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Author Topic:   The End of Evolution By Means of Natural Selection
Dr Adequate
Member
Posts: 16113
Joined: 07-20-2006


Message 30 of 851 (552029)
03-26-2010 12:10 AM
Reply to: Message 7 by Faith
03-25-2010 3:11 PM


Re: Not a simple addition and subtraction problem
If you start with twenty alleles in a population for one gene and one of them becomes crucial for a particular environment and therefore gets selected, either rapidly or slowly depending on the selection pressure, you will lose the other nineteen alleles as the one selected comes to determine this particular trait.
Well, if you had a magic wand that abolishes neutral variation, then I guess that is pretty much what would happen under those particular set of circumstances, if you waited long enough.
And if, on the other hand, you started with one allele and there were twenty different environments into each of which adaptive radiation can take place, such that different versions of that gene would be suited to different environments, then you'd end up with twenty different alleles, if you waited long enough.
What's your point?
Edited by Dr Adequate, : No reason given.

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Dr Adequate
Member
Posts: 16113
Joined: 07-20-2006


(1)
Message 32 of 851 (552032)
03-26-2010 2:05 AM
Reply to: Message 1 by Faith
03-25-2010 1:07 PM


Then if you think mutation can save the day, all that happens is that the mutated allele gradually eliminates all the other alleles, once again eliminating genetic diversity.
This is only what happens to one gene of course, but the trend is inexorable.
By looking at just one gene, and by considering the moment of fixation as an end state instead of just more of the middle of the process, you've ignored equilibrium heterozygosity.
You may get a new trait but you'll always get it at the expense of all the other genetic possibilities ...
Well this is where your argument really breaks down, isn't it? Because the fixation of an allele in one population doesn't magically cause its fixation in another. So long as there's room for adaptive radiation, the diversity will in fact increase. Your argument applies only when the ecology has reached such a climax of diversity that one species can only be replaced by one other species, instead of diverging into two.
The production of additional net diversity has, I suppose, to stop at some point --- just as someone climbing Mount Everest must eventually reach a point where he can't get any higher. But this is not a valid argument that it is impossible to climb up Mount Everest, only an argument that it is impossible to climb up when you're on the summit.

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Dr Adequate
Member
Posts: 16113
Joined: 07-20-2006


Message 34 of 851 (552034)
03-26-2010 2:10 AM
Reply to: Message 31 by Faith
03-26-2010 2:01 AM


Re: Not a simple addition and subtraction problem
This isn't meant to be a complete picture of how evolution works ...
Good, 'cos it isn't.
... but an example pared down to its essentials to make the point I want to make.
And if you gave the ostrich as your sole example of a bird, "pared down to its essentials", then this would assist you to make the point that it is impossible for birds to fly.
It would not, however, provide you with a valid form of argument.

This message is a reply to:
 Message 31 by Faith, posted 03-26-2010 2:01 AM Faith has replied

Replies to this message:
 Message 35 by Faith, posted 03-26-2010 2:13 AM Dr Adequate has replied

  
Dr Adequate
Member
Posts: 16113
Joined: 07-20-2006


Message 36 of 851 (552036)
03-26-2010 2:16 AM
Reply to: Message 33 by Faith
03-26-2010 2:09 AM


Re: Dog breeding as per usual.
That is, if you want to maximize certain characteristics of your dog, what you have to do is make sure it can't breed with dogs that have different characteristics. It's a process of eliminating what you don't want.
* sigh *
But this process may reduce the diversity in each breed of dog but increases the number of breeds of dog, thus producing a net increase in diversity.
The net result is that breeding by humans has quite visibly and obviously increased the diversity of the dog/wolf species.

This message is a reply to:
 Message 33 by Faith, posted 03-26-2010 2:09 AM Faith has replied

Replies to this message:
 Message 51 by nwr, posted 03-26-2010 8:44 AM Dr Adequate has replied
 Message 102 by Faith, posted 03-28-2010 6:47 AM Dr Adequate has replied

  
Dr Adequate
Member
Posts: 16113
Joined: 07-20-2006


Message 37 of 851 (552037)
03-26-2010 2:17 AM
Reply to: Message 35 by Faith
03-26-2010 2:13 AM


Re: Not a simple addition and subtraction problem
My my my, Dr. A with his flat assertive pronouncements as if from on high, how very scientific of you.
If you are really unable to find a single error in anything that I've written, you could convey this best by agreement followed by silence.

This message is a reply to:
 Message 35 by Faith, posted 03-26-2010 2:13 AM Faith has replied

Replies to this message:
 Message 39 by Faith, posted 03-26-2010 2:38 AM Dr Adequate has replied

  
Dr Adequate
Member
Posts: 16113
Joined: 07-20-2006


Message 47 of 851 (552057)
03-26-2010 7:57 AM
Reply to: Message 39 by Faith
03-26-2010 2:38 AM


Re: Not a simple addition and subtraction problem
I haven't got down to your posts, Dr. A, but I will, I will. Patience.
Well, good, I look forward to it.
But what I find rather odd is that before you've actually gotten round to discussing one single thing that I've actually said, you've put up a snide remark pro tem.
It is you, I think, who needs to learn the lesson of "patience". If I'm wrong, then you can analyze my wrongness at your leisure. I'm not going to rush you. If, on the other hand, I'm not wrong, then you shouldn't have rushed to write a post contemning me personally when my whole offense was to write something so correct that at present you are utterly unable to dispute it.

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Dr Adequate
Member
Posts: 16113
Joined: 07-20-2006


Message 49 of 851 (552060)
03-26-2010 8:07 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.
* sighs again *
In the case that you bring up, the action of evolution may well have diminished the variation within species, but it also produced more species. Thus increasing genetic diversity.
The interesting thing about what you're doing is that you appear to be committing the fallacy known as "moving the goalposts" inside your head, but without ever doing so explicitly. In your line of argument, as soon as radiative adaptation starts happening, you move the goalposts and it becomes two separate examples of evolution, both of which are conservative.
Edited by Dr Adequate, : No reason given.

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 109 by Faith, posted 03-28-2010 7:46 AM Dr Adequate has replied

  
Dr Adequate
Member
Posts: 16113
Joined: 07-20-2006


(1)
Message 53 of 851 (552073)
03-26-2010 10:12 AM
Reply to: Message 51 by nwr
03-26-2010 8:44 AM


Re: Dog breeding as per usual.
She is arguing that as the biosphere branches out, producing more variety, eventually it will reach dead ends where no further evolution is possible beyond those dead end points.
Well, this is why I wrote in post #32:
me writes:
The production of additional net diversity has, I suppose, to stop at some point --- just as someone climbing Mount Everest must eventually reach a point where he can't get any higher. But this is not a valid argument that it is impossible to climb up Mount Everest, only an argument that it is impossible to climb up when you're on the summit.
Now, in case you've never met Faith before, then you should know that Faith is a creationist. She is not trying to argue that futher evolution is impossible now (which would merely be silly) but that evolution was impossible in the first place (which is downright crazy).
In effect, you are trying to twist her words so that they mean something nearly reasonable, whereas the thing that she's actually trying to say is gormlessly stupid.

This message is a reply to:
 Message 51 by nwr, posted 03-26-2010 8:44 AM nwr has replied

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Dr Adequate
Member
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

  
Dr Adequate
Member
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

  
Dr Adequate
Member
Posts: 16113
Joined: 07-20-2006


(1)
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

  
Dr Adequate
Member
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.

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 Message 72 by Faith, posted 03-27-2010 4:12 AM Faith has not replied

  
Dr Adequate
Member
Posts: 16113
Joined: 07-20-2006


Message 96 of 851 (552290)
03-28-2010 1:52 AM
Reply to: Message 78 by Faith
03-27-2010 1:52 PM


Speciation
Having read your screed, I think I see the essence of your mistake.
Let's try to formalize our language by labeling genes with letters and alleles with numbers, so that, for example, c1 and c2 would be two alternative alleles of gene c. OK so far?
Now, you seem to be imagining the origin of species by a whittling away of alleles.
For example, imagine a species which has two alleles for every gene, and twenty-six genes (twenty-six because that's how many letters of the alphabet I have to work with). So it has alleles a1, a2, b1, b2 ... z1, z2.
Now, you seem, stop me if I'm wrong, to be imagining speciation happening by a process which reduces the alleles, so that a new species can be produced by a series of selection events which leaves the daughter population with only the alleles a1, b1 ... z1.
But this would not actually be speciation. For a member of the daughter population would be indistinguishable from a member of the parent population such as might be produced by recombination. So we might be able to find a member of the parent population which was genetically indistinguishable from a member of the daughter population. So how could we say that two identical organisms were members of different species?
(In Noah's flood, the reduction of giraffes to two would have severely depleted the genetic diversity of giraffes, but this would not mean that the two giraffes selected by Noah were somehow non-giraffes.)
So when you write:
You simply do NOT get a new phenotype, a new variation, a new breed of dog, without losing genetic options.
... then this is true, but it's only half the story. Because you need some production of new alleles to displace the old ones in the daughter population, otherwise what you are seeing is not speciation. There must be an increase as well as a reduction, otherwise you haven't produced a new species.
Your confusion is most evident when you write:
The entrance of new alleles is a BAD thing for domestic breeding, you don't want it.
Now, that's a bad thing if your aim is to preserve the purity of a breed. But it's exactly what you need if you want to produce a new breed. If no mutation had arisen that made dogs have webbed feet, then no-one could have produced web-footed breeds of dogs.
And in general, if dogs had been produced simply by selecting from the genetic material already available in wolves, then each dog would be indistinguishable from something which wolves might have produced themselves by sexual recombination. You would have to suppose that it was possible for two feral wolves to have sex and, by a lucky chance, produce a chihuahua or a dalmatian or an Old English Sheepdog because the pre-existing wolf alleles had happened to get arranged in just the right combination.
Again, you write:
So you are throwing new mutations at these genetically depleted new species, not recognizing that the very existence of the new species requires the genetic depletion and if you add mutations you only destroy the species ...
Italics mine. Yes, enough mutations "destroy the species". And therefore, by definition, create a new one. That's what speciation means --- that the new kind of organism is a different species from the one from which it is descended.
---
You have made a number of minor errors in genetics and the theory of evolution, but I think that this is where your fundamental error lies.
Edited by Dr Adequate, : No reason given.
Edited by Dr Adequate, : No reason given.
Edited by Dr Adequate, : No reason given.

This message is a reply to:
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Dr Adequate
Member
Posts: 16113
Joined: 07-20-2006


Message 104 of 851 (552317)
03-28-2010 7:05 AM
Reply to: Message 102 by Faith
03-28-2010 6:47 AM


Re: Dog breeding as per usual.
This isn't GENETIC diversity you're talking about. You're talking about the proliferation of varieties or breeds.
A distinction without a difference. The reason that poodles, greyhounds, bulldogs and so forth look more diverse than wolves is because of an underlying genetic diversity. How else?
But EACH of the breeds has been able to form BECAUSE it has its own reduced complement of alleles compared to the parent population.
See my last post.

This message is a reply to:
 Message 102 by Faith, posted 03-28-2010 6:47 AM Faith has not replied

  
Dr Adequate
Member
Posts: 16113
Joined: 07-20-2006


Message 108 of 851 (552322)
03-28-2010 7:43 AM
Reply to: Message 106 by Faith
03-28-2010 7:19 AM


Re:
I assume enormous genetic diversity in the passengers on the ark ...
You do? The animals went in two by two, hurrah, hurrah. Do you suppose that the two wolves contained within themselves sufficient genetic diversity to produce every breed of dog --- so that when they bred, sexual recombination might have at once produced a litter consisting of a greyhound, a chihuahua, a bulldog, a poodle, a Pomerian, and an Old English Sheepdog?

This message is a reply to:
 Message 106 by Faith, posted 03-28-2010 7:19 AM Faith has replied

Replies to this message:
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