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Author Topic:   Wright et al. on the Process of Mutation
Kaichos Man
Member (Idle past 3352 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 189 of 296 (643821)
12-12-2011 6:43 AM
Reply to: Message 183 by Percy
10-14-2011 4:54 PM


Long time no contradict
Hi Percy.

This is off-topic, but you lead me here, so mea non culpa.

thank God two wrongs make a right. Oh, wait a minute, they don't.

No, but three can. You are meant to turn right, in stead you turn left. Three times. You're going right. Okay, that's frivolous but I'm just warming up.

I don't believe man was created by pure chance. I believe all life on Earth came about through a lengthy process of mutation, remixing and recombining of variation, and natural selection.

So although mutation, remixing and recombination are clearly random, natural selection isn't?

...natural selection is not random. It isn't directed, there's no goal, but it is certainly not random.

But surely the conditions bringing about selection are random. Heat, cold, wet, dry, plentiful food, little food, intense competition, little competition, intense predation, little predation- the list is endless.

If the conditions deciding selection are random, how can selection itself not be random?

Are you seriously suggesting that a random cause can have a non-random effect?

And of course, the longer we make that list of random causes, the more obvious it becomes that selective fitness can best be described as ...luck.

Which, at the risk of annoying you, brings us back to the position of our old mate Kimura.


"When man loses God, he does not believe in nothing. He believes in anything" G.K. Chesterton

This message is a reply to:
 Message 183 by Percy, posted 10-14-2011 4:54 PM Percy has responded

Replies to this message:
 Message 190 by Percy, posted 12-12-2011 7:00 AM Kaichos Man has not yet responded
 Message 191 by Wounded King, posted 12-12-2011 9:59 AM Kaichos Man has responded
 Message 192 by Dr Adequate, posted 12-12-2011 10:33 AM Kaichos Man has not yet responded
 Message 193 by Dr Adequate, posted 12-12-2011 11:59 AM Kaichos Man has not yet responded
 Message 194 by Taq, posted 12-12-2011 12:06 PM Kaichos Man has responded

  
Kaichos Man
Member (Idle past 3352 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 196 of 296 (643931)
12-13-2011 7:33 AM
Reply to: Message 194 by Taq
12-12-2011 12:06 PM


Re: Long time no contradict
You mean the guy who described the random nature of neutral mutations compared to the non-random nature of mutations under selection?

That's right. The same guy who you and the Good Doctor think is on your side, but Dobzhansky was under no such illusion. The following from a BBC transcript- I can source it if you like:

Dobzhansky: It took a century to show that [objections to Darwinism] are devoid of foundation. But now Dr. Kimura and his followers claim evolution to be due to changes which are neither useful nor harmful to their possessors. They are simply neutral and are established merely by chance. If that were so, evolution would have hardly any meaning, and would not be going anywhere in particular. All that we know—all that we observe both in nature and in the laboratory—seems, I believe, to contradict this contention. This is not simply a quibble among specialists. To a man looking for the meaning of his existence, evolution by natural selection makes sense.

Interesting little Freudian slip in that last sentence. "Looking for meaning"? I thought the central tenet of evolution is that there is no purpose, and therefore no meaning.


"When man loses God, he does not believe in nothing. He believes in anything" G.K. Chesterton

This message is a reply to:
 Message 194 by Taq, posted 12-12-2011 12:06 PM Taq has not yet responded

Replies to this message:
 Message 201 by Dr Adequate, posted 12-14-2011 12:30 AM Kaichos Man has responded

  
Kaichos Man
Member (Idle past 3352 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 197 of 296 (643934)
12-13-2011 7:50 AM
Reply to: Message 191 by Wounded King
12-12-2011 9:59 AM


Re: Long time no contradict
To my suggestion that luck might be the deciding factor in selection, in line with kimura's beliefs, you wrote:

It so totally doesn't, at least not in relation to any position that Kimura actually held.

"I feel very lucky that this revolution occurred just at the time when my theoretical work was ready for it. I was therefore able to publish the first version of my neutral theory of molecular evolution just twenty years ago... . After the expression, ``Survival of the Fittest,'' which epitomizes the Darwinian theory of natural selection, I have proposed ``Survival of the Luckiest'' as a phrase that best characterizes my Neutral Theory. (Kimura, 1990a)"


"When man loses God, he does not believe in nothing. He believes in anything" G.K. Chesterton

This message is a reply to:
 Message 191 by Wounded King, posted 12-12-2011 9:59 AM Wounded King has responded

Replies to this message:
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 Message 199 by Wounded King, posted 12-13-2011 8:21 AM Kaichos Man has responded
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Kaichos Man
Member (Idle past 3352 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 202 of 296 (644005)
12-14-2011 4:01 AM
Reply to: Message 201 by Dr Adequate
12-14-2011 12:30 AM


Re: Long time no contradict
Whereas I associate the doctrine that evolution would render existence meaningless with the bunch of religious crackpots who actually promulgate it.

Indeed Dotore?

Then kindly explain how a random, directionless and purposeless process can give rise to a "meaningful" existence. Perhaps you would like to start with a non-vital human morality like honesty? Then you can go on with universal human qualities like worship, guilt, love, art, humour, etc.

We're waiting.


"When man loses God, he does not believe in nothing. He believes in anything" G.K. Chesterton

This message is a reply to:
 Message 201 by Dr Adequate, posted 12-14-2011 12:30 AM Dr Adequate has responded

Replies to this message:
 Message 203 by Dr Adequate, posted 12-14-2011 4:28 AM Kaichos Man has responded
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Kaichos Man
Member (Idle past 3352 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 205 of 296 (644008)
12-14-2011 4:34 AM
Reply to: Message 199 by Wounded King
12-13-2011 8:21 AM


Re: Kimura redux
all you have shown is that Kimura believed chance was important in the generation of the genetic variation that we see in populations. You haven't shown that he thought it had anything to do with selection.

Well, let's consult the little Japanes master himself on that, WK:

"Finally, I would like to discuss briefly the problem How
can we understand evolution at two levels-that is, molecular
and phenotypic-in a unified way? It is generally believed
that, in contrast to the neutralist view of molecular evolution,
evolutionary changes at the phenotypic level are almost
exclusively adaptive and caused by Darwinian positive selection.
However, I think that even at the phenotypic level,
there must be many changes that are so nearly neutral that
random drift plays a significant role, particularly with respect
to "quantitative characters."

So while changes at the molecular level are neutral, changes at the phenotype level are "almost exclusively adaptive". Kimura then goes on to disagree with this "However...there must be many changes that are so nearly neutral that random drift plays a significant role".

I believe Kimura is working his way around the elephant in the room here. How can the genotype and the phenotype evolve by different methods? They can't. Example:

Organism X gets a mutation. The mutation proves beneficial. Over time, all non-mutants in the population die out, and the mutation become fixed. The phenotype has evolved through selection. What about the genotype? That must have evolved through selection, too, and Kimura must be wrong.

He wasn't, of course. But then he knew that the only mutations that endure are non-deleterious, i.e. they don't damage important DNA. They don't lead to evolution either, but that's the neo-Darwinist's problem.

So the genotype evolves by neutral mutations, while its physical expression, the phenotype, advances through selection. Poppycock.

Kimura knew this. That's why he wrote:

"Advantageous mutations may occur, but the neutral theory
assumes that they are so rare that they may be neglected in
our quantitative consideration."

Kimura's concession that selection evolves the phenotype was a logical non-sequiture designed to placate anxious neo-Darwinists. He knew it made no sense. But it kept them off his back.


"When man loses God, he does not believe in nothing. He believes in anything" G.K. Chesterton

This message is a reply to:
 Message 199 by Wounded King, posted 12-13-2011 8:21 AM Wounded King has not yet responded

Replies to this message:
 Message 206 by Dr Adequate, posted 12-14-2011 4:38 AM Kaichos Man has responded

  
Kaichos Man
Member (Idle past 3352 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 207 of 296 (644010)
12-14-2011 6:42 AM
Reply to: Message 199 by Wounded King
12-13-2011 8:21 AM


Re: Kimura redux
all you have shown is that Kimura believed chance was important in the generation of the genetic variation that we see in populations. You haven't shown that he thought it had anything to do with selection.

Well, let's consult the little Japanes master himself on that, WK:

"Finally, I would like to discuss briefly the problem How
can we understand evolution at two levels-that is, molecular
and phenotypic-in a unified way? It is generally believed
that, in contrast to the neutralist view of molecular evolution,
evolutionary changes at the phenotypic level are almost
exclusively adaptive and caused by Darwinian positive selection.
However, I think that even at the phenotypic level,
there must be many changes that are so nearly neutral that
random drift plays a significant role, particularly with respect
to "quantitative characters."

So while changes at the molecular level are neutral, changes at the phenotype level are "almost exclusively adaptive". Kimura then goes on to disagree with this "However...there must be many changes that are so nearly neutral that random drift plays a significant role".

I believe Kimura is working his way around the elephant in the room here. How can the genotype and the phenotype evolve by different methods? They can't. Example:

Organism X gets a mutation. The mutation proves beneficial. Over time, all non-mutants in the population die out, and the mutation become fixed. The phenotype has evolved through selection. What about the genotype? That must have evolved through selection, too, and Kimura must be wrong.

He wasn't, of course. But then he knew that the only mutations that endure are non-deleterious, i.e. they don't damage important DNA. They don't lead to evolution either, but that's the neo-Darwinist's problem.

So the genotype evolves by neutral mutations, while its physical expression, the phenotype, advances through selection. Poppycock.

Kimura knew this. That's why he wrote:

"Advantageous mutations may occur, but the neutral theory
assumes that they are so rare that they may be neglected in
our quantitative consideration."

Kimura's concession that selection evolves the phenotype was a logical non-sequiteur designed to placate anxious neo-Darwinists. He knew it made no sense. But it kept them off his back.


"When man loses God, he does not believe in nothing. He believes in anything" G.K. Chesterton

This message is a reply to:
 Message 199 by Wounded King, posted 12-13-2011 8:21 AM Wounded King has not yet responded

Replies to this message:
 Message 208 by Kaichos Man, posted 12-14-2011 6:44 AM Kaichos Man has not yet responded

  
Kaichos Man
Member (Idle past 3352 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 208 of 296 (644011)
12-14-2011 6:44 AM
Reply to: Message 207 by Kaichos Man
12-14-2011 6:42 AM


Re: Kimura redux
Sorry, my computer was telling me I hadn't posted this.

This message is a reply to:
 Message 207 by Kaichos Man, posted 12-14-2011 6:42 AM Kaichos Man has not yet responded

Replies to this message:
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Kaichos Man
Member (Idle past 3352 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 209 of 296 (644014)
12-14-2011 7:00 AM
Reply to: Message 206 by Dr Adequate
12-14-2011 4:38 AM


Re: Kimura redux
... by accusing Kimura of being a deliberate and calculating liar?

I don't think throwing a drowning man a straw is lying. It's just placating those who believe the man isn't really drowning.

This from Motoo:

"More than a decade and a half ago, in collaboration with Ohta, I enumerated five principles that govern molecular evolution, one of which states that functionally less important molecules or parts of a molecule evolve (in terms of mutant substitutions) faster than more important ones."

Even here Kimura is throwing the neo-Darwinists a bone. He could equally have said that functionally less important parts of a molecule evolve, while important ones don't. After all, this is precisely what his research shows. Speed has nothing to do with it.

"When this principle was proposed, accompanied by its neutralist explanation, much opposition was voiced by the neo-Darwinian establishment"

You boys got your knickers in a twist.

"... but I am glad to note that it has become a part of common knowledge among molecular biologists

I was right. Suck it up.

Hey, you can still pretend that selection somehow -magically- evolves the phenotype while leaving the genotype untouched. Little cognitive dissonance. It's not so hard.


"When man loses God, he does not believe in nothing. He believes in anything" G.K. Chesterton

This message is a reply to:
 Message 206 by Dr Adequate, posted 12-14-2011 4:38 AM Dr Adequate has responded

Replies to this message:
 Message 212 by Dr Adequate, posted 12-14-2011 7:05 AM Kaichos Man has not yet responded
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Kaichos Man
Member (Idle past 3352 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 211 of 296 (644016)
12-14-2011 7:05 AM
Reply to: Message 203 by Dr Adequate
12-14-2011 4:28 AM


Re: Long time no contradict
For example, by producing human beings, who have a meaningful existence.

Could you define "meaningful" in evolutionary terms, Doc?


"When man loses God, he does not believe in nothing. He believes in anything" G.K. Chesterton

This message is a reply to:
 Message 203 by Dr Adequate, posted 12-14-2011 4:28 AM Dr Adequate has not yet responded

  
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