... indeed it is a most interesting aspect to these snakes. I've always wanted to observe how a color sensitive predator such as a bird or collared lizard might react to this display, but as yet have not conducted the experiments. Theres a book out in print by Rossi I believe that gives an interesting acct of a captive long nosed snake consuming a florida ringneck (tailcoiler) and the result being the Rhino died and the next am the ringneck was crawling about. Thus I suspect the tailcoilers are inclined to bite the mouth linings of would be predators.
The venom of regalis on cold blooded prey works as fast or faster than coralsnakes, (see herptoculture subforum on necropsies for a visual) so the deterrence factor appears to be there. The drooling often seen in freshly captured ringnecks may very well be them preparing to give the kiss of death!
The very similar tail coiling in the elapid; Calliophis is possibly convergence, but furthur indicates to me the likely elaps origins of Diadophis. Interesting too, is how quickly w/c regalis stop exhibiting this warning, I rarely get more than 2 or 3 full on displays if i choose to keep a wild specimen.
A final conundrum is the non tail coiling northerns which I have no experience w/ are reportedly much more prone to try to bite when handled than are their southern redtailed cousins, who apparently wait for their shot ...
