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Member (Idle past 722 days) Posts: 20714 From: the other end of the sidewalk Joined: |
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Author | Topic: Peter & Rosemary Grant, Darwin's Finches and Evolution | |||||||||||||||||||||||||||||||||||||||
Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
But the vast majority of those mutations are either deleterious or "neutral" and proving even a single beneficial one that could be passed on is rare and often not even a certain thing.
As do I, which is what this is all about.
No, you observe new phenotypes emerging but the idea that this is due to mutations is purely theory. In the case of the pocket mice you have some basis for believing it though I think it's pretty iffy myself, and in the majority of the cases it's all theory that is in fact highly unlikely, even impossible since mutations are random and mostly of no benefit whatever. The new phenotypes emerge due to the shuffling of the allele frequencies brought about by the reproductive isolation alone working on the BUILT-IN alleles shared within the new populations. BUT EVEN IF MUTATIONS WERE THE SOURCE OF THE NEW PHENOTYPES, you still have to have a reduction, sometimes elimination, of the competing alleles for the traits that emerge in the new population.
There isn't such a thing. You would run out of genetic potentials for change in phenotypes long long long before you get to any kind of change that isn't simply a variation in a built-in trait that belongs to the Kind.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
It would if mutation had anything to do with creating viable alleles but even you all acknowledge that the vast majority are either neutral or deleterious.
I think you extrapolate this from the observed fact of new mutations occurring from generation to generation, plus the theory that requires you to believe that they are the source of functioning alleles, although this is belied by their generally nonbeneficial nature. Unfortunately the result of the accumulation of these different mutations in any population is ultimately most likely genetic disease, not the emergence of new healthy phenotypes. Again, the observed divergence between populations needs no other source than the change in gene/allele frequencies that is the natural result of the splitting of the populations itself. The best you can say for mutations is that the built in alleles wre originally the result of mutations, because the new mutations would not be of any use in bringing about this divergence, since they would have to be passed on in the population, which is not too likelyl to happen to any given mutations in individuals. Edited by Faith, : No reason given. Edited by Faith, : No reason given. Edited by Faith, : No reason given.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
I am not going to read a whole thread to find a few posts of yours. This is a typical ploy of yours to confuse and obfuscate, which is a violation of decent debate practices. It is your job to produce the evidence you are claiming, a link to the relevant posts or just a restatement of the evidence.
Edited by Faith, : No reason given.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
I don't recall reading anything you wrote about any of that except the American Curl, which is a completely different breeding process than the normal one, with different objectives. It doesn't produce just one single breed but a large variety of cats with curled ears. When enough numbers of cats with curled ears exist so that the trait is assured continuance, then the usual breeding process I've been talking about takes over, the process which requires the reduction of genetic diversity in the effort to develop a distinctive breed of cat with curled ears.
Remember, I'm talking about what happens in the development of a race or breed or subspecies, not a single trait. ABE: HOWEVER, I would also point out that to get that curled ear in any population requires the suppression, reduction or complete elimination of the alleles for straight or any other kind of ear. So the same principle operates even here. Edited by Faith, : No reason given. Edited by Faith, : No reason given.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
? Um, there is a large variety of human beings with brown eyes. They don't constitute a race which of course means this has nothing to do with the processes I am talking about. Edited by Faith, : No reason given.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
Black cats, calico cats, longhair cats, shorthair cats, all having the curled ear, do not constitute a breed. In a dog or cat show the whole animal is judged as to whether it is a good representative of its breed, not one single feature.
But you are talking about the diversity of the "breed" (which is not a breed precisely BECAUSE of its diversity) -- that is, the phenotypic diversity of the species, the cats themselves, which is NOT what I've been talking about. The diversity of the phenotypes may increase for many reasons in the wild too but this has nothing to do with the creation of a race or breed. The ONLY diversity I've been talking about is GENETIC diversity, and this gets reduced for the characteristic traits at least when an actual race or breed is developed, which ideally does NOT have phenotypic diversity but quite the opposite, a recognizable phenotypic portrait which is what MAKES it a breed. Or in the wild a race, a subspecies.
I've produced a description of the normal way breeds have normally been developed, from a limited gene pool of selected characteristics, and by ELIMINATING those traits or characteristics that interfere with the breed. When you eliminate traits you eliminate the alleles for those traits. This should be recognizable, I shouldn't have to produce a specific example, but I probably could if I read up on the various breeds of cattle or even the different subspecies of wildebeests. As I recall it took about a hundred years to develop a "truebred" Hereford. That's a cow with NO phenotypic diversity in its identifying characteristics, all Herefords, all genetically having the same identifying characteristics WITHOUT BEING CLONES. How did they do it? By eliminating cattle that had the "wrong" traits from the breeding pool. Of course this is eliminating the genes/alleles for those traits. What you have produced on the other hand is an example of something completely different, not the production of a breed but really the opposite that came about through the pursuit of the preservation of a single trait. For that single trait there had to be the same kind of elimination of competing traits, but a single trait does not constitute a breed. [qs] Remember, I'm talking about what happens in the development of a race or breed or subspecies, not a single trait.
Again you are talking about phenotypic diversity which is not what I am talking about. I have not read anything you wrote about other "breeds" than the American Curl. If the other "breeds" follow the same pattern then they are all NOT what has normally been regarded as a breed, as a single trait is not sufficient to define a breed, the way brown eyes are not sufficient to define a human race. If you don't understand my words you will continue to be in thrall to the wrong facts.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
This is pure nonsense that proves only that you don't have a clue about what I'm talking about. I said it is not easy to grasp, it requires THOUGHT, thought over TIME, a few hours over a few pots of coffee at least. All you are doing here is semantic juggling. You all DO call a new race of animals in the wild a "species" but that's really a tendentious term when you are merely assuming something based on your theory. The terms were not all that clear in Darwin's day. Darwin called his finches "species" but they were merely races or subspecies of the finch. Same with his Galapagos turtles. But you know what, it doesn't matter what level we're on, the processes that bring about a new population that is identifiably a new race or breed or SPECIES are all the same. Just think, NN, stop blathering about your definitions.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined:
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The difference is academic and irrelevant. The processes that create breeds or races or "species" which are really subspecies, are all the same. The cats with the curled ears are not a breed or species in the historical sense. You are also of course emphasizing evolutionary advantage which I don't even mention. I figure if it exists as an extant healthy population we don't need to get into what advantages might or might not have brought it to that existence in order to discuss what I'm focusing on here. HOWEVER, I also dispute that tenet of the ToE, I think the idea of evolutionary advantage is completely unnecessary to the formation of new races, breeds, subspecies or SPECIES. Certainly it has to be able to survive in its environment but the theory posits a struggle that does not necessarily exist. There MAY be a struggle, there may be natural selection in some situations, but it is far from necessary in the development of new subspecies. The blue wildebeest probably split off from the black wildebeest a hundred or so years ago and formed simply by some limited number of the beasts walking off into a new region where they were reproductively isolated from the former herd. Or perhaps a lion attack split the herd and they ended up in different locations. It doesn't matter. There is no reason to suppose the new region posed any special problems as to its food sources or anything else. So its own peculiar characteristics developed due to its own new gene/allele frequencies that differ from those of the original population. Nothing else is needed to get a new breed or race, or SPECIES. ABE: That is, there need to be no adaptive advantage or disadvantage in the situation of blue or black wildebeest that affects their genetic expression, they simply display the fact that the genome of each Species (in the sense of Kind) is designed with many genetic potentials that allow it to form new races and breeds. /ABE ABE: The idea that evolution comes about by adaptive pressures, or advantage in the environment, AND the idea that mutations are the source of viable alleles, are both pure unverified theory. These are assumptions accepted because that's what the ToE says. But in reality what is actually OBSERVED is the formation of divergent populations by reproductive isolation; NOT an assumption. And the very method of isolation of a limited gene pool as the cause of such divergence is well observed in breeding, which is just the conscious version of what happens randomly in nature. These things ARE observed, but the mutations and the evolution by struggle are just the theory, the ToE that is believed without proof. /ABE
What you don't get, of course, is that I AM talking about the ToE, and these facts blow it to smithereens. Edited by Faith, : No reason given. Edited by Faith, : No reason given. Edited by Faith, : No reason given.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
In other words it's a good thing they can change the order of the DNA sequence and not do any real damage. Basically good design I'd say, that can survive such assaults on its integrity to the extent you all say occurs. A few more assaults on that same sequence might produce a different outcome though.
All assumption, all theory, all Creed. The reality is that mutations are mistakes that change things that were working perfectly well. If the DNA manages to go on functioning, hooray for the DNA. Meanwhile you hold on to this idea that a destructive process can destroy the sequence of a gene and produce something "helpful" given the right environment. Does probability enter into any of these suppositions?
No "mechanism that would prevent useful mutations from occurring?" Pretty hypothetical statement that. I'd suggest the improbability of it for one thing, given the fact that mutations are a basically destructive occurrence, interfering with the normal functioning of DNA. For another, the extreme rarity of such an occurrence, and in fact the iffiness of the evidence when you are able to trace it at all. Meanwhile there are those thousands upon thousands of known genetic diseases.
The difficulty of making the observations that I require? You mean because I said it takes thought, it's not all that easy to grasp? That's somehow a proof that it can't be a real case against the theory? This is strange logic indeed.
Then it sure is fortunate that I have made no such "demand," isn't it? On the other hand you all DO demand that those who disagree with the ToE should have it shoved down the throats of our children against our will. Go figure.
More theory, creed, assumption. This is sheer blindness to the fact of what mutations really are. It's a good thing the DNA design is hardy enough to withstand these frequent assaults on its integrity to the extent it can. But there is that assumption again, that theory, that fantasy, that says you can make a silk purse out of a sow's ear, I mean a useful mutation out of a deleterious one that pretty much destroyed a functioning gene, if the "right environment" happens to come along to make use of it. Of course you offer no evidence of such a thing, because it's all creed, assumption based on the theory. But really maybe it's more like this familiar scenario where it gives you a painful chronic skin rash but it also protects you against frostbite? That's the usual kind of thing we get from a "good" but "deleterious" mutation. You know, malaria protection in exchange for sickle cell anemia. Wonderful.
But again this is just based on the theory, with such a minuscule bit of evidence for it that it hardly exists at all.
What other evidence? You mean all those assumptions piled on assumptions? Don't know what you mean here.
I'm sorry, you've completely lost me. "Unknown source of beneficial genetic changes?" But of course I'm claiming that all beneficial genetic changes -- if we're talking about observable change from population to population at least -- that are known to occur are explained by the processes I'm laying out here. Nothing unknown about it. --although I wouldn't put the word "beneficial" in there because that's an artifact of the ToE and has nothing to do with what really happens in reality, which is that change occurs with the shuffling of gene/allele frequencies and in most cases the change is just as viable as the original population, no better, no worse. In a ring species there's no more or less advantaged or adapted species, they are all simply interesting variations on the genetic theme as it were.
Well you really HAVE lost me, I have NO idea what you are talking about now.
Seems to me it is VERY unlikely that any single mutations, that is, mutations possessed by single individuals, WOULD be passed on at all. As I said, only if you are assuming that all alleles were originally mutations can you suppose that mutations have anything to do with the formation of a new species. But anyway, again, this is pure assumption, that mutations have anything at all to do with the formation of species/subspecies, and that natural selection is always the reliable hero ready to save the day when things go a bit wrong. The ToE says it's so, therefore it is so.
WHAT "observed genetic diversity?" This is FICTION, PaulK. You say it is "observed," where is the evidence? Which dog breed has more genetic diversity than a mutt? Where's your vaunted Evidence? And don't give me that rabbits in Australia scenario which ended with someone questioning the facts in the story.
Getting anyone who is steeped in the ToE to see anything I have to say is not something I have any illusions about any more. The argument has been sufficient but the eyes are closed.
What's really odd here is that you all keep complaining I'm ignoring the evidence but what I've been getting from you is mostly theory and assumption, no evidence at all. Edited by Faith, : No reason given.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
I do not want to continue this discussion with you. But I have to correct this idiotic thing you are doing with the term "race." The way I am using it is perfectly correct to describe subspecies of any animal, and this was confirmed and in fact suggested as the correct term by dwise just a short while ago when he said I should not use the term "variety" to refer to animals but only to plants. Darwin used the term "race" to apply to animals too, it's the right word, you have a narrow contemporary bias on it. However, just because there must be such silly minds here, I will try to stick to the term subspecies.
GET A CLUE. You don't understand the argument I'm making and you don't even know the proper terms for things.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
Which is true exactly as I've presented it. The example of breeding is the only accessible example of how this has to happen to get the new traits of a new breed, and it's perfectly good as an example of what has to happen in the wild too. The alleles for other traits can't remain in the population, period. Edited by Faith, : No reason given.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
Why do you keep talking about phenotypic diversity? That has nothing to do with my argument. Of course you can get traits popping up in a wild population from time to time that make it more diverse at that level. Mutation isn't required, just the occasional expression of a rare recessive allele will do it. That's has nothing to do with my argument.
It won't be the gain of a new gene, only an allele for the gene that makes ear shape. But in any case this has nothing whatever to do with my argument.
Of course it doesn't mean anything. It's got nothing to do with what I'm talking about. It IS somewhat similar to Dr. Adequate's case of the curled-eared cat, which gets called a "breed" just for its ear apparently, which is also not what I'm talking about.
Yeah, and?
You really have NO idea what I've been arguing, at all. What do you mean "They" are necessarily "less diverse?" Within a generation or two of their isolation they could be much more diverse as new traits from new genetic combinations start appearing among them. But I'm not focused on the diversity of the phenotype, ONLY the fact that the GENETIC POTENTIALS reduce AS YOU GET THE DEVELOPMENT OF A NEW SUBPOPULATION. In new populations split off from old you have new gene/allele frequencies. Some alleles for some genes are MORE frequent, some less. This brings about some changes in the phenotype. Maybe the curly ears become more frequent. But it's only when the new group inbreeds for enough generations to begin developing a characteristic look to the whole population that we can talk about the formation of a new race or breed or subspecies. That's when it begins to look appreciably different from the other population, when the divergence between the two becomes evident, when the various traits of individuals that make the population diverse in the sense you are talking about start to blend into a trait picture shared by all the individuals, some disappearing, some spreading to all members etc. If the process goes on long enough you may even have a new species in the sense of a distinctively different population that cannot interbreed with the former population any more. Isn't that when you want to talk about speciation? A new species? What I've been trying to point out in this scenario is that there will be a loss of genetic material for the characteristic traits, a loss of competing alleles for those traits. That has to happen for those traits to become characteristic.
All quite true and all quite irrelevant to the point I've been trying to make. You are talking about phenotypic diversity, I am talking about genetic diversity, specific the loss of it as a POPULAIION acquires the haracter of a race or breed or subspecies. To get the second species in a ring species requires that the alleles for the new traits be more frequent and alleles for traits that are different from it stay behind in the old population. And so on around the ring. Ultimately a "true breed" may have ONLY those alleles for its characteristic traits and they may become homozygous or "fixed loci" while ALL alleles that are different from that character have been completely eliminated from the population. Complete elimination doesn't have to happen for the new species to exist, of course, there can be a few lingering old alleles that still pop up from time to time.
And so could I but it would interfere with the trait picture that characterizes the new population or new species. The point is that you have to eliminate the alleles for other traits to preserve the characteristic traits. This is what breeders do intentionally, nature does it randomly.
But we're not talking about increasing diversity, that's another subject, we're talking about creating a new subspecies or even species in which a new trait picture is formed that's different from the other populations of that Species, and that is what requires the overall reduction of genetic diversity. GENETIC diversity. GENETIC.
Surely the making of new species is what it is all about. It's about how there are four different kinds of finches discovered by Darwin, whole populations of them that have different habits from the other finch populations. It's about his Galapagos turtles which look different from those on the mainland they sprang from. What else could it be about? Supposedly it's about CHANGE, change in whole populations, not just change in individuals, which happens among human beings all the time, even from parents to children. What I'm talking about is change that comes to characterize a whole group, race, breed, subspecies, whatever you want to call it, a group, a population, that is isolated from the other members of the Species to inbreed long enough to develop its own peculiar characteristics. Again take the ring species, I'm talking about the kind of POPULATION-WIDE differences that exist between one species and another around the ring.
Dear nukeywukey, you really really aren't getting this at all. Down any path where the changes I'm talking about are occurring there has to ultimately be an end where no more variation is possible becaue there is no more genetic diversity left in that population. And since it's these paths that are definitive of evolution this clearly shows that macroevolution simply cannot happen. Edited by Faith, : No reason given. Edited by Faith, : No reason given.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
But what are you trying to prove by this? I'm really not getting your point. Yes a (putatively viable) mutation will add genetic diversity and if it's expressed also a new trait. There's nothing about that to challenge anything I'm saying.
This just seems like a semantic game to me, like Dr. A's examples. You get a new population that is distinguished by only one trait and call it a new breed or subspecies. OK, where do we go from there? I guess I could point out that for the population with the curly ears, the alleles for other kinds of ears are reduced or eliminated, which is the pattern I've been talking about. And if you keep the curly-eared wolves reproductively isolated from the rest of the population over many generations of inbreeding, their new allele/gene frequencies will probably change more traits than the curly ears (depends on the genetic diversity of the species to begin with and I don't know in the case of wolves. If it's high enough you should get the new traits). This would occur simply because it IS a smaller reproductively isolated population. It will certainly have different allele frequencies from the mother population. And that's the basis of microevolution. And it would have reduced genetic diversity as a result. The curly ear becomes just one of the traits, and its allele may even become fixed over time, while all the alleles for other kinds of ears disappear from the gene pool, along with the alleles for whatever other traits are becoming characteristic of the group, which is the process of reducing genetic diversity I'm talking about.
I would if I knew what to reconsider but I'm not getting what you are trying to prove here. If you want to try to prove that evolution continues even with increases in genetic diversity or that you can get distinctive new subspecies by such increases you'll have to come up with a few more examples. ABE: If you bred together all the cats with the curled ears, which are a pretty motley crew at this point, keeping them all reproductively isolated from all other cats, while inbreeding completely among themselves, I think then you might get a very interesting new breed that really would be a new breed, with a distinctive character all its own plus the curled ear. it would take many generations of inbreeding to do that. It would be really interesting to see what traits would emerge from the pool that has already been created. Of course my principle would apply, the traits that do emerge and become characteristic of the breed would be created from their own alleles, all alleles for other versions of those traits gradually disappearing from the breed. That's the necessary genetic reduction for producing a truly new breed. Edited by Faith, : No reason given. Edited by Faith, : No reason given. Edited by Faith, : No reason given. Edited by Faith, : No reason given.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
Where did I say "NEW GROUPINGS?" You can create new "groupings" a lot of different ways. I am talking about creating a new SUBSPECIES with its own gene pool. That takes reproductive isolation over many generations. That you cannot create without reducing GENETIC diversity. Again you use "diversity" ambiguously which shows you are missing the whole point.
They are not what is required to deal with my argument. They almost seem like a silly simplistic parody. You are simply not understanding my argument although of course you think you are. I keep telling you its not easy to grasp. It isn't. It's simple enough but it's also tricky. You don't have a clue about it yet.
Dr. A's examples completely miss the point too. Neither of you understands this argument. Edited by Faith, : No reason given.
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Faith ![]() Suspended Member (Idle past 761 days) Posts: 35298 From: Nevada, USA Joined: |
Kindly reproduce the part of the post where you believe you did that.
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