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Re: The Holy of Holies... Dinosauria II
don't forget the abnormally long diastema.
Kenneth Carpenter, Ph.D.
Curator of Lower Vertebrate Paleontology &
Dept. of Earth Sciences
Denver Museum of Natural History
2001 Colorado Blvd.
Denver, CO 80205
For fun: http://dino.lm.com/artists/display.php?name=Kcarpenter
>>> "Jonathan R. Wagner" <firstname.lastname@example.org> 14/Oct/04 >>>
HP Holtz wrote:
>Hadrosauridae by Horner, Weishampel & Forster (Anatotitan copei sunk into
>Edmontosaurus annectens!?! Urk!)
Yup, I just found out about this a couple months ago. The authors
suggest that the big ducks are just Edmontosaurus annectens with
dorsoventrally compressed skulls. I haven't spoken to Brett-Surman about
this yet, but I am skeptical. Our paper on postcrania addresses this issue,
and comes to the conclusion that "Anatotitan copei is [...] diagnosed by a
dramatically thin prepubic neck (9% of prepubis length), dorsoventrally
squat cranium and quadrate, and slightly elongate skull." Because sample
sizes are so small, the first character, and arguably the last as well, is
debateable. Therefore, the diagnosis rests most firmly on the short
quadrate. It is therefore no surprise that Horner et al. base their
conclusion on the suggestion that the quadrates of the relevant specimens
are crushed. I have not examined the quadrates up-close and personal, so I
cannot address this myself. However, I really look forward to seeing the
evidence that supports the suggestion that there are four quadrates on two
specimen that are all crushed by nearly the same amount! if this is the case.
Anyway, copei is probably closer to annectens than to regalis (if
the latter two are distinct species), and so "Anatotitan" is begging to be
sunk. Alternately, the wonderful epithet Anatosaurus could be resurrected
for annectens, although I personally oppose generic proliferation.