RE: infuriating Bakker

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

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> longrich@alumni.princeton.edu
>
>       I was pretty frustrated by some of his reasoning. For example he
> cites the mediolateral expansion of the teeth in allosaurids as making
> them stronger to better resist being drawn backwards. This is true, but
> expanding them anteroposteriorly- as in sabertoothed mammals- would make
> them far stronger for the same amount of material.

Yes, exactly.  See:
FARLOW, J.O., D.L. BRINKMAN, W.L. ABLER and P.J. CURRIE.  1991.  Size,
shape, and serration density of theropod dinosaur lateral teeth.  Modern
Geology, 16:161-198.

VAN VALKENBURGH, B. and C.B. RUFF.  1987.  Canine tooth strength and killing
behavior in large carnivores.  Journal of Zoology, London. 212:379-397.

>       In terms of dentition, sabertooths tend to have exceptionally long
> upper teeth which are mediolaterally compressed. In other words the
> teeth are... saber like. _Ceratosaurus_ seems to fit this bill pretty
> well, _Allosaurus_ doesn't, where the teeth are perhaps better described
> as chisel like in being so short and massive. Another thing that occurs
> to me is that sabertooth cat teeth are serrated if I recall, it would
> make sense to see which if any theropods the cat teeth most closely
> resembled.

The Farlow et al. paper included sabrecats and a variety of other
serrated-toothed non-theropods along with various theropod groups.  Since
many theropods plot along the same allometric curve in terms of density of
dentition, and since many other taxa fall along the same curve, they may not
match any particular one clade of theropod.  Will have to go back to the
paper to doublecheck.

                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
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