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Speed of Mutations and Not Natural Selection the Key

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For more than three decades, molecular evolutionists have thought that no matter how many genetic mutations show up on a specific gene, whether or not those mutations become fixed in the species is determined primarily by natural selection. The new study shows that the speed at which these new mutations arrive also affects whether the mutations become fixed. MORE

Hi eswrite, A good place to start is the following thread at ARN where Walter ReMine shares the paper he submitted related to the issue of speed limits in evolution. It was reviewed by Crow (mentioned in the above article) and Ewens, and rejected on grounds that strike me as pretty lame. It's a long thread, but Walter gives links that are worth following. In that thread I also cite portions of Ohta and Kimura's work. http://www.arn.org/ubb/ultimatebb.php/ubb/get_topic/f/24/t/000006.html Here is one of my citations " This gives a rate of nucleotide substitution per generation of at least 20, making the contrast still greater with Haldane's (1957) estimate of 1/300 per generation as the standard rate of gene substitution in evolution. Considering the amount of selective elimination that accompanies the process of gene substitution (substitutional load, see Chapter 5), the most natural interpretation is, we believe, that the majority of molecular mutations that participate in evolution are almost neutral in natural selection. Theoretical Aspects of Population Genetics by Kimuara and Ohta " The ARN thread is a classic debate between IDists and anti-IDist. The IDists will try to bring clarity to the issues, and highlight the problems, the anti-IDists try to obfuscate, derail, stress irrelevancies, put out red-herrings rather than admit these problems even exist. They try to get the discussion into an insult fest and tire out the reader into dis-interest. Somewhere in all of that, you'll hopefully see the citations Walter and I and others put forward. Kimura (Crow's student) and the neutralists are somewhat vindicated by the above study, but I then point out that the sequence divergences in "conserved regions" are not consistent with the assumptions of neutral theory. That is to say, under neutralist assumptions, the "conserved regions" should be considerably more scrambled than they are. That is the fatal flaw in the neutralist theory which the selectionists are all too happy to point out. Thus both sides (one side appealing to natural selection and the other to raw chance) find fatal flaws in each other's theories. The bottom line is: speed limits exist. What the exact speed limits are is a somewhat open issue, but the science of population genetics is ultimately not a friend of Darwinism. If fixation of single nucleotides takes on average 1/300 generations, and creatures are built with hundreds of millions of nucleotides, there is simply not enough time. That fact did not escape Crow and Kimura. And in addition to all these considerations, one must make the rather generous assumption under the selectionist view, that a selection pressure exists in the first place to fix the nucleotides. But as Bill has shown, the probabilities of such such selection pressures existing in the first place is probably more remote than just an appeal to raw chance. Salvador scordova
Bill, Do you see a possible connection between the findings in this paper and those that showed a on/off switch for accelerating mutation rates, as you reported in https://uncommondesc.wpengine.com/index.php/archives/85? eswrite
scordova, "Both the Darwinists (selectionist) camps and the neuturalist camps have found fatal flaws in each others theories. It is perhaps a bit pre-mature, but if I could hazard a guess, these developments are not good news for the Darwinists, it’s yet another devastating blow to an already bankrupt theory." Could you give me a few citations/links that I could use to see the problems with NS and genetic drift (GD) theories? eswrite
Bill, Walter ReMine, others, and myself have been predicting that Natural Selection could not be the determining factor in fixing (instilling) the majority of genetic material into all members of a population. This conclusion was a straight forward deduction from existing literature without any reference to ID, but this disturbing fact has been mostly swept under the carpet because of it's obvious anti-Darwinian implications. Such nasty problems posed by population genetics does not go unnoticed by all students of science. I have a feeling this development could be devastating. I could see it all along. For natural selection to be enforcing the conservation of billions of nucleotides is too far fetched. Natural selection can enforce and instill a limited number of nucleotides per generation (as seen with antibiotic resistance), but not large numbers of them individually. Natural selection cannot simultaneously select against large numbers of nucleotides unless it is selecting against an irreducibly complex system, but then such systems appearing in the first place pose a problem for Darwinian evolution. There is a speed limit to information fixation just like there are speed limits to modem data transfer. Natural selection is too slow of an information channel. It was blatantly obvious to Motoo Kimura (James Crow's student), but Kimura's neutral theories (sometimes called non-Darwinian evolution) has it's own set of problems. Both the Darwinists (selectionist) camps and the neuturalist camps have found fatal flaws in each others theories. It is perhaps a bit pre-mature, but if I could hazard a guess, these developments are not good news for the Darwinists, it's yet another devastating blow to an already bankrupt theory. Some IDists had seen the writing on the wall for this kind of development. I'm afraid though, the peer-reviewers, including Crow and Ewens were turning deaf ears to the IDists like Walter ReMine who foresaw these problems. scordova

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