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RE: Deinonychus

Great, thanks for the notes.

I'd like to revisit the posterior mandible, it represents mainly Ostrom's 
figures, but his specimen was incomplete and he probably figured the emf too 
big. that's one nice thing about skeletons, you can put in replacement parts.

I'll take  a look at the humerus again, this was from 2005, after all!

I know you figured a very deep snout in D o'A, and I know you looked at 
Witmer's material, as did I, but I am still skeptical. Are you saying that YPM 
5232 is not trustworthy? Because that right maxilla and nasal just don't seem 
so deep.

Thanks again, good feedback.
From: owner-DINOSAUR@usc.edu [owner-DINOSAUR@usc.edu] on behalf of 
GSP1954@aol.com [GSP1954@aol.com]
Sent: Tuesday, August 06, 2013 8:58 PM
To: dinosaur@usc.edu
Subject: RE: Deinonychus

The neo skeleton is better than past efforts but there are issues.

The skull is fairly OK, and correct in having a long snout (should be a
little longer), but no one other than an elite few including myself (it's not
my fault) have a correct restoration based on the virtually complete skull
material. The skull is too small relative to the postcrania, making the snout
longer might correct that. The posterior mandible is very wrong.

The AMNH material is from much lower in the Cloverly and is hardly likely
to be D. a., may well be another genus or even subfamily. That eliminates
most of the pectoral girdle, pelvis and hindlimb except for the feet (I
illustrated what can be attributed to D. a. in the field guide). So we don't 
know how retroverted the pubis was if any (one reason did not do a side view
life restoration in the field guide). The pelvis, femur & tibia look rather
large for the rest of the skeleton.

It looks like the humeri are flipped along their long axes about 180
degrees from what they should be so that the deltopectoral crest projects
ventrally when the arms are folded. In birds the humerus does an odd rotation so
that the crest is directed dorsally, and the ventral surface
the distal condyles face strongly laterally. Dinobird humeri folded posture
may have been less extreme but was doing something like that.