`Below is a simplified version of Utiger et al.'s weighted MP tree (fig. 3). It illustrates the fact that New World Elaphe and the Lampropeltini is very much nested within Old World Elaphe. Elaphe is not polyphyletic. It is however, paraphyletic.'



Unfortunately, though, the simplified version is too simplified to demonstrate anything.



` Removing the Lampropeltine snakes from Elaphe is similar to removing birds from Reptilia. The cladists do not like it, but it is perfectly acceptable to the Darwinians or traditionalists to accept a paraphyletic Reptilia (minus the birds and mammals) and a paraphyletic Elaphe (minus Lampropeltis, Arizona, Pituophis among others). There are two courses of action available to the cladists: dumping species classified in Pituophhis, Arizona and Lampropeltis et al. back into Elaphe, or splintering Elaphe into many different genera that are not morphologically distinguishable from one another. The Darwinians have a better alternative not available to the cladists: Keep Elaphe paraphyletic and recognize Pituophis, Lampropeltis, Arizona et al.'



You appear to be under the impression that Utiger et al. split Elaphe in order to adhere with cladist methodology. This is another instance in which having read the paper is useful. In reference to the possibility that Pituophis arose from within Pantherophis, something suggested by other authors and by one of the phylogenies generated with their data, they write that paraphyletic taxa are `an inevitable result of evolution.' Helfenberger, one of the coauthors of the study, also created the genus Rhinechis for what was Elaphe scalaris even though the data he presented at the time showed that Rhinechis was nested within European Elaphe. The option of creating paraphyletic taxa clearly was open to Utiger et al.



I also disagree that the genera created are `morphologically indistinguishable.'



Patrick Alexander

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