You wrote:

I hate to nitpick, but Coronella, Lampropeltis, Arizona, Pituophis, Bogertophis, and Senticolis are all called `ratsnakes' in informal terminology (Lopez and Maxson call all members of Lampropeltini `ratsnakes' for instance) but these obviously are not Elaphe.



My response:

The common name of the species classified in Ptyas is also ratsnake. Lopez and Maxson is calling Ptyas a racer. All of the racers in Lopez and Maxson's paper falls outside of the "ratsnake" clade, including Gonyosoma, which is another racer that has the common name of "ratsnake." The important thing to remember is that all species of Elaphe recognized by most taxonomists form a clade with the Lampropeltini. Lopez and Maxson call this clade ratsnakes. I have no problem with it. After all the Lampropeltini includes species that are not in Lampropeltis.



You wrote:

No. Only four species of Elaphe (five if you wanted to include Rhinechis scalaris--a taxon created explicitly on the basis of morphological disparity, for what it's worth) share a more recent common ancestor than the other taxa in Lopez and Maxson's study. Without data about all of the members of Elaphe sensu lato, no conclusions can be reached about all of the members of Elaphe sensu lato.



My response:

The claim that Utiger et al. delimited Elaphe on the basis of morphological disparity is unsupported. I am not sure what you mean, but as I said, all of the species of Elaphe in Lopez and Maxson are more closely related to each other than they are to Ptyas or any other racer. Similarly, all of the species that other folks have classified in Elaphe (but which Utiger splinter into many different genera) are also more closely related to each other than any of them is to Ptyas. That is strong evidence that Elaphe is not polyphyletic, and Tong et al. (Acta Zoological Sinica) independently verify this fact in their study.



You wrote:

"My conclusion (which I had thought was obvious) is that the difference in outgroup support for Ptyas between Lopez and Maxson and Utiger et al.'s studies supports polyphyly of Elaphe sensu lato. Your conclusion, apparently, is that they suggest flaws with Utiger et al.'s data.



My response:

You are suggesting that a difference in the amount of statistical support for Ptyas as an outgroup between the two studies is evidence of polyphyly of Elaphe? That is an unsupported interpretation of the available data. The only way Elaphe can be polyphyletic is if some of them form a clade with Ptyas to the exclusion of other species of Elaphe. Neither Lopez and Maxson nor Utiger et al.'s data shows that. Tong et al.'s study also include Ptyas. Like the other two studies, theirs also show Ptyas outside of the Elaphe clade. "Your conclusion" is simply unscientific.



You wrote:

In the face of multiple independent studies concluding that Elaphe sensu lato is polyphyletic? Even if you don't think it's -good- evidence, there clearly is evidence.



My response:

You are obviously influenced by Utiger et al.'s single sentence on page 105, in which they claim that several authors "...concluded that Elaphe auct. as presently understood represents a large polyphyletic group." One of the papers they cite is that of Dowling et al. (1983). Dowling et al. do not include any of the Old World Elaphe species in their study. Therefore they have no data to show that Elaphe is polyphyletic; they are merely speculating. Tong et al. (2002) also conclude that Dessauer (another paper cited by Utiger et al.) assumes that Elaphe is polyphyletic. Further, Utiger et al. fail to cite Lopez and Maxson (1995), which clearly shows that Elaphe is a monophyletic group (paraphyletic if the Lampropeltini is excluded). It appears that Utiger is including studies that speculate on the polyphyly of Elaphe and at the same time overlooking those that refutes polyphyly. If that is the source of your "multiple independent studies concluding that Elaphe...is polyphyletic," then you have been misled by Utiger et al.



You wrote:

And, predictably enough, I'll continue to disagree.



My response:

You may disagree all you want, but if your disagreement is unsupported by scientific evidence, then it is a meaningless disagreement.

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