re: Wilson and Sereno

[tidwell@ix.netcom.com]

Re: Dan Varner:
 comments on the skeletal drawings in Wilson and Sereno vs. Greg Paul's 
Camarasaurus point up some significant differences.  My first thoughts were 
that Wilson and Sereno must have used data from Camarasaurus supremus for 
their drawings, as this species is much more robust than the other species 
of Camarasaurus. But all of the illustrations in the new monograph are of 
C. grandis, including the vertebra on page 59 which is mislabeled C. 
supremus from Osborn and Mook.  This vert. is actually found on page 111 of 
Ostrom and McIntosh's Marsh's Dinosaurs, where it is labeled C grandis.

Perhaps the key to the differences in skeletal drawings lies in the 
question of just how closely does Camarasaurus resemble Apatosaurus...
Jack McIntosh has always said that the two are quite similar in several 
areas; particularly in the robust nature of the hind legs . The mid and 
posterior caudal verts are almost identical as well. For many years various 
skeletal elements of Camarasaurus (Marsh's Morosaurus) and Apatosaurus were 
confused with each other. So skeletal drawings of the two taxa should 
resemble each other, and indeed the Apatosaurus and Camarasaurus in Wilson 
and Sereno are remarkable alike. 
Although I find Greg's drawings of a gracile Camarasaurus more pleasing to 
the eye, I suspect that the Wilson and Sereno drawings may be somewhat more 
in line with the overall robustness of the genera.

With sauropods, as in many other areas of life, Size Counts.

Virginia Tidwell