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RE: New Ghost Ranch Archosaur

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> Mikko K. Haaramo
> And this was published in...??
> Reference, please.

Sterling J. Nesbitt A1 A2 and Mark A. Norell A1 Extreme convergence in the body 
plans of an early suchian (Archosauria) and
ornithomimid dinosaurs (Theropoda). Proceedings: Biological Sciences. DOI: 



Living archosaurs comprise birds (dinosaurs) and crocodylians (suchians). The 
morphological diversity of birds and stem group
dinosaurs is tremendous and well-documented. Suchia, the archosaurian group 
including crocodylians, is generally considered more
conservative. Here, we report a new Late Triassic suchian archosaur with 
unusual, highly specialized features that are convergent
with ornithomimid dinosaurs. Several derived features of the skull and 
postcranial skeleton are identical to conditions in
ornithomimids. Such cases of extreme convergence in multiple regions of the 
skeleton in two distantly related vertebrate taxa are
rare. This suggests that these archosaurs show iterative patterns of 
morphological evolution. It also suggests that this group of
suchians occupied the adaptive zone that was occupied by ornithomimosaurs later 
in the Mesozoic.

                Thomas R. Holtz, Jr.
        Senior Lecturer, Vertebrate Paleontology
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
        Mailing Address:
                Building 237, Room 1117
                College Park, MD  20742

Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796