Penguins And Rexes

["Richard W. Travsky" <rtravsky@uwyo.edu>]

Saw "March of the Penguins" earlier this week, and noted something I
hadn't before about penguins (not unexpected when they're on screen
in front of you for almost 2 hours).

They had two ways of getting up when traveling on their bellies.

One, obviously, pushing up on their flipper arms. 

The other was pushing up with their beaks, with no arm usage.

So, question - In the past there's been mention in the list of how
rexes got up, what with those tiny arms and all. I don't recall if
anyone proposed pushing up with their jaws. That would seem like
a lot of weight to raise. Do their jaws look sturdy enough to 
do that? Do their jaws show signs of being used in this fashion?