[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Question

Patrick Norton wrote:
> I feel as bit foolish posting this, but I can't find an answer anywhere.
> Generally, when a reptile is depicted with its mouth open (dino's included)
> a flap of skin is usually shown stretching between its upper and lower jaws
> near the joint. That membrane is present in extant reptiles, but what is it
> called? What is its purpose?

These are the jaw adductor muscles, that are used to close the jaws.

> Is it possible that some dinosaurs exapted this membrane to serve as a type
> on non-muscular "cheek" (I'm thinking of the Ornithopoda  in particular)?

Jaw adductor muscles seem to be connected to the inside of the
mandibles and skull. I suspect that ornithopod "cheeks" (if they
existed) would have been adapted from muscles or skin on the outside
of the jaws.

Disclaimer: I may have got all of this completely wrong, so don't
quote me!
        Dann Pigdon
        GIS Archaeologist
        Melbourne, Australia

        Australian Dinosaurs: