RE: Swiming spinosaurus

[GUNTER.VANACKER@ELECTRABEL.COM]

I'm convinced that you have more experience with the Baharija vertebrates
than any other listmember, so your comments on this subject are very welcome
indeed ... it seems like Spinosaurus aegyptiacus may hold more surprises
than expected and turn out to be a really specialized theropod after all.

Of course every self-respecting predatory dinosaur would snatch fish, if it
had the chance. But wouldn't a Spinosaurus be (considerably) more successful
(with its low skull and crocodile-like teeth) in actually trapping a
slippery animal like a fish. A Carcharodontosaurus, with a laterally
compressed skull would be less succesful (especially in shallow rivers) and
its allosauroid teeth were designed to tear flesh out of animals that were
often larger than the predator itself.

My perception of spinosaurids is mainly based on the descriptions of
Baryonyx walkeri, a remarkable theropod, that made us Europeans feel to be
(again) part of the leading dinosaur discovering community.


Regards,
Gunter Van Acker




Josh Smith wrote:

    We have pretty good evidence to suggest that at least _S. aegyptiacus_
(presuming there IS another valid species of this genus, which I have some
question about) spent a good deal (maybe all?) of its time wandering around
the
active shoreline. I think we go a little far with this piscivory hypothesis
(maybe quite far--where is the hard evidence that fish formed the "bulk" of
the
diet of this critter), but I don't think it is unreasonable to figure that
_S.
aegyptiacus_ may have incorporated fish into its diet.  It seems likely to
me
that a large carnivore walking around where there are fish, if it sees a
fish,
is likely to try and kill said fish.

    We also have good evidence (although I am currently unwilling to give
details about this) that reconstructing _S. aegyptiacus_ with a sail is not
unreasonable.

    I don't believe that I am going to support something done in one of
these
foolish movies, but I think that what (admittedly currently a small amount)
paleoecological data we have for this taxon suggests that it may have indeed
spent some time submerged.