Kluge based his analysis on morphological characters; he has no alternative but to pay attention to morphological characters. Burbrink is only using morphology as an afterthought, to justify the splitting of his taxa on the basis of mtDNA data. The number of precaudal vertebrae in and of itself is not a diagnostic character for anything.



Yes, any taxonomist could have recognized one, two or three genera given Kluge's tree. But the cladists have no guideline other than "one ancestor and all descendants" in delimiting their taxa. They are forbidden by their methodology to recognize paraphyletic taxa even though such taxa may be morphologically homogeneous.



You claim that "Kluge based his reassessment of the New World erycines entirely on morphology, though. He simply decided that the level of morphological disparity he found between Charina, Lichanaura, and Calabaria wasn't great enough to require a generic distinction. A Darwinian could have done the same."



That is not true at all. Kluge made no comments on morphological disparity among these three genera, and based his decision of a single genus for all three on "taxonomic efficiency."



Finally you claimed that recognizing a paraphyletic Elaphe would have resulted in "in perpetuating a morphologically heterogeneous taxon." That is not true at all, since Elaphe was delimited on the basis of morphological similarity by systematists and this genus is thus rather homoegeneous morphologically. The fact that it has proven to be a natural group (monophyletic sensu Darwin) is icing on the cake. There is no scientifically tenable reason to splinter a natural group such as Elaphe, which is also morphologically homogeneous.

[ Show Entire Thread ]