Evolution Requires Reduction in Genetic Diversity

But not when it is not selected right? Not every mutation is subjected to selection pressure, Faith. That's one generalization that causes you to err. Yes, but let's concentrate on mutations because they are important and because you offer only incorrect answers and reasoning when dealing with them. Mutations add diversity. They cannot detract diversity and they do not have to be selected in order to propagate through the populations. There they are a method for a population to increase diversity over time.Natural selection pressure operates on mutations that affect fitness. Other mutations can become fixed in a population through drift which means that they increase diversity when they occur. This is the principle that you simply deny. That's a complete nonsense response. Any time I describe variations that are generated by mutation, I am by necessity talking about variation that represents a new genotype. New alleles produced by mutation cannot simply be new phenotypes. Perhaps you would best be served by getting another headache instead of typing in unresponsive stuff.

If it is not selected, or high frequency in a subpopulation, then it has no part in these processes of microevolution that bring about new traits that come to characterize new populations and ultimately speciation. And if it does become high frequency and a major player in the formation of a subspecies or even speciation, then again we see the reduction in genetic diversity I keep talking about that brings evolution to an end. It always comes back to this same point. You cannot get past the fact of reduced genetic diversity. So you have a new trait, if the population can't continue to evolve that's all you have, a new trait with no possibility of further evolution.You are of course still missing the point.And mutation doesn't happen as you claim anyway. I allow it as a hypothetical because it really doesn't change my argument. But in reality mutation has nothing to do with the formation of new subspecies and you have no evidence that it does in the situations we are discussing, or even that mutations are ever viable alleles, it is purely an assumption that the ToE requires, but in reality all the phenotypic change we see is the product of recombinations of new frequencies of pre-existing alleles.Edited by Faith, : No reason given.

1. IF inbreeding were the regular thing happening in populations I could even agree with you.
   But inbreeding is not the regular thing happening in populations.
2. IF evolution were only about recombination of existing alleles in a splitting population, I could agree with you. But evolution is ALSO about gene drift, genetic innovation by mutation and selection.

Yeah let's do as if gene flow is not there. Hence:

3. IF there was no gene flow, I could agree with you. But gene flow IS happening. All the time.

After which i provided several examples of sexually reproducing creatures.Yeah, let's do as if there were no mutations that have experimentally and observationally shown to lead to genetic innovation. Hence:

4. IF there was no genetic innovation due to mutations and selection, I could agree with you. But mutations ARE happening. All the time. And selection is selecting.

So yeah let's ignore all those things and just feign they do not happen.
Let's disrobe evolution of all its principal features and then start to beat up the left-overs.
The great disappearance and cover-up trick.BTW, when do I get the answers on my questions, do you think?
See my posts: Message 578. Mind me referring back to previous ones in the post as well. Please incorporate them in your answers. As well as post Message 583. And Message 584. And Message 587. Or what about Message 622?Edited by Denisova, : No reason given.

Fine with me. If both populations are very large THEN and only then could the allele frequency be the same. I don't know how much smaller the daughter population has to be to start seeing a difference made by different allele frequencies but possibly not a lot smaller. Of course, yes, the smaller the bigger the difference. This is obvious. As I've said, I think counting the loci for the characteristic traits should do it, but this is of course open to discussion. How on earth is discussion possible with someone as intent as you are on nitpickingly precise pedantries that miss the spirit of what I'm saying? I USE THE TERM "INBREEDING" TO COUNTER THE OTHER NITPICKING PEDANTRY THAT INSISTS THERE IS GENE FLOW WITH THE PARENT POPULATION IF I DON'T SPECIFICALLY SAY THERE ISN'T. Good grief. Sigh. Fine. I will throw out another perfectly good word because of your inability to get the context. Right, and I'll say that and you'll say then there is gene flow and I'll want to punch you in the nose and not be able to.ABE: NEVER MIND. I see that I should have anticipated this. I really thought the word had the meaning I ascribed to it but apparently you are right and that specific meaning of mating close relatives IS the meaning and I'll only confuse everybody if I use it as I have been. Interesting Percy got what I meant though. /ABE Great.But now I have to stop for a while.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

I may or may not get back to your posts with the current activity I'm dealing with.If you want me to answer your questions, please write out ONE question so I'll know what you are talking about.

Wrong. Mutation plays the part of adding diversity to a population. At some later time, after diversity has accumulated, one or more of the traits in the population may become the basis of selection. There is no requirement that the trait that is the basis of selection be the most recently added trait. No, you've missed the point. Apparently deliberately it seems. I've provided several examples and you haven't addressed any of them. In this case, you are so busy making your own point that you haven't addressed the the issue. Actually, you don't do that. Instead you pretend to allow mutations while denying their consequences. Go back and re-visit the lunar isolation scenario, but allow mutations and selection to reduce diversity in the lunar population as you insist on. Are you still denying that upon re-integration with the main Russian population that humanity as a whole is more diverse? If so, then you are not allowing mutations.And you've been given real world examples of mutations that do result in new traits, so your denials are against the weight of the evidence anyway. And of course if your answer is just to deny that mutations work as the TOE claims, then your discussion is of no interest to anyone. Edited by NoNukes, : No reason given.Edited by NoNukes, : No reason given.

Well, I have had to take back my use of the term "inbreeding" as I see it was causing confusion. In this case I don't know how you are using the term or what it has to do with what I'd said. Decreasing genetic diversity is the result of the microevolution of new phenotypes in smaller populations or by selection, which amounts functionally to the same thing. If you mean the mating of close relatives, of course not. But again I don't see the relevance of any definition of inbreeding here. There are really two directions here: Drift and selection are functionally the same thing as recombination of alleles in a subpopulation. They all completely or partially isolate new frequencies of alleles into their own breeding population where the new traits based on the new allele frequencies emerge over some generations, if isolation persists, to produce a new subspecies.Mutation, however, just acts as another allele in the pool. If it's high frequency or strongly selected it will contribute its trait to the phenotype, but other alleles for that same trait will be low frequency or drop out completely and that's the reduction of genetic diversity that ALWAYS occurs when a new subspecies is developed. \But it doesn't change the fact of reduced genetic diversity when new traits are coming to characterize a daughter population, it merely makes the route to the end result more circuitous and hard to follow, so changes nothing essential. It's dispensable. The mutations in those instances almost act like they were produced on demand rather than randomly. Mutations don't just happen to show up to save the day, in fact a helpful mutation may never show up, so those examples can't possibly be taken seriously in this discussion. BUT EVEN IF THEY WERE, mutations all share the same fate I keep describing of either becoming part of a subspecies which inevitably reaches a dead end beyond which no further (micro)evolution can occur, or not being selected and being irrelevant in this process anyway. Genetic innovation can't stop the processes of microevolution that lead through degrees of reduced genetic diversity to ultimate inability to further evolve. There is no evidence that they can contribute a useful allele at all ever except those odd examples you mention, but even if they did they would only supply a variation on a trait that would end up in a new "species" that has no ability to evolve further, or not even be selected at all. See above.And again, If you want me to answer your questions, please write out ONE question so I'll know what you are talking about. Edited by Faith, : Add last sentence.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

Is this not a discussion of population genetics? It is not a matter of being nitpicky, it is a matter of understanding. If basic terminology and concepts are not clear, how are we going to be able to look at research on these subjects? For example, when I see you have written something like this: it just gives me this nagging feeling that you really don't understand the concepts you are pontificating about. In this case, inbreeding and gene flow are two separate issues; because a population is not inbreeding does not give me a clue about what kind of gene flow is going on. So I think, "Wait, she is confused about something here" and I try to clear up the confusion. Thank You. And yes, you should have anticipated this. Population genetics is my sub-specialty after all. What you are describing is a daughter population that is breeding in isolation from the parent population. It is that simple. Inbreeding may or may not be a part of the situation, but unless an increase in the proportion of homozygotes is important to your case, maybe there is no need to bring it up. However, inbreeding can affect genetic drift and so alleles can become lost or fixed more readily. Great. I think more discussion about what is meant by "genetic diversity" is seriously needed.I would like to know what you would consider to be a gain in genetic diversity. Would changing the proportion of heterozygotes be changing the genetic diversity?How would you measure genetic diversity? What criteria would you use to compare genetic diversity in two populations?What would you expect to see in a population that has lost genetic diversity? (should be something measurable)HBD

I am just now finding out that you have a background in population genetics. You've seemed to present yourself as just learning about all this stuff for the sake of the debate so I don't take you seriously and think your insistence on terminology is just the pedantry of a novice. I haven't tried to learn a great deal of population genetics, for one thing there's too much math, and have contented myself with learning enough to support the framework of my argument, which I discovered early on it definitely does; apparently getting some terminology wrong in the process. But if you are knowledgeable about all this then maybe I can pick your brain for my purposes. However, I've already found out that you are stubbornly committed to evolution, so we'll see. Which would be fine except you may guess wrong about the nature of the confusion. I had just explained that I keep using the term "inbreeding" to refer to breeding within the daughter population to try to keep it clear that this population is reproductively isolated. If I just said "breeding" I'd be afraid it wouldn't be clear that there was no gene flow between this population and other populations. But now seeing that the term causes confusion I'll look for other ways of saying that. Which had just begun to dawn on me over the last few posts. I knew you worked with plants and that's about it. Yes it is but I keep having the experience that nobody gets even the simplest things I say. But now I can perhaps make use of your expertise hoping the usual frustration and confusion might begin to get straightened out. I never had a reason to make the breeding of close relatives a part of the situation at all, using the term only as described above, but nevertheless, yes, the proportion of homozygotes does become increasingly important as genetic diversity keeps getting reduced through a series of subpopulations forming from earlier subpopulations. Inbreeding as properly defined would apply at those later stages, but nevertheless I would still have no cause to use the term that I can think of so I vote to jettison it from the discussion completely. But genetic drift can be described well enough without reference to inbreeding.For the sake of clarifying how I use some concepts in an unorthodox way: Genetic drift is to me just one of the forms of microevolution that leads to reduced genetic diversity, along with selection both adaptive and random, and population splits of the sort I keep focusing on which I think of as a form of random selection. These together I think of as the "subtractive" processes of evolution that can lead to speciation. I separate these from the "additive" processes that are also called "evolutionary processes," such as "migration" in the sense you use it, and mutation and anything that brings about or maintains gene flow between populations. These are all usually lumped together in a list of "evolutionary processes" so my putting them in different categories is my own thing. And if what I'm trying to do is clear here, then please correct my terminology as needed; and if it's not clear then let's try to make it clear. Yes. High heterozygosity is pretty much synonymous with high genetic diversity as I think of it. I would want to compare parent and daughter populations, especially through a series developing one from another, and I'd be looking mostly for a decrease in the number of alleles for the particular genes that underlie the most characteristic traits. Once fixed loci develop for those traits, which is what I'm expecting to see increasing from population to population the task should be easier. The more fixed loci the lower the genetic diversity as I've been thinking of it. A decrease in number of alleles per locus for the characteristic traits, leading to an increase in fixed loci for those characteristic traits from daughter population to granddaughter population to great-granddaughter population etc.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.

PARDON???????No evidence?See my previous post which points back to unanswered and dodged OTHER post by me - MANY.Tell me, Faith, HOW do you manage to LIE all the time?

Evading all the point i made, I do not see any reason to address this.
Please answer my MANY questions.

Not quite.If the mutation is for a new completely novel trait, then nothing at all is lost at selection. We just get a new winged variety vs non winged varieties. At that point we can still have interbreeding between the two varieties which reinforces that no diversity is lost. And there may later be new alleles for the new trait.If the mutation is simply for another allele of an existing trait, then the other alleles could be lost, yes if there is selection. However given that there may be multiple non-selected alleles for other genes from mutation before the final one that is selected, the result is still not of necessity a net loss of diversity.It is true that the new species must have wings, but it might have both curled and uncurled ears if that was one of the non selected mutations. Or it might have stripes or be without stripes if that were yet another mutation propagating via drift (non selected). Or it might have pug noses vs straight, nappy hair vs straight, or whatever non selected traits appear.If the environment changes, then perhaps one of the non selected traits does become beneficial or detrimental. But by that time there may be many other mutations that are either neutral or of minor advantage such that they are not selected. So again a loss but not a net loss.The point is not that no diversity is lost during evolution, even though I can postulate such scenarios, the point is instead that no net loss of diversity occurs of necessity. Sometimes yes, and sometimes no.

My questions date back WEEKS.
You seem to have enough time to write a lot of posts.
Moreover, 2 weeks ago you wrote the same reason not answering.
not very convincing.

Hi Faith,Maybe this has already been cleared up, but let me try again.You don't need the term migration. Your scenario only requires isolation. Physical migration is just one way to cause isolation, but it doesn't matter how isolation was caused. Physical migration is just the simplest and easiest to understand cause of isolation.So when you want to refer to the actual movement of a subpopulation from the location of the main population to another location I suggest you use the term physical migration, but realize that it is not a synonym for isolation, which is the situation you really need.Edited by Admin, : Improve clarity.

I don't think Wikipedia is saying this. Here's the Wikipedia quote you're referring to that you claim describes a way speciation can occur without mutation, copied from your Message 679: This opening summary doesn't mention mutation, but the mention of evolution implies that of course mutation plays a role, and if you read further through the article you'll find this: So Wikipedia is not claiming that the founder effect can lead to speciation without mutation.The unanswered question is how a subpopulation armed only with alleles already in the main population could arrive at genetically incompatible allele combinations. Unique allele combinations? Sure! Incompatible ones? How?