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Author Topic:   The End of Evolution By Means of Natural Selection
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 61 of 851 (552150)
03-26-2010 9:23 PM
Reply to: Message 58 by Faith
03-26-2010 2:04 PM


... cards and populations and average fitness
Hi again Faith, hope you are able to get to this ...
so that it's hard to get across what seems to me to be the much more common scenario I've been spelling out -- that an already-present complement of alleles is split between the populations and it is this that brings about the differences between the two as they go their separate ways mixing their genes in isolation from each other. It's the already-present alleles that "are no longer shared" between the populations, not mutations. The already-present alleles are sufficient to establish two different varieties without any help from mutations, and even to establish separate species according to the definition that they can no longer interbreed.
In other words, in order to have an artificial situation where alleles are lost through various means, causing a reduction in the overall number of alleles in a population, you chose to ignore the mechanism that provides new alleles. Populations cannot live in isolation from mutations, as the major source of mutations is internal, and present in every single reproduction.
And you've also got one or both of these populations suffering from a disaster which could cause a bottleneck, or a predator or disease, all reducing the population size and of course these reduce genetic diversity just as natural selection does or migration of a small portion of the population as in ring species and so on and so forth, which is where I've been trying to focus from the beginning.
When you get a smaller number from a population isolated that's when you get reduced genetic diversity.
One of the problems with this, is that if the number of alleles were reduced by such stochastic means, this just means that more new mutations have more opportunities to get passed on to following generations, including mutations that would be considered deleterious in the original populaiton. The reduction in competition works in their favor.
Think of it like this: you have a deck of cards, and the average value is 7. Cut the deck ~50:50 and the chances are that the average value is still 7. Cut it into a small population and a large population, and the large population is more likely to have the average value still 7, while the small population may have a higher or lower value.
Now let's pretend that these values represent fitness. In every "generation" we discard the lowest 10% of the cards and draw new cards from a new deck to replace these plus 1 new card for population growth in the new ecology. Over time you will tend to replace more low cards with higher value cards, but the population as a whole will tend to have an average value of 7 after many generations, meaning that on average they are just as fit and diverse as the parent population was.
The basic problem you have, is that you are focused on one single allele, claiming that it is forcing out all competition, and choosing to ignore the next new allele will be trying to do the same thing, leaving evolution in a constant state of flux.
When you get a smaller number from a population isolated that's when you get reduced genetic diversity. It's what has to happen in natural selection and it's what happens in speciation.
No.
Speciation does not result in a loss in genetic diversity, it occurs due to an increase in diversity in the parent population: the parent population has become so diverse that it can occupy one or more ecologies the ancestral populations were not able to occupy in previous generations.
Or a population overruns it's ecology and forces marginal individuals into marginal ecologies. These then adapt or perish, but the original diversity is still present in the parent population, and all the adaptation in these outcast populations are to adapt to their new ecology, and again more new mutations are "beneficial" to them in this situation, because there are more opportunities for them.
... and since these are intrinsic to evolution then evolution depends on reducing genetic diversity in order to get a new variation or species and you can see that this chain of events MUST be self-limiting.
Again, this is backwards thinking: speciation occurs when there are new opportunities and new mutations\variations that allow a population to take advantage of the opportunities.
Enjoy.

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This message is a reply to:
 Message 58 by Faith, posted 03-26-2010 2:04 PM Faith has not replied

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


(1)
Message 62 of 851 (552155)
03-26-2010 9:58 PM
Reply to: Message 58 by Faith
03-26-2010 2:04 PM


Re: (Subbie) Am I ignoring reproductive isolation?
Hi Faith,
I don't know why you went so far back and responded to Message 15, but what you were saying at the time and what I was responding to was that any evolution can only result in reductions in variation. As everyone's been telling you, variation can increase or decrease.
OK, I can see that mutation appears to be the explanation for all change in the minds of evolutionists here...
The reason I mentioned mutation is that the sum total of all alleles in a population is the amount of variation, and only mutation can increase the number of alleles. Natural selection can affect allele frequency, and indeed one way to define evolution is as changing allele frequency over time, but only mutation can increase the number of alleles and thereby increase the amount of variation.
The reason people are bringing up mutations isn't because they think it is the source of all evolutionary change, because obviously it isn't the only source. They're bringing it up because it is the only way to increase variation. Mixing and remixing the same set of alleles can create unique combinations of alleles that didn't previously exist, but it doesn't change the pool of existing alleles at all.
Almost no reproduction is perfect. Even people have mutations. The average number of mutations per person is usually estimated at between 10 and a hundred. Ignoring mutation might make it easier to claim that variation can never increase, but the real world has spoken.
--Percy

This message is a reply to:
 Message 58 by Faith, posted 03-26-2010 2:04 PM Faith has replied

Replies to this message:
 Message 65 by Faith, posted 03-27-2010 1:41 AM Percy has replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 63 of 851 (552166)
03-27-2010 1:18 AM
Reply to: Message 41 by Faith
03-26-2010 3:10 AM


Re: (Subbie) Am I ignoring reproductive isolation?
My understanding of speciation is that, just as with domestic selection, the selected trait is isolated from other alleles for that trait so that it can disperse through the new population down the generations and thus come to characterize the new species. If the alleles for different kinds of beaks were not eliminated you would not have this new species.
And yet no matter how fast and furiously you spin your words and juggle the goalposts, the result is still a new variety of finch.

This message is a reply to:
 Message 41 by Faith, posted 03-26-2010 3:10 AM Faith has replied

Replies to this message:
 Message 66 by Faith, posted 03-27-2010 1:42 AM Dr Adequate has replied

  
subbie
Member (Idle past 1255 days)
Posts: 3509
Joined: 02-26-2006


Message 64 of 851 (552168)
03-27-2010 1:38 AM
Reply to: Message 41 by Faith
03-26-2010 3:10 AM


Re: (Subbie) Am I ignoring reproductive isolation?
Faith writes:
If the alleles for different kinds of beaks were not eliminated you would not have this new species.
But this does not eliminate the alleles from the other species of finches, which still exist. Thus, an increase in the total variety.
A beak type got selected for its usefulness with a particular kind of function, and that got passed on and came to characterize a whole population because the alleles for the other beak types were eliminated from the reproductive pool.
Given that Darwin himself collected examples of the different species, this is obviously not what happened. The different beak types continue to exist and variety increases.
It's not exactly that there were "changes in alleles"
Actually, despite your wishes to the contrary, it is exactly like there were changes in alleles.
The principle I'm hammering away at does hold up you see.
It doesn't, but I'm quite confident that you don't see, and never will.

Ridicule is the only weapon which can be used against unintelligible propositions. Ideas must be distinct before reason can act upon them; and no man ever had a distinct idea of the trinity. It is the mere Abracadabra of the mountebanks calling themselves the priests of Jesus. -- Thomas Jefferson
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 Message 41 by Faith, posted 03-26-2010 3:10 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 65 of 851 (552170)
03-27-2010 1:41 AM
Reply to: Message 62 by Percy
03-26-2010 9:58 PM


I do not deny variation. Sheesh
Hello Percy,
I'm going through all the posts on this thread in order. I may have to give this up eventually but that's the plan for now and that's why I answered your message 15. I'm still working on 18 but need a break from the intensity.
I'm also not going to answer this post of yours until later, except to say one thing: I have never said that variation cannot increase. For one thing I'm focused on genetic variability, not variation.
More later.

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 Message 62 by Percy, posted 03-26-2010 9:58 PM Percy has replied

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


Message 66 of 851 (552171)
03-27-2010 1:42 AM
Reply to: Message 63 by Dr Adequate
03-27-2010 1:18 AM


I'm also not ignoring VARIETIES. I'm EXPLAINING them. Sheesh
Yes and we get that new variety of finch by subtracting alleles that don't fit the blueprint.
I'll get to YOUR other posts eventually too. All in good order.

This message is a reply to:
 Message 63 by Dr Adequate, posted 03-27-2010 1:18 AM Dr Adequate has replied

Replies to this message:
 Message 68 by Dr Adequate, posted 03-27-2010 2:06 AM Faith has replied

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


Message 67 of 851 (552172)
03-27-2010 1:46 AM
Reply to: Message 64 by subbie
03-27-2010 1:38 AM


finches' beaks
Man you guys deny the obvious, how domestic selection works and how Darwin based his natural selection on it, and you accuse me of ignoring things I've answered twenty times already and accuse me of not seeing things I've already taken account of. It's YOU who can't see. Give me time to get to it and I'll EXPLAIN why you continue to get varieties, AND explain the difference between that and genetic variability which has obviously escaped you.
But to be fair, I expected this.
Talk to you more later.
Cheers.
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 64 by subbie, posted 03-27-2010 1:38 AM subbie has not replied

Replies to this message:
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Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 68 of 851 (552175)
03-27-2010 2:06 AM
Reply to: Message 66 by Faith
03-27-2010 1:42 AM


Re: I'm also not ignoring VARIETIES. I'm EXPLAINING them. Sheesh
Yes and we get that new variety of finch by subtracting alleles that don't fit the blueprint.
And since these alleles were not subtracted from the gene pool of the parent species, what we have is speciation with no net loss of genetic variation.
Indeed, since the new allele must have arisen at some point, the total process involves an increase of genetic variation.

This message is a reply to:
 Message 66 by Faith, posted 03-27-2010 1:42 AM Faith has replied

Replies to this message:
 Message 70 by Faith, posted 03-27-2010 3:23 AM Dr Adequate has replied

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


Message 69 of 851 (552176)
03-27-2010 3:14 AM
Reply to: Message 18 by Rahvin
03-25-2010 5:17 PM


Rahvin 2 part 3
In the bacteria experiment, mutation increases diversity. The antibiotic exposure selects, by eliminating non-resistant bacteria and thus reducing total current diversity.
Yes. This is evolution by natural selection. You get a new phenotype, this non-resistant bacteria and you get it by losing genetic diversity. Yes. What I’m talking about. Yes.
The population, when allowed to grow again, will again increase in diversity due to mutations - such that a subgroup of the main population may develop resistance to a different drug, and so on.
I get the impression you are simply assuming it increases in diversity due to mutations rather than reporting on something you’ve actually observed.
It's selection and isolation that bring the desired trait to expression in the phenotype,
Wrong. Evolution is not reactive. The resistance trait (in our example) must already exist in the population before the antibiotic is used.
Whoa, simmer down. You are just jumping on imprecise wording, which in a subject like this is going to occur rather frequently, so give a person a break. I’ve said this in so many ways by now you ought to know what I mean anyway. I’m simply repeating the FACT that selection and isolation, NOT MUTATION, are what bring about the new phenotype that characterizes a whole new population. OF COURSE the phenotype must already be there. I’m talking about how it comes to characterize a whole new population/variation/breed/species. Evolution by natural selection, remember?
The population does not generate resistance as a response. Until the antibiotic is used, the resistance is simply a random mutation that confers no benefit and thus enjoys no greater representation in the population as a whole than any of the other uncounted mutations in a diverse population. Only when the selective pressure of the antibiotic is introduced does the already-existant mutation suddenly confer a survival advantage to the subgroup, and the trait will rapidly increase in freqency as the competition is killed off by the antibiotic.
Rahvin, in this respect you’re preaching to the choir again. You yell that I’m wrong but I meant the same thing I’ve been saying all along and that is exactly what you are saying here about how selection works. As I’ve said from the beginning, it doesn’t matter where the new variation comes from -- a mutation or a rarely expressed allele or a normally occurring allele for that matter -- if it is selected it will rapidly increase in frequency as the competition is [eliminated] from its reproductive opportunities. You’ve got a mutation that comes to characterize a whole population by this means, exactly what I’ve been talking about. In order for it to come to characterize the population the competition must be eliminated, reducing genetic diversity. Evolution by natural selection.
drug resistance in the case of bacteria, and this always involves decreased genetic variability. At least you haven't shown me how it doesn't.
The selective pressure reduces extant genetic diversity by killing off large numbers of a diverse population.
Don’t just rush on to the mutation part. This is the part I’m trying to keep in focus.
But mutation continues to increase diversity even after the population ahs been reduced (just like it did when we started with zero diversity in a population of one).
I thought what you got was a population of clones with the occasional drug resistant type, not the sort of increase in genetic diversity you seem to be implying now.
The process doesn't stop. Variation continues, unimpeded.
There is no reduction in the possibilities derived from mutation guided by natural selection.
You’ve asserted this many times without proving it.
At no point to we reach an evolutionary "endpoint" where no more change is possible.
No, in most populations you WOULDN’T reach that point, so it’s a straw man to imply I’ve said any such thing. I’m talking about a TREND and it IS a trend that is demonstrable. Go look at the links in the OP. It’s also demonstrated in endangered species — bottleneck is merely an extreme version of the very same processes of selection and isolation, ALL of which reduce genetic diversity in the process of forming new population characteristics. I’ve also suggested that sampling the DNA in the series of populations in a ring species would prove the point empirically.
There may, hypothetically anyway, be no "reduction in the possibilities derived from mutation," but when you add "guided by natural selection" you are implying something that can't in fact happen. Natural selection "guides" by doing what I've been describing, by eliminating all that variation mutation has brought about so that the selected variant can come to characterize the population.
Not all. Some. Natural Selection is not some rampaging genocidal agent running around killing everything.
Natural selection is simply the process by which beneficial traits tend to increase in a population because those who possess those traits will survive to reproduce more often than those with non-beneficial traits. More often does not necessarily mean to the exclusion of. In a given environment, animal A may be "better" adapted than animal B, but that doesn't necessarily mean B will go extinct.
You are again failing to grasp what I’m trying to say here so let me try to clarify.
One form of selection is for a trait to merely increase and spread through a population, but even in that case it does so by replacing other alleles for the same trait. How could it be otherwise? The trait in question can’t come to characterize the population unless it does this. All the competition has to go. Or perhaps be preserved in the recessive position or something like that. So that if it is strongly selected eventually down the generations ALL competing alleles will be eliminated from the population, just more slowly than they would be if there were a more immediate drastic selection pressure. It doesn’t have to be total, that’s a matter of how severe the selection pressure is. But the trend is undeniable. You’ve GOT to replace the unhelpful alleles with the helpful one. That’s what selection DOES.
There is no getting around this, selection and isolating processes ALWAYS reduce genetic diversity. Always. If you keep your sights on the phenotypic changes being brought about, which is all too easy to do, you can manage not to notice that this is in fact what is going on at the level of the genotype.
You switched your focus to the animal here and lost track of the genetic situation. B isn’t going to go extinct, and I haven’t suggested such a scenario either. Through preferential reproduction, over generations eventually ALL the individual animals will HAVE the selected allele — B’s offspring will eventually have it if B does not, and that’s simply because it didn’t get passed that far in the population yet but assuming the reproductive selection holds up eventually ALL the members of the population will have it. It takes time for a selected allele to work its way through the whole group. It COULD go pretty fast if it’s a matter of protection against a predator or something like that, so that the individuals that don’t have it will simply be eaten and those with it will form the new population. But I’m using an example of a less drastic selection, a selection that confers an advantage but isn’t life or death, such as the frog’s fly-catching mutation that Pink Sasquatch brought up on the original thread.
The fact that great variety exists in nature is a very good thing, but this doesn't change the fact that when evolution occurs in a population it HAS to reduce genetic diversity. That's the only way you get a new variety.
False. COmpeltely false.
I’ve PROVED it, Rahvin. You do NOT get a new dog breed unless you separate it from all genetic input that doesn’t contribute to the type you want.
evolution happens when an existing population diversifies and branches off into distinct sub-populations. That doesn't necessarily involve the extinction of any of the child populations or even the disappearance of the parent.
Nor did I say it did, for heaven’s sake! What it DOES involve is the reduction of the genetic diversity in any subpopulation that is appreciably smaller in numbers than the parent population. (A larger subpopulation may retain the basic genetic and phenotypic character of the parent population.) This is because alleles are likely to have been left behind in the parent population, and CERTAIN to have been left behind if the subpopulation is VERY small. It ALSO involves the development of a new phenotypic characteristic to the new subpopulation. This is the result of the reduction in genetic diversity which allows the new frequencies of alleles to be expressed, particularly for alleles formerly suppressed in the parent population to be expressed, because the competition has been removed.
Diversification typically happens due to environmental changes, as random inherited mutations suddenly become beneficial or detrimental. Often this happens when some of a given species migrates to a new area, and thus a new environment with different selective pressures. In this case, even though the migratory population will end up distinct from its parent, the parent population still exists, and thus diversity is increased.
This makes no sense. The continued existence of the parent population does NOT increase diversity — not genetic diversity in any case.
Also, the fact that the alleles that are lost to the subpopulation remain in the parent population is a point that only obscures the fact that the natural selection that is bringing about the new phenotype and reducing the genetic diversity is going on in the subpopulation. For THAT population the diversity is reduced, and it's ONLY that population that is under discussion. It's the one that shows that natural selection and migration and other ways populations get reduced and isolated produce new phenotypes BY reducing genetic diversity. It doesn't matter what remains in the parent population. It's irrelevant to the point.
The split has brought out new phenotypes in the new population but this is because the genetic diversity has been reduced there. THIS IS THE GENETIC LAW I’M TALKING ABOUT. What has happened in this situation is that the migrated population, usually appreciably smaller than the parent population, develops a new phenotype that sets it apart from the old population. It does this because it has reduced genetic options compared to the parent population. It takes this reduction to bring about the new characteristics. I know I’m repeating myself but since you never seem to notice I’ve said it twenty times already I have to repeat it yet again.
I have to postulate that there used to be much much more variability in all species than there is today in most species, BECAUSE of the evolution that has been going on creating new varieties (or "species" if they can't interbreed with their parent population) over millennia. Some species retain enormous variability nevertheless -- dogs for instance. The most amazing varieties of dogs have been brought about and yet they can still interbreed -- THAT's enormous built-in variability there. But other species don't have that much variability, or have lost it in their successive branchings down the centuries.
Provide evidence that other species do not possess the capacity to be bred as dogs have or retract.
Cheetah. Overhunted seal. Overhunted eagle. Guinea pigs. Raccoons. Bears. No way are you going to get the incredible range of viable variations you get with dogs from any of these animals.
I'll do one better though: we can breed all manner of plants and animals with a very great degree of diversity. Do you have any idea how different the corn, banannas, grapes, cows, pigs, or really any domesticated animal or plant has diverged from the original natural stock? How much diversity we still have amongst those populations while retaining the ability to interbreed?
I have no doubt there are many species with lots and lots of remaining genetic diversity and nothing I’ve said implies otherwise. You can in fact breed them for quite some time into the future without getting anywhere near genetic depletion. That doesn’t contradict the fact that selected variation is ALWAYS accompanied by a corresponding reduction in genetic diversity -- not depletion, not anywhere near depletion, but reduction. However, I’m not sure it’s quite right to compare plants with animals in this respect.
Which organisms, precisely, lack the potential to be bred to extreme degrees of diversity, and how do you know this?
I know it simply from the fact that we do have severely genetically reduced animals, endangered species. You perhaps keep them off in a separate compartment in your mind as I think evolutionists tend to do, but I see them as representative of selection processes. Bottleneck is simply a more rapid version of all the selection processes.
Consider the dog example while we're at it. Every breed of dog MUST show reduced genetic variability compared to its population of origin because if you want it big you're going to have to eliminate everything that tends to smallness, if you want it good natured you have to eliminate everything that breeds for ferocity, and so on.
Reduction in the frequency of one trait does not necessarily reduce the frequency of all other traits in teh same organism, Faith.
I have not said it does and this has nothing to do with what I AM saying. I'm not interested in variation or frequencies AS SUCH, my point is what happens genetically to a population as new phenotypes are being formed in it, on out to speciation. What's happening in other populations is another subject. (However, "frequency of trait" isn't quite the right expression, so I'm not sure what you have in mind).
Just look at all of the "small" dogs we have, their differences in fur, coloring, temperament, intelligence, etc. You can breed for a specific result ("bigness" or "smallness") and still increase total diversity.
This isn’t an increase, it’s simply the preservation of whatever other traits were also in the same animals you chose to breed from. When you breed animals you breed WHOLE animals with their whole collection of genes and whatever alleles come with them, you can’t just select smallness and not get all the other traits the bred animals possess. When I speak of a single allele it is to show what selection does. The same thing happens if a thousand alleles for a hundred genes are simultaneously selected by breeding the animal that possesses that particular combination. As long as you keep mating it with other animals with the same characteristics and eliminate characteristics that are different you’ll end up with a new breed with reduced genetic diversity compared to the parent population. GENETIC LAW.
Dogs as a species have enormous genetic variability but a particular dog variety or species has to have very little.
You mean a sub-population will have less diversity than the total population?
Why would we ever assume otherwise, Faith?
If A = B + C, B and C will always each be less than A.
Seems to me you’ve been disagreeing with me about this all along. You argue and argue and argue with exactly the same point in different words and then suddenly I say it a certain way and you agree.
You are ELIMINATING alleles in order to bring about your favored breed. Assuming that natural selection operates in a similar fashion in nature, that's what has to happen there too. You are not going to get a new variety, breed or species without a loss of genetic variability. This is really a law of genetics.
This is really a case of you not understanding genetics. You can reduce the frequency of a single trait without affecting the frequency of other traits, including the appearance of new traits.
What I just said above that you are so strenuously disagreeing with is exactly what I said above that but in different words that you agreed with. What is the problem here? To get a new breed you eliminate alleles is the same thing as saying A subpopulation will have less genetic diversity than the total population. What IS the problem here? What? You are making no sense. You seem to be objecting just for the sake of objecting.
You can reduce a population of bacteria to one individual, meaning zero diversity, and end up with a highly diverse population that has even developed new traits like antibiotic resistance.
Your premise is utterly false.
You just agreed with it two lines above!! I was merely restating the same concept about breeding in different words and now you are going on and on about a single bacteria?
Here, let me try to sort this out.
You think that your example of getting new traits like antibiotic resistance in a whole population of bacteria contradicts my statement that you have to reduce genetic variability to get a new breed.
First of all you can’t switch from dogs to bacteria as if they were equivalent. What I said is true for dogs; I have no idea if it’s also true for bacteria. But don’t scream at me when I’m talking about dogs because bacteria behave differently.
Second you are confusing the process of bringing about a new phenotype (the mutation) with the process of that phenotype's being the basis for a new population. I seriously doubt that you are getting an increase in genetic diversity as that population grows, but if you are then bacteria simply have nothing in common with dogs.
I don’t know if anything was gained by working my way through this long post but I did it and I’m going to leave it at that.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
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Replies to this message:
 Message 76 by Percy, posted 03-27-2010 7:49 AM Faith has replied

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


Message 70 of 851 (552177)
03-27-2010 3:23 AM
Reply to: Message 68 by Dr Adequate
03-27-2010 2:06 AM


Re: I'm also not ignoring VARIETIES. I'm EXPLAINING them. Sheesh
Yes and we get that new variety of finch by subtracting alleles that don't fit the blueprint.
And since these alleles were not subtracted from the gene pool of the parent species, what we have is speciation with no net loss of genetic variation.
Indeed, since the new allele must have arisen at some point, the total process involves an increase of genetic variation.
Well, Dr. A, you write short posts so I'm tempted to answer them even though I'm trying to stick to my plan of getting through the whole thread in order.
I'm not talking about "net loss." It doesn't matter what remains in the parent population (or the overall population that includes the subpopulations either) as far as the point I'm trying to make goes.
I'm making a point about how you don't get new phenotypes without a loss of genetic diversity in the population that is becoming characterized by a new phenotype. The parent population in question is not developing a new characteristic phenotype. If it is then it has to be losing alleles too. It doesn't matter if they're lost by being left behind in the parent population or lost by disaster, they still have to be lost from the new population if a new phenotype is to emerge.
The evolving population is losing genetic diversity in the process of developing its new characteristics that differentiate it from the parent population.
I'm talking about a process, and the amount of variation OR variability elsewhere is irrelevant to this process. In this process genetic variability is NECESSARILY lost. You don't get a new phenotype UNLESS it is lost. You don't get speciation UNLESS it is lost.
Even if the allele were originally a mutation, when it gets selected OTHER alleles for the same trait have to be eliminated for it to spread in the new population and bring about a new phenotype.
Edited by Faith, : No reason given.
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 68 by Dr Adequate, posted 03-27-2010 2:06 AM Dr Adequate has replied

Replies to this message:
 Message 71 by Dr Adequate, posted 03-27-2010 4:06 AM Faith has replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 71 of 851 (552179)
03-27-2010 4:06 AM
Reply to: Message 70 by Faith
03-27-2010 3:23 AM


Re: I'm also not ignoring VARIETIES. I'm EXPLAINING them. Sheesh
Even if the allele were originally a mutation, when it gets selected OTHER alleles for the same trait have to be eliminated for it to spread in the new population and bring about a new phenotype.
Well yes. Fixation of an allele involves he loss of other alleles.
Where do you want to go from here? Remember, your goal is to deny evolution, not to say things that every biologist knows to be true simply by definition.

This message is a reply to:
 Message 70 by Faith, posted 03-27-2010 3:23 AM Faith has replied

Replies to this message:
 Message 72 by Faith, posted 03-27-2010 4:12 AM Dr Adequate has replied

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


Message 72 of 851 (552180)
03-27-2010 4:12 AM
Reply to: Message 71 by Dr Adequate
03-27-2010 4:06 AM


Re: I'm also not ignoring VARIETIES. I'm EXPLAINING them. Sheesh
Where do you want to go from here? Remember, your goal is to deny evolution, not to say things that every biologist knows to be true simply by definition.
Actually, the defeat of evolution IS by facts that every biologist knows to be true about evolution, only they deny them when they are brought into that context and affirm them when they can fit them into their evolutionist assumptions.
What I'm arguing OUGHT to be easily recognized, but check this thread -- it's being fought tooth and nail, this very ordinary obvious truth. Weirdly misunderstood, weirdly twisted.
That's because I'm bringing out its implications which are normally overlooked.
Evolutionists simply automatically stick mutation in there to counter the implications of this obvious ordinary fact so my job is to try to pry you all loose from that facile and false connection.
Need lots of rest for this task. Good night.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 71 by Dr Adequate, posted 03-27-2010 4:06 AM Dr Adequate has replied

Replies to this message:
 Message 73 by Otto Tellick, posted 03-27-2010 6:11 AM Faith has not replied
 Message 74 by Dr Adequate, posted 03-27-2010 7:04 AM Faith has not replied

  
Otto Tellick
Member (Idle past 2331 days)
Posts: 288
From: PA, USA
Joined: 02-17-2008


Message 73 of 851 (552184)
03-27-2010 6:11 AM
Reply to: Message 72 by Faith
03-27-2010 4:12 AM


Re: I'm also not ignoring VARIETIES. I'm EXPLAINING them. Sheesh
Hi Faith -- nice thread overall. I admire your stamina.
Faith writes:
What I'm arguing OUGHT to be easily recognized, but check this thread -- it's being fought tooth and nail... That's because I'm bringing out its implications which are normally overlooked.
On the contrary, your arguments are "being fought tooth and nail" because you are overlooking the implications of everything that is normally, frequently observed, and even the implications of your own statements.
As I reviewed this thread, it seemed to me that Phage0070 came closest to getting through to you -- you at least admitted that you were trying (but struggling) to understand what he said -- but his last post (at Message 23, with the neat graphics) is one of those you haven't managed to reply to yet. It may be that his first graphic doesn't quite capture the position you're trying to articulate here, but the second graphic clearly shows why your position is untenable.
The point would be even clearer if that picture is extended to the size of the populations we usually look at, and is drawn to show the geographic and other divisions that separate sub-trees at lower levels, to demonstrate how speciation works.
In your reply to Phage0070's first post (at Message 19), you repeatedly show the crux of your problem:
I'm not sure I'm following you here. I've been keeping my focus as much as possible on a SINGLE mutation (or allele) for the sake of simplicity...
OK, a source of confusion for me is that you have so many different variations going on whereas I've been trying to keep the focus on one at a time...
The genetic diversity in EACH of those "bloodlines" DOES necessarily trend toward zero AS LONG AS THEY MAINTAIN ISOLATION FROM OTHER LINES. You have to keep the focus on the SINGLE line that is evolving, even if there are three or five separate such lines...
I did have to take this step by step because it was hard for me to follow, but now I think I can say that the problem here is that you are treating the number and variety of "grandchildren" as a collection rather than as a line of evolution.
The problem here is that, although you seem to recognize that mutations occur, and that this creates distinct blood-lines, you are basing your position about the "wrongness" of evolutionary theory on two mistakes:
1. You apparently want to limit the scope of the theory, forcing its assertions to apply only within one or another small, specific sub-population (where, as commonly observed and agreed, there is in fact less variability than you find in a larger population). But the theory of evolution is supposed to cover the relationship between a common ancestor and all the varied descendants from that ancestor -- not just one of them at a time.
2. You seem to be suggesting (especially in the third snippet of that last quote-box) that as you focus in on one or another specific sub-population, further mutations in the offspring of that set just stop happening, or can just be ignored, or something like that. This is ridiculous.
I can understand that you need to be selective about the posts you respond to; if you have to choose between Phage0070 and me, I think I'd rather see you reply to him -- think of me as just an extension of him. (yes, us evolutionists tend to stick together... )
Edited by Otto Tellick, : clarified reference to quotation in the paragraph labeled "2."

autotelic adj. (of an entity or event) having within itself the purpose of its existence or happening.

This message is a reply to:
 Message 72 by Faith, posted 03-27-2010 4:12 AM Faith has not replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 74 of 851 (552185)
03-27-2010 7:04 AM
Reply to: Message 72 by Faith
03-27-2010 4:12 AM


Re: I'm also not ignoring VARIETIES. I'm EXPLAINING them. Sheesh
Actually, the defeat of evolution IS by facts that every biologist knows to be true about evolution, only they deny them when they are brought into that context and affirm them when they can fit them into their evolutionist assumptions.
Paranoia is not an attractive trait.
May I suggest an alternative that you've missed --- that the reason that every biologist disagrees with you (a non-biologist) about biology is in fact because they know more about biology than you do.
What I'm arguing OUGHT to be easily recognized, but check this thread --
I have in fact been reading it. This is why I'm so certain that you're talking blithering nonsense.
Evolutionists simply automatically stick mutation in there to counter the implications of this obvious ordinary fact so my job is to try to pry you all loose from that facile and false connection.
The reason that evolutionists include mutation in any account of genetics is that it exists. This is neither "facile" --- whatever you mean by that --- nor "false", and there is nothing whatsoever you can say that will prevent us from knowing it.
I can see why creationists would wish that it didn't exist, or at least that you could stop people from knowing that it exists, but you can't.
Need lots of rest for this task.
You'd find a simple statement of the truth to be a lot quicker and less fatiguing. But, of course, also less agreeable to your religious beliefs.
Edited by Dr Adequate, : No reason given.

This message is a reply to:
 Message 72 by Faith, posted 03-27-2010 4:12 AM Faith has not replied

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 75 of 851 (552186)
03-27-2010 7:37 AM
Reply to: Message 65 by Faith
03-27-2010 1:41 AM


Re: I do not deny variation. Sheesh
Faith writes:
For one thing I'm focused on genetic variability, not variation.
So am I. I defined variation as the sum total of all alleles in a population. I defined an increase in variation as an increase in the number of alleles in a population. If you're defining variation differently let us know.
I'm also not going to answer this post of yours until later, except to say one thing: I have never said that variation cannot increase.
Yes you did say that variation cannot increase. This is you from Message 1:
Faith in her opening post writes:
My argument is that natural selection and genetic drift, all the processes that select or isolate a portion of a population, do bring about the change called evolution but also always reduce genetic variability, which is the opposite of what evolution needs.
I just saw your answer to Subbie, so here's another quote from your Message 1:
Faith in her opening post writes:
I've been wanting to see if I can do a better job on my original topic here: Natural Limitation to Evolutionary Processes . As I've reread that old thread I see I got overwhelmed and defensive and didn't do a very good job of thinking through my answers.
People who make many simple errors draw many responses because everyone rushes to reply thinking, "This confusion should be a simple matter to clear up." Many people are responding to the exact same points. Responding to every reply under such circumstances isn't realistic.
There's a simple alternative available now. If you look at the bottom of any response to one of your messages you'll see that it says either "Faith has not yet responded" or "Faith has responded." This text is actually a link, and if you haven't yet replied to the message then if you click on this text it will change to "Faith acknowledges this reply." This lets the person know that you've read his message but don't feel it necessary to respond.
--Percy

This message is a reply to:
 Message 65 by Faith, posted 03-27-2010 1:41 AM Faith has not replied

  
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