Molecular Population Genetics and Diversity through Mutation

That's probably not a correct statement.Phenotype - Wikipedia I think a better way of dealing with things is to note that Faith really means genetic diversity as only the loss of genetic diversity can really count as a permanent loss to a population. Of course mutations directly add to genetic diversity. Faith's responses to that fact are total nonsense. But she will never see that regardless of how much rigorous your math is.Edited by NoNukes, : No reason given.

I agree with the tanning example, but I think we can come up with something more significant than something that comes and goes with exposure to the sun. I am struggling to come up with examples, but maybe the development of allergies based on exposure to some irritant might be something that does not fade away immediately, or perhaps an exposure to some chemical in the environment that suppresses the immune system.I am not sure what the Wikipedia article was getting at, but I don't want the impression to be that all examples are as trivial as tanning. Perhaps my examples are not good ones.

Epigenetic functions are specifically factors that switch gene expression on or off. I am not sure that this covers every possible every possible environmental mechanism, but perhaps I am wrong. I appreciate that you've added novel allele combinations. I think it is important to do so because that addition is the closest to things that Faith is claiming are the 'real' mechanisms for new phenotypes.I'm satisfied with your position.

I would add that the only reason for this is that there are so many other loci available that it is only unlikely that the an immediately previous one generated again in a random process. There is no natural equivalent of a 'breeder' working to prevent any old allele to come back. If in fact, we got to a point where a large percentage of loci had been mutated in an evolutionary branch, we should expect to start seeing some reruns.

Duplicate. produced in part by glitch when submitting response.Edited by NoNukes, : No reason given.

Your statements about what must have happened ignore the effect of selection. That is a strange thing for you to ignore. It is not just the geographic isolation from other populations that is available to favor beak development. In fact it is not clear that such things play a roll at all. It is primarily, and more importantly, observably, the competition for food or other necessity that weeds out birds who cannot cope as well as other birds with the situation in a new environment. According to your theory it would be mere accident, and completely inexplicable that the new allele frequencies just happen to correspond to advantages in the environment. One might anticipate that in the new situation beaks might get smaller or remain the same if sampling was random. On the other hand, natural selection driving which birds prosper explains the situation extremely well.In my opinion, and in any objective view as well, that is an example of reality supporting one proposition and not supporting the other. Such support is not proof, but it is evidence and it cannot be claimed that the evidence supports both your proposition and the theory of evolution equally well.Whether or not you personally believe in natural selection, you are not going to be able to assume it away without evidence if you want to be convincing.I believe you are at least partially right about variation. Mutation rarely plays a role during the selection process. Darwin neither recognized, nor observed mutation in action. It would be just as coincidental and unbelievable that mutation showed up 'just in time' to be useful in a new environment as it would be that mere resampling produced anything useful in nature. On the other hand, the theory of evolution is in total agreement with that. The real story according to the TOE is that essentially all of the genetic variation that lies behind the phenotypes that are screened for in a selection process is produced randomly by mutation.Darwin did in fact observe variation in phenotype within the parent population, something which completely disabuses the idea that variation prevents forming a subspecies. The idea is silly anyway. One only need look at the cosmetic and genetic variations among people of one race to observe that there is plenty of room for both genetic and phenotypic variability without having individuals being kicked out of their race.While we are focusing now on the founders effect, let's recall that evolution and changes of gene frequency are observed in situations where there is no isolation at all, but there are environmental changes and it is quite clear that the reasons for the change in population is driven by some animals simply not surviving to produce offspring due to competition.

I'm a bit suspicious of this idea. Sometimes populations do not intermingle thoroughly even over large periods of time. For example there are large segments of the US human population that have historically resisted intermingling due to social circumstances despite the fact that they are inter-fertile, and accordingly I would not expect some alleles not to be evenly distributed through out the population. I suspect we can find examples of animal populations behaving similarly.But I have to admit that no additional examples comes to mind. What we can say is that distributing a new allele will take time, and perhaps that means at a minimum that the term "new" is somewhat subjective.Edited by NoNukes, : No reason given.

Faith is of course wrong, but it seems to me that it will be impossible for her to budge from her current position. She's saying exactly the same thing in her Great Debate. Not only does she deny that such any steps adding diversity are part of evolution. She denies that adding diversity is even an aspect of evolution or that Darwin ever considered it to be. This after all of the citing of biologists including Darwin who say otherwise. In my view the kinds of comments in the following excerpt border on being dishonest.

That's a good point. My question to you is why would you post here?I thought the purpose of the Great Debate was to provide a more comfortable forum for you because the group discussion is not working for you. If you are going to continue to post here, I think my comment to PaulK is still relevant. You are just as welcome to comment on my post as you are to post anything else here. Edited by NoNukes, : No reason given.Edited by NoNukes, : No reason given.

Faith's answer is probably along the lines of 'generating new genotypes is not evolution' or something similar to that.

Fair enough.

Faith, perhaps you should re-read my comment. I did not mention or say anything about generating a new phenotype. That also wasn't mentioned in the portion of the comment I responded to. Perhaps then we can discuss whether or not I have a clue. Edited by NoNukes, : No reason given.

Thank you. Now is the creation of new genotypes evolution? Mutations create new genotypes by definition. Does that, according to you, constitute evolution? Does my comment seem more reasonable in that light?From the Wikipedia article on evolution:Evolution - Wikipedia

quote:

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Precise mechanisms of reproductive heritability and the origin of new traits remained a mystery. Towards this end, Darwin developed his provisional theory of pangenesis.[54] In 1865, Gregor Mendel reported that traits were inherited in a predictable manner through the independent assortment and segregation of elements (later known as genes). Mendel's laws of inheritance eventually supplanted most of Darwin's pangenesis theory.[55] August Weismann made the important distinction between germ cells that give rise to gametes (such as sperm and egg cells) and the somatic cells of the body, demonstrating that heredity passes through the germ line only. Hugo de Vries connected Darwin's pangenesis theory to Weismann's germ/soma cell distinction and proposed that Darwin's pangenes were concentrated in the cell nucleus and when expressed they could move into the cytoplasm to change the cells structure. De Vries was also one of the researchers who made Mendel's work well-known, believing that Mendelian traits corresponded to the transfer of heritable variations along the germline.[56] To explain how new variants originate, de Vries developed a mutation theory that led to a temporary rift between those who accepted Darwinian evolution and biometricians who allied with de Vries.[41][57][58] In the 1930s, pioneers in the field of population genetics, such as Ronald Fisher, Sewall Wright and J. B. S. Haldane set the foundations of evolution onto a robust statistical philosophy.

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The false contradiction between Darwin's theory, genetic mutations, and Mendelian inheritance was thus reconciled.

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Edited by NoNukes, : No reason given.

Actually, a 'motley collection of phenotypes' sounds like a pretty good description for any large population of human beings. Subgroups of humans are not a collection of homogeneous clones. Getting us to look alike or to have similar traits as Faith seems to think is 'evolution' that would require a deliberate eugenics program. Which is what dog breeders actually do engage in.I'm curious to see how long the ever patient Genomicus can deal with her insistence on this erroneous path.

Of course we can define any subpopulation that we want.In the case of humans living among each other, I think this distinction would be a fairly artificial one I would think. Would not defining population to be the groups of people that have all the same characteristics amount to simply defining population in a way to make your statement true? I'm still chewing on this, but currently I am leaning away from accepting. You are not the first person from the UK that has reminded me of how little 'history' our country has. But here you understate things. Blacks and whites have been living together in at least some of what became the current country for well over twice that amount of time. As I mentioned in my post, my objection this does raise the issue of what is to be considered new. Also, for the most part, we are not talking about new alleles, we are instead talking about how long it has been since the population came together again. Presumably we all came from a single small group of humans originally. If "new" really means up to 4-500 years, that is probably something worth mentioning. I understand the basis of the mathematics, but I think deviations from that theoretical model are worth noting. It may be important to note that traits that are held by a small percentage of the population may take long time periods to become distributed through a large population. Even in a perfect situation, "new" is a relative term. I know. And surely we agree that her belief is wrong. You have made a number of arguments I personally find compelling, but I'm not sure insisting that non-new (by a nebulous definition) traits must be evenly distributed in a population is necessary to reach your conclusion. In fact I might well argue that the earth is covered with subgroups that are only cosmetically different from each other in the most minor ways. We are all inter fertile. Apparently not even 6000 years (yeah, I know that we mean hundreds of thousands of years) to accomplish what Faith claims happens.I note that Faith's belief involves not only some goofy mechanism that does not seem to produce what she claims (for example dogs are generally inter fertile) but also excludes any real role for natural selection via competition in addition to excluding mutation. Faith will only acknowledge evolution as a phenomenon that magically shows up when you subset a population and enforce the subset. There must be dozens of lines of inquiry that show that her explanation does not fit the facts and even more ways to show that she is not even attacking the real theory of evolution. Totally agree. My experience is that dogs, when left to their own devices are not all that selective. When I was a kid, we had a female mutt that most closely resembled some type of chow. The dog ran off for a couple of days and some time later delivered about six puppies that all looked exactly like the chocolate lab down the street, but each with the same bad temper as their mama chow. Of course our neighbor refused to pay us any puppy support even when we presented the blood test.[1]The point is that even with humans spaying/neutering, using buckets of cold water etc., to keep breeds intact, or just plain passing no mixing laws, humans and dogs don't end up speciating in the sense Faith claims. She's just plain wrong. It is difficult to express exactly how wrong without using adjectives/adverbs, but that would not really be productive.[1] Yeah, I know that letting your dogs loose like this is irresponsible. Please spay/neuter your pets if you don't want them to sire/birth offspring. There is no such thing as puppy support.Edited by NoNukes, : No reason given.Edited by NoNukes, : No reason given.