T. rex overbite

[<quailspg@frii.com>]

LISTERS --

Adult T. rexes seem to have a noticeable overbite. This malocclusion begs
the question of how the fleshy, upper-teeth-covering lip model might have
worked. A *lot* of extra gum and lip tissue would be required on the
mandible to meet the upper lip.

Does anyone know of other animals -- living or extinct -- that have/had a
pronounced over- or underbite that could be used as a model for the rex
mouth?

OR!!!!!!!!!!!!!!

Does simple bracketing answer the question:

crocodilians (no lips) -->  theropod dinosaurs (no lips) -->  living birds
(no lips)

Or does the fact that living crocs are all aquatic and the condition in
ancestral crocs is unknown muck this up?


-- Donna Braginetz