made in, say, the next thousand years?

DAVID: It won't close existing gaps.

dhw: How do you know?

DAVID: Gaps are well established even if you wish they weren't. Remember Gould's quote.

Of course there will always be gaps! Who expects to find fossils covering every stage of every species for the last 3.8 billion years? I don’t wish anything. I simply look for convincing explanations of the history we know. Which Gould quote? I find his theory of punctuated equilibrium absolutely convincing.

Recent new modifications

DAVID: 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.

Once again,I must thank you for your integrity in presenting POSSIBLE evidence for a theory of which you disapprove. There are many crystal clear examples of adaptation, but the distinction between adaptation and innovation is sometimes blurred. Pre-whales and pre-humans might be taken as prime examples. Although we agree that speciation is still an unknown process, the very fact that DNA can be edited is a major plus for Shapiro’s theory: if cells are capable of editing their own DNA, where and why do you draw a limit?

Dinosaurs to birds

QUOTES: Alan Feduccia […] convincingly argues that all those feathered bipedal “dinosaurs” are in fact not related to theropod dinosaurs at all but rather represent secondarily flightless birds.
"There are clearly open questions and it definitely looks like the common dino-to-bird narrative has been massively oversold to the public and represents a theory with numerous holes and problems."

DAVID: this article calls into question dhw's assertion that 696 dinosaur species produced four bird types.

It’s not MY assertion, but the common theory that birds descended from theropods, of which there were four species, and that 696 dinosaur species produced no birds and no ancestors of any existing species. This article challenges the hitherto established theory, but offers no evidence whatsoever for your theory that 99.9 of all the creatures that ever lived were the ancestors of the current 0.1%. Do you really believe now that 696 dinosaur species were our ancestors?