Re: T.rex jaw power: T.rex predation revisited

["Thomas R. Holtz, Jr." <th81@umail.umd.edu>]

At 06:42 PM 5/3/99 -0500, Mike "megaraptor" Hickman wrote:
>    I remember seeing a small article about the strength in the
>Tyrannosaur's feeding bite and it said that it was 3,011 lbs if pressure
>per square inch.  The reason why I am posting this and emailing these
>two well known Paleontologists is that it pertains to T.rex predaition.
>If the strength behind the attacking bite of the T.rex is more powerful
>than the feeding bite it must have been a true predator

(In a bit of a snit, I would like to point out that certain
not-quite-so-well-known-as-Jack-and-Paul paleontologists on the dinosaur
list are tyrannosaur specialists, unlike Horner and Sereno... :-S  ).

But, to answer your question:
In fact, the strength of the _T. rex_ bite does not demonstrate that it was
a predator.  A powerful scavenger can also benefit from a very powerful bite.

What the analysis of Erickson and others DOES do, however, is reject
previous assertions that the jaws and/or teeth or _Tyrannosaurus_ would have
been too weak to have withstood the forces associated with taking down big prey.

So, to make things clearer, a powerful _T. rex_ bite gets rid of one
argument against tyrannosaurids being predators, but it doesn't show that
they must have been predators.

(Of course, I happen to think that there is substantial evidence to support
the idea of tyrannosaurids as both predators and scavengers, but that's
something that has been covered a lot on this list.  Check the archives, or
the next DinoFest volume (when that comes out) for some of my evidence).

Thomas R. Holtz, Jr.
Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
Dept. of Geology              Email:tholtz@geol.umd.edu
University of Maryland        Phone:301-405-4084
College Park, MD  20742       Fax:  301-314-9661