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Hello,

I good friend of mind mentioned to me that he had stumbled across a new study of the genus Pituophis which helped to shed light on the relationship between them and North American Ratsnakes (I cant recall the new genus name off the top of my head ; ; ) Unfortunately he only saw it in passing and dosent have the time to locate it for me since he is working on his thesis.

Have any of you heard of this study and can anyone point me in the right direction?

Thanks in advance,
Jeremy

I think what you may be referring to is the latest from Burbrink. A link to this,

http://www.cnah.org/pdf_files/687.pdf

From what I hear this is basically a proposal and has not gained universal acceptance at this point. My guess is it probably never will, but thats just my take on it.

Phil

Thank you for providing that link Phil! I have only breifly scrolled through it but did locate atleast one part were they clumped Pituophis in.

I have to agree with you in my gutt but on the same note it is hard to question DNA results. However, there is clearly a distinction between the genera in many obvious regards and although they may be closely related I feel their distinction was over looked or down played.

I will keep reading a comment further once I attempt to crasp the authors information. Interesting stuff indeed.

Thanks again Phil!

All the best,
Jeremy

>>I have to agree with you in my gutt but on the same note it is hard to question DNA results.
>>All the best,
>>Jeremy

I have to disagree with this statement. In fact I find it very easy to dismiss genetic data. There is an example similar to this in turtles I will mention. I provided blood from some rare species so I got inside info.

STUDY: Test DNA of all American species of turtle.

CONCLUSION: Most species of USA turtle are the same species. Redears, paineted, cooter maps and diamondbacks all the same species.

COMMON SENSE OPPOSING NON GENETIC EVIDENCE: Never mind the fact some rivers in the south have 5 taxa of turtles in them. If they were the same species the taxa could not stay segregated in the same river.

PROBLEM: We all know DNA evidence is capable of seeing individual specimens. The wrong research criteria could concluse every SPECIMEN is one species.

DNA is separated into something called "base pairs". If the wrong combination of base pairs is chosen for the study then the evidence is, at best, suspect and, at least worthless.

Common sense tells us Pits are NOT ratsnakes. Reproduction is all different with different egg size. Keeled scales, eyes and other morphological evidence. If a scientist is blind to all of this because of his reliance on DNA then his science is bad.

With respect to this paper and its conclusions. I read the paper and it indicates Fox snakes (Pantherophis {Elaphe} vulpina) and Pits have a common ancestor, does not make the conclusion Pits are the same genus as ratsnakes.

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Is there a reference to that turtle study anywhere? It's one thing if someone in the lab says something based on preliminary results, and another if it's published in a peer-reviewed journal.

Regarding the Pituophis/rat snake question, the issue isn't whether Pituophis are distinct from rat snakes in terms of morphology, the issue is what their phylogenetic relationships are, i.e., who shares the most recent ancestor. That's what decides taxonomic placement, not how superficially different these forms are. What Burbrink's results basically tell you is that Pituophis are highly modified rat snakes that evolved from a common ancestor with other rat snakes that would have looked like a rat snake. The classification proposed by Burbrink simply highlights that evolutionary relationship. The results are fairly strongly supported, so I suspect that they may well stand the test of time.

Cheers,

WW
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