>>What I was wondering was if isolating the venom would enable us to be more accurate comparing genera or species in genera with large numbers of species.



It is certainly a character worth comparing. However, we have looked at venom as a taxonomical tool and found that it evolves at such a sizzling rate that the taxonomical signal quickly becomes blurred, even between closely related species.



>>

>>I have a question as a result. Do you think that Coelognathus, which contains 'radiatus', the species you got the venom from, represents an independent family?



Not a chance. It is a typical member of the Colubrinae snake family and is nothing special by being venomous since this is the basal condition.



>>



>>

>>A couple more questions. Do you think any of the species that remained in the Elaphe before Utiger et al. possess the venom that radiatus does? Do you think any of the other species in Coelognathus possess this venom? How about Gonyosoma?



Yep. Have a look at the publications section of my webpage. In the LC/MS study we showed the widespread presense of venom (including in other such typical 'non-venomous' snakes such as Gonyosoma).



>>

>>I think more work needs to be done on the Elaphe to resolve problems with that genus and also would suggest that the genus should still be in the same family and subfamily with Coelognathus and Gonyosoma even if they don't have any venom and the others do.



They all do. The only exception may be the narrow American clade containing such genera as Lampropeltis/Pantherophis/Pituophis. It 'appears' that the common ancestor had undergone a secondary loss of the venom and reverted back to the more primative constricting condition. We are working on that right now to sort it out one way or the other. Loss of venom is not without precedent, it has occured even within the highly advanced venomous snakes sucha as the elapids. Two lineages of sea snakes for example have independently gone well down the road towards losing their venom entirely since they are specialising in eating fish eggs, their fangs are stubs and the venom glands greatly atrophied. Similarly, the Australian coral snakes (Simoselaps) eat termite eggs and are also evolving towards a non-venomous state.



> I believe Utiger et al. did a good job with their research. Good to be moving forward with ratsnake taxonomy. I'm also happy to see the work you're doing with the venom research. I'll be looking forward to future articles. Thanks,

>



Fangs for that mate.



Cheers

Bryan
-----
Dr. Bryan Grieg Fry

Deputy Director

Australian Venom Research Unit

University of Melbourne



www.venomdoc.com

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