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Author Topic:   The End of Evolution By Means of Natural Selection
Faith 
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From: Nevada, USA
Joined: 10-06-2001


Message 325 of 851 (555179)
04-12-2010 3:04 PM
Reply to: Message 322 by Taq
04-12-2010 2:49 PM


Re: ring species genotypes are different
But despite evidence galore that these mistakes have produced thousands of genetic diseases in human beings as well as apparently only incoherent effects otherwise --that only destroy a previously functioning allele -- you all PRONOUNCE them the means of making functioning alleles (functioning meaning producing something coherent that isn't harmful) and then you call it FACT and talk as if every variation is the result of mutations -- you actually DESCRIBE variations as mutations -- and again, this is DECEIT.
According to this logic we should find the exact same gene in every species, down to the base. Is this correct? Afterall, any deviation will result in disease, right?
Huh? NO idea where you get this out of what I said.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 328 of 851 (555183)
04-12-2010 3:13 PM
Reply to: Message 326 by hotjer
04-12-2010 3:07 PM


Re: changing debaters
Cognitive dissonance is what I experience here on a routine basis.
I think that sums it up, unless we assert this occur ultimately to 99,99% of all scientists on this specific subject and not to you.
Argument from authority, pulling rank, another typical way to dismiss the evidence.
Most creationist scientists don't agree with the evolutionists and an ordinary intelligent person ought to be able to recognize the problem with treating a mere assumption as if it were a fact. They just don't get the chance. You call it a fact so they believe you, poor things. I too have found it hard to believe that evolutionist scientists are this easily self-deluded, but unfortunately they are.
Edited by Faith, : No reason given.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 330 of 851 (555187)
04-12-2010 3:22 PM
Reply to: Message 327 by DevilsAdvocate
04-12-2010 3:13 PM


Faith writes:
What is actually SEEN is better explained on the basis of pre-existing alleles.
What pre-existing alleles? What are you talking about?
All those you see when you sequence DNA. LOTS of them.
What reference are you using to determine if an allele, a trait, or whatever other genetic terminology is normal or not.
If it produces a normal trait. You know, something like green eyes or calico fur.
The term 'normal' can be used in many context.
Do tell, and you can be sure that evolutionists will use it to describe abnormal events like mistakes in DNA duplication among others.
Mutational changes at the DNA is not one of them since mutations have been occuring throughout the life tree for millions of years.
And you have no idea that this is merely an assumption and not a fact, do you?
There is no way to judge what is 'normal' and what is not 'normal' at this level. All we can do is use preceding genomes to determine what changes have been made.
I'd be happy if you'd just start by looking at the sequences of the genomes of that family Bluejay linked to on the other thread, and see if any of the 70 mutations that were found actually code for anything useful.
You have NO evidence that a normal allele was ever created by mutation.
That is because no one is claming that a 'normal' allele is created by mutation and no geneticist uses your convaluted and contrived terminology.
That's right, they have no terminology for what is REALLY going on because they're besotted by evolutionism and ASSUME it in everything they do -- when you do that you insulate yourself from any information that might falsify the assumption -- and that includes the ridiculous assumption that normal functioning alleles are produced by a process that is ACTUALLY known ONLY to produce mistakes, disease, nonfunction and so on....
except in bacteria, since they need their beneficial mutations to kill off the rest of creation. (no junk DNA = lots of genetic potentials lost to most of the rest of creation)
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 366 of 851 (556015)
04-16-2010 5:44 PM
Reply to: Message 362 by nwr
04-16-2010 4:25 PM


dominance
Surely genetic dominance does confer some population dominance too.
If there is no reproductive advantage then all the rabbits will pass on their alleles equally, and that means that whenever the dominant allele for black fur combines with the alleles for any other color, black fur will show up in the majority of combinations possible.
parents --------------- offspring
BB + gg (grey) will get 4 Bg, all black
BB + tt (tan) = 4 Bt, all black
BB + bb (brown) = 4 Bb, all black
Next generation all the heterozygous B's also pass on their blackness, Bt + Bt = BB, Bt, Bt, tt = three blacks and a tan, though Bt with tt = Bt, Bt, tt, tt = two blacks and two tans for a standoff. Meanwhile the homozygous blacks, BB, are still mating with the homozygous tans, greys and browns and repeating the same distribution of the first generation. And of course all the other colors are combining and increasing their own number according to their relative dominance. But over time the black SHOULD come to dominate.
It would be quite a project to work it all through with the hierarchy of dominance specified, but since black is dominant over all the others it seems pretty clear that eventually black should come to dominate the whole population, all other things being equal.
If not, why not?
(I don't think this has anything to do with what I'm trying to prove, but it's interesting -- hm, correction, it's relevant since I've had to take this into account myself but it isn't going to defeat my model is what I really mean. A population could conceivably reach the point where it's all black with mostly BBs but a few Bt's, Bg's and Bb's, or even a complete lack of the alleles for any of them, so that in a migration it could happen that all the heterozygous ones get swept along leaving the parent population all BB. If some BB's also come along in the migration black may yet come to dominate there too but meanwhile the recessives will be liberated so that it will start getting the other colors as well as the black.
ABE: After the rest of the discussion here I realize the black won't come to dominate without reproductive advantage of some sort (and in fact that was my very first response to Zen Monkey on the other thread when he raised this question), but it is true that all the other colors will now show up in the new population that were suppressed by the dominant black in the parent population (by drift of course in that situation).
ABE: AND, it doesn't have to have been a dominant that had such a high frequency in the parent population. The genetically dominant black could have been the one suppressed that then could have been taken into the new population where it would probably already be of a higher frequency than in the first population.
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.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 369 of 851 (556021)
04-16-2010 6:11 PM
Reply to: Message 367 by PaulK
04-16-2010 6:01 PM


Re: dominance
Unfortunately I can't stay around for this until later but please indicate which post of yours you are referring to. Thanks.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 371 of 851 (556025)
04-16-2010 6:18 PM
Reply to: Message 361 by ZenMonkey
04-16-2010 4:09 PM


Re: Restoration of diminished alleles.
Far as I can see, you are right. I did it with alleles instead of colors and now notice that it works out the same as what you did.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 374 of 851 (556038)
04-16-2010 7:58 PM
Reply to: Message 372 by nwr
04-16-2010 6:56 PM


Re: dominance
Next generation all the heterozygous B's also pass on their blackness, ...
Actually, no, they don't. If two heterozygous Bs mate, then 1/4 of their offspring will have no B allele. That's the expected statistical outcome, though a particular mating pair might happen to have a different distribution.
That's exactly what I said in the rest of that sentence, here:
Next generation all the heterozygous B's also pass on their blackness, Bt + Bt = BB, Bt, Bt, tt = three blacks and a tan,
However, I've worked it through and I see that you are all right, the dominants will not change their proportion barring reproductive advantage, they will retain the same proportion through all generations, which is greater than the others, but always the same proportion greater. That is "some population dominance," as I said also -- meaning there will always be more black rabbits than the other three colors, and more browns than greys and tans, and more greys than tans, barring any kind of selecting factor -- but they will not increase in proportion.
But I just realized Zen Monkey is not starting with equal numbers as I am. He's starting with a population in which the dominant blacks have been sharply diminished in number. But the same principle must apply.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 377 of 851 (556042)
04-16-2010 8:20 PM
Reply to: Message 375 by nwr
04-16-2010 8:10 PM


Re: dominance
There can still be less blacks than the other colors.
I don't see how if black is dominant to all the others, brown is dominant to grey and grey is dominant to tan. If there is no reproductive advantage operating at all then they should sort themselves into a descending order of proportions from black to tan more or less as Zen Monkey laid it out.
But of course,
"due to the dominance, the proportion of blacks in the population will be greater than the proportion of black alleles in the gene pool"
as you said.
Edited by Faith, : No reason given.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 378 of 851 (556043)
04-16-2010 8:24 PM
Reply to: Message 376 by RAZD
04-16-2010 8:18 PM


Re: dominance vs hidden alleles
Hold that thought and savor it. Dominance of a neutral allele is unrelated to it's selection (because it is neutral).
I don't believe I've made that mistake. RAZD.
Perhaps then we can relate this to your concept of hidden alleles that emerge in small populations ... presumably because other alleles that have kept it hidden are lost.
I described such a situation a few posts above, which I just sharpened up by edit based on this discussion -- bottom of Message 366.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 380 of 851 (556045)
04-16-2010 8:34 PM
Reply to: Message 379 by nwr
04-16-2010 8:27 PM


Re: dominance
Well, yes, of course, and I've been working with that kind of example myself in my argument, but in this case I was trying to stick with a "perfectly" proportioned population because I thought that was what Zen Monkey was doing.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 388 of 851 (556070)
04-17-2010 1:07 AM
Reply to: Message 384 by RAZD
04-16-2010 10:56 PM


Re: dominance vs hidden alleles
ABE: After the rest of the discussion here I realize the black won't come to dominate without reproductive advantage of some sort (and in fact that was my very first response to Zen Monkey on the other thread when he raised this question), but it is true that all the other colors will now show up in the new population that were suppressed by the dominant black in the parent population (by drift of course in that situation).
Except that your supposed hidden alleles were never seen in previous populations, and this does not fit with the patterns above.
RAZD, you seem to be making up my side of the argument for me.
I've given many different examples over the thread. The example I was giving above, using Zen Monkey's hierarchy of fur colors, was of a population in which black had come to so completely dominate through drift or some kind of selection process that the expression of a homozygous recessive just about never happened because it would be that rare in a very large population of predominantly BBs for the pairings to occur -- and the BBs are so prevalent BECAUSE black has been severely selected. The others might of course still occur. But the point is that in a migration to start a smaller daughter population it could happen that you'd get enough of the heterozygous blacks to increase their frequencies relative to the BBs and that would allow the other colors to be expressed far more than in the parent population. It's a really simple example, simply another example how it IS the change in gene frequencies alone that changes the phenotype for the new population without any addition of mutations.
Whatever happened to the definition of evolution as change in gene frequencies anyway? This supposedly describes what happens through selection or drift or migration -- you shouldn't need mutations to get a new character to a new population.
{ABE: My argument, just for a reminder, is that it is the SELECTION processes -- including drift and migration and so on -- that change the frequencies, and dominant and recessive alleles come into play as a way of explaining how under selection some traits could completely disappear from a population or at least become extremely rare and then start showing up in greater numbers in a daughter population.
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.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 391 of 851 (556073)
04-17-2010 2:04 AM
Reply to: Message 388 by Faith
04-17-2010 1:07 AM


Re: dominance vs hidden alleles
Just read through this discussion of budgie breeds.
http://www.bestofbreeds.net/al-nasser/article9.htm
Mutation is assumed in a couple of instances but mostly it's a complicated discussion of how you get different traits from combinations of dominants and recessives. Without grasping all the particulars, I'd say this suggests that in the wild if birds migrate away from a parent population to set up new populations you could easily get many new types of bird populations just from the built-in alleles.
This is the sort of thing I was thinking of for examples like the greenish warblers RAZD brought up. Many possible combinations means any random selection force such as geographic isolation would bring out all kinds of new expressions.
So should we say the new traits had been previously "hidden" or what?
If the new population stays reproductively isolated then there's no reason their own peculiar characteristics couldn't become fixed and come to define a new species, thanks to mere isolation of a portion of a population from the parent population, a form of random selection. This has to be a process of genetic reduction not addition simply because the migration has taken a small number out of a large number to get the new effect.
And yes, again, you could still have enough diversity for further population splits with the creation of yet new varieties. But the trend is always to reduction. Any given path of variation -- any particular bird variety -- has to have an end point beyond which further variation can't happen. It's the perfect expression of its particular complement of alleles and there aren't any "extras" left as it were, for making new varieties.
I guess I'm repeating myself again. Seems so clear to me.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 393 of 851 (556081)
04-17-2010 5:26 AM
Reply to: Message 143 by Percy
03-31-2010 7:22 AM


Re: Why Allele Subsets do not a Species Make
Catching up on some earlier posts.
Assume a population has 26 genes labeled a-z.
Further assume that each gene has 4 alleles labeled a1-a4, b1-b4, and so forth.
An earthquake occurs that causes a river to change course, and a subpopulation becomes trapped on land that is now an island. This population only has the first two alleles of each gene, a1-a2, b1-b2, and so forth.
If this alone were sufficient for speciation, then you should be able to list a combination of specific alleles that could form in the subpopulation but not in the main population.
OK, that's an interesting way to lay it out, but immediate speciation isn't required by my model. I think I can easily enough list a combination for the subpopulation, at least, that should demonstrate how it can get a dramatic difference in phenotypes by taking some and leaving others behind:
Let a daughter population be formed from individuals carrying anywhere from 1% to 40% of a-1 &3, b-1, c-4 (a single allele would have to come from individuals homozygous for this trait), d-1 & 2, e-2, f-3& 4, g-1&4, h-1,2,3&4, i-1, 2, 3& 4, j-3, k-4, l-2,3, m-1,4 and so on randomly through z, plus maybe 90% of, oh, m-4. That is, SOME of the alleles are taken from the parent population, only 1 for some of the genes, but up to all 4 for others, and if the daughter population is very much smaller it may not deprive the parent population of a single allele so it will go on with more or less its usual gene frequencies. The daughter population, however, is going to have a completely different mix and will develop a different appearance for that reason.
And since it's smaller and it's left more alleles behind than it took it's clearly in a condition of reduced genetic diversity compared to the parent population.
But I've never claimed that such a situation would lead to speciation. I take speciation to be usually the end product of many selection processes, although I do recognize that reproductive isolation can occur long before variability has run out.
How are you going to do that, given that every allele in the subpopulation exists in the main population? For example, try this one:
a1b2c1d2e1f2g1h2i1j2k1l2m1n2o1p2q1r2s1t2u1v2w1x2y1z2
There's not a single allele in that list that doesn't exist in the main population. No matter how you mix and match alleles in this subpopulation, it is impossible to come up with a combination that couldn't happen in the main population.
Well, if the population is not extremely large you could sharply reduce the number of alleles for any given gene by their being taken with the migrating subpopulation, say along with the 90% of m-4 also 80% of n-1, 70% of o-2 & 90% of p-3, and 100% of q-3 and r-2. The high percentages gone would at least make some combinations far less likely though not impossible, but missing 100% of all the individuals that possess a particular allele will make combinations with that one definitely impossible.
That's why allele reduction does not result in speciation.
Eventually it will as the processes that select and isolate continue to work. Speciation is brought about by various forms of population splitting, generally a smaller part of a parent population becoming a daughter population, according to many sources I've found, as shown in this little chart at Wikipedia:
File:Speciation modes.svg - Wikipedia
The smaller populations are formed through different circumstances but their composition is the same in all cases -- made up of a portion of the alleles of the parent population.
Edited by Faith, : No reason given.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 397 of 851 (556117)
04-17-2010 1:19 PM
Reply to: Message 394 by nwr
04-17-2010 8:07 AM


Re: dominance vs hidden alleles
Mutation is assumed in a couple of instances but mostly it's a complicated discussion of how you get different traits from combinations of dominants and recessives.
The fact that mutation is only mentioned a few times does not show that there were not other mutations. The breeders would be mainly concerned with mutations with visible traits that might be attractive to bird owners. They would not notice mutations that did not cause visible changes.
I don't think it affects my point if there are other mutations since they act like the alleles I'm talking about in any case.
Faith writes:
Without grasping all the particulars, I'd say this suggests that in the wild if birds migrate away from a parent population to set up new populations you could easily get many new types of bird populations just from the built-in alleles.
Yes, but they wouldn't be considered a separate species unless there were further divergence from the original group.
Seems to me 1) this process produces some very striking divergence and 2) descriptions of new species don't make them sound like much more than the same species with some striking new characteristics.
Incredible Batch of Rare and New Species Discovered - Science and Nature LiveJournal
http://animal.discovery.com/...images/red-eyed-tree-frog.jpg
Built-in alleles in new combinations thanks to isolations of part of the gene pool explain it fine I think. But it doesn't really change anything in my model here to assume they are mutations either.
Maybe a mutation allows them to feed on a tougher seed than before, and because that tougher seed is abundant in the new environment you get strong selection pressure to favor the new mutation.
OK, you want to insist on mutations, though the descriptions could just as well apply to new combinations of built-in alleles as to mutations so I see no need for mutations -- AND the mutations are as usual assumed and not known for a fact to be the source of any given novelty -- but for my purposes I don't really think it matters because the processes that select and isolate and reduce genetic diversity will operate on both just the same.
Faith writes:
Mutation is assumed in a couple of instances but mostly it's a complicated discussion of how you get different traits from combinations of dominants and recessives.
The fact that mutation is only mentioned a few times does not show that there were not other mutations.
True, but my mention of their reference to mutation was only in passing and what's interesting to me about that article is the complicated changes that different combinations of dominants and recessives can produce, which even in the wild with population splits could produce quite a range of new varieties.
Again, it is apparent that whenever mutations are invoked it is an assumption that usually isn't proved. A new trait emerges, it's called a mutation, it's assumed. Sometimes the gene can be pinpointed and the change accounted for as a mutation, but the theory that all alleles come from such changes isn't proved by that, still merely assumed.
If mutations happen to be occurring more frequently now than in the past, and they are accidents or mistakes that sometimes produce something neutral that can be regarded as desirable, such as by breeders, but couldn't have produced all alleles, how could this be known? The changes all occur on a strand of alternating chemicals, so by chance sometimes a useful combination could result even by accident, but if that's all there is to mutations seems most probable that the disease-producing mutations would have wiped out all living things long before anything functional could come up.
But I didn't want to stay in the conversation about mutations right now. Even if they do occur and account for the material for variation (really, I nearly choke saying that because I'm so convinced it doesn't happen except possibly very rarely) but even if they do, the processes of selection and isolation that bring out new characteristics for new populations still reduce the genetic diversity in producing these new varieties no matter what its original source.
===========
I don't know what happened in this post. It appears that your post got duplicated and I answered parts of it twice. But I don't think I'm too terribly repetitive and it would be very hard to rewrite it so I'll just leave it.

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Faith 
Suspended Member (Idle past 1704 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 398 of 851 (556120)
04-17-2010 1:35 PM
Reply to: Message 396 by Percy
04-17-2010 8:47 AM


Re: Why Allele Subsets do not a Species Make
The scenario you describe, where both parent and daughter populations lose alleles through many generations such that the parent population comes to have alleles the daughter population does not have, and the daughter population comes to have alleles the parent population does not have, seems like it could produce speciation if it ever really happened.
Seems to me that if only the daughter population changes it would also lead to speciation.
And I don't see why it couldn't happen since it is produced by a simple migration of a small portion of a population away from the rest, and it does fit that little diagram from Wikipedia that I posted showing the different types of speciation.
But the differences between the parent and daughter populations with regard to which alleles they possess is also heavily influenced by mutation. Whether you believe in beneficial mutations or not, every offspring has mutations that result in a unique allele or two (a reasonable average figure that's in the ballpark) not seen before in the species.
It doesn't change the processes I'm trying to focus on if you want to assume that. Even if the changes are produced by mutations it still takes the selecting and isolating to bring them out and form a new characteristic phenotype for a new population. Such mutations could simply stay in the population without such processes operating but that wouldn't produce a new variation or species, simply a population with high variability.
Consider the population of rabbits in Australia (a population of millions and millions of rabbits). Each year millions and millions of baby rabbits are produced, and each one has on average one new allele. This means that each generation of rabbits gets millions and millions of new alleles. Given that reproduction is almost never perfect, this is inevitable. It isn't a case of whether it happens. It's a case of how you would ever stop it.
OK, such mutations occur, but as long as you can't tell what those alleles are actually doing, whether they are actually the source of a new variety for instance, they could still best be regarded as a pathological event. But again, assuming they do produce new viable traits, you still have to select and isolate them to get a new variety or species, which reduces the genetic diversity for the new population, and when that happens the majority of the millions are reproductively cut off so that the new population with the new characteristics can emerge -- because of its reduced genetic diversity.
Edited by Faith, : No reason given.

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