[Taxacom] Invisible evolution, paraphyly

[Curtis Clark]

On 2007-06-11 07:58, Richard Zander wrote:
> Maybe there's a problem with species definitions, Curtis. Could you tell
> us, in short, what the difference is between paraphyletic species and
> paraphyletic higher taxa.

Reptilia is a paraphyletic higher taxon. Its existence depends on a 
classification decision by people, not by the mode of speciation of the 
first bird or first mammal.

Speciation by peripheral isolation ordinarily results in a paraphyletic 
ancestral *species*. As has been pointed out repeatedly, systematists 
often disagree about the circumscription of species. But anyone who 
claims that the amniotes minus the mammals and birds constitutes a 
*single species* is clearly not using any of the plethora of definitions 
to come out of my generation of systematists. I continue to maintain 
that anyone who uses the existence of paraphyletic species as a 
justification for the Reptilia isn't interested in evolution as a process.

-- 
Curtis Clark            http://www.csupomona.edu/~jcclark/
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