I wonder why Kurt Schwenk, evolutionary biologist, thinks the evidence that
Komodo dragons are venomous is not convincing. Bryan Fry dissected jaw tissue from a terminally ill lizard, and found venomlike proteins that keep blood from clotting and others that lowers blood pressure. This seems like fairly indicative evidence to me, but Schwenk calls it “meaningless, irrelevant, incorrect or falsely misleading.” Strong words indeed.
Even if the lizards have venomlike proteins in their mouths, Dr. Schwenk argues, they may be using them for a different function.
Sure, but the simplest hypothesis seems to be that they are used for attack.
Dr. Schwenk also doubts that venom is necessary to explain the effect of a Komodo dragon bite. “I guarantee that if you had a 10-foot lizard jump out of the bushes and rip your guts out, you’d be somewhat still and quiet for a bit,” he said, “at least until you keeled over from shock and blood loss owing to the fact that your intestines were spread out on the ground in front of you.”
Look, the effect of the proteins found in a gland in the mouth of the Komodo dragon are known to have the effect that its bite has on its prey. That's not conclusive evidence - finding those proteins in prey would help - but I am curious why Schwenk is so dismissive.
The study's methodology was highly flawed. Showing some shared proteins with snake / gila monster venom, and that some of the proteins in doses not necessarily biologically relevant are harmful (they are digestive compounds and enzymes), does not prove in any way that the lizards are using venom to kill their prey. There's a high probability this research will be debunked over the long haul, but Fry sure is getting some limelight for it.
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