Sticking a fork in Natural Selection (Introduction)
by David Turell , Monday, December 05, 2011, 15:41 (4715 days ago)
Excellent review with many editorial overtones on "What Darwin Got Wrong":
http://www.newoxfordreview.org/reviews.jsp?did=1111-scambray
Passive, passive, passive to the nth power.
Sticking a fork in Natural Selection
by xeno6696 , Sonoran Desert, Tuesday, December 06, 2011, 03:04 (4715 days ago) @ David Turell
Excellent review with many editorial overtones on "What Darwin Got Wrong":
http://www.newoxfordreview.org/reviews.jsp?did=1111-scambray
Passive, passive, passive to the nth power.
There is one and only one definitive test that would permanently displace Natural Selection:
An species that emerges without a corresponding stimulus from environment.
Until that happens--Fedor's philosophy is an opium dream.
--
\"Why is it, Master, that ascetics fight with ascetics?\"
\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"
Sticking a fork in Natural Selection
by David Turell , Tuesday, December 06, 2011, 05:25 (4715 days ago) @ xeno6696
Excellent review with many editorial overtones on "What Darwin Got Wrong":
http://www.newoxfordreview.org/reviews.jsp?did=1111-scambray
Passive, passive, passive to the nth power.
There is one and only one definitive test that would permanently displace Natural Selection:An species that emerges without a corresponding stimulus from environment.
Whoa!! We have no idea HOW NEW SPECIES EMERGE! All fossils show is sudden emergence, and don't remind me of Dawkins' whales. Each step is a sudden jump. Tell me how the Cambrian occurred.
Sticking a fork in Natural Selection
by xeno6696 , Sonoran Desert, Tuesday, December 06, 2011, 21:51 (4714 days ago) @ David Turell
Excellent review with many editorial overtones on "What Darwin Got Wrong":
http://www.newoxfordreview.org/reviews.jsp?did=1111-scambray
Passive, passive, passive to the nth power.
There is one and only one definitive test that would permanently displace Natural Selection:An species that emerges without a corresponding stimulus from environment.
Whoa!! We have no idea HOW NEW SPECIES EMERGE! All fossils show is sudden emergence, and don't remind me of Dawkins' whales. Each step is a sudden jump. Tell me how the Cambrian occurred.
The problem here is that whenever you bring this up... please define a sudden jump, and then explain how the "snapshot" observation of the fossil record is false... because to me, Evolution has always been something that could speed up and slow down based on need, so I don't see where the Cambrian Explosion really, fully, argues against the traditional view of evolution. You seem to be arguing that because we don't have a complete record of every successive form (and why would we?) then that is sufficient to make a case for some kind of "spontaneous" appearance. You don't have a case for that. You have a case for the fact that we lack successive forms. And then look at Horses... for God's sake, why would we assume that the natural progression of horses is any different than that of the Cambrian?
You make a good case for skepticism, but you fail to take it beyond that--and skepticism isn't enough to dislodge theories.
--
\"Why is it, Master, that ascetics fight with ascetics?\"
\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"
Sticking a fork in Natural Selection
by David Turell , Tuesday, December 06, 2011, 23:19 (4714 days ago) @ xeno6696
The problem here is that whenever you bring this up... please define a sudden jump, and then explain how the "snapshot" observation of the fossil record is false... because to me, Evolution has always been something that could speed up and slow down based on need, so I don't see where the Cambrian Explosion really, fully, argues against the traditional view of evolution.
Gould himself, to paraphrase, noted the jumps as a dark paleontologic secrets. The Cambrian is a huge jump. These animals have organ systems and eyes. Legs, very complete nervous systems. There is nothing before this that comes close. There is no gradual approach to the Cambrian. It comes out of nowhere and everything present now is based on it and on the later plant bloom. It is gradual from then on.
Sticking a fork in Natural Selection
by xeno6696 , Sonoran Desert, Wednesday, December 07, 2011, 03:18 (4714 days ago) @ David Turell
The problem here is that whenever you bring this up... please define a sudden jump, and then explain how the "snapshot" observation of the fossil record is false... because to me, Evolution has always been something that could speed up and slow down based on need, so I don't see where the Cambrian Explosion really, fully, argues against the traditional view of evolution.
Gould himself, to paraphrase, noted the jumps as a dark paleontologic secrets. The Cambrian is a huge jump. These animals have organ systems and eyes. Legs, very complete nervous systems. There is nothing before this that comes close. There is no gradual approach to the Cambrian. It comes out of nowhere and everything present now is based on it and on the later plant bloom. It is gradual from then on.
But you still dodge the question. There's plenty of good reasons that we lack transitions from pre-cambrian to cambrian. The snapshot view of the fossil record *underlines* this. What right do we have to expect that the fossil record will conform to our expecations?
--
\"Why is it, Master, that ascetics fight with ascetics?\"
\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"
Sticking a fork in Natural Selection
by David Turell , Wednesday, December 07, 2011, 05:36 (4714 days ago) @ xeno6696
But you still dodge the question. There's plenty of good reasons that we lack transitions from pre-cambrian to cambrian. The snapshot view of the fossil record *underlines* this. What right do we have to expect that the fossil record will conform to our expecations?
I'm not dodging anything. Give me some good reasons for the gap. And is a monster developmental gap from Edicarans and Bilatarians. And the Cambrian is not a one-shot wonder as gould presented. It is now found all over the world in Cambrian shale.
Sticking a fork in Natural Selection
by xeno6696 , Sonoran Desert, Wednesday, December 07, 2011, 13:35 (4713 days ago) @ David Turell
But you still dodge the question. There's plenty of good reasons that we lack transitions from pre-cambrian to cambrian. The snapshot view of the fossil record *underlines* this. What right do we have to expect that the fossil record will conform to our expecations?
I'm not dodging anything. Give me some good reasons for the gap. And is a monster developmental gap from Edicarans and Bilatarians. And the Cambrian is not a one-shot wonder as gould presented. It is now found all over the world in Cambrian shale.
The question I'm asking, is why don't you consider that the gaps in the record are explained by the fact we haven't found those fossils, for whatever reason. (ie, too soft, etc.) this is of course the first explanation i go to when the gap discussion appears.
--
\"Why is it, Master, that ascetics fight with ascetics?\"
\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"
Sticking a fork in Natural Selection
by David Turell , Wednesday, December 07, 2011, 15:15 (4713 days ago) @ xeno6696
But you still dodge the question. There's plenty of good reasons that we lack transitions from pre-cambrian to cambrian. The snapshot view of the fossil record *underlines* this. What right do we have to expect that the fossil record will conform to our expecations?
I'm not dodging anything. Give me some good reasons for the gap. And is a monster developmental gap from Edicarans and Bilatarians. And the Cambrian is not a one-shot wonder as gould presented. It is now found all over the world in Cambrian shale.
The question I'm asking, is why don't you consider that the gaps in the record are explained by the fact we haven't found those fossils, for whatever reason. (ie, too soft, etc.) this is of course the first explanation i go to when the gap discussion appears.
You are doing a 'Darwin'. He was troubled by the gaps and expected them to be closed. There are some very persistent gaps in time and form. what would you say if they never closed?
Sticking a fork in Natural Selection
by xeno6696 , Sonoran Desert, Wednesday, December 07, 2011, 16:02 (4713 days ago) @ David Turell
Absence of evidence is not evidence of absence —it’s a lack of evidence. I would say the same thing then that I have said before: We don’t have enough evidence to come to a conclusion. Our knowledge would be incomplete. I ask the question again, how is the snapshot view of the fossil record false? What reason(s) do we have to accept that for a few instances in history, everything we know about life mysteriously suspended and some other process took over, other than the traditional stimulus-response nature of evolution? How is the idea wrong that the reason that the gaps are there are because we simply haven’t been lucky enough to find these transient forms?
--
\"Why is it, Master, that ascetics fight with ascetics?\"
\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"
Sticking a fork in Natural Selection
by David Turell , Wednesday, December 07, 2011, 16:46 (4713 days ago) @ xeno6696
Absence of evidence is not evidence of absence —it’s a lack of evidence. I would say the same thing then that I have said before: We don’t have enough evidence to come to a conclusion. Our knowledge would be incomplete. I ask the question again, how is the snapshot view of the fossil record false? What reason(s) do we have to accept that for a few instances in history, everything we know about life mysteriously suspended and some other process took over, other than the traditional stimulus-response nature of evolution? How is the idea wrong that the reason that the gaps are there are because we simply haven’t been lucky enough to find these transient forms?
You and I will never solve this one. You look for luck and I don't think luck is an issue. Not after hundreds of years looking, and now when we really know where to look and with the most advanced techniques the big pre-Cambrian blank remains.
Sticking a fork in Natural Selection
by xeno6696 , Sonoran Desert, Wednesday, December 07, 2011, 23:33 (4713 days ago) @ David Turell
Absence of evidence is not evidence of absence —it’s a lack of evidence. I would say the same thing then that I have said before: We don’t have enough evidence to come to a conclusion. Our knowledge would be incomplete. I ask the question again, how is the snapshot view of the fossil record false? What reason(s) do we have to accept that for a few instances in history, everything we know about life mysteriously suspended and some other process took over, other than the traditional stimulus-response nature of evolution? How is the idea wrong that the reason that the gaps are there are because we simply haven’t been lucky enough to find these transient forms?
You and I will never solve this one. You look for luck and I don't think luck is an issue. Not after hundreds of years looking, and now when we really know where to look and with the most advanced techniques the big pre-Cambrian blank remains.
No, I don't look for luck. I look for answers.
There's 148M km^2 of land. My guess is that perhaps 5% of that land has exposed Cambrian & Precambrian rock. Of that land, how much has been explored? How many life forms have ever existed?
Further, it's entirely possible that precambrian life was too soft to be preserved. How common are soft tissue fossils from even 65MyA? EXTREMELY rare.
You're content to go ahead and make decisions based on the fact that in perhaps 150years of modern research of 4.5By of history, we've explored all there is to explore. To put that in perspective, the total amount of time we've been practicing modern science is:
0.000000033% of the age of the earth.
What kind of secrets still lie in wait for us?
The big difference I think between you and me, is that I hold these two truths about science as sacred:
1. It's much easier to be wrong than right in science.
2. Perhaps more importantly, we don't know what we don't know.
#2 should be emphasized more than the first.
I value knowledge. Even modern physics--though it works--doesn't even for me make it to the level of knowledge. We know our models work, but we can never know that our models are true to fundamental reality.
Which model is correct for atoms? Points? Waves? Strings?
I think you may have fundamentally misunderstood exactly how deep doubt runs in me...
--
\"Why is it, Master, that ascetics fight with ascetics?\"
\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"
Sticking a fork in Natural Selection
by David Turell , Thursday, December 08, 2011, 01:55 (4713 days ago) @ xeno6696
I think you may have fundamentally misunderstood exactly how deep doubt runs in me...
Got it, but with the amount of time I have left in this reality I want an answer I'm comfortable with. I'll take the info I have and make a theory that feels good to me.
Try this on for Cambrian vision complexity:
http://www.nature.com/nature/journal/v480/n7376/full/nature10689.html?WT.ec_id=NATURE-2...
Sticking a fork in Natural Selection
by xeno6696 , Sonoran Desert, Thursday, December 08, 2011, 03:13 (4713 days ago) @ David Turell
I think you may have fundamentally misunderstood exactly how deep doubt runs in me...
Got it, but with the amount of time I have left in this reality I want an answer I'm comfortable with. I'll take the info I have and make a theory that feels good to me.
At the risk of sounding combative... you do realize that to me it sounds like "I want an answer for now so I'll take whatever I can get..." I'm reminded of Nietzsche's "last man" and even George Carlin's rebuke of giving up our gifts for good feelings...
It seems so anticlimactic and... tragic. It's like Caesar refusing to cross the Rubicon, or the surrender of Troy... the glory of life shines through those gaps where we don't know, and at least in my case, my feelings are irrelevant to the chase.
Try this on for Cambrian vision complexity:
http://www.nature.com/nature/journal/v480/n7376/full/nature10689.html?WT.ec_id=NATURE-2...
Part of the abstract (I can't read the full article) discusses exactly what I would think would be the explanation: An arms race. Co-evolution with prey.
--
\"Why is it, Master, that ascetics fight with ascetics?\"
\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"
Sticking a fork in Natural Selection
by dhw, Friday, December 09, 2011, 12:25 (4711 days ago) @ David Turell
MATT: But you still dodge the question. There's plenty of good reasons that we lack transitions from pre-cambrian to cambrian. The snapshot view of the fossil record *underlines* this. What right do we have to expect that the fossil record will conform to our expectations?
DAVID: I'm not dodging anything. Give me some good reasons for the gap. And is a monster developmental gap from Edicarans and Bilatarians. And the Cambrian is not a one-shot wonder as Gould presented. It is now found all over the world in Cambrian shale.
MATT: The question I'm asking, is why don't you consider that the gaps in the record are explained by the fact we haven't found those fossils, for whatever reason. (ie, too soft, etc.) this is of course the first explanation I go to when the gap discussion appears.
DAVID: You are doing a 'Darwin'. He was troubled by the gaps and expected them to be closed. There are some very persistent gaps in time and form. What would you say if they never closed?
In view of the title of this thread, I’m having difficulty discerning the focus of this discussion, so since there's a slight lull, may I step in? Darwin was indeed troubled by the gaps in the fossil record, but these have absolutely nothing to do with natural selection, which simply determined which organs and organisms survived. What so many critics ignore is that the great kerfuffle over evolution did not concern NS but common descent – the church could not abide the idea that humans and apes had a common ancestor, and that God did not create all the species separately. That went against the conventional interpretation of Genesis. So what exactly is the controversy over the Cambrian Explosion? Anti-evolutionists may claim that the gaps in the fossil record indicate that God DID create species separately. However, David has always maintained that he believes evolution took place, which means that every creature came from another creature. In that case, we must accept one of two possibilities: either there were transitional forms of which we have no record, or there were leaps from one form to another – i.e. through sudden major innovations. The latter is contrary to Darwin’s theory of gradualism, which many of us feel has been superseded by Gould’s punctuated equilibrium, and which is also coming under fire with increasing evidence of rapid change in existing organisms.
No-one has yet explained why the Cambrian “leaps†should have taken place, but if they coincided with major changes in the environment, the implication might be that innovation as well as adaptation can be sparked off by such changes. This is why epigenetics may prove to be a key factor in the process, though it’s still too early to say.
Where does God fit in? Whatever the mechanism might be that enables organisms to adapt and to innovate, David thinks it’s too complex to have assembled itself by chance, and so he believes in design. The Cambrian Explosion is an extreme example of the rich creative potential of this mechanism. Whether there are or are not any transitional fossils will only reflect the speed and completeness of the changes – the greater the speed, the more efficient and creative the mechanism, and so the greater the odds against chance. But whether there is or isn’t a designer doesn’t alter the nature of the mechanism or of the process! David also believes in pre-planning, but this is just one variation on the design theme – others being that God started it all off and then sat back to see what would happen, or that God started it off and continued to experiment. If there is no God, chance started it all off and then it followed exactly the same course as if God had pre-planned it, sat back to watch, or carried on experimenting. And so the discussion is the same as usual – chance v. design. There are no forks being stuck into natural selection or even Darwinism in general, apart from the undermining of gradualism.
Sticking a fork in Natural Selection
by David Turell , Friday, December 09, 2011, 15:02 (4711 days ago) @ dhw
dhw: And so the discussion is the same as usual – chance v. design. There are no forks being stuck into natural selection or even Darwinism in general, apart from the undermining of gradualism.
Gould did not see gradualism. The Cambrian is the biggest problem for Darwin's theory. In the 10 million year period, all of the basic parts were created for the species that exist today. This is extrememly sudden complexity. To explain my "God's" role: He planned all of this in advance. We are beginning to unpeel the onion of the genome. Epigenetic discovery shows the organism can quickly re-adapt when it has to. The guiding mechanisms to reach H. sapiens are there. It took only 6 million years to develop a brilliant brain like dhw's. And the chimps are in stasis. Only one of us species are the chosen among the species.
Sticking a fork in Natural Selection
by dhw, Saturday, December 10, 2011, 07:54 (4711 days ago) @ David Turell
dhw: And so the discussion is the same as usual – chance v. design. There are no forks being stuck into natural selection or even Darwinism in general, apart from the undermining of gradualism.
DAVID: Gould did not see gradualism. The Cambrian is the biggest problem for Darwin's theory. In the 10 million year period, all of the basic parts were created for the species that exist today. This is extremely sudden complexity. To explain my "God's" role: He planned all of this in advance. We are beginning to unpeel the onion of the genome. Epigenetic discovery shows the organism can quickly re-adapt when it has to. The guiding mechanisms to reach H. sapiens are there. It took only 6 million years to develop a brilliant brain like dhw's. And the chimps are in stasis. Only one of us species are the chosen among the species.
I can’t see any evolutionary disagreement between us here, as it’s the speed of change that knocks Darwin’s gradualism on the head. If you believed that your God created every species separately, there would indeed be a fundamental conflict with Darwin, but instead you argue that God preplanned everything. That’s one design theory, though I can’t see that it has any advantage over the theory that God didn’t know what he was doing initially and experimented as he went along, or that he knew what he wanted but had to experiment in order to get there. The Cambrian would in both cases have been a period of intense creativity. So even for a believer there’s more than one option, and none of these options in any way contradicts the rest of Darwin’s theory. The chance alternative, of course, has to go back to the self-assembly of the mechanism, but Darwin doesn’t cover its origin anyway. And so the Cambrian is a problem for gradualism, but not for natural selection or Darwinism in general.
In passing, I'd like to add something to your statement, which I'm sure you will approve of! As far as I can make out, epigenetics only covers adaptation – just as you have said yourself. Adaptation on its own is not enough to account for new organs and species (though as both Tony and Darwin often point out, it's very hard to define "species"). There has to be innovation as well. Perhaps – just perhaps – epigenetics may shed light on this too, but whatever the mechanism, it has to increase the odds against chance.
Sticking a fork in Natural Selection
by David Turell , Saturday, December 10, 2011, 16:01 (4710 days ago) @ dhw
In passing, I'd like to add something to your statement, which I'm sure you will approve of! As far as I can make out, epigenetics only covers adaptation – just as you have said yourself. Adaptation on its own is not enough to account for new organs and species (though as both Tony and Darwin often point out, it's very hard to define "species"). There has to be innovation as well. Perhaps – just perhaps – epigenetics may shed light on this too, but whatever the mechanism, it has to increase the odds against chance.
Exactly what my book predicted will happen. As chance disappears God appears.
Sticking a fork in Natural Selection
by xeno6696 , Sonoran Desert, Saturday, December 10, 2011, 22:03 (4710 days ago) @ dhw
dhw,
In passing, I'd like to add something to your statement, which I'm sure you will approve of! As far as I can make out, epigenetics only covers adaptation – just as you have said yourself. Adaptation on its own is not enough to account for new organs and species (though as both Tony and Darwin often point out, it's very hard to define "species"). There has to be innovation as well. Perhaps – just perhaps – epigenetics may shed light on this too, but whatever the mechanism, it has to increase the odds against chance.
One of the key findings of the beta-lactamase experiment I discussed earlier, is that when the E. coli cells were under stress, they "invented" the ability to metabolise lactase. Why can you not extend the logic of "need precipitates change" to organs, if they do indeed work for genes?
I keep getting tripped up in Natural Selection discussions, partially because I always lose sight of the fact: Evolution by Natural Selection works ONLY on a demand basis... the organism comes under stress and then the organism adapts... again I ask, why is there some need to assume that need doesn't precipitate change?
Both yourself and David have chastised me about the idea of currently accepted evolutionary theory as not "being fast enough."
But I really don't understand what's wrong about the idea of a demand-based evolutionary system--the one we have.
I've been bumbling about as of late, but I must stress that I have a great deal of confusion... evolution isn't fast enough, but we accept it... I understand evolution as a demand-based system, but I don't understand how it's unacceptable for current theory to "not be fast enough." To my mind, it works like this:
Normal reproduction results in a great deal of non-deleterious mutations. If the environment is stable over time, I understand that these changes will accumulate--but likely not manifest, because largely, mutations that don't result in death result in:
1. Dormant abilities that don't appear to have any immediate use.
2. Completely benign changes.
The changes don't manifest themselves until "Natural Selection," ie,
3. the organism gains a pure benefit.
4. The environment shifts (either through mobility, seasons, or something else like disaster...)
From my perspective, Natural Selection IS the prime motivator of change. IF an organism isn't required to change until its under stress, then clearly it doesn't really matter where organismal change comes from: 1M dormant epigenetic changes combined with 1M non-beneficial changes means nothing if something about the organism doesn't change in regards to the environment.
I realize David and you both consider this a passive process, but it's only passive from a naive perspective... ie, the process of a new individual being created (sexually or asexually) is hardly what I would call passive. It's passive from an individual perspective--yet none of us would have a problem with the argument that after the act of intercourse, our kids came about by processes nearly completely uncontrolled from ourselves. (I don't see how the "passive" argument holds...)
--
\"Why is it, Master, that ascetics fight with ascetics?\"
\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"
Sticking a fork in Natural Selection
by David Turell , Sunday, December 11, 2011, 00:45 (4710 days ago) @ xeno6696
But I really don't understand what's wrong about the idea of a demand-based evolutionary system--the one we have.
I do agree with you that the environment produces demands on each organism to which it must respond if those demands are serious enough.
Normal reproduction results in a great deal of non-deleterious mutations. If the environment is stable over time, I understand that these changes will accumulate--but likely not manifest, because largely, mutations that don't result in death result in:1. Dormant abilities that don't appear to have any immediate use.
2. Completely benign changes.
The changes don't manifest themselves until "Natural Selection," ie,
3. the organism gains a pure benefit.
4. The environment shifts (either through mobility, seasons, or something else like disaster...)
From my perspective, Natural Selection IS the prime motivator of change. IF an organism isn't required to change until its under stress,
Whoa: You or we need to define terms. Natural selection is by my definition is a process that comes into play as the organism is challenged by changes in its milieu. The motivator is the changing environment. NS is the result of the competition of the organism with the changes.
I realize David and you both consider this a passive process, but it's only passive from a naive perspective... ie, the process of a new individual being created (sexually or asexually) is hardly what I would call passive. It's passive from an individual perspective--yet none of us would have a problem with the argument that after the act of intercourse, our kids came about by processes nearly completely uncontrolled from ourselves. (I don't see how the "passive" argument holds...)
This is apples and oranges. The act of reproduction is NOT any form of selection. Selection occurs AFTER reproduction produces a new organism in a hopefully new and capable form.
Sticking a fork in Natural Selection
by xeno6696 , Sonoran Desert, Sunday, December 11, 2011, 16:57 (4709 days ago) @ David Turell
But I really don't understand what's wrong about the idea of a demand-based evolutionary system--the one we have.
I do agree with you that the environment produces demands on each organism to which it must respond if those demands are serious enough.
Normal reproduction results in a great deal of non-deleterious mutations. If the environment is stable over time, I understand that these changes will accumulate--but likely not manifest, because largely, mutations that don't result in death result in:1. Dormant abilities that don't appear to have any immediate use.
2. Completely benign changes.
The changes don't manifest themselves until "Natural Selection," ie,
3. the organism gains a pure benefit.
4. The environment shifts (either through mobility, seasons, or something else like disaster...)
From my perspective, Natural Selection IS the prime motivator of change. IF an organism isn't required to change until its under stress,
Whoa: You or we need to define terms. Natural selection is by my definition is a process that comes into play as the organism is challenged by changes in its milieu. The motivator is the changing environment. NS is the result of the competition of the organism with the changes.
I'm looking at Natural Selection in a microscope: we have a whole organism and its population. A "Selection event" occurs and then the organisms respond. The key to my thinking (and why I've been stubbing my toes with you and dhw) is that I don't see how we can say Natural Selection isn't the driving force of evolution when we agree that:
1. We have a "demand-based" evolutionary system.
2. The cause of the demand are called "selection events."
3. A species (viewed as a group) changes in response to the selection events.
Lets say we're dealing with the horse example. When you look at the progression of horse fossils, lets think of each fossil as a snapshot. Hyrocotherum was clearly under selective pressure to become mesohippus--for a brief period of time.
If we agree that the system is demand-based, and we agree that selection events are the cause... it thus follows that natural selection is the primary cause of speciation. I don't see how it makes any difference that epigenetics or random mutation are functions that create the genetic variation when we have a pretty clear image of cause-and-effect in my mind.
Does this make my confusion a little more clear?
As an aside--I know no other place to put this--I'm starting to think that the distinctions we make between species is in many cases spurious... it seems to me that they are as arbitrary as the borders on a map.
I realize David and you both consider this a passive process, but it's only passive from a naive perspective... ie, the process of a new individual being created (sexually or asexually) is hardly what I would call passive. It's passive from an individual perspective--yet none of us would have a problem with the argument that after the act of intercourse, our kids came about by processes nearly completely uncontrolled from ourselves. (I don't see how the "passive" argument holds...)
This is apples and oranges. The act of reproduction is NOT any form of selection. Selection occurs AFTER reproduction produces a new organism in a hopefully new and capable form.
I can think of some corner cases around what you say here, but I think we're talking past each other here... you've said before that you don't see how a passive process could bring about a species. What I was attempting to argue here, is that most biological things we take for granted--are passive processes--they require no direct intervention from the organism itself.
--
\"Why is it, Master, that ascetics fight with ascetics?\"
\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"
Sticking a fork in Natural Selection
by David Turell , Sunday, December 11, 2011, 23:56 (4709 days ago) @ xeno6696
What I was attempting to argue here, is that most biological things we take for granted--are passive processes--they require no direct intervention from the organism itself.
But they do. Epigenetics is on just that point, as Shapiro points out in his book.
Sticking a fork in Natural Selection
by dhw, Sunday, December 11, 2011, 16:45 (4709 days ago) @ xeno6696
MATT: One of the key findings of the beta-lactamase experiment I discussed earlier, is that when the E. coli cells were under stress, they "invented" the ability to metabolise lactase. Why can you not extend the logic of "need precipitates change" to organs, if they do indeed work for genes?
Round we go. Matt, you have sent me rooting back into your past posts. On 27 July at 20.42 you stressed that “the beta-lactamase experiment was NOT integral to the species. Several generations continued with the bacteria moving along just fine – only more slowly…the gene sequence changed in a manner consistent with random mutations…it clearly demonstrates that SOME beneficial changes CAN come by chance.†Now you are arguing that it wasn’t by chance but by need. You really can’t have it both ways – either this was a random mutation (your original argument) or it was an adaptation required by the environment.
MATT: I keep getting tripped up in Natural Selection discussions, partially because I always lose sight of the fact: Evolution by Natural Selection works ONLY on a demand basis... the organism comes under stress and then the organism adapts... again I ask, why is there some need to assume that need doesn't precipitate change?
When have I ever argued that need doesn’t precipitate change? That is the whole point of adaptation! But your confusion over the beta-lactamase experiment highlights the issue of what causes change. One cause is the need to adapt, and the other is random mutation. Nobody knows to what extent these two causes overlap. All we know is that if the changes do not enable the organism to survive in the given environment, Natural Selection will result in its being eliminated.
MATT: Both yourself and David have chastised me about the idea of currently accepted evolutionary theory as not "being fast enough."
No, that has not been the issue at all with me. You have been chastised firstly because you insisted that NS was synonymous with evolution, and now because: “From my perspective, Natural Selection IS the prime motivator of change.†NS does not motivate anything. Changes in the environment may well be the prime motivator, because organisms must ADAPT or die, but random mutations are the other motivator and may account for INNOVATIONS (new organs). But again these will not survive unless they are useful in the given environment. NS does not MOTIVATE either form of change – it only determines whether these changes will survive. It is passive (David’s term, not mine) in the sense that it doesn’t create anything. It only works on what already exists. The argument concerning the SPEED of evolution has nothing to do with NS. David’s point is that the speed is too great for chance to have created this vast variety of organs and organisms in the given amount of time.
MATT: But I really don't understand what's wrong about the idea of a demand-based evolutionary system--the one we have.
Nothing is wrong with it. All that’s wrong is your insistence that Natural Selection takes place before there is something to select.
MATT: I've been bumbling about as of late.
Because you keep trying to prove that Natural Selection takes place before there is something to select.
MATT: I realize David and you both consider this a passive process, but it's only passive from a naive perspective... ie, the process of a new individual being created (sexually or asexually) is hardly what I would call passive.
DAVID: Selection occurs AFTER reproduction produces a new organism in a hopefully new and capable form.
Exactly. Or to put it another way, Natural Selection cannot take place until there is something to select.
Summary: NS does not create anything. Random mutations may be creative. NS does not motivate anything. Changes in the environment motivate changes in the organism (= adaptation). NS decides which changes – by random mutation or adaptation– will survive. Nothing can be selected, even by Nature, before there is something to select.
QED, LOL, DHW
Sticking a fork in Natural Selection
by xeno6696 , Sonoran Desert, Sunday, December 11, 2011, 18:02 (4709 days ago) @ dhw
dhw:
Round we go. ... Now you are arguing that it wasn’t by chance but by need. You really can’t have it both ways – either this was a random mutation (your original argument) or it was an adaptation required by the environment.
Not quite... you missing some detail here. In the experiment, the bacteria without the lactamase gene was in an environment where it could still engage in pyrolysis. Analysis of the genes over generations demonstrated that in the case for the bacteria, random combinations of their genome ultimately culminated in one group gaining an ability to digest lactose. In the case of the bacteria (and this was the only case in question at the time I posted it) this was a novel mechanism created purely by chance. The bacteria were not in stressed conditions--They couldn't be. Bacteria - lactamase gene = Bacteria that "never knew what it was missing." It's beyond scope here, but there are a series of skeptical questions you can ask about this experiment, but we can save those for later.
I don't have the time to dig for old posts, but clearly even in my wording you grabbed above, I was only talking about one species, clearly isolated and in a laboratory. The context of the original post I DO remember, was in the paraphrased assertion (by you or David) that random processes can't generate anything. My post you quoted from above was to counter THAT claim. Also, the selection event in the case of the bacteria was when it was introduced into a lactose-rich medium with non-lactamase species and it dominated in terms of population. No selection ocurred in the laboratory until THAT happened.
I have also *never* asserted that evolution was a purely random phenomenon. I remember posting some quotes from a Massimo Pigliucci book that was arguing precisely the opposite--that the only alternative to design was a purely random process.
MATT: I keep getting tripped up in Natural Selection discussions, partially because I always lose sight of the fact: Evolution by Natural Selection works ONLY on a demand basis... the organism comes under stress and then the organism adapts... again I ask, why is there some need to assume that need doesn't precipitate change?
When have I ever argued that need doesn’t precipitate change? That is the whole point of adaptation! But your confusion over the beta-lactamase experiment highlights the issue of what causes change. One cause is the need to adapt, and the other is random mutation. Nobody knows to what extent these two causes overlap. All we know is that if the changes do not enable the organism to survive in the given environment, Natural Selection will result in its being eliminated.
In the lactamase example, there wasn't a clear "demand" for the function. Maybe this is your suggestion? That evolution isn't purely a demand-driven enterprise? It's plausible but it's a hard case to make.
MATT: Both yourself and David have chastised me about the idea of currently accepted evolutionary theory as not "being fast enough."
... NS does not motivate anything. Changes in the environment may well be the prime motivator, because organisms must ADAPT or die, but random mutations are the other motivator and may account for INNOVATIONS (new organs). But again these will not survive unless they are useful in the given environment. NS does not MOTIVATE either form of change – it only determines whether these changes will survive. It is passive (David’s term, not mine) in the sense that it doesn’t create anything. It only works on what already exists. The argument concerning the SPEED of evolution has nothing to do with NS. David’s point is that the speed is too great for chance to have created this vast variety of organs and organisms in the given amount of time.
What is a selection event, and what is the result of a selection event? What is a selection event's relationship to Natural Selection?
My answer: Natural selection we have previously agreed is a filter that weeds out the unfit. Is it not true that a selection event is the beginning of the process that culminates in what comes out of the filter? I answer yes.
An organism (as in the lactamase example) will collect all benign changes over time--BUT until something happens in the environment (selection event) there is no change to record.
Your answer: ????
Summary: NS does not create anything. Random mutations may be creative. NS does not motivate anything. Changes in the environment motivate changes in the organism (= adaptation). NS decides which changes – by random mutation or adaptation– will survive. Nothing can be selected, even by Nature, before there is something to select.
QED, LOL, DHW
Perspectivism. NS IS responsible for what we see!
No event-->no selection-->no observed change in an organism.
The species is in stasis.
Event-->selection-->observed change in an organism.
The species has become "something else."
Who's laughing now?
--
\"Why is it, Master, that ascetics fight with ascetics?\"
\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"
Sticking a fork in Natural Selection
by dhw, Sunday, December 11, 2011, 23:20 (4709 days ago) @ xeno6696
These posts are getting messy. Let’s deal with the beta-lactamase experiment first. On 27 July it was a random mutation; on 10 December the cells were under stress and responded by “inventing†the ability to metabolise lactase (adaptation); on 11 December they were not under stress and created a novel mechanism by chance. You now say there was a random mutation, but
“the selection event in the case of the bacteria was when it was introduced into a lactose-rich medium with non-lactamase species and it dominated in terms of population. No selection ocurred in the laboratory until THAT happened.†Followed by: “[...]until something happens in the environment (selection event) there is no change to record. Your answer: ????
My answer is that the change was the random mutation, but since the new form was in isolation, no selection occurred till the two “species†were put together. Then the new organism dominated. A classic case of Darwinian evolution: a chance mutation gives one form an advantage over another when they are in competition, and natural selection ensures that the species more suited to the environment flourishes. NS selects from EXISTING organisms; it doesn't create them. More about “selection event†in a moment.
Briefly: I’ve never claimed that random processes can’t generate anything. Change is caused by adaptation and random mutations, but we don’t know to what extent they overlap. And: MATT: “I have also *never* asserted that evolution was a purely random process.†I have *never* asserted that you did.
MATT: The key to my thinking (and why I've been stubbing my toes with you and dhw) is that I don't see how we can say Natural Selection isn't the driving force of evolution when we agree that:
1. We have a "demand-based" evolutionary system. 2. The cause of the demand are called "selection events." 3. A species (viewed as a group) changes in response to the selection events.
One of the causes of confusion is your continual shifting of ground. Now we have two vague new terms. I accept “demand-based†as meaning that survival demands suitability to an environment.
MATT: What is a selection event, and what is the result of a selection event? What is a selection event's relationship to Natural Selection? My answer: Natural selection we have previously agreed is a filter that weeds out the unfit. [Three cheers from David and me!] Is it not true that a selection event is the beginning of the process that culminates in what comes out of the filter? I answer yes.
So do I, but why call it a “selection event� Why not call it an environmental change? Here is the process: 1) environmental change, 2) adaptation (maybe useful mutation), 3) NS (the filter). Organisms won’t adapt until this “event†(environmental change) takes place. So how can the final filtering stage be the driving force or “primary cause� The driving force is the need for organisms to cope with the environment. NS determines which will succeed. I hope you’re not pretending the term “selection event†is synonymous with Natural Selection!
MATT: I don't see how it makes any difference that epigenetics or random mutation are functions that create the genetic variation when we have a pretty clear image of cause-and-effect in my mind. Does this make my confusion a little more clear?
I agree that whether these changes are due to epigenetics or random mutations makes no difference to the sequence of cause and effect, as described above. WE do not have a pretty clear image of cause-and-effect in YOUR mind, but the source of your confusion is clear to me: you think the effect – NS deciding which changes will survive – takes place before the cause – new environmental conditions or random mutations bringing about the changes from which Natural Selection will select.
MATT: Perspectivism. NS IS responsible for what we see!
Yes, because NS has ensured that we see the species that were best suited to survival. That doesn’t make it the driving force that CREATES the new species.
MATT: No event-->no selection-->no observed change in an organism.
The species is in stasis.
Event-->selection-->observed change in an organism.
Wrong order: event – change in organism – selection - what we see. There can't be selection till there's something to select from! Your event (environmental change) may cause the changes that Natural Selection will select or reject.
MATT: The species has become "something else."
Agreed.
MATT: Who's laughing now?
Not laughing. Screaming.
MATT: As an aside--I know no other place to put this--I'm starting to think that the distinctions we make between species is in many cases spurious... it seems to me that they are as arbitrary as the borders on a map.
As I mentioned in my post of 10 December at 07.54 (very early for me!), Tony and Charles Darwin raised the same problem on many occasions.
Sticking a fork in Natural Selection
by David Turell , Monday, December 12, 2011, 00:10 (4709 days ago) @ dhw
MATT: No event-->no selection-->no observed change in an organism.
The species is in stasis.
Event-->selection-->observed change in an organism.Wrong order: event – change in organism – selection - what we see. There can't be selection till there's something to select from! Your event (environmental change) may cause the changes that Natural Selection will select or reject.
Of Course!!!
Sticking a fork in Natural Selection
by David Turell , Monday, December 12, 2011, 00:03 (4709 days ago) @ xeno6696
Perspectivism. NS IS responsible for what we see!
No event-->no selection-->no observed change in an organism.
The species is in stasis.
Event-->selection-->observed change in an organism.The species has become "something else."
The process of natural selection is ultimately the final filter for survival. But NS passively waits until rival forms appear and then what is presented to it is actively chosen. NS is an active process of what is presented to it. NS has nothing to do with the formation of the presented forms. NS has nothing to do until the rivals are presented to it.
Sticking a fork in Natural Selection
by xeno6696 , Sonoran Desert, Monday, December 12, 2011, 01:18 (4709 days ago) @ David Turell
Perspectivism. NS IS responsible for what we see!
No event-->no selection-->no observed change in an organism.
The species is in stasis.
Event-->selection-->observed change in an organism.The species has become "something else."
The process of natural selection is ultimately the final filter for survival. But NS passively waits until rival forms appear and then what is presented to it is actively chosen. NS is an active process of what is presented to it. NS has nothing to do with the formation of the presented forms. NS has nothing to do until the rivals are presented to it.
I don't see in your response and in my words above--where we disagree.
"What we see" is synonymous with "observe" and it is THAT description that I'm after. In the horse example, we *observe* fifteen places on the branches of of life for modern horses. If you look at mesohippus to megahippus consider that each fossil is a snapshot of time: all the changes collected over time and selected against resulted in the transition to megahippus. At each snapshot, we have untold numbers of selection events going on. The direct cause for us witnessing hypohippus, was a series of selection events acting upon the genome of mesohippus and the intermediate form kalobattipus.
The genome does all the work. But the *cause* for our witnessed change are the events that pushed these organisms to take the forms we've witnessed.
--
\"Why is it, Master, that ascetics fight with ascetics?\"
\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"
Sticking a fork in Natural Selection
by David Turell , Monday, December 12, 2011, 02:38 (4709 days ago) @ xeno6696
Perspectivism. NS IS responsible for what we see!
No event-->no selection-->no observed change in an organism.
The species is in stasis.
Event-->selection-->observed change in an organism.The species has become "something else."
But only if you add the following: Event--> genome at work--> changed organism offered for selection/survival process--> process of selection--> changed organism now survives to reproduce.
Sticking a fork in Natural Selection
by David Turell , Saturday, August 31, 2013, 20:08 (4080 days ago) @ David Turell
More on the book What Darwin got Wrong. They throw out Natural Selection as a theory:-http://www.evolutionnews.org/2013/08/natural_selecti_2075991.html
Sticking a fork in Natural Selection
by dhw, Sunday, September 01, 2013, 18:08 (4079 days ago) @ David Turell
DAVID: More on the book What Darwin got Wrong. They throw out Natural Selection as a theory:-http://www.evolutionnews.org/2013/08/natural_selecti_2075991.html-And there was me thinking Natural Selection was as simple and straightforward a theory as you can get. Let me tell you what I think it means: the process whereby those organisms best adapted to the prevailing environment will survive and flourish, while less well adapted organisms will die out. Does anyone object to this definition? It explains why there are variations within species, and it establishes a link between innovation and the environment, but it does not explain innovation itself. I agree that Darwin was wrong to attribute the origin of species to Natural Selection in his title, since NS never originated anything, but that doesn't mean we should "throw it out", or that it is "empty"!-QUOTE: "Natural history is just one damned thing after another. This should seem, on reflection, unsurprising since, to repeat, natural history is a species of history, and history is itself just one damned thing after another... Darwin made the same sort of mistake that Marx did: he imagined that history is a theoretical domain; but what there is, in fact, is only a heterogeneity of causes and effects."-Darwin examined one damned thing after another in his attempt to find out why species are as they are. From the series of causes and effects he extrapolated the above theory. He did not treat history as a theory. He examined history and based his theory on it.-QUOTE: "There aren't, and never were, pigs with wings. That there aren't and weren't needs to be explained; but the explanation surely cannot be selectionist. Mother Nature never had any winged pigs to select against; so pigs not having wings can't be an adaptation. We think such considerations strongly suggest that there are endogenous constraints -- quite possibly profound ones -- on phenotypes. As far as we can tell, this is slowly becoming the received view in evolutionary biology."-Of course the explanation is not selectionist, and of course it's because Mother Nature never had winged pigs to select against. Mother Nature can only select from what exists, and of course not having something can't be an adaptation unless it's the shedding of something that exists but has become redundant or deleterious. And of course there are endogenous constraints. I don't accept the theory of random mutations, but randomness itself would be a constraint ... you only get what chance produces. I would say that the "intelligent cell" is also under constraint: if a pig is already adapted to its environment and flourishes, (a) there is no need for it to sprout wings, and (b) the changes necessary for it to fly would be so colossal that it would have to lose almost every aspect of its pigginess. What on Earth does this have to do with Natural Selection? NS does not create or prevent innovations. It simply tells us that the existing pigginess of the pig has enabled it to survive and flourish in its piggy-friendly environment, while un-pigs or less piggy pigs have disappeared.