Re: Rex jaws

["Norton, Patrick" <Patrick.Norton@state.me.us>]

_T. rex_ (and most toothed theropods, for that matter) had a "wrap-around
overbite": the whole upper surface of the lower jaw fits within the   
inside
of the lower jaw. <

That arrangement may have allowed the animal to simply break long bones   
by chomping on them rather than cutting or gnawing them as do mammalian   
carnivores with occlusal teeth.  If a T. rex were to bite down hard on a   
femur, for example, the bone would break on both sides of the mouth at   
the points of contact with the lower teeth.  An overbite in theropods may   
have helped to quickly process a carcass, bones and all, into   
swallow-able chunks by using the leverage of the off-set tooth rows to   
break bones rather than slicing or crushing them.