A snake skull is pretty obvious too, and I'm sure many of us have picture to verify some of the injuries we have received from said beasties. I just got a new one myself last night. (though from a python, not a boa.) And both pythons and boas (I'm pretty sure all snakes) use their teeth to pull prey into their mouth as they swallow. They have what's called a Kinetic skull, which can move and articulate in far more ways that ours can (as you guys have no doubt noticed if you have ever watched one eat!) Thanks for the pic BlackJack!