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CKing
at Fri Jun 4 09:47:49 2004 [ Report Abuse ] [ Email Message ] [ Show All Posts by CKing ]
"Pantherophis" is a name that has been resurrected by a group of researchers (Utiger et al.), who found that the large holarctic genus Elaphe is "paraphyletic." This group of researchers, like many cladists, are intolerant of paraphyletic taxa. What exactly is a paraphyletic taxon? It is a taxon that does not consist of all of the descendants of a common ancestor. How is Elaphe paraphyletic? According to both morphological and biochemical data, one member of Elaphe migrated from the Old World to the New World. Once in the New World, this species of Elaphe has given rise to a number of new species, which are considered morphologically different enough to be classified into different genera, such as Pituophis, Lampropeltis, Arizona, Stilosoma, Bogertophis, and Cemophora. In order to eliminate paraphyly in Elaphe, species in these genera, no matter how different they are from Elaphe, must be dumped back into Elaphe. Alternatively, the paraphyletic genus Elaphe must be splintered into a large number of morphologically indistinguishable and/or undefinable genera. The second alternative is exactly what the group of researcher, headed by Utiger, have done. Utiger et al. chose to splinter Elaphe into a large number (around a dozen) different contrived genera, even though professional herpetologists such as WW cannot tell us how these genera differ from one another.
The North American species of Elaphe are considered members of two of these contrived genera ("Pantherophis" and "Pseudelaphe" by Utiger et al.
Why are these people intolerant of paraphyletic taxa? It is a long story, but this intolerance has nothing to do with science. It is in fact a quasi-religious belief. A group of scientists have decided that they should follow the teachings of Willi Hennig, a late German scientist who arbitrarily decided that taxa should never be paraphyletic. His followers have decided that this mandate is akin to some sort of gospel and must therefore be followed verbatim.
The splitting of Elaphe guttata by Burbrink into three different "species" has been done for the same reason: Burbrink's intolerance of paraphyletic taxa.
Unfortunately, intolerance of paraphyly, which is characteristic of cladism, or cladisic dogma, is widespread. Therefore it is a matter of time before some "official list" adopts the taxonomic proposals of Burbrink and Utiger et al.
But for those who want to know why Elaphe guttata has been transferred to Pantherophis and why E. guttata has been splintered into 3 different "species", they won't find such an explanation in either Burbrink or Utiger et al. These authors won't tell the readers that they are practicing cladistic religion and that they are on a crusade to rid the world of paraphyletic taxa. They assume that you are also a follower of Hennig and that you already know that paraphyletic taxa are of course not tolerable.
Why should paraphyletic taxa be recognized? Paraphyletic taxa should be recognized because, in short, as Robert Lynn Carroll pointed out, parahyletic taxa are the inevitable result of the process of evolution. As long as evolution produces novelties, these novel species, because they are different from their ancestor, have been and will continue to be classified in a new taxon. For example, when mammals and birds evolved, they were removed from their parental taxon, Reptilia, rendering Reptilia (as traditionally defined) paraphyletic. Removing novel species from an old taxon is therefore necessary if one were to have a useful taxonomy. Doing so, however, results in a paraphyletic parental taxa. Of course, paraphyletic taxa really chaps the hides of the cladists because it contradicts their gospel. They will not rest until all traces of paraphyletic taxa have been removed our taxonomy even though the elimination of paraphyletic taxa is, according to Ernst Mayr, impractical, destructive and scientificallly untenable. Since not all scientists (for example Ernst Mayr and Stephen Jay Gould) are cladists, the cladists' taxonomic proposals are often ignored by the knowledgeable scientists such as Mayr and Gould, even though many amateurs and ordinary scientists who do not know better and often blindly follow the latest taxonomic proposals.
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