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Author Topic:   Molecular Population Genetics and Diversity through Mutation
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 409 of 455 (786522)
06-22-2016 4:44 PM
Reply to: Message 407 by PaulK
06-22-2016 3:14 PM


Re: A serious question for Faith
You can't just say that adding genetic diversity proves my argument wrong when the argument is specificallyl that genetic diversity MUST be reduced for a new species to emerge.
I've said rather more than that.
Well, you haven't, but I was actually addressing Dr. A's statements, not yoursk and thought you were too, since it was his argument I called obtuse. sorry I wasn't clear.
I have pointed out the fact that periods of decrease can be balanced by periods of increase, a consideration absent from your argument above.
That is exactly the same irrelevant argument I was talking about, nothing different, which is WHY it's absent from my statement above. I've addressed this version of it many times. Clearly you DON'T understand since you still think it stands. Periods of increase can happen of course, but during those periods you are not getting selection, isolation or indeed evolution, meaning change in a whole population, WHICH IS WHAT MY ARGUMENT IS ABOUT. All you are getting is scattered new phenotypes within the population. This is not what is needed to get a new species. You keep saying the new phenotypes themselves are needed. THEY ARE NOT. They add diversity but what is needed is selection and isolation to get a new species and until that happens all you are getting is willy-nilly increases here and there. And the increases are not needed anyway because there is plenty of genetic diversity to produce the changes I'm talking about, that are the actual evolution. Increasing diversity is not evolution. At best it's the material evolution works on. But it works on it by subtracting or reducing the less frequent phenotypes/alleles/genotypes so that the higher frequency phenotypes can emerge and come to dominate the new population. Your periods of increase are at best redundant. You really don't get it at all to continue to say they reverse the loss that is necessary to produce a species. AND AGAIN, if it did you'd never get established species, which presumably are the stuff evolution needs in order to keep evolving to other species.
I have pointed out that your arguments against mutations adding to diversity are simply assertions - and obviously false, at that. It's there in this thread.
It's a reasoned argument, not mere assertion.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
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Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 413 of 455 (786530)
06-22-2016 5:59 PM
Reply to: Message 411 by Dr Adequate
06-22-2016 5:54 PM


Re: Once again now, evolution of new phenotypes REQUIRES loss of genetic diversity
am aware of your dogma. You are still ignoring the fact that mutations increase genetic diversity. What you have shown is that if you remove mutations from the theory of evolution, you are left with an abortive theory that doesn't work. We knew that. But as you cannot effect a corresponding removal of mutations from reality, your botched and stunted theory of how evolution happens has no relevance to the world we actually live in.
You are certainly very good at saying absolutely nothing as if you were saying something. I don't deny that mutations increase genetic diversity, what I deny is that it changes my argument. One way you don't get it. Removing mutations leaves built-in genetic diversity so there is really no difference in how the scenario plays out with or without mutations. Another way you don't get it. And the rest is just you flying the Evo Flag and reciting the Evo Pledge.

This message is a reply to:
 Message 411 by Dr Adequate, posted 06-22-2016 5:54 PM Dr Adequate has replied

Replies to this message:
 Message 414 by Dr Adequate, posted 06-22-2016 6:25 PM Faith has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 415 of 455 (786540)
06-23-2016 12:00 AM
Reply to: Message 414 by Dr Adequate
06-22-2016 6:25 PM


Re: Once again now, evolution of new phenotypes REQUIRES loss of genetic diversity
Well, was this not your argument?
Faith, message#4 writes:
If evolution, meaning the production of a population-wide change in phenotypic presentation (black wildebeests to blue wildebeests, normal lizards to large-headed lizards, Darwin’s finches and so on, all changes normally called evolution) always requires a reduction in genetic diversity, that is obviously contrary to what evolution needs in order to do what the ToE says it does.
Now, if mutations increase genetic diversity, which they do, then this supplies "what evolution needs in order to do what the ToE says it does".
That would only be true, assuming the additions were viable, which they aren't but anyway, it would only be true IF the reduction in genetic diversity was not necessary to make new species. It's because of the necessity of this reduction through selection and isolation that any increases have to get reduced in turn IF species are to be formed. You don't have to have species, but isn't speciation considered to be the jumping-off point from micro to macroevolution? You don't have to have speciation but then you don't have the main part of evolution. Mutations won't do anything except produce a motley collection of phenotypes within a population. You can have all the genetic diversity you want as long as selection processes aren't operating, but then you don't have the evolution of new species. To get a species out of them requires reduction, throwing out some of them so that others get expressed. At the very least the constant addition of mutations would only slow down evolution of new species, making it start-stop-start-stop process, but eventually it has to stop if you do get a new species because added gene flow will mess it up. Again, this reduction happens whether the genetic diversity is built in or created by mutations.
Obviously. Darwin called his idea "the theory of descent with modification through variation and natural selection". The variation exists, and so the theory works.
Variation of phenotypes requires reduction of genetic variability. Darwin didn't realize that selection requires this reduction. It totally destroys his theory. Variation is not synonymous with mutations, it's what happens when some traits are selected over others.
Ignoring it won't make it go away.
Again, variation according to Darwin (and me) is the emergence of new phenotypes, it has nothing to do with adding genetic diversity.
Shouting and stamping your feet won't make it go away. Telling us in capital letters that that's not what your argument's about will not make it go away, but will tell everyone that your argument is predicated on willful blindness to incontrovertible facts. Then they will point at you and laugh.
I really truly can't believe you are this dense. I have to believe this is YOU being willfully ignorant.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 414 by Dr Adequate, posted 06-22-2016 6:25 PM Dr Adequate has replied

Replies to this message:
 Message 416 by Dr Adequate, posted 06-23-2016 2:27 AM Faith has replied
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Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 420 of 455 (786585)
06-23-2016 4:28 PM
Reply to: Message 418 by NosyNed
06-23-2016 10:49 AM


Re: Forgetful?
I guess you are as old as I am and so a bit forgetful.
That would only be true, assuming the additions were viable, which they aren't but anyway, it would only be true IF the reduction in genetic diversity was not necessary to make new species.
You have a number of "additions" remember? They are viable right?
Everyone has viable changes.
So that statement that they aren't is totally wrong.
Perhaps you could do me the favor of linking to the post where I agreed with this?
In any case, that was a parenthetical remark, meaning it doesn't really matter to the point I'm making if it's true or not. Even if viable, the point was that the addition of mutations or any kind of gene flow doesn't improve the situation caused by the fact that the reduction in genetic diversity is necessary to make new species. It can slow the processes of species-formation, it can blur the phenotypic character of a species etc., but adding genetic diversity doesn't do much or anything to change the trend to reduced genetic diversity NECESSARY TO THE FORMATION OF SPECIES.
Edited by Faith, : No reason given.

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Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 422 of 455 (786596)
06-23-2016 6:14 PM
Reply to: Message 416 by Dr Adequate
06-23-2016 2:27 AM


Re: Once again now, evolution of new phenotypes REQUIRES loss of genetic diversity
...which they aren't but anyway, it would only be true IF the reduction in genetic diversity was not necessary to make new species.
Uh, no.
In order for selection to take place, there needs to be a variety of genotypes to select from.
Of course.
Mutations supplies these.
Or they are built in from Creation.
The fact that selection is required to produce new species does not mean that mutation does not provide the variety that is selected from. Because why would it?
The fact that selection is required doesn't mean it couldn't be mutations that provide the variety, I just don't see that anybody has ever proved that to be the case. Hypothetically I grant that it COULD be true, I just don't believe it is, AND EVEN IF IT IS TRUE, it doesn't matter because the selective processes that bring about the new species will always reduce it and that will always be the overall trend of those processes and no amount of addition could do anything but muddy up the species.
Variation of phenotypes requires reduction of genetic variability.
That is a very odd collection of words.
It's nothing but the same argument I've been giving. To get new phenotypes, which is the kind of variation Darwin was talking about, not genetic diversity but phenotypic diversity, requires the loss of the genetic material that codes for other phenotypes than the selected ones. I CAN keep saying this even in the teeth of your refusal to understand it.
Darwin didn't realize that selection requires this reduction.
Darwin realized that selection was a selective process which selects for some variations and against others. This is why he called it selection. And ever since then, everyone who has undertaken even the most cursory study of evolution has understood it. I understand it. All the geneticists in the world understand it. Even you understand it.
What is not understood is that selecting for some variations and against others means the loss of the genotypes for the others. Nothing is added, only lost, in the selection of some variations over others.
What makes you unique is that you cannot also grasp what Darwin and I and all the geneticists everywhere can grasp: that if there is a constant supply of new variation, natural selection will never run out of variation to select from.
No, because natural selection is one of the subtractive processes that MUST reduce or eliminate a lot of that supply of variation in order to form a new species from some part of it. If you don't form species you may have lots of new variation, but then you aren't getting evolution. It's evolution I'm talking about, the formation of new species, which requires selection, which requires the loss of genetic material for unselected phenotypes.
Again, variation according to Darwin (and me) is the emergence of new phenotypes, it has nothing to do with adding genetic diversity.
If you can quote Darwin saying that or anything remotely like it, I shall eat my hat. But if, as I suspect, you are just making shit up, my hat will remain unscathed.
Darwin didn't know about genes or genetic diversity/variability, all he knew was the observed variation we all see: the different shell of the Galapagos tortoise, the different beaks of the finches, the pigeon variations he could produce himself by selecting for a particular trait. That these differences in phenotype require the loss of genetic material couldnt have been part of his theory. And this problem continues to plague the ToE today as you all actually seem to think that selection can just go on and on and on without cost, and once you see that there is some cost all you have to do is believe that mutations will save the day. Mostly though the cost isn't seen at all when evolutionary processes are described. What you really don't get is that it doesn't matter how much genetic diversity is in the main population of a species, when part of it is selected to bring out new traits toward the formation of a new variety or species, the great majority of the genetic diversity is left behind in the parent population, if it has enough numbers for that to be the case.
This is what was wrong with your "refutation" of my argument by the picture of all the dog breeds. Each of those breeds has only a small selected portion of the genetic diversity in the whole dog population, and it's the BREEDS that are "evolving," showing that evolution of new types requires that loss. It's in EACH breed that the argument is made. It's THERE that you see the formation of new phenotypes. It is THERE that evolution is going on. It really matters not one whit what the source of the genetic diversity is from which the breed is selected, to GET the breed means losing it or leaving it all behind. From what's left behind you may get lots of other breeds, and each breed demonstrates the same point: that selection requires reduction or loss. Since this is where evolution is actually going on it should be easy to see that eventually it could lead to complete genetic depletion and in any case CAN'T lead to the necessary genetic diversity for evolution to continue.. But then you want to add mutations and destroy those breeds? But then you don't have the platform for further evolution, you're back at Square One.
I've tried many times to create a graphic representation of this. I always find some way I'm misrepresenting what I want to represent and have to start over. And Paint is a klutzy medium which makes representing sufficient numbers to get across the point especially difficult.
I really truly can't believe you are this dense.
I am indeed not dense. Nor are all the geneticists in the world. Indeed, if you thought about it for a moment you might begin to suspect that if anyone is being dense, it's the woman who disagrees with all the geneticists about genetics while being repeatedly unable to define such fundamental terms as "mutation".
A mutation is a mistake in DNA replication. The vast majority of mutations are deleterious; there is a vast number of genetic diseases brought about by mutations. There is also a vast number of mutations that apparently do nothing to the phenotypic result of the change in the DNA and are called "neutral." Very very small numbers of mutations do anything at all useful to the organism. This information comes from the geneticists, not from me.
The problem is that geneticists, biologists, geologists etc. all subscribe to the ToE and always think according to its principles no matter how false and misleading they are. This gives you all a certain denseness when it comes to thinking outside the box.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 416 by Dr Adequate, posted 06-23-2016 2:27 AM Dr Adequate has replied

Replies to this message:
 Message 423 by Dr Adequate, posted 06-23-2016 6:42 PM Faith has replied
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Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


(1)
Message 424 of 455 (786602)
06-23-2016 7:30 PM


An attempt at a simple illustration
I haven't been able to find a way to represent the argument in some complexity, but it occurred to me maybe a very simple example might work better:
Say you select for the white flower, or bb. You grow hundreds of white flowers. There will be no pink flowers in your planting, no B's. no BB's or Bb's. You're aware that if you select a pink flower you may also get white flowers, but selecting the white flower gets you only white flowers. But let's assume you don't know anything about the genetics, you just know you selected the white flower and were able to grow only white flowers.
In a certain sense wouldn't you think you had evolved them? Isn't this what Darwin did with his pigeons, which led him to the principle of natural selection as the mechanism of evolution?
So now let's say you examine your white flowers and decide to see if there is another variation you can exploit, perhaps a tinge of color, and you find that some have a pale blue tinge near the stem so you select those; and among those you choose the larger flower as well. So you select for these small differences you find, and you discover you can indeed get a larger white flower with a tinge of blue near the stem. In fact you can keep selecting for the same traits, leaving out the weaker expressions of the selected trait and always choosing the stronger expressions. Assuming this is genetically possible you could eventually get a much larger flower than the originals, all with a striking blue near the stem.
So you've eliminated all the pink versions. Now you've eliminated all the pure white versions and all the smaller versions and got large white flowers with a blue center. Which you got by LOSING all the other versions you rejected. Your new flower has NO B alleles, no small size alleles, and no pure white alleles. You've probably got homozygosity for all those traits you selected. Perhaps you've even reached the point where cross-pollination has become genetically impossible between your new variety and those it evolved from.
What's happened? You've LOST genetic diversity by producing a new variety or species.
If cross-pollination is still possible you may be able to get it back. But then you will no longer have your large white flower with the blue center will you? All that change you worked to get is gone. All that evolution is gone. But you have all the genetic diversity you could want. And if mutations are also contributing to that diversity a lot more. But you don't have your new flower, your new variety.
Darwin's pigeons with the exaggerated traits he'd selected were still able to mate with the wild types and eventually the offspring reverted to that wild type. He lost his new pigeon types but got back his genetic diversity, though of course he didn't think in genetic terms. But if they had become genetically unable to mate with the wild types he'd have had a new species of pigeon, right? At the cost of all the traits in the wild type. It's an either/or: either you get the new variety with low genetic diversity or you lose the new variety in exchange for high genetic diversity. (It's possible after all your experimentation that you wouldn't get the original varieties back but some new combination of traits.)
Edited by Faith, : change stranger to stronger

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Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 427 of 455 (786605)
06-23-2016 8:12 PM
Reply to: Message 423 by Dr Adequate
06-23-2016 6:42 PM


Re: Once again now, evolution of new phenotypes REQUIRES loss of genetic diversity
AND EVEN IF IT IS TRUE, it doesn't matter because the selective processes that bring about the new species will always reduce it and that will always be the overall trend of those processes ...
Well, show your working.
I'll try to elaborate on the illustration I just gave later.
You admit now that there are two processes, one of which adds diversity, the other of which subtracts it.
I've never denied it.
If you maintain that there must be some tendency for the latter to win (contrary to reason and observation) then you are obliged to demonstrate and not merely assert this.
It's not a matter of "winning," it's that you can ONLY get a new breed or variety or species by subtracting, and if instead you add you will lose the breed or variety or species. That is indicated in my discussion of that illustration.
This is what was wrong with your "refutation" of my argument by the picture of all the dog breeds. Each of those breeds has only a small selected portion of the genetic diversity in the whole dog population, and it's the BREEDS that are "evolving," showing that evolution of new types requires that loss. It's in EACH breed that the argument is made. It's THERE that you see the formation of new phenotypes. It is THERE that evolution is going on. It really matters not one whit what the source of the genetic diversity is from which the breed is selected ...
Thank you. Very well then. If you can imagine evolution of all those breeds from a couple of wolves front-loaded with variation, then you can also imagine a subpopulation of dogs acquiring that much variation again through mutation, and so giving rise to as many new breeds. And the process need never stop.
Do you picture evolution as a process of making breeds/species and losing them then? Isn't it supposed to proceed by building upon what's already been established? If you add mutations you aren't building, you are losing the species you already had. If those mutations are SELECTED -- meaning you lose some to get yet a new set of phenotypes-- then you could get yet a new species. But it will be by losing the unselected traits as usual. You will have an overall loss of genetic diversity AGAIN, for this NEW species. You can get it back by mutations or gene flow if that is still possible, but then you'll just go through exactly the same sequence again if you are to arrive at yet another new species. This is a simplified description of what REALLY happens; it bears no resemblance to what the ToE is always presented as doing. "What's to stop microevolution from just continuing" is the usual query of the Evo, often repeated here at EvC. They aren't thinking of reduction of genetic diversity at all, of loss at all, they are imagining what they've always understood the ToE describes, the endless continuation of variation without a hitch or a glitch. No genetic cost, just onward and upward from species to species to species. Just as Darwin imagined.
'
But then you want to add mutations and destroy those breeds? But then you don't have the platform for further evolution, you're back at Square One.
Well, that's a funny way of putting it? Is the human species "destroyed" by having many races? Are chihuahuas "destroyed" by having all those different colors and patterns? Is Canis lupus "destroyed" by exhibiting the genotypes for all those breeds?
Mutations don't add "many races," they just change the existing race or breed or variety etc. The human species is not destroyed in any case, but a particular race of human beings would be lost if it completely mingled with another race or acquired enough mutations to change recognizably over time. That's what I mean. Chihuahuas don't stop being chihuahuas because of their many subtypes, but if they're all bred with cocker spaniels or allowed to mate with mongrels and reproductive isolation is not maintained then the chihuahua breed would no longer exist. Same if mutations kept changing them. (Canis lupus, by the way, doesn't "exhibit" the genotypes for all those breeds, those genotypes are the result of new gene frequencies brought about by selection. The breeds that emerge are not programmed into the Dog Kind somehow, they are the result of new genetic combinations. There must be hundreds of potential other kinds of dog breeds in the original Dog pool, that could have emerged instead of the ones we have, or if death had never entered Creation might still be able to have.)
(The odd thing is, of course, that if you think that genetic diversity "destroys" a species, then since you also think that God front-loaded the diversity, you must conclude that God created "destroyed" species to start with, and that we would undestroy them by extirpating the genetic diversity.)
It's ADDING genetic diversity when you already have a breed or variety or species that destroys that breed or variety or species. The original diversity is the necessary pool of variation from which new species are selected, but when the combination that makes a new species is selected from that pool, you have the species but have left the diversity behind --where it can still be the pool from which new breeds or varieties can be selected, (assuming there is still enough genetic diversity for that -- because of course after many subspecies have been formed eventually the original pool is also depleted.)
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 423 by Dr Adequate, posted 06-23-2016 6:42 PM Dr Adequate has replied

Replies to this message:
 Message 428 by Dr Adequate, posted 06-23-2016 9:30 PM Faith has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 431 of 455 (786610)
06-23-2016 10:18 PM
Reply to: Message 428 by Dr Adequate
06-23-2016 9:30 PM


Re: Once again now, evolution of new phenotypes REQUIRES loss of genetic diversity
It's not a matter of "winning," it's that you can ONLY get a new breed or variety or species by subtracting, and if instead you add you will lose the breed or variety or species.
And yet the human race have not been "lost" by the acquisition of different colors.
I do not understand how you are misconstruing what I wrote about losing the breed. The whole human race is not a breed or a variety, or even a race as the term is usually used. I've never said the whole Kind would be lost, just the breed or variety or species or race. And all I mean by lost is that its recognizable character, its specific traits, have been altered so that if enough change occurs it is eventually not the same breed. I'm not saying that the Kind of which it is a subvariety or subspecies has lost anything. All these subpopulations are characterized by a constellation of traits: a race is not merely a different color, it's a complete design unto itself, as is a breed or a variety etc etc etc Nothing is lost to humankind by acquiring different colors, meaning different races; and the design of a particular dog breed does not lose anything for the Dog Kind as a whole. I really can't figure out how you could read me as saying such a thing.
Do you picture evolution as a process of making breeds/species and losing them then? Isn't it supposed to proceed by building upon what's already been established? If you add mutations you aren't building, you are losing the species you already had.
No, you are increasing the variety of the species. Which is evolution.
Not if the mutations change the basic characteristics of the species so that it is no longer recognizable as that species. The many chihuahuas are still recognizable as chihuahuas by their size and basic body structure. And there is no reason to suppose that the differences are the product of mutations either.
If selection then picks out these new varieties and fixes them, replacing the old ones, this may go so far as to produce a completely different species. Which is evolution.
But when that happens the alleles for the traits for the varieties being replaced are getting reduced and can eventually be lost altogether. Yes you may get your new species, and yes that is evolution, but the only way you can get it is if the genetic underpinnings of the rejected traits are lost. Which I just explained in my last post. You can get a series of species by adding and subtracting but it's an either/or: you can have the species or you can have the genetic diversity. The species has to lose genetic diversity to become a species, and additional genetic diversity can only alter the species you have, which is what I mean by destroying it. Take your pick. Do you want evolution -- the formation of species which requires reduced genetic diversity -- or do you want high genetic diversity which changes the species? You can have high genetic diversity with scattered phenotypes in a population, which isn't a species, or you can have the formation of a new species through loss of genetic diversity. I believe all this is well enough illustrated in my example of the white flower.
Or if this only happens in an isolated population of the species, in which case you get a new species and keep the old one. Which is evolution.
Yes you can keep both, why not? But each requires the loss of genetic diversity, of the alleles for the traits it had to get rid of to develop those that characterize it. There's no way to get around that.
Again, your point seems to now be that yes, mutation happens, and yes, that means that evolution will never stop --- but that you consider this to be a bad thing. I can really make no more of your argument.
No, I say mutations themselves stop the processes of evolution that form new species, I certainly haven't said that mutations mean evolution will never stop, because evolution requires selection which always reduces genetic diversity. If you add diversity after you have a new species as a result of evolution/selection/reduction of genetic diversity, you simply lose your species. It's no longer the same species. You may get something else, even another species eventually, but you'll have lost the species originally selected. This isn't evolution, this is just adding and subtracting to no particular purpose. If you do get a species in the end it will be only because it's lost competing alleles for its collection of traits. And then you'll be alarmed again to realize that it HAS lost genetic diversity and want to get it back and around we go.
[qs]
Mutations don't add "many races," they just change the existing race or breed or variety etc.
That depends on whether they go on to be fixed in the species.
Too tired to continue. Have to come back to this.

This message is a reply to:
 Message 428 by Dr Adequate, posted 06-23-2016 9:30 PM Dr Adequate has replied

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Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 432 of 455 (786611)
06-23-2016 10:23 PM
Reply to: Message 429 by Dr Adequate
06-23-2016 9:44 PM


Re: Graphical Representation
I've many times tried to construct a similar graphic representation. It doesn't work. Yours is basically undecipherable. An interesting attempt though. But I'll have to come back to it.

This message is a reply to:
 Message 429 by Dr Adequate, posted 06-23-2016 9:44 PM Dr Adequate has replied

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Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 437 of 455 (786622)
06-24-2016 2:25 AM
Reply to: Message 436 by PaulK
06-24-2016 12:53 AM


Re: An attempt at a simple illustration
I have a question about your example.
According to you, if mutations were to produce new variations the child population would become indistinguishable from the parent Message 377.
I don't know where you are getting that from that message. After you have an established species mutations at loci specific to that species would turn it into something else, something not the species. It would destroy the species.
I, on the other hand, hold that would only be true if the mutations restored the missing traits, which is very unlikely.
I agree, and again I don't what I said that implied otherwise.
So, please explain this to me. It seems to me that the white flowers with a blue centre are distinct from the original pink population. And it seems to me that this would be true even if the blue centre was the result of a mutation. Why would you claim otherwise ?
Yes, it would be true even if it was the result of a mutation.
In fact, if the only difference between the pink and the white flowers is the colour is it not the case that any new variation other than restoration of the pink colour would leave the white flowers distinguishable from the pink ? Frilly petals, a change in leaf shape or even a blue variation would all be distinguishable.
Yes. You are supposing mutations for all those new traits, right? Are you talking about the appearance of one mutation in the whole population, a single flower with that trait?
Since this point covers an area of genuine disagreement, unlike your example, answering it may help move the argument on, after being stuck for years in the same place.
I brought up the example to demonstrate the necessity of losing alleles in order to get the new trait to become characteristic of the whole population. The argument is stuck on this point because it keeps being contested although it's my main point, and I'd rather continue to argue it than get stuck again in the question about whether it's mutation or created genetic variability that is the source of the selected changes.
You are of course assuming and asserting that mutations would produce a trait that would be just another selectable variation rather than something that would merely mar the species. I don't know how you could prove that, I think all you could do is assert it based on belief in the ToE.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 436 by PaulK, posted 06-24-2016 12:53 AM PaulK has replied

Replies to this message:
 Message 438 by Dr Adequate, posted 06-24-2016 3:17 AM Faith has replied
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Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 440 of 455 (786652)
06-24-2016 10:56 AM
Reply to: Message 438 by Dr Adequate
06-24-2016 3:17 AM


Re: An attempt at a simple illustration
I brought up the example to demonstrate the necessity of losing alleles in order to get the new trait to become characteristic of the whole population. The argument is stuck on this point because it keeps being contested ..
No. It does not "keep being contested". No-one contests that. No-one in the entire world has ever contested that. Everyone agrees that for one trait out of several to become fixed in the population, the other traits must be eliminated. ...
What makes you different from us is not that you (like us) understand what fixation is, but that you (unlike us) are ignoring all the other processes that take place.
Strictly speaking you are right that loss of genetic diversity isn't the thing being contested, and I misspoke, but it is still true that the typical way people speak of evolution implies that no such thing as loss of genetic diversity could be involved in it. When it's discussed in some detail you and others recognize the point, but it still doesn't affect how you think of evolution.
Which is of course because you think "all the other processes that take place" make up for it. And here you are wrong about me because I DON'T "ignore" those processes, I've knocked myself out trying to show how they do NOT make a difference in the general trend to loss of alleles. It's most of my argument.
CORRECTION:
ABE: I have to take back the above because of your post showing all the dog breeds that implied there is no loss of genetic diversity at all, missing the whole point I'd been laboriously making. That is a MAJOR misunderstanding, as good as getting absolutely nothing I'd ever said, and it keeps cropping up in this discussion, so I didn't misspeak, that basic point DOES keep getting contested.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 438 by Dr Adequate, posted 06-24-2016 3:17 AM Dr Adequate has replied

Replies to this message:
 Message 441 by PaulK, posted 06-24-2016 11:48 AM Faith has not replied
 Message 445 by Dr Adequate, posted 06-24-2016 5:24 PM Faith has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 442 of 455 (786672)
06-24-2016 12:53 PM
Reply to: Message 434 by herebedragons
06-23-2016 11:01 PM


Re: An attempt at a simple illustration
So you've eliminated all the pink versions. Now you've eliminated all the pure white versions and all the smaller versions and got large white flowers with a blue center. Which you got by LOSING all the other versions you rejected. Your new flower has NO B alleles, no small size alleles, and no pure white alleles. You've probably got homozygosity for all those traits you selected. Perhaps you've even reached the point where cross-pollination has become genetically impossible between your new variety and those it evolved from.
What's happened? You've LOST genetic diversity by producing a new variety or species.
Or... you now have a population of plants with pink flowers AND a population of plants with white flowers AND a population with large white flowers with a blue center. So you may have lost the pink allele in the white-flowered version, but that doesn't mean the pink allele is lost completely. And if they won't cross breed, you now have three separate species that originated from a common ancestor by descent with modification.
Groan.
I often fail to make ALL the necessary distinctions that belong to my argument in any given discussion, but I would think that by now it would be clear that I am ALWAYS talking about genetic diversity ONLY in relation to the particular breed or variety or subspecies I'm talking about. I do often remember to point out that plenty of genetic diversity remains in other populations of the same Species, I just don't always mention it. I'm NEVER saying ANY allele is lost "completely." The whole argument is about what happens in a particular population that is EVOLVING, not in the whole Species at large.
Faith writes:
Chihuahuas don't stop being chihuahuas because of their many subtypes, but if they're all bred with cocker spaniels or allowed to mate with mongrels and reproductive isolation is not maintained then the chihuahua breed would no longer exist. Same if mutations kept changing them.
Well, if ALL Chihuahuas bred with cocker spaniels, then yes, the Chihuahua breed would no longer exist. But what if only the Chihuahuas in Southern California were bred with cocker spaniels but the Chihuahuas in the rest of the world were not bred with cocker spaniels, the breed would not be lost.
Yes since this is about a whole breed that is scattered everywhere my language isn't clear enough to get the point across. I'm usually only talking about a NEW breed that just got formed, but chihuahuas can't be localized like that. The point I'm trying to make, however, is that in any given population any increase in genetic diversity will alter the breed. Dr. A's examples of variations on the breed which he attributes to mutations aren't what I'm talking about because those traits were selected as a breed themselves. And in order for that to happen, as always, competing traits have to be eliminated, so they are the usual result of reduced genetic diversity. But random mutations in an established breed will of course increase genetic diversity while altering the breed in UNdesired ways. That was the -- admittedly confusing -- point about unrestricted mating with mongrels, or putting cocker spaniels into the mix. {But again, of course a mutation COULD be selected and bred, but then again you'd be reducing the genetic diversity.)
But if they had become genetically unable to mate with the wild types he'd have had a new species of pigeon, right? At the cost of all the traits in the wild type. It's an either/or: either you get the new variety with low genetic diversity or you lose the new variety in exchange for high genetic diversity.
But there are still wild pigeons, right?
Of course. Groan.
And why do you consider losing the "wild" traits to be a "cost?"
It's the cost to the specific breed of forming that breed. It's the same loss of genetic diversity I've been talking about for seeming millennia, that occurs in an evolving line, toward the formation of a new species, that requires the loss of genetic diversity.
The point is that the traits in the new pigeon "species" were favored for some reason and so they were selected for. Yes, you have lost some traits in your new pigeon breed, but now you have a pigeon that is "better" than the wild breed.
No, that is not the point, not MY point anyway. MY point again for the zillionth time is that to get your new "better" breed or subspecies or variety REQUIRES losing the genetic stuff for the other traits. GETTING NEW SUBSPECIES REQUIRES THIS LOSS. YOU DON'T GET THEM OTHERWISE.
While it may be true that diversity has decreased from the wild type to the new breed, there is no reason that variation can't increase in the new breed due to new mutations.
Groan.
Have you even read any of the endless discussion about this very claim?
Of course if those mutations are undesirable, they will be unlikely to make it into the next generations. However, if they are neutral or of minimal effect they can continue to accumulate until the next selection event, where a desirable trait emerges (such as a blue center in a flower, a flatter, shorter snout in a bulldog, or a peculiar color in the pigeon feathers), ....
At which point the reduction in genetic diversity resumes as the new trait is incorporated into the breed. Always always always that has to happen when a phenotype is selected. It's my same point over and over and over again. Mutation or any other form of genetic increase is a liability to the breed unless a new trait is selected and the genetic diversity is again decreased by eliminating any traits competing with the new selected trait.
Honestly, this is beginning to sound like a slightly more sophisticated version of the "If humans evolved from monkeys then why are there still monkeys?" argument coupled with the no new genetic information argument.
Since you so egregiously misrepresent the argument it's no wonder if it sounds like something else. Perhaps you are just too busy to really follow the argument here? This post was like talking to someone who had never read anything I'd ever written on the subject.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 434 by herebedragons, posted 06-23-2016 11:01 PM herebedragons has replied

Replies to this message:
 Message 443 by PaulK, posted 06-24-2016 1:58 PM Faith has not replied
 Message 455 by herebedragons, posted 06-27-2016 12:26 AM Faith has not replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 444 of 455 (786688)
06-24-2016 3:49 PM


In case it seems like I'm abandoning the thread
For the next week I may not be able to participate much because I've got a lot of family things going on and will have only occasional access to someone's laptop. There's still a lot I want to respond to though.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 446 of 455 (786694)
06-24-2016 7:01 PM
Reply to: Message 445 by Dr Adequate
06-24-2016 5:24 PM


Re: An attempt at a simple illustration
... it is still true that the typical way people speak of evolution implies that no such thing as loss of genetic diversity could be involved in it.
No. You don't get to decide what people are implying.
And you don't get to tell me I'm "deciding" something when I'm giving a reasonable opinion. The fact is that the typical way evolution is described implies that variation is open-ended, without a hint of suspicion that loss of genetic diversity is inherent in evolutionary processes. Otherwise there wouldn't be this constant question one gets, "what's to stop microevolution from continuing."
And here I was thinking the tone of the thread had improved.
And if you ever notice us talking to creationists other than yourself, you will notice that we spend a lot of time shouting at them about natural selection, because most creationists take the tactic of ignoring that and focusing only on mutations. (It would be an interesting experiment to put you in a room with them and lock the door.)
In general people DO NOT think of natural selection as implying loss of genetic diversity. I don't think even you do except when you are in this sort of discussion on this thread.
Which is of course because you think "all the other processes that take place" make up for it. And here you are wrong about me because I DON'T "ignore" those processes, I've knocked myself out trying to show how they do NOT make a difference in the general trend to loss of alleles. It's most of my argument.
You probably shouldn't have knocked yourself out.
Well, it's going to continue for a while because it's still a hot topic.
ABE: I have to take back the above because of your post showing all the dog breeds that implied there is no loss of genetic diversity at all, missing the whole point I'd been laboriously making. That is a MAJOR misunderstanding, as good as getting absolutely nothing I'd ever said, and it keeps cropping up in this discussion, so I didn't misspeak, that basic point DOES keep getting contested.
No. Pointing out that there are lots of different kinds of dogs is not the same as contesting the existence of natural selection.
No, natural selection was never the topic, though for some reason you are now insisting on it as if it's synonymous with loss of genetic diversity, which among other problems ignores that natural selection is only one of the processes I point to as requiring loss of genetic diversity, another one I emphasize a lot more being geographic isolation and other forms of population splits.
What you were contesting was not natural selection but the loss of genetic diversity by implying that I'd overlooked how much genetic diversity there is in the Dog Kind as a whole, which is an astonishing misrepresentation of my argument after I've spent so many years trying to get it across and being told you get it you get it when you don't get it. Maybe you do now but I'm not holding my breath. And again, when people speak of natural selection they are not thinking of loss of genetic diversity or I wouldn't be having to work so hard to get it across. When the ToE is defined in the abstract no such concept as the loss of genetic diversity is even hinted at and in many discussions it seems to be implicitly denied. You just don't like being caught in an error so you have to get mean about it.
And yes, the production of a purebreed does involve homogenizing certain genes of that breed,
"Homogenizing" is an odd word in this context it seems to me, and I'm not exclusively focused on purebeeds. The trend is present in any breeding program or development of subspecies in the wild.
I never denied that, but on the other hand the careful preservation of mutations has added diversity to the whole species, to Canis lupus.
Which you can't prove.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 445 by Dr Adequate, posted 06-24-2016 5:24 PM Dr Adequate has replied

Replies to this message:
 Message 447 by Dr Adequate, posted 06-24-2016 9:24 PM Faith has not replied
 Message 448 by PaulK, posted 06-25-2016 1:13 AM Faith has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 450 of 455 (786706)
06-25-2016 11:37 AM
Reply to: Message 449 by caffeine
06-25-2016 9:47 AM


Re: Once again now, evolution of new phenotypes REQUIRES loss of genetic diversity
No I don't think it is what you all mean by evolution. The main thing is that you don't count in the loss of genetic diversity with each new species/subspecies. In reality you don't keep getting the mutations you claim occur anyway, but if you did there would be nothing that fits the ToE in a series of new species that all reduce the genetic diversity you suppose you get with the mutations you suppose you get.

This message is a reply to:
 Message 449 by caffeine, posted 06-25-2016 9:47 AM caffeine has not replied

Replies to this message:
 Message 453 by Dr Adequate, posted 06-25-2016 12:48 PM Faith has not replied
 Message 454 by NoNukes, posted 06-26-2016 2:52 PM Faith has not replied

  
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