`Very good question. Darwinians do not distinguish between paraphyletic taxa and monophyletic (sensu Hennig) taxa. All paraphyletic taxa are monophyletic according to the Darwinians since both types of taxa share a single common ancestor. Since Darwinians find it scientifically tenable to splinter monophyletic (sensu Hennig) taxa on the basis of morphological disparity, it is therefore scientifically tenable to splinter paraphyletic taxa on the same basis. On the other hand, splintering monophyletic (sensu Hennig) or paraphyletic taxa without a valid reason is scientifically untenable.'



Morphological data aren't the only valid data, though. Evidence of genetic disparity is, these days, generally considered to be of greater importance and utility in taxonomy, though only the hardcore cladists (Burbrink comes to mind) are willing to use it to split a taxon into morphologically indistinguishable taxa.



I'd guess that Utiger et al. don't explicitly mention morphology for some of their taxa simply because the morphological disparity among the members of Elaphe sensu lato is so conspicuous and has been previously reported often enough that they figure their readers are already well aware of it.



`Any two species, unless they are diploid-polyploid species pairs, are morphologically disparate. So it is not hard to find morphological disparity between closely related species most authors classify in the same genus. The question is whether the amount of morphological disparity rises to genus level.'



And that question is simply a judgment call--they could provide all the data on morphological disparity they wanted, and still have no objective means of demonstrating that the disparity is `enough'. I think most people familiar with Elaphe sensu lato will agree, though, that the disparity is indeed enough for generic distinction to be appropriate.



`Utiger et al. simply do not provide any data on morphological disparity to justify their taxonomic proposal to remove a large number of species from Elaphe and place them in other genera.'



See above and previous discussion. The data had already been presented by other authors.



`Since they also provide no evidence to support a polyphyletic Elaphe, they have provided no scientifically tenable reason to justify their highly destructive taxonomic proposal.'



I continue to disagree with your assessment of the data as regards polyphyly. I suppose that's not a shock at this point...

And anyways, what good's it do anyone to have all these different taxa lumped in together in Elaphe sensu lato? It keeps the generic name from conveying any useful information.



Patrick Alexander

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