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Junior Member (Idle past 3469 days) Posts: 13 From: mississippi Joined: |
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Author | Topic: If evolution is true, where did flying creatures come from? | |||||||||||||||||||||||||||||||
Faith  Suspended Member (Idle past 1444 days) Posts: 35298 From: Nevada, USA Joined: |
Let's assume the ancestral species lived in lush, wet environments but that the habitat of one of its subpopulations is living in an region where the climate becomes very dry and arid. Basically these animals have 3 "options": 1. adaptation to the new conditions, or: 2. migrate to lush regions so they can resume their old lifestyle, or: 3. get extinct. Actually, all happen and are observed in an abundance on field observations and even experiments. Now let's assume that migration is not possible (predators there, overcrowding, some geographic barrier etc.) and the species manages to adapt. So, first the genetic variance in the species' TOTAL genome (including the ones still living in the original lush habitat AND the ones living in the area that is getting more arid) INCREASES, WHAT? Both populations have an increase in genetic variance /diversity? And what brings this about? It would be amazing enough of one did but you are blandly saying bothdo? At the same time?
mostly by genetic innovation in the "arid" subpopulation What is genetic innovation and why would this occur at this point?
- the ones living in the original, lush area don't need to change (other than through genetic drift) because they don't experience new environmental change. Genetic drift does not increase genetic diversity. It’s like any subpopulation with random new gene frequencies even though this occurs within the larger population: If it acquires new traits it loses genetic diversity, which is the ONLY way new traits can be acquired. And you haven’t said one thing to this point about how such a genetic increase is possible, what could possibly bring it about, and it looks like you have no intention of explaining that:
AFTER this increase, the genomes may split up. But each subpopulation picks up only a part of this INCREASED genetic variance. I HARDLY doubt ANY of the two subpopulations having a genome with less genetic variance than the original ancestral genome though. Not in the subpopulation living in the original, lush environment because there was no much need to change. But NEITHER in the "arid" subpopulation because in those animals the traits that relate to living in lush environment will be discarded (genes disabled by mutations or just by plain gene deletions) and new genes will be formed (by gene duplications or altering old ones). A little calculation already proves this. Let's depict the original. ancestral genome in this, simplified way, where each Xi represents a single, distinct gene: Ga = X1-X2-X3-X4-X5-X6-X7-X8-X9-X10-X11-X12-X13-X14-X15-X16 After one subpopulation experiencing arid conditions:G1 = X1-X2-X3-X4-X5-X6-X7-X8-X9-X10-X11-X17-X13-X14-X15-X16 (the subpopulation still living in unchanged, lush conditions, hence, genome only changed a little bit due to genetic drift, represented by the gene X17, retrieved from the original gene X12) PLUS: G2 = X1-X2-X3-X4-X5-X17-X7-Z1-X9-Z2-X11-X12-Z3-X14-X15-X16-Z4 (the subpopulation experiencing an more arid environment, adaptation through the new genes Z1, Z2 en Z3, replacing old genes X8, X10 and X13, which are disabled, mutation of old gene X6 into X17 and the new gene Z4 - added without replacement of former genes). So, as a matter of fact, I should redrawn the picture for G2 as follows: G2 = X1-X2-X3-X4-X5-X17-X7-(X8)-Z1-X9-Z2-(X10)-X11-X12-Z3-(X13)-X14-X15-X16-Z4 where (X8), (X10) and (X13) represent the disables genes whose sequences still are there but "degraded" to junk DNA (to pseudogenes). IN OTHER WORDS, in the sub-genomes there is ANY reduction in genetic variance. I assume you meant to say there ISN’T any. Well, I went through all of this and have no idea what you’re talking about. I expected some serious explanations at least, but all you did was say oh there was an increase in genetic diversity and both subpopulations had this increase. You seem to be implying that the environment brought it about but offer no explanation how that could be. As for the math, it's meaningless to me. You have to use English. This example of a supposed increase in genetic diversity is so devoid of reason or meaning I have to ask, are you joking?
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Faith  Suspended Member (Idle past 1444 days) Posts: 35298 From: Nevada, USA Joined: |
It's a position I take for the sake of argument since the source of genetic diversity isn't important for most of this discussion ...
Well it is kind of important since it wrecks your entire argument. If there's a constant source of genetic diversity, then there is a constant supply of raw material for selection, evolution need never stop, Once again, Dr. A, you prove you do not have Clue One about the argument I'm making. Evolution doesn't come to an end for lack of genetic material, it comes to an end because the processes that bring it about require the reduction of genetic material.
and even if your fantasies about species formation were perfectly accurate, new species would not in the long run lose diversity. Or to put it another way, if there's a constant source of genetic diversity then we'd be living in the real world and would observe the things that we actually do observe. You can have all the genetic diversity you want and still wherever evolution is actively occurring, wherever new traits are developing in new subpopulations, you are getting reduced genetic diversity as a necessary consequence and for that evolving line you are running out of the fuel for evolution. You can have lots of fuel in the mother population but if it's not forming new subspecies then you don't have evolution. I know it's hard for you to consider you could be getting this wrong, but you are. Please rethink it. Edited by Faith, : No reason given. Edited by Faith, : No reason given.
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Faith  Suspended Member (Idle past 1444 days) Posts: 35298 From: Nevada, USA Joined: |
Your statement is wrong on several fronts. Once a subspecies forms from a mother population, added mutations can increase diversity in the new subspecies. You've tried to argue that this destroys the subspecies but you are wrong. Sub species can, and in the wild do have diverse members. This can of course be true, but to the degree they retain genetic diversity it's to that degree that they are not evolving in the sense I'm talking about, toward speciation, because despite your inability to get the point that DOES require the reduction of genetic diversity.
In this way, species differ completely from breeds which are artificially wrong on several fronts. Eh?
Eventually the new diversity might well replace the single gene on which the original speciation event is based. What "single gene?" What "new diversity?" I'm sorry, not getting what you mean.
The second front on which you are wrong is that evolution is the change in genetic makeup in a population over time. Evolution occurs even when speciation is not happening. Yes, and if new traits are forming slowly within a population over time that's evolution too, and that too requires the loss of genetic diversity. It's just easier to grasp what's happening where subspecies are actively being formed, to see how the reduction of genetic diversity is required to bring about new traits.
Your case is pure nonsense, and everybody here including the posters who arrived five minutes ago can see the problems with it at a glance. I'm not at all surprised if people can't get it and think they see problems in it, because everybody has been indoctrinated in the completely opposite point of view.
FWIW you've already admitted to enough so that your statements are a concession of the entire argument. At a minimum, you've admitted that you don't have proof, but belief. And secondly, you've admitted enough about mutations to allow evolution as described by the theory of evolution to work. I'm curious to see how you attempt to deny your admissions so that you can pretend to have won this argument six months from now. None of the admissions affects the basic form of the argument.
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Faith  Suspended Member (Idle past 1444 days) Posts: 35298 From: Nevada, USA Joined: |
You are still wrong for just the reason I explained: if you have a constant supply of fuel, you do not run out of fuel. Well, fuel is not a very apt analogy for what is really going on. This is a dynamic thing that REQUIRES the loss of fuel to occur at all. Adding fuel will just keep it from occurring. Oh well. Maybe it will come to you in a dream. Edited by Faith, : No reason given.
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Faith  Suspended Member (Idle past 1444 days) Posts: 35298 From: Nevada, USA Joined: |
I overused my eyes yesterday, have a horrible eyestrain headache and have to be off the internet at least until tomorrow, hope not longer. I'm curious to find out if Denisova ever said anything coherent, and I'll try to deal with the rest of RAZD's post.
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