RE: Tyrannosaur predation strategy

["Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>]

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> Larry Dunn
>
> At the risk of being tedious with another tyrannosaur
> question, can someone briefly summarize what the
> current thought is on tyrannosaur predation strategy?
> (Or tactics, I guess.)
>
> What exactly do the unusual shape of the teeth and the
> broad muzzle mean in terms of possible attack
> strategies?  I read through the Farlow and Holtz paper
> on this, but didn't see the fiddly specifics
> addressed.

Some more specifics are addressed in my paper in the Plenum Press
Predator-Prey chapter (sorry, no .pdfs or reprints yet).  Also, have a paper
in prep that I REALLY want to get finished up this summer that addresses it
in far more detail.

> Were the Tyrannosaurs biting and pulling out chunks of
> their prey to incapacitate it?  If so, wouldn't that
> strategy be better accomplished by a narrower muzzle,
> and flatter teeth?

And indeed what you describe has been suggested for _Allosaurus_ by Rayfield
and colleagues, by Bakker, and (even more broadly among _Ceratosaurus_ and
basal tetanurines) by me.

> Were they biting and crushing, keeping with the prey
> immediately after the bite was inflicted?  I seem to
> recall Bakker writing something to that effect.

Yeah, and that is what I deal with to, to a degree.

> How is this reflected, if at all, in the fossil
> record?

Okay, among other things (and in brief):
*Deeply rooted lateral teeth
*Incrassate rather than ziphodont tooth proportions
*Broader snout, and broader occipital region
*Possibly even fused nasals...

and, in terms of trace fossils:
*Bite marks and crushed bone
*The tyrant turd

Hope this helps,

                Thomas R. Holtz, Jr.
                Vertebrate Paleontologist
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
                College Park, MD  20742
http://www.geol.umd.edu/~tholtz/tholtz.htm
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
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