I will consolidate my replies to both of your posts, in the interest of taxonomic discussion efficiency.



You wrote:

Utiger et al. also include many taxa not included in Lopez and Maxson's study, or any other studies I've seen of colubrine phylogeny, such as the members of Euprepriophis and Othriophis.



My response:

These are Elaphe according to most taxonomists. Yes Utiger et al. include more ratsnakes (all of which are members of the genus Elaphe according to most taxonomists) in their study than most authors, but it does not change anything. All of the members of Elaphe share a more recent common ancestor with each other than any of them does with any racer, including Ptyas, in Lopez and Maxson (1995). The same is true in Utiger et al. All members of Elaphe (including E. mandarina and E. conspicillata) share a more recent common ancestor with each other than any of them does with Ptyas. There simply is no evidence that any of the large number of ratsnake species in Utiger et al.'s study is more closely related to the racers than to each other. In other words, there simply is no evidence to support the oft-repeated claim that Elaphe is polyphyletic.



You worte:

If Elaphe sensu lato is mono- or paraphyletic, inclusion of these taxa shouldn't result in reduced support for the outgroup status of Ptyas. Yet their inclusion does reduce this support. I know what my conclusion is.



My response:

I don't know what your conclusion is but I do know that there is no evidence Elaphe is polyphyletic.



`Since there is no evidence that Elaphe is polyphyletic, and since there is no evidence that Utiger et al. split Elaphe on the basis of morphological disparity, the only reason I can think of is an ideological intolerance of paraphyletic taxa. If you can think of another reason for their splintering of Elaphe, please let us know what it may be.'



You wrote:

Again, this has already been addressed.



Patrick Alexander



My response:

You have denied that they splinter Elaphe because of an ideological intolerance of paraphyly. But you cannot provide evidence Elaphe is polyphyletic and you cannot provide evidence that Elaphe is a morphologically disparate group. If there is a fourth reason why they splinter Elaphe, I don't know what it may be. Therefore I will maintain that they splinter Elaphe because of their scientifically untenable intolerance of paraphyletic taxa.

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