Posted by:
CKing
at Sat Jul 26 17:46:43 2008 [ Email Message ] [ Show All Posts by CKing ]
>>My personal feeling (opinion) on this group of snakes is that they are so closely related that they should have never been put in separate species,and that the guttatus/emoryi group are all one species with many variants or forms.>>
I agree with that opinion. There are splitters and there are lumpers. The splitters will always keep splitting on the basis of minute differences, and the lumpers will simply ignore those differences. To me guttata and emoryi are the same species. mtDNA data shows that they are part of the same lineage and that the red rat snake is descended from the great plains ratsnake which migrated eastward from Texas.
>>I believe that the form changes with the habitat,>>
Absolutely. Red coloration evolved in woodland habitats with lots of leaf litter because there is lots of red coloration in those habitats. Gray coloration is more adaptive in more open habitats, where red coloration is not cryptic.
>>and all have features unique to themselves. Where one habitat type gives way to another, might not intergrade animals also be found? I think it is far too simplistic to say that slowinskii is just emoryi, or just guttatus. Unfortunately, the current trend in taxonomy seems to be to get rid of subspecies altogether. The latest paper from Collins and Taggart has the group split into guttatus, slowinskii, and emoryi, with no subspecies.
>>
>>-Toby Brock
Collins does not like the subspecies category and he published a short note years ago that attempted to do away with dozens of subspecies all at once. He was roundly criticized for that paper. Apparently he is unrepentant. He and the cladists do not realize that the subspecies concept is useful and that it will continue to be used by biologists world wide.
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RE: Where does emoryi stop and slowinski - CKing, Sat Jul 26 17:46:43 2008