[Taxacom] Invisible evolution

[Curtis Clark]

On 2007-06-08 11:53, Richard Jensen wrote:
> I've never been convinced of the logic of this approach. I once 
> discussed this with David Hull, whose reply suggested that he, too, 
> found this puzzling. But, he argued that if a species is an individual, 
> then when one or more populations becomes isolated, it is no longer the 
> same individual. I have wondered why we do not treat the natural 
> extinction of populations the same as the "evolutionary" extinction of 
> populations. 

I've had the same thought (and lectured on it when I used to teach 
speciation). Peripheral isolates are common in many (if not most) 
species. Only occasionally do they survive to become species themselves, 
and the ancestral species has no way of genetically "knowing" which did 
and which didn't.

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