Posted by:
RSNewton
at Thu Aug 7 20:36:51 2003 [ Email Message ] [ Show All Posts by RSNewton ]
You wrote:
It is very evident that North American "Elaphe" are more closely related to Lampropeltis, Pituophis, and other North American snakes, than they are to any of the Eurasians.
My response:
Scientific evidence does show that a number of North American snakes, including those in the genera Pituophis, Arizona, Cemophora, Lampropeltis and of course Elaphe, are descended from a Eurasian species of snake (most likely a species of Elaphe) that migrated to the New World in the Miocene. Some of these New World species have been classfied in several different genera because they have changed morphologically and differ from their Elaphe ancestor. Those species that have not changed morphologically are currently retained in Elaphe. There are some scientists who "assume" that Elaphe is polyphyletic, meaning that the species currently classified in this genus are only similar due to convergent evolution. Utiger et al. (2002), as well as a number of other papers, including one that Utiger et al. ignored (Lopez and Maxson 1995) clearly show that Elaphe is NOT polyphyletic. That means the similarities between Old World and New World Elaphe are due to common ancestry, not convergent evolution. Many scientists would argue that New World Elaphe is more closely related to Old World Elaphe because they share more similarities with each other than New World Elaphe does with Lampropeltis, Arizona and Pituophis. To codify this view, they have retained E. guttata, E. obseleta et al. in Elaphe. Utiger et al. have a different idea of what related means. They therefore propose a transfer of New World Elaphe to Pantherophis and "Psuedelaphe." Not all scientists subscribe to Utiger et al.'s ideology. I predict they will reject the resurrection of Pantherophhis and the new genus Pseudelaphe. There is nothing "pseudo" about the morphological similarity between Old World and New World Elaphe; their similarity is due to common ancestry. There are many scientists who, unlike Utiger et al., would never erect a new genus (or resurrect an old genus) for species that have not changed from the parental genus. These scientists would probably reject Utiger et al.'s destructive and scientifically untenable taxonomic proposal.
[ 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 - Matt Campbell, Thu Aug 7 11:17:37 2003
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RE: Pantherophis, a preliminary review - RSNewton, Thu Aug 7 20:36:51 2003