Evolution Requires Reduction in Genetic Diversity

All you are doing is giving your own assertions. If you actually have evidence that I'm wrong provide it. Otherwise you are just being the pedantic nitpicker as I've often remarked, all hung up on definitions without bothering to understand what I'm trying to say.

I'm no geneticist either, but this topic has gone on way past standard ToE assumptions and I've been trying to give a creationist reinterpretation, so you can't just jump in with the usual stuff. This sounds like a lot of evolutionist theory but I don't even know if the diehard evolutionists here would accept your picture. I just have a bunch of questions myself: Where do you get the idea that a parent gives its offspring a genetic advantage? Why should that be so? And where would that offspring get the ability to strengthen the trait? And why or how should "a new genetic advantage" 'arise? Sounds like a lot of canned confusion to me. Meaning variation in traits or phenotypes, though you don't say anything to explain why there should be "greater variation" from the spreading out of the offspring. What would bring that about? So is this your explanation? The greater variation comes from variation in the environment? Why should there be variation in the environment, and how would that change the creature's variation? You mean it's just a new and different environment and somehow that forces the creature to change to accommodate to it?This sounds like sort of a confused halfbaked version of natural selection. And natural selection REDUCES genetic diversity. How they got here is not at all clear but OK let's say they did and this explains speciation. Nothing you've said implies a growth in genetic diversity.Edited by Faith, : No reason given.

It does not fail. Other than not mentioning where new genetic variations come from, you've pretty much nailed things.Faith is going to deny what you've said, but she has spent a decade or so doing that. Don't get discouraged if you cannot convince her.Edited by NoNukes, : No reason given.

"Where does the genetic advantage come from?"
There is a new "mutation" in each and every offspring. When two parents genes combine into a new creature, that creature is different than either parent.
Say the parents had strayed from the group and were now in an area that had more cliffs and mountainous terrain. This particular offspring just happens to have better foot pads than the parents, and can avoid dangers, find food, impress new mates better. This offspring transmits it's foot pads to more offspring, strengthening the trait. Only those who have the more appropriate foot pads continue the species. True, there might be some genetic inbreeding, while the group is isolated, but it need not continue to failure.As long as this group interacts with another before they get too divergent, the overall species will inherit the foot pads over time. Genetic diversity grows.The Earth is large enough to allow both isolation and reintegration with no problems.

Yup, but the differences do not require anything more than normal sexual recombination of the parents' alleles, they do not require mutations. Anyway, yes they're different. But there's nothing in either your scenario or mine to explain their having a genetic advantage over the parents. It "just happens" to have this very handy "mutation" that showed up just in time for the parents' move to mountain country? The ToE sounds positively Lamarckian at times. OK, one of the offspring might just naturally have slightly better feet for navigating mountain terrain, and if his siblings all fall off the cliffs and die then he'll pass those on, and yes the effect can indeed increase with each generation under such strict natural selection. But there's still way too much trust in something adaptive just happenng to show up by chance. Darwin got some extreme characteristics in his pigeons by breeding those with the best version of the characteristic he was looking for, but he chose that characteristic and their survival didn't depend on it. OK, that's more or less reasonable.But it doesn't say anything about genetic diversity. Sure but isolation is what produces new traits and ultimately species, is therefore microevolution, and as your own scenario implies, it comes with reduced genetic diversity. Reintegration, however, is an additive process, an increase in genetic diversity, it can interfere with adaptive traits, it allows genetic security but not evolution.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

What a dishonest way to debate. You could care less about evidence nor could you understand [ABE sorry, bad form. You don't lack the ability to understand; what you lack is the desire to understand. You would not put any real effort into reading and understanding a research article I post related to these issues] the research I would present. To demonstrate that my previous post is not just my assertion**, should I recommend a good book on population genetics?How about I give an example from my own research?The primary organism I work with is a pathogenic fungus, Rhizoctonia solani. R. solani is in the Basidiomycota, which includes the true mushrooms, the rusts and the smuts. These fungi do have a sexual stage but they spend most of their life as a dikaryon. The diploid stage of R. solani only lasts for a very short time, and as far as I know, has never been isolated in the field.Another of the characteristics of the Basidiomycota is that they have clamp connections. Below is a diagram of a clamp connection and how it regulates nucleus segregation during cell division (each nucleus shown is haploid and they divide by mitosis and are segregated into the growing cell so that each cell contains one of each nucleus). Interestingly, R. solani does not have clamp connections. It is the only member of the Basidiomycota without clamp connections (I think it is the whole genus but anyway...) Without clamp connections the regulation of nucleus segregation is poorly controlled and because of this, R. solani is multinucleate; that means it can have 4 to 12 nuclei per cell. These nuclei can have different alleles, and as many as 6 different alleles at a single marker gene have been found in a single isolate - 6 alleles for a single gene in one isolate!This does not happen in closely related basidiomycetes. They are (mostly) binucleate, that is they have 2 haploid nuclei per cell. So, they only have 2 alleles for any given gene.In addition, R. solani is further divided into subgroups based on the ability of the hyphae to fuse. These groups are called anastamosis groups (AG). These groups can be identified by genetic markers, or in other words, they each have unique genetic fingerprints. Furthermore, the AGs are further subdivided into interspecific groups (ISGs) which can also be identified by molecular markers. I am working on the diversity of the ISGs in one of the AGs in regard to host range, virulence and temperature response. The genetic groups have already been identified by a collaborator of ours and we want to see if there is anything significant (as it relates to plant pathology) in those groupings.So... how does your model make sense of this kind of genetic diversity???If R. solani diverged from the rest of the Basidiomycota and lost its clamp connection (which would be what is expected of a loss of function mutation) then the group gained genetic diversity over the course of time by adding multiple nuclei per cell (up to 6 alleles per isolate). If it went the other way and the diversity of the multinucleate state was lost to the other basidiomycetes, not only would that require an incredible amount of diversification it would require a gain of function mutation in the way of clamp connections.Your model is so overly simplistic that it is totally useless. It does not explain nor can it account for real-world observations regarding genetic diversity. The model I work with does make sense of it. It provides a framework with which I can further our knowledge of how plants and pathogens interact and how we can breed resistant crops and develop management strategies. All yours does is support your personal belief system.HBDEdited by herebedragons, : Clarification at **Edited by herebedragons, : bad form, sorry

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How does evolution arrive at what is called a new species? I know only one way: by forming daughter populations that bring out new traits or phenotypes because of their different allele frequencies, and a series of such population splits would get there sooner. And this process requires reduction in genetic diversity, variation or whatever the proper term is.

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Nothing has been said to indicate that there is any other way for speciation to occur.

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In fact it has been suggested that mutations are often required to reduce interfertility. Which seems more likely than your scenario.And, of course, we must not focus only on speciation events. We must recognise the increases in genetic diversity that occur at other times.

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Adding genetic diversity to a population by any means at all, migration or mutation or whatever, adds new phenotypes but doesn't do anything to make a new species out of them.

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Aside from being the likely cause of infertility between populations...But even if that were entirely true, what would be the relevance ?

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It doesn't matter if the diversity is added to a large population that subsequently splits, or if it is added at the end of a series of populations, to a subspecies or new species, the same process has to occur for the formation of further species: reproductive isolation of new traits breeding together, and that will reduce genetic diversity (the number of allelic possibilities)which makes further evolution impossible. So you get new diversity and the same thing has to happen and around we go. Evolution, meaning macroevolution, meaning evolution as understood by the Theory of Evolution, really is impossible.

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And this is obviously fallacious. If you bother to think it through it can easily be seen. For the argument to work it must be assumed that the reductions in genetic diversity are permanent. That no species can ever have as much genetic diversity as its parent species. But that is just an assumption, and an assumption that is very likely false.

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I do think that is obvious if you just think it through.

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Then I can only suggest that you do take the time to think it through, and pay attention to the responses you've gotten. Because if you did you'd see that it is NOT obviously true, and is in fact very likely false.

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Evolution in action is therefore ONLY microevolution, and it has a natural end point brought about by the loss of genetic diversity (or allelic possibilities) necessary to the creation of new phenotypes. If this leads to "speciation" it also leads to genetic depletion, which makes further evolution impossible.

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And that is still only your assumption. And given that the evidence is still against it, I see no reason to accept it.

But observably they do. I guess geneticists put "way too much trust" in observations, they should follow your lead and ignore the observable facts, maybe? Then they might agree with you. 'Course, in that case they would not, strictly speaking, be geneticists.

You were acting like you had solid evidence but weren't going to produce it.And of course I would expect your evidence to be on the level we've been discussing and that most online presentations of population genetics such as speciation seem to be discussing. Herd animals for instance, furry animals for instance, animals that get reproductively isolated behind mountain ranges for instance. Even human groups. And it sounded like you had lots of such examples.But now you give me a FUNGUS?If you don't have examples from the kinds of living things I've obviously been talking about, creatures with traits like eye color and tails and fur and etc., you don't have evidence against my argument. What a flimflam. Fungus???You are also using technical language which is your wont. What's wrong with English?And to give me a research journal article to read wouldn't be right either. You should put your evidence in your own words. Which apparently you did at least do with the fungus, except for the technical language.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.

Aha, so you admit that ToE genetics too is just a big fat fantasy.Edited by Faith, : No reason given.

I just read through your fungus presentation. You must be joking!If you really want me to think about it, take the time to explain every technical term in English, explain how any of it relates at all to anything we've been discussing, and explain what your model is which you say is so much better than mine. Which I'd never dream of applying to a fungus anyway.Good grief, HBD, you actually intended that as evidence against my argument?Edited by Faith, : No reason given.

Should I have said, "Now I see YOUR confusion?" ToE doesn't appear to be a fantasy to me.
You are basing your genetic advantage on a "response" to environment. But, it's a change from the parents, only, unless it proves to be an advantage. Every "child" is born with slight "mutations" from the parent, not all of which are advantages. Those mutations which are advantageous live on. Maybe the ones who ended up in the mountainous terrain were better suited to it BEFORE they migrated.Your own argument seems to be proof of evolution, since the same DNA is present throughout the biosphere. Your arguments against evolutionary progression are based on a limited number of alleles and genetic stagnation. The limited number though, is in the billions. If each alleles can be responsible for a mutation, then the possible combinations are in the hundreds of trillions. We might be headed for genetic stagnation ... but the Earth will cease to be habitable before we do.

Give me a break. You don't want to get it. I explained the terms that were unique to the organism I was talking about - like clamp connections. I read back through it and I don't see anything that is too highly technical; give an example. You can't understand this simple presentation yet you still know that population geneticists who work on these issues everyday are wrong and you have discovered the "true theory" of how organisms evolve. That is what is a joke. So, your model of speciation only works on ~1% of all the species on earth, but the rest of the 99% evolve by the regular old ToE? That is what is a flimflam. Fungi do have traits, they are sexually reproducing, R. solani does not reproduce asexually (many others do, but not R. solani). You rejected bacteria as an example because they don't reproduce sexually, you reject fungi because they don't have tails... That's actually the problem. The ToE works on all organisms not just the 1% that have fur and tails. Your theory needs to work accross the board, not just on your cherry-picked examples. To which your response is: Yes, shame on me for trying to define things properly. I know what you are saying, Faith. I know what your argument is and it is so overly simplistic, relies on a general misunderstanding of basic genetic principles, and fails to account for real world observations. The evidence against your overly simplistic nonsense is that the world is full of organisms with incredible amounts of genetic diversity. Diversity is not being depleted to some kind of end point where further diversification cannot occur. Rhizoctonia must be ancestral to other Basidiomycetes, and yet where is the reduced genetic diversity? It has gained diversity by having multi nuclei per cell.If your hypothesis can't be applied to anything but those organisms with fur and tails, it is utterly worthless to a biologist. If organisms continue to have significant amounts of genetic diversity despite speciation events, then we need to understand why. "Evolution requires a reduction in genetic diversity" doesn't do it.HBD

For all I know my model DOES apply to fungi, but they are too different from the examples I have in mind to find out. It is unfair of you to come up with an example you know I can't relate to, that has so little in common with the examples I've given, and where you require me to focus at the level of a cell when I've been focused on living things on a human scale. Give ME a break.ABE: Oh, and I could figure out most of the technical language but that is not the language we've been using here, it would require me to look up most of the words to be sure I'm using them correctlym, yet YOU are accusing ME of dishonest debate?Edited by Faith, : No reason given.

Yes.Go back and respond to Message 754 properly. If there is not an understanding of what is meant by genetic diversity, how can we decide that it has been reduced? My points were not just assertions but a description of some of the complexities and challenges related to defining and measuring genetic diversity. For example Go back and deal with Message 723 properly.I did not propose to "redefine" genetic diversity, but to use the term "genetic differences" temporarily for the purposes of discussing the chart I presented. Your Message 727 was a ridiculous way to respond as if I am the one who has no understanding of basic population genetics. No counter argument, just a 'no reason to take it seriously' attitude.And obviously I am not the only one who complains about the way you respond to arguments.So yes, I am saying that you are not debating in good faith.HBD