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Author Topic:   What exactly is natural selection and precisely where does it occur?
Fosdick 
Suspended Member (Idle past 5500 days)
Posts: 1793
From: Upper Slobovia
Joined: 12-11-2006


Message 286 of 303 (391553)
03-25-2007 8:13 PM
Reply to: Message 284 by Modulous
03-25-2007 4:29 PM


Re: Another paradox from individual selection
Modulous writes:
The big question is of individual and gene view selection. Some 'Neville Chamberlains' have proposed a compromise, that both views are valid depending on the situation.
If I am a 'Neville Chamberlain' then who is a 'Hitler'? Wait, wait, let me guess.
But more to the point:
I think the answer to where exactly does natural selection occur is at the gene level. Not the individual, the deme, the species or any other place in the heirarchy. There may be selection occurring, but it is not natural selection.
I mostly have to agree with your argument.
”HM

This message is a reply to:
 Message 284 by Modulous, posted 03-25-2007 4:29 PM Modulous has not replied

crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 287 of 303 (391554)
03-25-2007 8:36 PM
Reply to: Message 285 by Fosdick
03-25-2007 7:43 PM


Re: Hoot Mon's not entirely unreasonable position:
I've been held up for ridicule, called names like "schnook,"
You poor dear!

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 Message 285 by Fosdick, posted 03-25-2007 7:43 PM Fosdick has not replied

Quetzal
Member (Idle past 5872 days)
Posts: 3228
Joined: 01-09-2002


Message 288 of 303 (391756)
03-27-2007 9:43 AM


Summation
Although I'm not entirely sure of the purpose it would serve, since Mod took the time to summarize his position, I suppose (in the absence of anyone else interested in so doing) I better summarize the opposing viewpoint. Some of the points below have been discussed in this thread, others may not have been directly addressed.
1. With the possible - albeit poorly understood and hence disputable - exception of the phenomenon known as segregation distortion (aka, meiotic drive), there is no known selection pressure that operates directly on a gene, suite of genes, or even genotype. Rather, selection affects the entire organism through either enhancing or restricting individual survival (the carrier of the gene), or over the longer term, the reproductive success or rate of the individual organism. Whereas a gene or polygene can be said to be "promoted" by selection if it increases in frequency in subsequent generations, it is actually the phenotypical expression of the gene that is affected. Since phenotype is ineluctably and directly tied to the interaction of the whole organism and its environment, attempting to understand this interaction in the context of genes (rather than individuals) tends to distort and/or add an unnecessary level of abstraction when discussing natural selection itself.
2. Genecentrism is in essence an evolutionary metaphor. As such, the viewpoint is not designed to - and thus cannot - make a distinction between selection itself and the evolutionary response to selection. Thus genecentrism is unable to address a whole gamut of interesting questions concerning the ecological effects on individuals, populations, etc, of environmental factors in a single (or a limited number of) generations. These questions are, in fact, dismissed as "uninteresting" in an evolutionary context. I submit, however, that for numerous disciplines such questions are not only not "uninteresting", but actually key to our understanding of nature and natural history.
3. Genecentrism dismisses most concepts of "fitness" as an organismal measure. At best, it allows only discussion of the relative fitness of particular alleles, and ignores the concept of absolute fitness. However, even here, there is really no effective way for genecentrists to measure such allelic fitness without implicitly or explicitly referring to the effect of those alleles on the individual which carries them - because, after all, it is the individual which passes those alleles on to subsequent generations. In other words, again we are adding an unnecessary level of abstraction to the discussion. Outside of the discipline of population genetics, this abstraction serves no function other than to obscure what occurs in nature.
4. There are a number of biological sciences where it simply makes no sense to insist on a genes-eye-view, primarily because these disciplines are more holistic in nature. The one that immediately springs to my mind is (of course) ecology. With the exception of those genetically-related elements such as certain aspects of population dynamics (for instance, inbreeding depression) and extinction or extinction threat (for instance, the phenomenon of extinction vortex), the insistence of the proponents of genecentrism that theirs is the only "accurate" viewpoint would perforce render much of ecology unworkable - or perhaps only "uninteresting" - because ecology is concerned primarily with macroscale (vice gene-level microscale) interactions. Since ecology is arguably the science most concerned with natural selection (writ large) in the wild, the fact that genecentrism is not particularly useful - and in fact may be unusable in many contexts - for that science should give the genecentrists pause.
5. And finally, on a very personal note, although I am aware there are many scientists - especially evolutionary biologists - who are very capable of discussing genecentrism in technical terms, there seems to be a nearly inescapable tendency even among themselves to use highly anthropomorphic language. Phrases like "selfish gene", "cooperative genes", and "A fit individual is one which works towards ensuring its alleles replicate." do nothing for understanding the actual biology of what is occurring. In fact, I submit that the terminology used in these cases is not only "inaccurate", but misleading, ambiguous, and obfuscatory.
For these reasons, and others, I feel that the genecentric viewpoint - although having a place in evolution - is NOT the best and most accurate way of either looking at or describing natural selection.
And may Darwin have mercy on us for wasting 288 posts on this subject.

Replies to this message:
 Message 289 by Fosdick, posted 03-27-2007 1:11 PM Quetzal has not replied

Fosdick 
Suspended Member (Idle past 5500 days)
Posts: 1793
From: Upper Slobovia
Joined: 12-11-2006


Message 289 of 303 (391797)
03-27-2007 1:11 PM
Reply to: Message 288 by Quetzal
03-27-2007 9:43 AM


Re: Summation
Quetzal wrote: For these reasons, and others, I feel that the gene-centric viewpoint - although having a place in evolution - is NOT the best and most accurate way of either looking at or describing natural selection.
And may Darwin have mercy on us for wasting 288 posts on this subject.
Those 288 posts were not wasted on me. Many good points were made on either side of the natural-selection argument. In general, the Quetzal v. Mod arguments were for us a fair representation of Gould v. Dawkins. Gould saw natural selection operating on the individual/group level of biological organization. Dawkins sees it instead as working at the gene/kin level. I think a great deal of clarity comes out of arguing these opposing views.
As a scientist, I feel committed to viewing everything natural in terms of principles. If natural selection means anything at all, it must work according to biological principles, either known or unknown. So, as we argue the finer points of NS, we must necessarily attack each other’s principles, or lack thereof, to find the more durable explanation. Both Quetzal and Modulous express themselves so well that it is clear to me we have only one conclusion: Natural selection still shows disputed evidence of being at the scene of an evolutionary crime, because we can't agree on the scene.
I think our only hope for agreeing on the meaning of natural selection, and agreeing on how evolution via natural selection works, is to focus on the specific definition of NS: Differential reproductive success amongst individuals of a population. Natural selection, in and of itself, does not mean sexual selection, random genetic drift, gene flows, or mutations; it means only that differential reproductive success amongst individuals of a population has taken place.
Looking at NS as an effect, one might argue that sexual selection, random genetic drift, gene flows, and mutations could play their causal roles in NS. Or they might work independently to cause a microevolutionary event; NS may not always play a role. I would agree. But the bottom line, in my best estimation, is that NS associates causally with the redistribution of allele frequencies, because differential reproductive success will statistically do that, but it is only one of five known causes of allele-frequency redistribution. Therefore NS may also be an effect, suggesting a causal linkage to a microevolutionary event would need to be understood. To focus on the deeper meaning of NS, deeper than just “individual organisms being selected,” we have to focus on the evolution of allele frequencies. Genes, then, are where the NS action is. This seems to be obvious, at least to me, now in the modern times of molecular biology.
”HM

This message is a reply to:
 Message 288 by Quetzal, posted 03-27-2007 9:43 AM Quetzal has not replied

Replies to this message:
 Message 290 by Jazzns, posted 03-27-2007 1:48 PM Fosdick has replied
 Message 291 by crashfrog, posted 03-27-2007 3:31 PM Fosdick has replied

Jazzns
Member (Idle past 3912 days)
Posts: 2657
From: A Better America
Joined: 07-23-2004


Message 290 of 303 (391803)
03-27-2007 1:48 PM
Reply to: Message 289 by Fosdick
03-27-2007 1:11 PM


Re: Summation
I have a question:
the specific definition of NS: Differential reproductive success amongst individuals of a population. Natural selection, in and of itself, does not mean sexual selection,...
Under what conditions do you ever concieve that sexual selection would NOT produce differential reproductive success? That would be the only case where you couldn't call sexual selection a type of natural selection right? Where mate preference is occurring yet everyone is still equally successful in reproduction. When would that EVER actually occur? Does that not directly contradict that concept of "preference"?

Of course, biblical creationists are committed to belief in God's written Word, the Bible, which forbids bearing false witness; --AIG (lest they forget)

This message is a reply to:
 Message 289 by Fosdick, posted 03-27-2007 1:11 PM Fosdick has replied

Replies to this message:
 Message 294 by Fosdick, posted 03-27-2007 4:51 PM Jazzns has not replied

crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 291 of 303 (391813)
03-27-2007 3:31 PM
Reply to: Message 289 by Fosdick
03-27-2007 1:11 PM


Re: Summation
Congratulations, everybody!
Looking at NS as an effect, one might argue that sexual selection, random genetic drift, gene flows, and mutations could play their causal roles in NS. Or they might work independently to cause a microevolutionary event; NS may not always play a role. I would agree. But the bottom line, in my best estimation, is that NS associates causally with the redistribution of allele frequencies, because differential reproductive success will statistically do that, but it is only one of five known causes of allele-frequency redistribution. Therefore NS may also be an effect, suggesting a causal linkage to a microevolutionary event would need to be understood. To focus on the deeper meaning of NS, deeper than just “individual organisms being selected,” we have to focus on the evolution of allele frequencies. Genes, then, are where the NS action is. This seems to be obvious, at least to me, now in the modern times of molecular biology.
288 posts did absolutely nothing to stem HM's tide of pseudoscientific nonsense.

This message is a reply to:
 Message 289 by Fosdick, posted 03-27-2007 1:11 PM Fosdick has replied

Replies to this message:
 Message 293 by Fosdick, posted 03-27-2007 4:37 PM crashfrog has replied

Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 292 of 303 (391828)
03-27-2007 4:33 PM


My Summation
This thread represents a profound failure on the part of the participating evolutionists (I do not except myself), because after nearly 300 messages in a thread whose purpose was to clearly define natural selection for Hoot Mon, his conclusion is that we're not exactly sure what it is and that it requires deeper study.
--Percy

Replies to this message:
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Fosdick 
Suspended Member (Idle past 5500 days)
Posts: 1793
From: Upper Slobovia
Joined: 12-11-2006


Message 293 of 303 (391829)
03-27-2007 4:37 PM
Reply to: Message 291 by crashfrog
03-27-2007 3:31 PM


Re: Summation
Congratulations, every body!
288 posts did absolutely nothing to stem HM's tide of pseudoscientific nonsense.
And congratulations, froggie. That's the most substance I've seen in one of your posts since you reported finding E. Coli on your lawn.
”HM

This message is a reply to:
 Message 291 by crashfrog, posted 03-27-2007 3:31 PM crashfrog has replied

Replies to this message:
 Message 296 by crashfrog, posted 03-27-2007 5:07 PM Fosdick has replied

Fosdick 
Suspended Member (Idle past 5500 days)
Posts: 1793
From: Upper Slobovia
Joined: 12-11-2006


Message 294 of 303 (391834)
03-27-2007 4:51 PM
Reply to: Message 290 by Jazzns
03-27-2007 1:48 PM


Re: Summation
Jazzns asked:
Under what conditions do you ever concieve that sexual selection would NOT produce differential reproductive success?
Non-random mating certaily would affect natural selection under most conditions, but not all of them. Why would every case of nonrandom mating necessarily cause differential reproductive success in a population if all individuals happen reproduced equally? Nonrandom mating does NOT automatically mean natural selection.
”HM

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 Message 290 by Jazzns, posted 03-27-2007 1:48 PM Jazzns has not replied

Fosdick 
Suspended Member (Idle past 5500 days)
Posts: 1793
From: Upper Slobovia
Joined: 12-11-2006


Message 295 of 303 (391835)
03-27-2007 4:55 PM
Reply to: Message 292 by Percy
03-27-2007 4:33 PM


Re: My Summation
Percy exhaust:
This thread represents a profound failure on the part of the participating evolutionists (I do not except myself), because after nearly 300 messages in a thread whose purpose was to clearly define natural selection for Hoot Mon, his conclusion is that we're not exactly sure what it is and that it requires deeper study.
Maybe some of us are most interested in a deeper meaning of natural selection than Wikipedia can provide.
”HM

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 Message 292 by Percy, posted 03-27-2007 4:33 PM Percy has not replied

crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 296 of 303 (391837)
03-27-2007 5:07 PM
Reply to: Message 293 by Fosdick
03-27-2007 4:37 PM


Re: Summation
That's the most substance I've seen in one of your posts since you reported finding E. Coli on your lawn.
I don't recall reporting that, but I don't believe I would be surprised to find E. coli out on my lawn, or anyone else's.
I suspect it's just that, in your truly all-encompassing ignorance, you don't know what it means when a microbiologist talks about a "lawn."

This message is a reply to:
 Message 293 by Fosdick, posted 03-27-2007 4:37 PM Fosdick has replied

Replies to this message:
 Message 297 by Fosdick, posted 03-27-2007 7:16 PM crashfrog has replied

Fosdick 
Suspended Member (Idle past 5500 days)
Posts: 1793
From: Upper Slobovia
Joined: 12-11-2006


Message 297 of 303 (391860)
03-27-2007 7:16 PM
Reply to: Message 296 by crashfrog
03-27-2007 5:07 PM


Re: Summation
I don't recall reporting that, but I don't believe I would be surprised to find E. coli out on my lawn, or anyone else's. I suspect it's just that, in your truly all-encompassing ignorance, you don't know what it means when a microbiologist talks about a "lawn."
Are you a microbiologist? I suspect you are not, since you didn't even know about E. coli conjugation.
”HM

This message is a reply to:
 Message 296 by crashfrog, posted 03-27-2007 5:07 PM crashfrog has replied

Replies to this message:
 Message 298 by crashfrog, posted 03-27-2007 7:31 PM Fosdick has replied

crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 298 of 303 (391861)
03-27-2007 7:31 PM
Reply to: Message 297 by Fosdick
03-27-2007 7:16 PM


Re: Summation
Are you a microbiologist?
Are you a "scientist" like you claimed to be? I'd like to read some of your published work, if so. (Do you save your nonsense just for us, or inflict it on the journals, too?) Can you pop me a few bibliographies? Email would be fine if you don't want to break anonymity.

This message is a reply to:
 Message 297 by Fosdick, posted 03-27-2007 7:16 PM Fosdick has replied

Replies to this message:
 Message 299 by Fosdick, posted 03-28-2007 9:56 AM crashfrog has replied

Fosdick 
Suspended Member (Idle past 5500 days)
Posts: 1793
From: Upper Slobovia
Joined: 12-11-2006


Message 299 of 303 (391965)
03-28-2007 9:56 AM
Reply to: Message 298 by crashfrog
03-27-2007 7:31 PM


Re: Summation
crashfrog wrote:
Are you a "scientist" like you claimed to be? I'd like to read some of your published work, if so. (Do you save your nonsense just for us, or inflict it on the journals, too?) Can you pop me a few bibliographies? Email would be fine if you don't want to break anonymity.
I did what crashfrog requested of me by way of email. I did it in the spirit of friendship and with good intentions. Bad idea! Here is his email response:
quote:
Interesting, but it only makes it even more inexplicable that a
limnologist would make the astounding errors of basic science that
I've seen you make.
It's not out of pique that we're telling you these things. If you
could get over your obviously great infatuation with your own obtuse
metaphors and glib comebacks, you'd find yourself with considerable
opportunities to engage in constructive dialogue.
I'm just an interested amateur with aspirations, and I think it's
pretty clear you don't consider my contributions worth serious
consideration. But you did feel it was important to answer my
questions, I guess. Maybe that says something.
Well, now I feel like Charlie Brown right after Lucy pulled the football away. I should have known better, since I already knew this boy has a real big wad in his underwear.
”HM

This message is a reply to:
 Message 298 by crashfrog, posted 03-27-2007 7:31 PM crashfrog has replied

Replies to this message:
 Message 300 by crashfrog, posted 03-28-2007 10:40 AM Fosdick has replied
 Message 301 by Percy, posted 03-28-2007 11:16 AM Fosdick has not replied

crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 300 of 303 (391970)
03-28-2007 10:40 AM
Reply to: Message 299 by Fosdick
03-28-2007 9:56 AM


Re: Summation
I'm sorry that you weren't able to recognize an overture intended for your benefit, and that you feel that it's appropriate to share private correspondence on a public forum without the sender's permission.
Edited by crashfrog, : No reason given.

This message is a reply to:
 Message 299 by Fosdick, posted 03-28-2007 9:56 AM Fosdick has replied

Replies to this message:
 Message 302 by Fosdick, posted 03-28-2007 11:21 AM crashfrog has not replied

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