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Re: bulldog tyrranosaurs



> As for the gracile/robust morph deal, why is this so important?  If you look
> around at different people, wolves, cats (of all species), fish, etc., you
> see size variation within a species.

    I can't speak for species or genus distinction, but if you are
referring to sexual dimorphism, the "robust" and "gracile" morphs seen is
Coelophysis, Syntarsus, and apparantly Tyrannosaurus as well, are not
totally random variations in size or morphology across the population.
There are two distinct size classes, and particular suites of
morphological characteristics which characterize the size classes.  The
dimorphism in T.rex is still fairly controversial (being a smaller smale
size), but there is less doubt about it in the Ghost Ranch theropods. 
Check out the papers on these three theropod genera in "Dinosaur
Systematics". 
      Has anyone confirmed Pete Larson's claim about the size and
placement of the first caudal chevron?  Has anyone even bothered to look
for this feature in other theropods?

LN Jeff
O-