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Posted by TW Taggart on January 21, 2003 at 00:13:13:
In Reply to: reanalysis based on a shift in a philosophical concept??? posted by troy h on January 20, 2003 at 19:40:08:
true, however, a series of workers since that time have considered emoryi to be a ssp of guttata, based on data. Collin's paper presented no new evidence to refute the previous hypothesis of relationships.
Again, the presentation of 'new evidence' is not a prerequisite for taxonomic revisions, alternative analyses of the same data are equally appropriate.
Your statement is also irrelevant to this thread, considering that all published taxonomic changes are considered by a committee of publishing systematists which determine the ultimate makeup of the standard names list.
i do disagree with the idea that emoryi is allopatric from forms variously recognized at "slowinskii" (Burbink) or "brown phase cornsnakes" (Vaughan, et. al.). in fact, solid, hard data does exist for the notion that these two forms are not in fact allopatric, but rather that they intergrade across a wide area in East Texas - see Dixon 2000 or Wehler & Dixon 2000, if you disagree.
Dixon 2000, does cite Vaughn, et al. (1996), and states that the integradation zone was broader than previously known (not quite as bold as your "across a wide area in East Texas"), but his county dot maps show the taxa to parapatric at best.
Oddly enough, if you look at Wehler & Dixon, 2000, and their brief discussion of'corn snake' taxonomy, no statements are made about how the ssp "intergrade across a wide area in East Texas". In fact, their maps show a relatively small area of overlap, confined to two localities in Bastrop County (the Crother et al. names list, also stated the same interpretation).
In fact, the Vaughan, et al, paper does not show any allopatry, and in discussions with these researchers, they assert that there is no allopatry (as will be born out in a forthcoming paper by the same authors).
When your appeal to authority, is actually an authority, the organizers of each list will submit the paper to their respective committees, and it will be evaluated for future inclusion into their respective lists.
furthermore, how does "reanalysis based on a shift in a philosophical concept" qualify as any sort of analysis? All Collins did was look at a published range map that showed populations to be allopatric, and use his new understanding of the ESC and suggest that a bunch of taxa that qualified as "allopatric" by poor field guide-style range maps were in fact distinct species.
You just answered your own question.
Regardless of how "poor" you consider a map to be, it still represents a hypothesis of distribution. And allopatry, in reference to that hypothesis, is a purely objective observation to make. Collins did just what Frost and Hillis suggested, and in doing so has probably done more to advance the discussion of herpetological systematics and taxonomy than any other single article that has appeared before or after. After all, here we a decade-plus later.
on a related note, though . . . why did SSAR, etc, replace Collins with Crother . . . and then why did Collins start up his own competing list (CNAH)? makes you wonder . . .
A better question my be..., why does this matter to you?
I can't answer your first question, because I don't know the answer.
As for your second question, the latest edition of the CNAH list clearly states that it is a continuation of the previous lists (1978, 1982, 1990, and 1997) organized by Collins and formerly published by the SSAR.