So, you are subscribing to the hypothesis that "the common ancestor of the racers and ratsnakes is venomous and the genus Elaphe has since lost its venomous ancestry completely without a trace"



There are several problems with that scenario.



1. Fry et al. present no data to support any member of the genus Elaphe has any trace of a venomous ancestry. So they are guessing.



2. Fry et al. can provide no plausible explanation why the lampropeltines should lose venom.



BGF claims that a shift in diet from ectotherms to rodents is responsible for the loss of venom but I pointed out that Ptyas eats rodents, but it has not lost its venom. Neither has the viperids. Rattlesnakes feed largely on rodents, and they are more venomous than the copperhead, which feed largely on ectotherms. So a predominantly rodent diet should at least favor the retention of venom rather than losing it. You can map your character over a tree, but that does not explain seemingly maladaptive changes. Maladaptive changes are possible on a tree, but they are very difficult to achieve in nature.



"And I've pointed out that its not homoplasy but rather useful ancient tools being misunderstood by recent useless tools."



Yes you made that claim. But like your other claims, it makes no sense. And it is contradicted by scientific evidence. The Pax-6 gene is found in the development of all sorts of things, not just the eye, and the only plausible explanation is that it has been co-opted many times independently and convergently by different groups of animals to regulate eye development.



"Then we are in fundamental agreement since some toxin lineages form monophyletic groups (and thus are ancestral) while others (e.g the PLA2 toxins) form two separate monophyletic groups (and thus represent independent recruitement events)."



Unfortunately we are not in any agreement. You still believe that similarity means homology. That is simply borne of ignorance. Experienced systematists would not be as easily fooled by the insidious trap of convergent evolution as Fry et al. were.

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