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Author Topic:   A Guide to the tactics of Evolutionists
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 46 of 214 (366611)
11-28-2006 7:55 PM
Reply to: Message 43 by randman
11-28-2006 2:45 PM


Re: fill in the blanks
Variation, by definition increases variety. That's what variation means. Vari-ation? Vari-ety? You see how this works? When a new mutation occurs, this adds variety to the gene pool.
If the mutation is detrimental, natural selection will tend to flush it out again. If not, not.

This message is a reply to:
 Message 43 by randman, posted 11-28-2006 2:45 PM randman has replied

Replies to this message:
 Message 48 by randman, posted 11-28-2006 8:30 PM Dr Adequate has replied

Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 47 of 214 (366614)
11-28-2006 8:01 PM
Reply to: Message 45 by randman
11-28-2006 5:36 PM


Re: fill in the blanks
The point still holds on mutations in a large group being swallowed up,
Not necessarily. They can just hang around, like the various human blood types, or, if beneficial, they can be driven through the gene pool. Of course, if you have one big connected gene pool, this will displace inferior alleles. However, as you point out...
and that generally some sort of isolation of a smaller population is envisioned as the means of evolution.
... evolution may be allopatric and cladogenetic. And of course, if a species barrier has already arisen, then a beneficial mutation in one species but not another increases the divergence between the two species.

This message is a reply to:
 Message 45 by randman, posted 11-28-2006 5:36 PM randman has not replied

randman 
Suspended Member (Idle past 4898 days)
Posts: 6367
Joined: 05-26-2005


Message 48 of 214 (366636)
11-28-2006 8:30 PM
Reply to: Message 46 by Dr Adequate
11-28-2006 7:55 PM


Re: fill in the blanks
Maybe reading this article can help illustrate the issue here for you.
It was hoped that choosing wolves from across the continent would produce a population with high genetic diversity. But the new research shows this has not happened.
Isolated pockets
The researchers suggest the wolves' limited genetic variation will make them more vulnerable to factors such as disease or environmental change, limiting the pack’s ability to survive in adverse conditions.
“The species now exists in such isolated pockets that it is impossible for them to breed across the gaps, so genetic diversity will continue to fall,” Vila told New Scientist.
But Tim Wacher, from the conservation programme at the Zoological Society of London, says that it may not make any difference: “The wolves’ future could go either way - it’s possible that disease could devastate the population, but it’s also possible that the loss of genetic diversity won’t affect them."
He explains: “It was discovered recently that the genetic diversity of wild cheetahs is incredibly uniform compared to other species, but it doesn’t appear to have affected cub survival or the species as a whole.”
Wolves' genetic diversity worryingly low | New Scientist
The isolation process into smaller groups that don't breed with one another creates a marked reduction in genetic diversity. In this case, a predator, man, greatly reduced the wolf population to the point now that there is a serious reduction in genetic diversity due to the various wolf populations being separated from each other.
Note the following:
“We found a 43% drop in genetic variability in the modern wolves,” said Carles Vila, one of the team. “It is impossible for the wolf populations to recover this important diversity, which enables them to adapt to different environmental challenges."
Bears and lions
Vila notes: "It takes thousands of years of naturally occurring mutations to build up such diversity. And if the Canadian wolves - with such a large population remaining - have lost so much genetic variation, what is the situation for other endangered species in North America, such as bears or mountain lions?”
So we see that genetic diversity can and does drop very rapidly with the types of changes leading to smaller populations becoming isolated and presumably evolving (or going extinct). However, it takes thousands of years presumably for mutations to increase genetic diversity. In other words, the processes decreasing genetic diversity greatly outweigh the processes creating genetic diversity, and evos cannot account for that, and frankly, I don't think they have even tried to as far as I can tell. Rather than empirical studies, it seems evos have substituted unfounded, bald-faced assertions, and argue via semantics and definitions rather than a reasoned, empirical examination of the process they espouse.
Edited by randman, : No reason given.

This message is a reply to:
 Message 46 by Dr Adequate, posted 11-28-2006 7:55 PM Dr Adequate has replied

Replies to this message:
 Message 49 by Wounded King, posted 11-29-2006 11:04 AM randman has replied
 Message 50 by Dr Adequate, posted 11-29-2006 11:58 AM randman has replied

Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 49 of 214 (366763)
11-29-2006 11:04 AM
Reply to: Message 48 by randman
11-28-2006 8:30 PM


Going to the wolves
You assume that the degree of isolation and population reduction seen in this drastic example of a targeted reduction in the wolf population is representative of what would be required for speciation to occur, I see no evidence of that. Is there a reason you assume we should treat them as equivalent?
Vila gives a figure of 380,000 as an estimate for the historical population and the current Mexican wolf population is ~310 while that of the Canadian grey wolf is between 60-80,000. I don't know if a 50% reduction in genetic diversity is really surprising when you eradicate ~80% of the population especially if, as Vila suggests, the large remaining alaskan population would have already had a lower genetic diversity than the ancestral mexican and central US populations.
In this case, a predator, man, greatly reduced the wolf population to the point now that there is a serious reduction in genetic diversity due to the various wolf populations being separated from each other.
There is ongoing further reduction in diversity due to the small nature of the isolated populations. However there is no reason to suppose that the reason for the reduction in diversity is mostly due to the small isolated populations rather than due to the initial massive extermination of the wolves.
However, it takes thousands of years presumably for mutations to increase genetic diversity.
Care to provide some rationale for this?
Every single genetic mutation, no matter what its outcome, increases genetic diversity. Every single offspring, even from an asexual parent, is likely to represent some increase in genetic diversity, however small. It may not all be functionally relevant diversity, and it certainly may not consist substantially of beneficial mutations but it is increasing diversity none the less.
What Vila says in your article is that it takes thousands of years to build up the level of diversity seen in the pre-extermination wolf population, but this is an arbitrary amount of variation it doesn't represent any requisite level of diversity it is simply the level that happened to be extant in that particular population, a population which would certainly have had 1000s of years of extensive range and large population size in which that variation could develop.
why should it take thousands of years for any genetic diversity to develop?
The paper your article was based on 'Legacy lost: genetic variability and population size of extirpated US grey wolves (Canis lupus)' is most interesting but I don't think it really supports the contentions you are making.
TTFN,
WK
Edited by Wounded King, : No reason given.

This message is a reply to:
 Message 48 by randman, posted 11-28-2006 8:30 PM randman has replied

Replies to this message:
 Message 51 by randman, posted 11-29-2006 12:24 PM Wounded King has replied

Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 50 of 214 (366782)
11-29-2006 11:58 AM
Reply to: Message 48 by randman
11-28-2006 8:30 PM


Wolves?
Species being driven into extinction do face a loss of diversity, yes. Meanwhile the domestic wolf, or "dog", which is flourishing, displays a marked range of genetic (and morphological!) diversity.
---
Consider the following facts: we are all descended from (Y-nuclear) Adam; the Y-chromosome is not subject to sexual recombination; men have different Y-chromosomes. Where did the variety come from?
---
So we see that genetic diversity can and does drop very rapidly with the types of changes leading to smaller populations becoming isolated and presumably evolving (or going extinct). However, it takes thousands of years presumably for mutations to increase genetic diversity. In other words, the processes decreasing genetic diversity greatly outweigh the processes creating genetic diversity, and evos cannot account for that, and frankly, I don't think they have even tried to as far as I can tell.
But of course we account for it just as you do, but in less ambiguous language: where you say "The processes decreasing genetic diversity greatly outweigh the processes creating genetic diversity" as though it were a law of nature, we say "In the case of wolves, the processes decreasing genetic diversity (being driven nearly to extinction by humans, loss of habitat, loss of prey) greatly outweigh the processes increasing genetic diversity."
It would indeed take "thousands of years" to undo the damage we've done. We are living in the middle of a vast extinction event, caused by us. At present, the genetic diversity of the world is falling, because we're killing it off; but this has not always been the case.
In particular, a subgroup of a species isolated on some island did, in the past have thousands, or millions, of years to overcome the "founder effect". Darwin's finches seem quite diverse, do they not?
---
And good grief man, do you suppose that geneticists don't know about this stuff? Heck, do you suppose that the guy who did the studies refered to in the article was a creationist? Or the guy who wrote the article? We know this stuff. Look up the "50/500 rule".
Edited by Dr Adequate, : No reason given.

This message is a reply to:
 Message 48 by randman, posted 11-28-2006 8:30 PM randman has replied

Replies to this message:
 Message 52 by randman, posted 11-29-2006 12:30 PM Dr Adequate has replied

randman 
Suspended Member (Idle past 4898 days)
Posts: 6367
Joined: 05-26-2005


Message 51 of 214 (366793)
11-29-2006 12:24 PM
Reply to: Message 49 by Wounded King
11-29-2006 11:04 AM


Re: Going to the wolves
You assume that the degree of isolation and population reduction seen in this drastic example of a targeted reduction in the wolf population is representative of what would be required for speciation to occur, I see no evidence of that. Is there a reason you assume we should treat them as equivalent?
What degree of isolation do you envision? We look at the fossil record and can see remarkable examples of stasis that defie gradualistic models. We don't see large members of species gradually change at all. The evo answer is that smaller groups within a species are isolated and evolve, and their numbers being small, we don't see any fossils. So whether the parent species is as devasted over their whole range as the wolf is, or if some other factor leads to a small group becoming isolated, isn't the issue essentially the same? The smaller group has less genetic diversity.
There is ongoing further reduction in diversity due to the small nature of the isolated populations. However there is no reason to suppose that the reason for the reduction in diversity is mostly due to the small isolated populations rather than due to the initial massive extermination of the wolves.
They are the same thing. The reduction is due to the small population. The cause of the small populations being isolated is a reduction, not extinction, of the overall wolf population, but assuming some other cause of isolation, the result is the same.
But you point out indirectly another problem with evo theories. Without the parent population being devasted, it becomes hard for any new form to emerge in that ecological niche. So the idea that it is unusual in the theoritical evo process for large-scale reduction of populations is incorrect, if evo models are true.
Care to provide some rationale for this?
Just quoting the scientists in the article that said it took thousands of years for the genetic diversity to be built up.
Do you disagree with them?
The point they are making is quite plain. It took thousands of years, according to them, to build up the genetic diversity in the wolf, and less than a 100 years to greatly reduce that diversity.

This message is a reply to:
 Message 49 by Wounded King, posted 11-29-2006 11:04 AM Wounded King has replied

Replies to this message:
 Message 53 by Wounded King, posted 11-29-2006 12:55 PM randman has replied

randman 
Suspended Member (Idle past 4898 days)
Posts: 6367
Joined: 05-26-2005


Message 52 of 214 (366796)
11-29-2006 12:30 PM
Reply to: Message 50 by Dr Adequate
11-29-2006 11:58 AM


Re: Wolves?
Species being driven into extinction do face a loss of diversity, yes.
How do you think a new species can emerge if the species occupying the same ecological niche is not being driven to extinction? Moreover, isn't it fairly normal for species to be driven to extinction over time? Are you suppossing that extinction is not part of the process of evolution?
As to the rest of your post, I am not sure what relevant points you are trying to make. Do evos know that they have never properly substantiated the fact that forces decreasing genetic diversity outweigh forces increasing genetic diversity?
I don't know.
Heck, as an undergrad in the 80s, I knew that Haeckel's stuff was forged and there was no phylotypic stage, but plenty of evo scientists in that field kept insisting on a phylotypic stage and references Haeckel's stuff as well.
Did they know, or were they just ignorant?
very good question.....wish I knew the answer

This message is a reply to:
 Message 50 by Dr Adequate, posted 11-29-2006 11:58 AM Dr Adequate has replied

Replies to this message:
 Message 56 by Dr Adequate, posted 11-29-2006 3:38 PM randman has replied
 Message 69 by mick, posted 12-01-2006 1:14 PM randman has replied

Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 53 of 214 (366805)
11-29-2006 12:55 PM
Reply to: Message 51 by randman
11-29-2006 12:24 PM


Re: Going to the wolves
The smaller group has less genetic diversity.
Probably, but the extent of the reduction need not be as drastic as the 50% in the Vila study. If the extermination had been of the less genetically diverse historical Canadian population and the more genetically diverse central population of C.l.nubilus had survived they might have only seen the loss of ~4 haplotypes.
It certainly isn't guaranteed that the loss of diversity would ensure a failure to thrive of the population and subsequent further reductions in diversity, nor that regaining an equivalent amount of diversity would require thousands of years.
Without the parent population being devasted, it becomes hard for any new form to emerge in that ecological niche.
Only if you insist on sympatric speciation (speciation within a single population) rather than allopatric (two populations are geographically isolated) or parapatric (Populations are contiguous but with restricted gene flow due to differential success in differing environments). If you look at the diversification of Cichlid's in lake Victoria you will see that rather than all fighting for the same niche they have diversified to fill many different niches, this diversification probably encompasses more than one of the categories above (Kocher, 2004; Won et al., 2005).
Do you disagree with them?
Not at all, but that isn't what you said. You went from the specific case of wolves to making a general argument that 'it takes thousands of years presumably for mutations to increase genetic diversity'. If you are only talking about the current wolf population in North America that is fine, but you seemed to be applying it more broadly.
TTFN,
WK

This message is a reply to:
 Message 51 by randman, posted 11-29-2006 12:24 PM randman has replied

Replies to this message:
 Message 54 by randman, posted 11-29-2006 1:03 PM Wounded King has replied
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randman 
Suspended Member (Idle past 4898 days)
Posts: 6367
Joined: 05-26-2005


Message 54 of 214 (366812)
11-29-2006 1:03 PM
Reply to: Message 53 by Wounded King
11-29-2006 12:55 PM


Re: Going to the wolves
It certainly isn't guaranteed that the loss of diversity would ensure a failure to thrive of the population
Whether the population thrives is not the point really. Cheetahs thrived for a long time with a narrow range of genetic diversity. The point is the process creates less genetic diversity, not more.

This message is a reply to:
 Message 53 by Wounded King, posted 11-29-2006 12:55 PM Wounded King has replied

Replies to this message:
 Message 55 by Dr Adequate, posted 11-29-2006 3:30 PM randman has not replied
 Message 65 by Wounded King, posted 11-30-2006 5:33 AM randman has replied

Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 55 of 214 (366878)
11-29-2006 3:30 PM
Reply to: Message 54 by randman
11-29-2006 1:03 PM


Re: Going to the wolves
Whether the population thrives is not the point really. Cheetahs thrived for a long time with a narrow range of genetic diversity. The point is the process creates less genetic diversity, not more.
When "the process" involves being driven nearly to extinction by one of the greatest extinction events of all time, then yes, this does reduce genetic diversity.
The dodo, for example, now exhibits no genetic diversity whatsoever.
Edited by Dr Adequate, : No reason given.

This message is a reply to:
 Message 54 by randman, posted 11-29-2006 1:03 PM randman has not replied

Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 56 of 214 (366883)
11-29-2006 3:38 PM
Reply to: Message 52 by randman
11-29-2006 12:30 PM


Re: Wolves?
How do you think a new species can emerge if the species occupying the same ecological niche is not being driven to extinction?
It can, for example, colonize an unoccupied niche.
Moreover, isn't it fairly normal for species to be driven to extinction over time? Are you suppossing that extinction is not part of the process of evolution?
Yes; and no, respectively.
As to the rest of your post, I am not sure what relevant points you are trying to make. Do evos know that they have never properly substantiated the fact that forces decreasing genetic diversity outweigh forces increasing genetic diversity?
I would agree that this claim has not been substantiated; but you are the one who is making it. So far, your only attempt to substantiate it has been to conflate the extinction event now ongoing with the general course of nature.
I notice you have not commented on the Y-chromosome. Why not?
Heck, as an undergrad in the 80s, I knew that Haeckel's stuff was forged and there was no phylotypic stage, but plenty of evo scientists in that field kept insisting on a phylotypic stage and references Haeckel's stuff as well.
But you cannot quote them, because ... ?

This message is a reply to:
 Message 52 by randman, posted 11-29-2006 12:30 PM randman has replied

Replies to this message:
 Message 57 by randman, posted 11-29-2006 7:09 PM Dr Adequate has replied
 Message 58 by randman, posted 11-29-2006 7:12 PM Dr Adequate has replied

randman 
Suspended Member (Idle past 4898 days)
Posts: 6367
Joined: 05-26-2005


Message 57 of 214 (366950)
11-29-2006 7:09 PM
Reply to: Message 56 by Dr Adequate
11-29-2006 3:38 PM


Re: Wolves?
It can, for example, colonize an unoccupied niche.
Imagination is great, isn't it? So a species just a teeny bit different than another species is going to replace it, but the first doesn't go extinct. Keep in mind colonizing an unoccupied niche most likely involves a different geography or something like that, and so once again there is isolation of a smalller group involved, not the whole-sale replacement of a near identical group over and over again with very small changes adding up to whole new types of creatures.
Yes; and no, respectively.
So you don't consider extinction of older species via natural selection a part of the evo model?
I would agree that this claim has not been substantiated; but you are the one who is making it.
Wrong, it's not real science to posit something and say, well, no one has disproven it so it must be so. That's what evos do though, and so it's not real science. Evos have a claim that small-scale changes add up to macroevolution, but they have not substantiated it, as you admit.
Had they substantiated it, they would have to show that the observed forces limiting genetic diversity is less than the mostly unobserved forces supposedly increasing it.
Where are the peer-reviewed studies showing these things, Dr Adequate?
Where are the evo studies showing that small-scale changes can add up to macroevolution even when the process limits genetic diversity?
Just saying, hey, this is the way it is, and you have to show why it cannot, is not sufficient. To be empirical-based science, you have to show it, and evos have not for this most basic claim of their's.
Conclusion: it's not empirical-based science but faith-based assertions, and dogmatic assertions at that.

This message is a reply to:
 Message 56 by Dr Adequate, posted 11-29-2006 3:38 PM Dr Adequate has replied

Replies to this message:
 Message 59 by Dr Adequate, posted 11-29-2006 11:50 PM randman has replied

randman 
Suspended Member (Idle past 4898 days)
Posts: 6367
Joined: 05-26-2005


Message 58 of 214 (366953)
11-29-2006 7:12 PM
Reply to: Message 56 by Dr Adequate
11-29-2006 3:38 PM


Re: Wolves?
But you cannot quote them, because ... ?
First off, the Richardson study in 1997 states that the phylotypic stage and Haeckel's data were widely accepted and used both in textbooks and in peer-reviewed literature. You obviously want to waste everyone's time not looking up the details of the debate, something debated here ad nauseum by the way.
I suggest you do your own homework.

This message is a reply to:
 Message 56 by Dr Adequate, posted 11-29-2006 3:38 PM Dr Adequate has replied

Replies to this message:
 Message 60 by Dr Adequate, posted 11-29-2006 11:58 PM randman has not replied

Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 59 of 214 (367013)
11-29-2006 11:50 PM
Reply to: Message 57 by randman
11-29-2006 7:09 PM


Re: Wolves?
Imagination is great, isn't it? So a species just a teeny bit different than another species is going to replace it, but the first doesn't go extinct. Keep in mind colonizing an unoccupied niche most likely involves a different geography or something like that, and so once again there is isolation of a smalller group involved, not the whole-sale replacement of a near identical group over and over again with very small changes adding up to whole new types of creatures.
What do you think you're replying to?
So you don't consider extinction of older species via natural selection a part of the evo model?
Yes. I do. I said so. What do you think you're replying to?
Wrong, it's not real science to posit something and say, well, no one has disproven it so it must be so.
What do you think you're replying to?
Evos have a claim that small-scale changes add up to macroevolution, but they have not substantiated it, as you admit.
Had they substantiated it, they would have to show that the observed forces limiting genetic diversity is less than the mostly unobserved forces supposedly increasing it.
Where are the peer-reviewed studies showing these things, Dr Adequate?
Where are the evo studies showing that small-scale changes can add up to macroevolution even when the process limits genetic diversity?
Just saying, hey, this is the way it is, and you have to show why it cannot, is not sufficient. To be empirical-based science, you have to show it, and evos have not for this most basic claim of their's.
Conclusion: it's not empirical-based science but faith-based assertions, and dogmatic assertions at that.
See my comments on the Y-chromosome. To which I have drawn your attention more than once.
Edited by Dr Adequate, : No reason given.

This message is a reply to:
 Message 57 by randman, posted 11-29-2006 7:09 PM randman has replied

Replies to this message:
 Message 61 by randman, posted 11-30-2006 12:13 AM Dr Adequate has replied

Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 60 of 214 (367014)
11-29-2006 11:58 PM
Reply to: Message 58 by randman
11-29-2006 7:12 PM


I suggest you do your own homework.
It is now part of my homework to substantiate your arguments?
How very convenient for you.

This message is a reply to:
 Message 58 by randman, posted 11-29-2006 7:12 PM randman has not replied

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