Posted by:
RSNewton
at Thu Aug 7 23:33:54 2003 [ Email Message ] [ Show All Posts by RSNewton ]
Wolfgang wrote:
Correction: a number of species groups are highly supported. The relationships *between* these species groups are unsupported and unresolved.
My response:
May be it does not bother you that the base of their tree is unresolved. It bothers me. It shows that phylogenetic relationships within the genus Elaphe is far from resolved. Kluge, when he found a similar situation in his study of the Erycine boids, dumped all species of the polytomy into the same genus--Eryx. Utiger et al. adopt the opposite taxonomic extreme. They split Elaphe into 10 different genera, none of which can be adequately distinguished from the remaining. That shows that one can simply flip a coin in such a situation since the decision between 1 genus and 10 genera is totally arbitrary. I demand that Utiger et al. flip their coin a second time, because it may result in a completely different outcome: a single genus instead of 10 genera.
Wofgang wrote:
Taxonomic chaos by the truckload? Hardly. History suggests that after a few years of readjustment, these changes get absorbed fairly easily. Who, today, still uses Bothrops schlegelii or Bothrops nasutus instead of Bothriechis schlegelii and Porthidium nasutum?
My response:
Yes, people do get used to new names but why inconvenience ourselves with unncessary name changes? I simply question the need for any of the new names. None of these genera is morphologically distinct enough to warrant recognition. Sure, taxa can and should be split if they are polyphyletic. But there is no evidence that Elaphe is polyphyletic. In the absence of evidence for polyphyly and for morphological distinctness, the proposed taxonomic changes are indeed scientifically untenable.
Wolfgang wrote:
nothing will ever convince you that classification should follow phylogeny.
My response:
Classification should indeed follow phylogeny. It is just that we have different interpretations of what phylogeny means. The genus Elaphe is not polyphyletic. A single genus is consistent with Utiger's phylogeny. In fact, it is a better fit for Utiger's unresolved phylogeny. If the Lampropeltini never evolved, then the cladists would not have sent the genus Elaphe to the chopping block. But why should a morphologically conservative genus such as Elaphe be splintered because one species crossed a land bridge and evolved into a number of different disparate taxa in the New World? What happened in the New World did not change Old World Elaphe in any way. So, why should new genera be proposed in a group in which there have been no recognizable evolutionary changes?
[ Hide Replies ]
- Pantherophis, a preliminary review - RSNewton, Tue Aug 5 00:29:14 2003
- RE: Pantherophis, a preliminary review - jfirneno, Tue Aug 5 19:28:42 2003
- RE: Pantherophis, a preliminary review - Terry Cox, Wed Aug 6 11:34:07 2003
- RE: Pantherophis, a preliminary review - patricia sherman, Wed Aug 6 15:20:03 2003
- RE: Pantherophis, a preliminary review - WW, Thu Aug 7 03:19:24 2003
 RE: Pantherophis, a preliminary review - RSNewton, Thu Aug 7 23:33:54 2003
- RE: Pantherophis, a preliminary review - Matt Campbell, Thu Aug 7 11:17:37 2003
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