Re: Two legs good, four legs better?

[Jura <pristichampsus@yahoo.com>]

--- On Wed, 9/17/08, Allen Hazen <allenph@unimelb.edu.au> wrote:

> -----> So, what are the latest mass estimates for a
> large Phobosuchus (or
> other really big Mesozoic croc) and how do they compare to
> those for
> top-of-the-line theropods?  I know, crocs cheat by being
> amphibious, but
> even so the Mesozoic macro-herbivore had quadrupedal
> carnivores to worry
> about!
> 
> Allen Hazen

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Schwimmer (2002) estimated a conservative weight for western populations of 
_Deinosuchus_ at 8.5 tonnes. That would make it about a tonne, or so heavier 
than _Tyrannosaurus rex_. _Sarcosuchus_ appears to scale to approximately 
_Deinosuchus_ proportions as well, while _Purussaurus_ comes in at an estimated 
weight closer to 10 tonnes. 

Though crocs cheat somewhat by being semi-aquatic, they are only semi. Part of 
their time is spent on land, and Schwimmer was able to determine that 
_Deinosuchus_, at least, could have still walked erect on land. Though it 
probably wasn't doing much hunting this way.

Jason

Schwimmer, D. 2002. King of the Crocodylians: The Paleobiology of 
_Deinosuchus_. Indiana U Press. ISBN: 0-253-34087-X