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Author Topic:   WTF is wrong with people
Percy
Member
Posts: 22389
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 361 of 457 (708595)
10-11-2013 9:39 AM
Reply to: Message 360 by NoNukes
10-11-2013 9:15 AM


Re: Environment-driven evolution
Hi NoNukes,
My view of breeding and evolution is that they differ only in the selection pressures. I think Darwin saw it the same way. I suspect you're calling breeding a dead end because it doesn't produce new species, but that's not a limitation of artificial selection. It has more to do with the goals of breeders and the constraints of time for long-lived species. Certainly we have no trouble using artificial selection to produce new species when they're very short-lived.
--Percy

This message is a reply to:
 Message 360 by NoNukes, posted 10-11-2013 9:15 AM NoNukes has replied

Replies to this message:
 Message 362 by NoNukes, posted 10-11-2013 12:22 PM Percy has replied

  
NoNukes
Inactive Member


Message 362 of 457 (708613)
10-11-2013 12:22 PM
Reply to: Message 361 by Percy
10-11-2013 9:39 AM


Re: Environment-driven evolution
I suspect you're calling breeding a dead end because it doesn't produce new species, but that's not a limitation of artificial selection.
I may have been unclear about that. A breed is not necessarily a dead end, but the process of breeding as practiced by say collie breeders is indeed a dead end. The process is designed to create a specific phenotype and to reject the breeder's idea of unacceptable diversity. A mutation that generates more powerful legs on a collie would get kicked out ot the gene pool by breeders even if such a thing would produce a survival advantage out in the wild.
Obviously we can stop the culling process and allow divergent breeds to exist, and I did not mean to say anything about that. And of course, we might imagine a human breeder that is actually practicing eugenics. Not talking about that either. And neither is Faith.
My view of breeding and evolution is that they differ only in the selection pressures.
Yes, but that turns out to make a huge difference and is what drives some people to be quite vehement about the distinction. Faith seems to take this vehemence as indication that people don't understand her position. (I won't be mentioning Faith anymore in this thread as I find doing so tests my restraint).
Other than being more specific about some things that are different, I don't think I've said anything that disagrees with your stated view. There are some common things to say about breeding and evolution, but in this discussion the distinctions are quite important.
Edited by NoNukes, : No reason given.
Edited by NoNukes, : No reason given.
Edited by NoNukes, : No reason given.

Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)
I believe that a scientist looking at nonscientific problems is just as dumb as the next guy.
Richard P. Feynman
If there is no struggle, there is no progress. Those who profess to favor freedom, and deprecate agitation, are men who want crops without plowing up the ground, they want rain without thunder and lightning. Frederick Douglass

This message is a reply to:
 Message 361 by Percy, posted 10-11-2013 9:39 AM Percy has replied

Replies to this message:
 Message 363 by PaulK, posted 10-11-2013 12:38 PM NoNukes has seen this message but not replied
 Message 377 by Percy, posted 10-12-2013 7:55 AM NoNukes has replied

  
PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


(2)
Message 363 of 457 (708618)
10-11-2013 12:38 PM
Reply to: Message 362 by NoNukes
10-11-2013 12:22 PM


Re: Environment-driven evolution
As I've been saying to Faith it mainly comes down to rates. Adaptive evolution is the combination of two processes, one generating variations, the other culling them.
Artificial selection drastically emphasises the culling, and in the short term it will deplete the variation needed fuel the process, because of the greatly accelerated rate of of selection. As a result any attempt to use the breeding process as a guide to evolution will get a very one-sided picture.
(And, I will note, when even the limited role that mutations have played in actual breeding is denied or minimised the picture is even more one-sided and inaccurate.)

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 Message 365 by Faith, posted 10-11-2013 1:17 PM PaulK has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 364 of 457 (708620)
10-11-2013 12:55 PM
Reply to: Message 346 by AZPaul3
10-10-2013 7:27 PM


Re: Environment-driven evolution
At about 2,100,000,000 mutations entering the human genome every year, that would take a whole lot of swallowing.
The entire human genome with its 2 billion mutations per year is not what loses genetic diversity. It's any particular line of subpopulations or variations that is continuing to evolve by splitting off new subpopulations. Human beings have enough genetic diversity so that any group can reproduce with any other despite great differences, but many animals don't have that much genetic diversity in any particular variety or "species" etc.
My claim has been that evolution comes to an end down a PARTICULAR LINE of variation as it continues to split into subpopulations, and ring species are probably the best example of what I'm talking about. If the last "species" in the ring can't breed with the first or other earlier populations, my guess would be the reason is the reduction in genetic diversity in the last one. Somebody wanted me to allow for other ways breeding can come to a stop, but in this kind of example the evolved genetic mismatch seems to me to be the most likely reason.
" Once Natural Selection or any other 'mechanism of change' that brings about a new subpopulation kicks in then you have the trend to reduced genetic diversity"
is just pure bullshit as you have been shown many times.
Natural Selection *selects,* that is, it creates a new subpopulation of those best adapted in a particular situation. The new subpopulation is very likely to be appreciably smaller at its founding than the original just because how many adaptive alleles or other genetic influences are you going to find in any population with respect to a particular environmental challenge? Not all NS has this drastic an effect so this can be taken as the most extreme example of how it works.
Different reasons aside, domestic breeding is the best comparison because it also selects and creates new smaller subpopulations to bring out the selected traits.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 346 by AZPaul3, posted 10-10-2013 7:27 PM AZPaul3 has replied

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 Message 370 by AZPaul3, posted 10-11-2013 3:07 PM Faith has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 365 of 457 (708624)
10-11-2013 1:17 PM
Reply to: Message 363 by PaulK
10-11-2013 12:38 PM


Re: Environment-driven evolution
As I've been saying to Faith it mainly comes down to rates. Adaptive evolution is the combination of two processes, one generating variations, the other culling them.
I think you mean "generating genetic variability or diversity," not "variations," since it is the selective and isolating processes that generate new varieties or races or "species" etc. There is only one process that could possibly generate new genetic diversity and that is mutation, which as everybody agrees doesn't generate much in the short term. All the other processes split populations, which may not reduce genetic diversity right away if the populations are both large enough to contain the range of alleles in the original, (though it will change allele frequencies since you aren't going to get the exact same proportions of alleles in a random population split). Depends on the numbers in each and the original genetic diversity level as well.
Artificial selection drastically emphasises the culling, and in the short term it will deplete the variation needed fuel the process, because of the greatly accelerated rate of of selection.
Thank you. Now you need to admit that this happens at least in SOME situations in the wild. For the rest I realize I'll have to make the case better that it also occurs wherever you are getting new varieties since that's the main point of contention. Meanwhile, the artificial selection situation as you've described it IS my model for what happens overall, though of course it's far more drastic than the usual situation in the wild.
As a result any attempt to use the breeding process as a guide to evolution will get a very one-sided picture.
But it nevertheless provides the principle I have in mind, which I'm arguing operates wherever new varieties are being developed at a much slower and less conspicuous rate. (But slower in decades, not millennia or millions of years, and culling is still going to overwhelm the mutations at that rate).
(And, I will note, when even the limited role that mutations have played in actual breeding is denied or minimised the picture is even more one-sided and inaccurate.)
Why, when all that happens to those mutations is that they become part of the breed or not, and the breed is still characterized by very small genetic diversity? If mutations DO add alleles or anything that gets passed on, then they get treated exactly as alleles get treated when selection and isolation create small subpopulations by culling individuals from it. You've got your new trait (supposedly) but it's locked into a population of less genetic diversity.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 363 by PaulK, posted 10-11-2013 12:38 PM PaulK has replied

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 Message 369 by PaulK, posted 10-11-2013 2:33 PM Faith has not replied

  
Tangle
Member
Posts: 9489
From: UK
Joined: 10-07-2011
Member Rating: 4.9


Message 366 of 457 (708628)
10-11-2013 1:32 PM
Reply to: Message 359 by Percy
10-11-2013 8:55 AM


Re: Environment-driven evolution
Percy writes:
.....but I'm confident that Faith will interpret your lack of mention of selection in that particular message as an indication that you don't believe selection is important. Incredible, I know, but there it is.
Ok, so for the record, selection is an important part of the process and has been so for 150 years ;-)
But now I'm going to really fcuk things up. It's not always as simple as this is it?
We now have the whole new world of evo devo which may allow the phenotype to drive the genotype - a whole inversion of what we, or at least I, used to think. This from the wiki:
Similarly, organismal form can be influenced by mutations in promoter regions of genes, those DNA sequences at which the products of some genes bind to and control the activity of the same or other genes, not only protein-specifying sequences. This finding suggested that the crucial distinction between different species (even different orders or phyla) may be due less to differences in their content of gene products than to differences in spatial and temporal expression of conserved genes. The implication that large evolutionary changes in body morphology are associated with changes in gene regulation, rather than the evolution of new genes, suggested that Hox and other "switch" genes may play a major role in evolution, something that contradicts the neo-darwinian synthesis.
Evolutionary developmental biology - Wikipedia
Now that is a real shocker.
But I've always felt that there was something missing from the ToE, something to explain major changes that just don't seem credible using the standard bit by bit model.
I studied biology at degree level in the 70’s and spent a long time looking at the sequence of development of jaw bone into the bones of the middle ear - a clasical demonstration of long term evolution. It was undeniable, I held the bones in my hands - or plaster copies of them - it happened and it was evolution wot did it, but like our creationist friends it just did not seem possible. Evo Devo though seems to supply another route.
I only wish I'd kept studying it - now it's all so advanced that I'd have to devote far too much of my life to understand it.

Life, don't talk to me about life - Marvin the Paranoid Android

This message is a reply to:
 Message 359 by Percy, posted 10-11-2013 8:55 AM Percy has replied

Replies to this message:
 Message 378 by Percy, posted 10-12-2013 8:08 AM Tangle has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 367 of 457 (708629)
10-11-2013 1:33 PM
Reply to: Message 354 by Percy
10-11-2013 7:39 AM


Re: Environment-driven evolution
That wasn't what Tangle was calling daft. What's daft is your idea that merely isolating a subpopulation will produce changes in allele frequencies sufficient for producing phenotypic change. As has been pointed out to you, if this were the case then we would see it happening in both captive and natural subpopulations over and over and over again, but we do not.
We DO see it in natural subpopulations: ring species. And anywhere else you have many "species" of a Species.
In captive populations you don't have a reproductively isolated population that you can inbreed over enough generations over enough time to see the effect. They may be introducing new mates to avoid the problems of breeding close relatives, but then not insuring that the mates become part of a reproductively isolated group that can be inbred over generations. Also you may have founders that are already genetically reduced to the point that you aren't going to see much variation anyway.
Edited by Faith, : No reason given.

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 Message 354 by Percy, posted 10-11-2013 7:39 AM Percy has seen this message but not replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 368 of 457 (708636)
10-11-2013 1:43 PM
Reply to: Message 351 by AZPaul3
10-10-2013 10:21 PM


Re: Environment-driven evolution
All those mechanisms act in that way, only mutations don't. Some population splits can occur WITHIN a larger population TOO, as I've also said a number of times. I believe Drift can be described that way. Whenever a particular allele or set of alleles occurs in higher frequency that does not spread through the entire larger population, THAT's the equivalent of a population split, creating its own reproductively isolated subpopulation within the larger.
Oh, my lady, how can you get so much wrong in such a short amount of space.
Yes, in massive populations over an extended range the population in the eastern quarter may have an allele frequency quite different than the population in the western quarter. We already know this. Over time the eastern and western populations may diverge to the point of separate identities. But this was not caused because of some intrinsic feature of allele frequency but because of the reproductive isolation of the two populations over a large geographic region.
Seems to me where you are going to see this effect soonest and most dramatically is in the smaller subpopulations not the larger. When there is a population split, both populations are going to have different allele frequencies just because the alleles that belong to each are randomly "selected" out of the original pool in the split. You MUST get different allele frequencies. But it's going to take generations of inbreeding for their effect on the overall population to show up, and the greater the original numbers the more generations it will take.
In a small subpopulation, however, such as the ten lizards that were isolated from the main population of lizards in the Dawkins video, the effect should be obvious in a shorter time period, such as the decades recognized in that case. Certainly the proportions of alleles in the new population must be greatly different from those in the mother population, and in fact it's very probable that some alleles in the original population didn't make it at all into the new population. That would depend on how much genetic diversity was originally present, but let's assume it was fairly high.
I want to get to the rest of your post as well as others here, but I can't do it right now.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


(1)
Message 369 of 457 (708640)
10-11-2013 2:33 PM
Reply to: Message 365 by Faith
10-11-2013 1:17 PM


Re: Environment-driven evolution
quote:
I think you mean "generating genetic variability or diversity," not "variations," since it is the selective and isolating processes that generate new varieties or races or "species" etc
You are wrong in more than one way here. First you are wrong to see a distinction between adding variations and adding variability. Second, isolation itself does not do anything to generate new species and races, it is more a block on processes that would stop it (primarily gene flow). And thirdly - my point - without the addition of new variations, selection and drift - the processes which do change populations - would run out of material.
quote:
Thank you. Now you need to admit that this happens at least in SOME situations in the wild.
No need to thank me, since I'm saying nothing new at all. In principle it could happen, but I'm not aware of any cases of extreme selection. In the cases of cheetah and the elephant seal there was no shaping by selection that we know of, just near-extinction.
quote:
For the rest I realize I'll have to make the case better that it also occurs wherever you are getting new varieties since that's the main point of contention.
If you intend to claim that the culling associated with speciation is extreme as that associated with the creation of a new domestic variety it is not a case of making a BETTER case, since you have not made any case at all for that.
quote:
But it nevertheless provides the principle I have in mind, which I'm arguing operates wherever new varieties are being developed at a much slower and less conspicuous rate. (But slower in decades, not millennia or millions of years, and culling is still going to overwhelm the mutations at that rate).
Even Steven Jay Gould's "rapid" speciation was estimated as taking centuries in a typical case, so yes, you will have to make a case for it happening so quickly. (And, if I recall correctly - it stuck with me because it seemed counter-intuitive - the greatest rates of evolutionary change are associated with weak selection, not strong. Something else that you will have to consider).
And then again you also have to deal with the long periods of time - hundreds of millennia - between speciations. And no objecting that the time is not so long, because if you could show THAT your whole argument would be redundant.
quote:
Why, when all that happens to those mutations is that they become part of the breed or not, and the breed is still characterized by very small genetic diversity?
Because they ADD to the genetic diversity of the incipient species - contradicting your assumption that the genetic diversity must stay low.
quote:
If mutations DO add alleles or anything that gets passed on, then they get treated exactly as alleles get treated when selection and isolation create small subpopulations by culling individuals from it.
Most of them will arrive when the population is large and there is relatively little culling.
quote:
You've got your new trait (supposedly) but it's locked into a population of less genetic diversity.
So we have an increase in the diversity of the population. You may wish to ignore that fact but that does not save your argument.

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 Message 365 by Faith, posted 10-11-2013 1:17 PM Faith has not replied

  
AZPaul3
Member
Posts: 8513
From: Phoenix
Joined: 11-06-2006
Member Rating: 5.3


(2)
Message 370 of 457 (708644)
10-11-2013 3:07 PM
Reply to: Message 364 by Faith
10-11-2013 12:55 PM


Re: Environment-driven evolution
God, I hate dentists. Sadists.
If the last "species" in the ring can't breed with the first or other earlier populations, my guess would be the reason is the reduction in genetic diversity in the last one.
Your guess would be in error. The "last" link in a ring species cannot/will not breed with the first because of the built-up genetic differences that now exist between the two. Each species has now a separate history of increased genetic diversity to the point where the two have far fewer alleles in common. Both may have the same number of, say, tail-plumage alleles, but each species may have a set of unique such alleles not carried in the other. The situation is not so much that a breeding would not be successful but that sexual selection would preclude any such attempt.
Natural Selection *selects,* that is, it creates a new subpopulation of those best adapted in a particular situation. The new subpopulation is very likely to be appreciably smaller at its founding than the original just because how many adaptive alleles or other genetic influences are you going to find in any population with respect to a particular environmental challenge?
Sorry, Faith, but this is not the way NS operates. You are assuming that these fitter individuals are separated from the rest of the population they are embedded within and thus could only reproduce within this group. The way NS works is the fitter individuals create just a few more, or in extreme cases many more, offspring than the less fit members mating within the same population of available mates. This increases the number of "fitter" genomes, sets of more effective alleles, available to the population. This is the change in allele frequency we have all been talking about. Over a period of generations those "fitter" genomes with the more effective alleles may become the standard average for the population. NS has "selected" for these fitter alleles. Evolution of the population has occurred.
Edited by AZPaul3, : i wanted to

This message is a reply to:
 Message 364 by Faith, posted 10-11-2013 12:55 PM Faith has replied

Replies to this message:
 Message 371 by Faith, posted 10-11-2013 3:30 PM AZPaul3 has replied
 Message 372 by Faith, posted 10-11-2013 4:24 PM AZPaul3 has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 371 of 457 (708646)
10-11-2013 3:30 PM
Reply to: Message 370 by AZPaul3
10-11-2013 3:07 PM


Re: Environment-driven evolution
Your guess would be in error. The "last" link in a ring species cannot/will not breed with the first because of the built-up genetic differences that now exist between the two. Each species has now a separate history of increased genetic diversity to the point where the two have far fewer alleles in common.
I also expect them to have far fewer alleles in common but this is most likely because of the LOSS of genetic diversity that has attended the development of each new population around the ring. You are guessing based on the ToE and not because you KNOW the situation is as you say, and I am guessing too. We are arguing two different models or theories.
The only way this could be decided is by actually examining the DNA of the various populations. I'd expect greater homozygosity for the most characteristic traits the farther you go around the ring.
Both may have the same number of, say, tail-plumage alleles, but each species may have a set of unique such alleles not carried in the other.
I would expect them to have fewer such alleles AND unique alleles for the distinctive plumage showing up from population to population and the farther you go around the ring, as I expect there to be a loss of alleles from population to population around the ring, the distinctive plumage of each being based on the alleles that are left, or are the most high frequency in each population. They are only unique with respect to their being the basis for the particular plumage in a particular population.
The situation is not so much that a breeding would not be successful but that sexual selection would preclude any such attempt.
This is a possibility in the abstract but if the situation is as I've described it then the genetic mismatch is the more likely explanation, or at least AS likely.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 370 by AZPaul3, posted 10-11-2013 3:07 PM AZPaul3 has replied

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 Message 373 by AZPaul3, posted 10-11-2013 4:50 PM Faith has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 372 of 457 (708650)
10-11-2013 4:24 PM
Reply to: Message 370 by AZPaul3
10-11-2013 3:07 PM


Re: Environment-driven evolution
Sorry, Faith, but this is not the way NS operates. You are assuming that these fitter individuals are separated from the rest of the population they are embedded within and thus could only reproduce within this group. The way NS works is the fitter individuals create just a few more, or in extreme cases many more, offspring than the less fit members mating within the same population of available mates. This increases the number of "fitter" genomes, sets of more effective alleles, available to the population. This is the change in allele frequency we have all been talking about. Over a period of generations those "fitter" genomes with the more effective alleles may become the standard average for the population. NS has "selected" for these fitter alleles. Evolution of the population has occurred.
And it has occurred BY creating that subpopulation I was talking about. In your scenario its formation takes more time but in the end what you have is a NEW population, and yes new allele frequencies. Selection can happen faster too of course, if the selection pressure is severe. In both cases yes you have (micro)evolution, you have new allele frequencies, the unadaptive ones becoming less frequent, even dying out altogether eventually, while the adaptive ones become more frequent. And if the adaptive alleles are a much smaller number than the unadaptive ones, as I suggested will be the case, which makes sense, eventually you will have fewer alleles for the selected trait(s) than you had before (although more members of the population will possess them) as the adaptive ones will eventually replace them all, first outnumbering them and then replacing them. And that amounts to a great loss of genetic diversity over the generations it takes to fully actualize the new adapted phenotypes.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 370 by AZPaul3, posted 10-11-2013 3:07 PM AZPaul3 has replied

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 Message 374 by AZPaul3, posted 10-11-2013 5:01 PM Faith has replied

  
AZPaul3
Member
Posts: 8513
From: Phoenix
Joined: 11-06-2006
Member Rating: 5.3


(1)
Message 373 of 457 (708654)
10-11-2013 4:50 PM
Reply to: Message 371 by Faith
10-11-2013 3:30 PM


Re: Environment-driven evolution
The only way this could be decided is by actually examining the DNA of the various populations.
I would have thought you would look this up already. It's been done. Many times. After all, a ring species scenario with its ecological divergence shows us the processes of evolution that happen in deep time without having to wait. They have been studied in great detail.
This one is from the perspective of finding what indicators would appear to predict reproductive isolation. Their subjects were the various populations around a ring species. Their conclusion is that genetic divergence was a stronger predictor of reproductive isolation than ecological divergence. (Gee, really?)
Predictors for reproductive isolation in a ring species complex following genetic and ecological divergence.
In their analysis of genetic data they looked at both nuclear DNA and mitochondrial DNA. Genetic divergence from the parent population became greater the further around the ring.
Guess what? The genetic divergence seen was due to:
"new sequences nested within the clades already described for the whole species complex."
Which means new mutations of alleles that existed in the whole population, not a "loss" of alleles between the populations around the ring.

This message is a reply to:
 Message 371 by Faith, posted 10-11-2013 3:30 PM Faith has replied

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AZPaul3
Member
Posts: 8513
From: Phoenix
Joined: 11-06-2006
Member Rating: 5.3


(1)
Message 374 of 457 (708656)
10-11-2013 5:01 PM
Reply to: Message 372 by Faith
10-11-2013 4:24 PM


Re: Environment-driven evolution
And it has occurred BY creating that subpopulation I was talking about. In your scenario its formation takes more time but in the end what you have is a NEW population, and yes new allele frequencies.
No, Faith, an individual with a reproductive advantage does not constitute a "subpopulation" of the species any more than a woman with stronger leg muscles than the average constitutes a "subpopulation" of the human species.

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 Message 372 by Faith, posted 10-11-2013 4:24 PM Faith has replied

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Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 375 of 457 (708657)
10-11-2013 6:12 PM
Reply to: Message 373 by AZPaul3
10-11-2013 4:50 PM


Re: Environment-driven evolution
The only way this could be decided is by actually examining the DNA of the various populations.
I would have thought you would look this up already. It's been done. Many times. After all, a ring species scenario with its ecological divergence shows us the processes of evolution that happen in deep time without having to wait. They have been studied in great detail.
There is no point in referring me to a technical paper full of terminological mystifications. Besides which, your assumption that ring species diverge ecologically is highly questionable in my mind, certainly for some situations where there simply is no environmental divergence from population to population. Then of course your assumption that such species show "the processes of evolution that happen in deep time" is tendentious, question-begging and rife with confirmation bias. Of course if the paper were readable I'd read it and show where these errors occur in the paper itself, but I'm not sure it's readable enough for me for that purpose. I've skimmed it, saved it, and hope to check again later to see if I can answer some of it.
This one is from the perspective of finding what indicators would appear to predict reproductive isolation. Their subjects were the various populations around a ring species. Their conclusion is that genetic divergence was a stronger predictor of reproductive isolation than ecological divergence. (Gee, really?)
So far we are in agreement.
In their analysis of genetic data they looked at both nuclear DNA and mitochondrial DNA. Genetic divergence from the parent population became greater the further around the ring.
Which is exactly what I too would expect, as I've said.
Guess what? The genetic divergence seen was due to:
"new sequences nested within the clades already described for the whole species complex."
Which means new mutations of alleles that existed in the whole population, not a "loss" of alleles between the populations around the ring.
But "new sequences" in the different populations is what I would also expect, demonstrating the new high frequency alleles in the population as compared with those of the previous population. "nested within the clades" is just jargon to me so I can't make use of the concept, and "new sequences" does not suggest mutations to me, though I'm sure it does to someone with evolutionist confirmation bias.
Perhaps I'll see it differently when I try to read the paper again.

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