>>Hi
>>
>>The work by Faivovich et al is available online at the American Museum of Natural History site - very interesting stuff
>>

Thank you. Nevertheless, what some workers may do taxonomically with one taxon really has little effect on what should be done taxonomically with another group. For example, if one group is split on the basis of intolerance of paraphyly, it should have no effect on the validity of other paraphyletic groups. As some biologists have pointed out, paraphyly is the natural consequence of the process of evolution. Classifications that recognize paraphyletic groups are therefore natural. The intolerance of paraphyletic groups is therefore artificial and such intolerance has nothing to do with nature or evolution.

>>As for Elaphe - well i actually thing that personally that its quite strange to group eg. Elaphe scalaris together with Elaphe situla and Elaphe guttata - none of them seem to have anything in common (other than being colubrids). I have keept all three species and find it very weird that anybody has even considered grouping these together (especially scalaris is VERY unlike any other Elaphe)
>>
>>-----
>>Regards
>>
>>Jan Grathwohl

The problem with Elaphe is that it is a generalized group without too many morphological specializations. It is indeed difficult to define this group. Those species that are closely related to Elaphe but that have shown some morphological distinctness (e.g. Bogertophis, Arizona, Pituophis, Lampropeltis, Stilosoma et al.) have been removed from Elaphe and classified in other genera. The remaining species still retained in Elaphe are there because they haven't changed enough morphologically since they diverged from their common ancestors. Elaphe is thus a slowly evolving, paraphyletic group.

Some biologists are, as I pointed out, intolerant of paraphyletic groups because they agree with Hennig that paraphyletic groups should be disqualified from biological classifications. The problem with splitting a paraphyletic group like Elaphe is that the resulting genera cannot be morphologically distinguished from one another. Another problem is that the plethora of new genera really sheds no light on the close relationships among them and may mislead people into thinking that they are transferred to many different genera because they are not closely related. There is thus no gain in information by splitting Elaphe. All that we will "gain" is taxonomic chaos.

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