If evolution just means change, then the opposite would be no change. The absence of change.
Read the following John:
And you still seem to be suffering from the same misunderstanding that “less fit” alleles cannot spread through the population by genetic drift.
if “less fit” alleles can spread, then it is not the case that " the alleles were not less fit" is “the” answer.
That still doesn’t make sense given the fact that YEC’s accept natural selection. Deleterious mutations would be selected against and conserve the “absolute perfection”.
Read it. You seem to completely misunderstand the point. What you say about fixation of deleterious alleles is true, but it’s off-topic. Behe isn’t talking about deleterious alleles at all.
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Are you familiar with Müller’s ratchet?
I am, and it is very relevant to this discussion. Most of my comments were related to sexually reproducing organisms which escape some (most?) of the effects of Muller’s ratchet, but Muller’s ratchet can certainly have strong effects on population genetics. It is interesting to note that there appears to be a limit to Muller’s ratchet imposed by negative selection, as seen in some endosymbionts:
Feel free to point to any mistakes I am making in relation to population genetics.
Your mistake is the claim that deleterious mutations can’t become fixed. Of course they can, with a probability inversely related to population size and directly related to selection coefficient, and this is Mung’s handle on which he hangs his snark. And I will point out once again that this whole subject relies on a misreading (though a forgiveable one) of @NLENTS’s summary of Behe. Behe wasn’t talking about deleterious mutations at all.
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Fair enough. I also discussed probabilities, with deleterious mutations having a lower probability of becoming fixed. Even that is inaccurate in all cases since there are scenarios you pointed to where the probabilities could be the same. Most of my comments have been vague generalities, but you have rightly pointed out the importance of the specifics.
Also a good point. We will see how the rest of the chapters shape up.
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It doesn’t matter whether they are deleterious. And T_aquaticus was talking about deleterious alleles. Perhaps he should have read Behe before launching his ill-considered “gotcha.”
So what you’re saying is that you were just trying to score a cheap point.
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You are right. I wasn’t careful enough in my reading of what Behe was talking about. Now we will see how the rest of the book shapes up.
Nice try, but T_aquaticus piped up before Nathan said anything.
The “cheap point” being that he didn’t understand genetic drift? If only you were so forgiving of IDists and Creationists who don’t understand basic elements of evolution.
So he did. The original misreading was of @AndyWalsh, not @NLENTS. You get another point! Winning!
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Isn’t that central to Behe’s thesis?
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No. Once again: Behe was talking about loss-of-function mutations that are advantageous in some particular environment.
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But are they LOF? We’re talking about the 9 fixed mutant APOB alleles in the polar bear, correct?
That, or at least reduced function, is Behe’s claim as far as I can see. Evolution can only break stuff, and sometimes breaking stuff is advantageous.
But all the circumstantial evidence points to gain of function for those alleles.
That is correct. It is very puzzling to see him dismiss this as evidence against evolution of new function.
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