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Author Topic:   A New Run at the End of Evolution by Genetic Processes Argument
PaulK
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Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 134 of 259 (770997)
10-16-2015 6:14 PM
Reply to: Message 131 by Faith
10-16-2015 5:58 PM


Re: Adding alleles prevents evolution from occurring
No, it isn't. The variations will be smaller (so that they would likely be acceptable) and there is no buyer and no selling.

This message is a reply to:
 Message 131 by Faith, posted 10-16-2015 5:58 PM Faith has not replied

  
PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 143 of 259 (771019)
10-17-2015 4:46 AM
Reply to: Message 115 by PaulK
10-16-2015 10:39 AM


Re: Faith doesn't get it
Faith claims:
If subpopulations form from the subpopulations, as in a ring species, that line of possible variations can ultimately reach genetic depletion, beyond which any further evolution is impossible for lack of the genetic fuel as it were.
But as I have shown this is false. Evolution slows down as variation declines but it will not stop.
And
What this implies is that the genome of each species defines the limit of that species' possible variations, beyond which no further evolution is possible.
Which is the same falsehood.
In reality "genetic depletion" is never seen to result from selection and will not result from normal drift. It is only the bottlenecks produced by severe population loss, or by breeding practices that are seen to produce such problems. The problems are largely a result of "linkage" - bad alleles close to good, which tend to be transmitted together. Natural selection, with it's slower pace has more opportunities to break the link and lose the bad (which will be selected against)

This message is a reply to:
 Message 115 by PaulK, posted 10-16-2015 10:39 AM PaulK has not replied

  
PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 144 of 259 (771020)
10-17-2015 6:47 AM
Reply to: Message 142 by Faith
10-17-2015 12:05 AM


Re: Some "intelligent" questions
Faith, is it really that important that people agree with you - even if you happen to be wrong?
One of your biggest problems here is that many of us care about the truth and you just want to drive a bulldozer over all that. It's certainly the reason for the most recent Admin intervention.

This message is a reply to:
 Message 142 by Faith, posted 10-17-2015 12:05 AM Faith has not replied

  
PaulK
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Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


(3)
Message 150 of 259 (771035)
10-17-2015 4:22 PM
Reply to: Message 149 by Faith
10-17-2015 3:49 PM


Re: Some "intelligent" questions
No Faith, all you have is an argument that you are desperate to believe.
You are unable to answer the objections and because you cannot you retreat into blind belief. And make up excuses to hide from the truth.
And that is why you fail to convince anybody.
The fact that you can't defend your argument may convince you of its truth. But it's hardly going to convince anyone else.

This message is a reply to:
 Message 149 by Faith, posted 10-17-2015 3:49 PM Faith has not replied

Replies to this message:
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PaulK
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Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


(3)
Message 166 of 259 (771078)
10-19-2015 4:54 PM
Reply to: Message 131 by Faith
10-16-2015 5:58 PM


Re: Adding alleles prevents evolution from occurring
quote:
It's exactly the same situation as having your golden retriever puppy show up mottled gray or your Freisian colt chocolate brown. They violate the breed and can't be sold.
To give a more detailed reply to this nonsense.
Firstly there is no way of "violating the breed". As I pointed out long ago, species are not artificially selected breeds. There is no set of required or forbidden traits, only those which the species actually has or does not have. And if a new trait should arise within the species, then the species includes that trait as one of the many variations.
Species are not homogenous because they are breeds. Breeds are artificially maintained. Dogs are a "hotch-potch" only by human efforts to create and maintain that state. Given the opportunity to interbreed the distinctive breeds would be lost. That is what real species are like.
In truth species are not always homogenous. Consider the peppered moth. The dark form is obviously distinct from the white, but both are the same species. Or another example, the yellow wagtail has a number of distinct variants, which freely interbreed.
And, of course, mutations need not be obvious at all. The genes governing the immune system display a lot of variation - as you may remember there are many distinct alleles in humans - many more than the maximum of four allowed by your Biblical literalism. Yet they are not at all visible to visual inspection.
So, no. it is not even true that all mutations would be rejected by breeders - even breeds have some variations and species have more. But it wouldn't matter if breeders would reject every single one. Species are not artificially defined breeds - they are what they are and if that conflicts with any human ideas of what they "should" be then it is the human ideas that are wrong. The whole idea of "violating the breed" is simply not applicable and to say otherwise is a major error.

This message is a reply to:
 Message 131 by Faith, posted 10-16-2015 5:58 PM Faith has replied

Replies to this message:
 Message 180 by Faith, posted 10-20-2015 2:56 AM PaulK has replied

  
PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


(1)
Message 181 of 259 (771103)
10-20-2015 3:50 AM
Reply to: Message 180 by Faith
10-20-2015 2:56 AM


Re: Adding alleles prevents evolution from occurring
quote:
Of course not. Don't be silly. I'm using the breeding situation as an example of the principle involved. Just as you wouldn't maintain your breed if you allowed alien alleles into it, nature wouldn't be producing the neat clearcut examples of species that it in fact does. You know, lions that ALL look amazingly just like lions and so on.
The same way that wolves ALL look amazingly like wolves, despite having the genetic variation to produce so many different breeds of dog. Seriously Faith, the homogeneity of species is not due to the same lack of variation found in breeds of dog.
quote:
Yeah, if, but in fact it doesn't happen much if at all and if it happened to any appreciable extent it WOULD change the look of a species. Let's not quibble over small degrees of change, just as in breeding you don't want to violate the breed, nature seems to be conservative about hoiding on to her "breeds" too.
They aren't breeds, certainly not in the sense of purebred pedigree dogs. They are species.
And you forget that I am talking about a long term trend of constant genetic diversity (in successful species). Even if you argue that there is a limit on how much genetic diversity a species is "allowed" that limit is not going to decline.
quote:
Doesn't really seem to be the case though, does it? We force the mating of lions and tigers to get "ligers," but in nature it doesn't happen.
I.e. The division between (those) species is not artificially maintained - hardly a counter-example. Where species are willing to interbreed the results are different (e.g. Introduced North American Ruddy Duck, hybridising with European White Headed Ducks. To the point where the latter was threatened with effective extinction)
quote:
Yes, that has to entail some legit form of mutation, but the vast majority of mutations that occur aren't in sex cells anyway, and most are not beneficial either so why keep talking about them as if there was some sort of equation mutation=allele? You don't know that, you aren't offering evidence either, you are just stating the party line as usual.
The fact that there is a group of genes - where diversity is especially important, and where mutation almost certainly contributes to diversity - and yet have no visible affect on appearance is not evidence that genetic variation does not have to produce visible differences in appearance ? I guess you could have said that I was offering proof rather than evidence, but anything else would be ridiculous.
quote:
Oh just make some kind of simple effort to get what I mean instead of blasting away with your silly straw man exaggeration. I meant what I said above: species in the wild DO appear to maintain homogeneity. That's how we know a lion from a kittycat.
A point I answered. So much for "not getting" your argument.
quote:
BUT GO BACK TO THE TITLE OF THIS POST: If you add a bunch of mutations after a species has formed you WILL lose the species. If you add as much as you all WANT to add for fear I'm right that otherwise it's the end of evolution, then you WILL destroy any species that has formed. Please get these things in CONTEXT.
The only way to "lose" a species, other than extinction is for it to merge into another. Adding a few minor variations - to those already existing - is not going to do that. And you cannot sensibly argue that there is a limit on the "allowed" variation within a species below the variation actually existing within real species - but you are arguing just that.
Even those variations that do cause obvious differences in appearance do not "lose" the species. The King cheetah mutation did not "lose" the cheetah.
So IN CONTEXT your claim is clearly and obviously false.

This message is a reply to:
 Message 180 by Faith, posted 10-20-2015 2:56 AM Faith has replied

Replies to this message:
 Message 182 by Faith, posted 10-20-2015 3:54 AM PaulK has replied

  
PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 183 of 259 (771105)
10-20-2015 4:08 AM
Reply to: Message 182 by Faith
10-20-2015 3:54 AM


Re: Adding alleles prevents evolution from occurring
quote:
True, not always, and you are right about wolves. But at the point where a species has just formed or been forming you would not get homogeneity, you'd get scattered phenotypes from the introduction of enough mutations to correct the loss of genetic diversity which is what you are of course trying to do.
As I've said quite often - even in this thread - I expect the majority of the diversity to be added AFTER the new species has formed. So no, I am not arguing that the decline in genetic diversity will be "corrected" at that time. And your "scattered phenotypes" assertion is still wrong for the reasons I have already given.

This message is a reply to:
 Message 182 by Faith, posted 10-20-2015 3:54 AM Faith has replied

Replies to this message:
 Message 184 by Faith, posted 10-20-2015 4:14 AM PaulK has replied

  
PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


(1)
Message 185 of 259 (771107)
10-20-2015 5:18 AM
Reply to: Message 184 by Faith
10-20-2015 4:14 AM


Re: Adding alleles prevents evolution from occurring
If you're going to include all variations then species are "scattered phenotypes", which makes the whole point irrelevant. Unless and until you provide some reason to single out "new" variations (which now apparently includes variations found in other populations of the species!) you don't have a point.

This message is a reply to:
 Message 184 by Faith, posted 10-20-2015 4:14 AM Faith has not replied

  
PaulK
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Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


(4)
Message 186 of 259 (771108)
10-20-2015 6:21 AM


Yellow wagtail: it's complicated
Western Yellow Wagtail
This species' systematics and phylogeny is extremely confusing. Literally dozens of subspecies have been described at one time or another, and some 15-20 are currently considered valid depending on which author reviews them. In addition, the citrine wagtail (M. citreola) forms a cryptic species complex with this bird;[3] both taxa as conventionally delimited are paraphyletic in respect to each other. The populations of the Beringian region are sometimes separated as eastern yellow wagtail (M. tschutschensis).
Or to put it simply, the appearance is so variable that many sub-species have been proposed - and while the "real" number is much lower there's still some disagreement on how many there are. At the same time another, related species is indistinguishable by appearance.
It's complicated.

  
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