`Not at all, Utiger et al. demonstrate that all species of Elaphe are part of a clade that also include the Lampropeltini. The branching order among these species may not be well supported, but the fact that they share a common ancestor is well supported by Utiger et al.'s study.'



Nope, the grouping of Euprepriophis with the other taxa studied rather than Ptyas is poorly supported. And Ptyas is the outgroup--it's supposed to be distantly related to all of the taxa involved, so a poor support for its outgroup status is particularly damning.



`It is supported by morphological evidence. The N. American species of Elaphe are morphologically similar to Old World Elaphe.'



According to... ? Remember, Pantherophis was sufficiently distinct to be placed in a different tribe from the rest of Elaphe sensu lato long before Utiger's work.



` It is also supported by molecular evidence. Both Lopez and Maxson (1995) and Utiger et al. find that New World Elaphe is part of the Elaphe clade. They have both shown that New World Elaphe is not merely convergently similar to Old World Elaphe but that their similarities are almost certainly due to common ancestry. Since genera such as Pituophis and Lampropeltis are derived from a species of New World Elaphe, Elaphe is paraphyletic because it excludes Lampropeltis and Pituophis.'



This has already been addressed.



`Yes it is found elsewhere since Utiger et al. do not rely on morphological disparity to delimit their taxa. It is plainly obvious that they delimit their taxa according to their consensus tree, which is of course poorly supported as you point out. Therefore their splitting of Elaphe is based on poor evidence on branching order and no evidence from morphological disparity. As such, their taxa are poorly delimited and therefore these taxa should be rejected.'



This, also, has already been addressed.



`The authors of course admit that paraphyletic taxa is the inevitable result of the process of evolution, but it has not stopped them from destroying paraphyletic taxa. I hope it is clear to all what I meant.'



It's certainly clearer than it was. However, until you present a compelling reason to believe that Utiger et al. believe Elaphe sensu lato to be paraphyletic, there is no support for the claim that their split of Elaphe sensu lato represents a rejection on their part of paraphyletic taxa.



Patrick Alexander

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