Re: Suchomimus feeding (was Re: Paleo-Ring)

[chris brochu <cbrochu@fmppr.fmnh.org>]

>
>Also, no one has denied that spinosaurids were not like big crocs in also
>feeding on large terrestrial animals: you just have to look at _Baryonyx_'s
>gut contents!!
>
>

As a croc specialist currently married to a theropod, I've been following
this whole Suchomimus discussion with interest.

In general, I think the comparisons between Suchomimus and gavialoids have
been exaggerated.  There are several fundamental differences, chief among
them a difference in the set of jaw muscles being emphasized.  All
long-snouted crocodyliforms reduce the pterygoideus musculature and enlarge
the temporalis assemblage.  We can see this even in extinct forms in which
the supratemporal fenestra becomes enormous.  Suchomimus, from the
publication, seems to have had relatively small supratemporal fenestrae -
granted, the squamosals are not preserved - and a fairly large antorbital
complex.

A slender snout, in crocs, reduces resistance in the water.  Whether the
pterygoideus is reduced because there is less room in the tubular rostrum,
or because there's little need for the crushing blow a gator can produce
(but a huge need for a fast temporalis snap), the result is stereotyped in
a variety of lineages independently.


chris

Christopher Brochu
Department of Geology
Field Museum of Natural History
Roosevelt Road at Lake Shore Drive
Chicago, IL 60605

312-922-9410