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RE: Species & Giraffe necks



Derkits, Gustav E, JR wrote:
> 
>       I'm glad to see someone on the professional side recognize the
> undefinability of species. The Grants' work on finches shows the
> problem in action - species can define and undefine themselves
> by hybridization. 
>       A mathematical note: If the definition of a species 
> requires that a surface be drawn in either sequence space or 
> design space that separates two species, then Turing's theorem 
> and the Blum-Shub-Smale theorem on recursive systems both
> show that "species" is, in general, undefinable. 
>       That doesn't mean the concept isn't useful.
> G. Derkits

        I think a rather lot of us on the professional end of things feel 
this way.  It is one area that is just as cloudy in neontology as in 
paleontology.  However, it is acute in paleontology when the system 
rewards the naming of new taxa.  I think this list is an excellent place 
to cite examples of that process in effect...
It is difficult to devote energy to it, but some of us are trying...



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Josh Smith
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