Perhaps there are valid points on both sides of this argument:

James J. Roper, Ph.D. wrote:

> Natural selection is not a judge.  It is only differential 
> representation of genes in subsequent generations, in which more 
> successful genes become more common from one generation to the next.  
> Sure, natural selection can be occurring while extinction is taking 
> place, but the extinction is NOT the result of natural selection.

It seems to me a bit arbitrary to accept that natural selection is 
taking place when a certain fraction of individuals are selectively 
culled from a population, yet when that fraction reaches 100% that 
something different is necessarily going on. To be sure, the RESPONSE of 
a population to natural selection when mortality is 100% will be a moot 
point (unless one is considering selection of higher scale entities, 
dare I say groups?), but to deny that the same processes are at work 
seems like a bid for special treatment.

Wirt Atmar writes:

>In my continuing bid to become the group's curmudgeon, let me say that 
>natural selection can quite easily select for extinction.

I might argue a semantic point here. While you make a valid argument that past 
natural selection can lead to evolutionary dead ends and extinction, I don't 
think it is accurate to say natural selection is selecting "for" extinction 
itself. Rather, natural selection "for" certain traits (other than 
extinction-proneness) may ultimately lead to extinction. A minor point perhaps, 
but an important distinction.

Hope this is a helpful contribution to an interesting discussion.
Norris


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Norris Z. Muth

Department of Ecology and Evolution
State University of New York at Stony Brook
650 Life Sciences Building
Stony Brook, NY 11794-5245

[EMAIL PROTECTED]
http://life.bio.sunysb.edu/~nmuth
http://life.bio.sunysb.edu/ee/pigliuccilab/
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