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I recently completed a whirlwind five-day tour of Utahn theropods, and all
I can say is, man. University of Utah is reclaiming their Cleveland-Llloyd
dinosaurs from BYU. I believe that there will be a lot of reprepping on
this stuff and a lot of volunteers and students are being trained right
now, recataloging is going on and support jackets are going to be made up
for the collections. New field work is planned for locations in Utah AND
they are going to reopen the Cleveland-Lloyd Dinosaur Quarry(!). As much
as it produced, it never actually played out. Very exciting. Ceratosaurus
dentisulcatus is one kickass big, cool theropod. Supposedly Ceratosauria
lack paired posterior processes on the chevron bases but C. dentisulcatus
unquestionably had them. The excavation of the proximal end of the fibula
is quite incredible as well, so this is not a definitive coelurosaur
character. Nice femur and tibiotarsi. CLDQ has some other interesting
things- various weird bones like tibiae, vertebrae, ischia that just don't
fit anything known so they are variously thought to be from Stokesosaurus,
Marshosaurus, or Coelurus and I think there may be some Ornitholestes
stuff in there too... Lots of small Maniraptora manual unguals.
        Western Paleo's juvenile Ceratosaurus is just remarkable. What's
amazing, other than the completeness of the specimen, is that a lot of the
fusions that take place in later life in Ceratosaurus (pretty much
anything that can fuse, does, like in abelisaurs) aren't there so you can
make out lots of skull bones and whatnot before their sutures are
obliterated. As Chure has described, there is this huge, weird peg that
nocks into a socket on the pubis.
        Then off to Brigham Young University. They have a lot of cool
dinosaur mounts for such a small museum, but the really cool stuff is
behind the scenes- stacks and stacks of stuff, lots from the Dry Mesa
Quarry. Their Allosaurus material seems just huge to me. But
Torvosaurus... Torvosaurus is one bad-ass dinosaur. I think it looks way
cooler than T. rex. T. rex looks sort of birdy and intelligent with that
big head and long legs. Torvosaurus just looks like it was designed to
kick butt;like it's got no brains, no speed, no frills, like it'd just
stomp up and open up a 6-ton can of whup-ass. To paraphrase the Incredible
Hulk, "Torvosaurus SMASH!" It has an incredibly massive dentary with
monstrous alveoli. As for the forelimbs... in the eloquent words of Keanu
Reeves, "Uh, whoa." Looks like it could do curls with volkswagens or
something. Learned relatively little new there since it has been
well-illustrated by Jensen and then Britt. There is decent Ceratosaurus
material out of the Dry Mesa quarry as well, I believe the ischia have
been illustrated in Britt's paper on that stuff but wasn't IDed, also a
cool femur of the robust form, also a gracile one. I think I have finally
figured out the homology of all those stupid trochanters after seeing so
many Ceratosaurus femora. There are so many trochanters mixed up with each
other that we will probably have to rename everything in a consistent and
logical fashion. And then there is ANOTHER Ceratosaurus; it was dug up
years ago and is an associated specimen (unlike the mixed-up bones from
the Dry Mesa bonebed) with a full skull, lots of pelvic stuff, some verts.
To quote Cartman: kickass. It has an aesthetically pleasing oxide-reddened
tint to the bones, rather than the usual Morrison jet black or Dry Mesa
grey.
        So that was pretty cool. It was on the one hand exhilarating to
see so much stuff and see so much information, but it also hurts when it
knocks holes in nyour nice, neat little theories and reveals how much you
have to learn... even with the real bone in front of you there is so much
left to learn. I feel like 90% of what I learned on that trip is what
shelf everything was on. Listen: you've GOT TO SEE THE REAL STUFF. Papers
aren't useless or we wouldn't publish them, but it's vitally, crucially,
monstrously important to see the real stuff, in person, free of prejudice
and with an open mind and a keen sense of your own ignorance so that you
can be ready to find something out... Real material. Get rid of all those
interpretations- illustrations and descriptions- placed between you and
the real things. The literature makes it out as so much more simple and
clean-cut than it is. I must have looked at roughly a dozen Allosaurus
femora to find one little nutrient foramen on just two of them so as to
convince myself that it was honestly, really there... for some reason the
bones like to crush through that region.  The literature erases those
kinds of complexities much of the time. And there are real limits to what
you can learn from a publication, even ones like Madsen's wonderful
monographs. I bought my Allosaurus monograph about a year ago and have
just about broken the spine but still I learned so much from seeing actual
bone that the illustrations simply could not capture. I can't believe I
actually thought I had a clue about dinosaurian palates before sitting
down with that juvenile Ceratosaurus skull and trying to ID the various
bones and rearrange them in the correct order. There is no better way to
understand what makes an Allosaurus tarsal different from a Torvosaurus
astragalus than to put them side by side. And once you've done that, you
will never confuse an Allosaurus calcaneum or astragalus with the element
from Torvosaurus ever again.
        Oh yeah, and a few weeks back I caught The Great Russian
Dinosaurs. It's a spendy exhibit (18$ admission I think) but stop by and
support our comrades (who I assume are getting a cut of this) and see some
really neat stuff, including an Avimimus that shows some startlingly
oviraptorosaur-like features... as well as features that are clearly too
primitive to be oviraptorosaur. (Juvenile oviraptorid skull? not with that
articular it isn't...) A couple of the cervical centra seem to show double
pneumatopores, on one side... the pubic boot is well-preserved and
shortened posteriorly like in oviraptorosaurs. Nifty...
        
        Been looking over the allosaur stuff a bit. I haven't seen the
specimens other than a few Acrocanthosaurus bits, but I'm not too
comfortable with the existing arrangements. Sinraptor actually seems to
show a fair amount of similarities to Carcharodontosaurus and
Acrocanthosaurus. All three have a similarly huge postorbital rugosity. In
Sinraptor the postorbital approaches the lacrimal/prefrontal and it
contacts them in Carcharodontosaurus and Acrocanthosaurus. In Sinraptor
and in Acrocanthosaurus, the prefrontal is expanded and excludes or
virtually excludes the frontal from the orbit. This is probably what was
going on in Carcharodontosaurus but it's hard to tell since the prefrontal
and lacrimal seem to be fused. So based on this and some other stuff I'd
guess:


         +-Allosaurus
---------+
         +             +------Sinraptor
         +-------------+
                       +     +------Carcharodontosaurus
                       +-----+
                             +------Acrocanthosaurus
                
Incidentally, something I've been suspecting for a while is that the
"prefrontal absent" and "T-shaped lacrimal" characters for dromaeosaurs
and troodontids may be the same thing. The prefrontal may simply have
fused onto the lacrimal, making it sort of T-shaped.

On the Ceratosauria problem.... man. This is not simple at all. I was
thinking that after seeing three separate Ceratosaurus skeletons besides
the type and sundry disarticulated Dry Mesa elements I might actually have
a clue about how they fit into theropod evolution, but I don't. I'm going
to have to see some good coelophysoid material...

-n