RE: New Deinocheirus specimens found, indicating basal ornithomimosaur

["Thomas R. Holtz, Jr." <tholtz@umd.edu>]

Something we need to consider is if the attachment scars and crests are 
disproportionately big, or simply the product of allometry
on a standard-model ornithomimosaur humerus. Comparison of the humeri of 
Therizinosaurus and Deinocheirus show that the former is
the real powerhouse of the two.

Thomas R. Holtz, Jr.
Email: tholtz@umd.edu   Phone: 301-405-4084
Office: Centreville 1216                        
Senior Lecturer, Vertebrate Paleontology
Dept. of Geology, University of Maryland
http://www.geol.umd.edu/~tholtz/
Fax: 301-314-9661               

Faculty Director, Science & Global Change Program, College Park Scholars
http://www.geol.umd.edu/sgc
Fax: 301-314-9843

Mailing Address:        Thomas R. Holtz, Jr.
                        Department of Geology
                        Building 237, Room 1117
                        University of Maryland
                        College Park, MD 20742 USA

> -----Original Message-----
> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu] On Behalf Of 
> evelyn sobielski
> Sent: Wednesday, November 06, 2013 11:04 AM
> To: dinosaur@usc.edu
> Subject: RE: New Deinocheirus specimens found, indicating basal 
> ornithomimosaur
> 
> Would the claws (and arm muscles) be suitable to uprooting and breaking open 
> cycad trunks or similar plants? IIRC the tricipital
> attachment scar should be large and quite rugose in such a case. The claws at 
> least of advanced therizinosaurs don't seem well
suited
> for such foraging activity (too long and compressed, better for shearing off 
> foliage), and as regards non-dinosaurian competitors
in
> such a niche there were few if any at that time.
> 
> 
> Regards,
> 
> Eike
> 
> 
> 
> 
> --------------------------------------------
> Thomas R. Holtz, Jr. <tholtz@umd.edu> schrieb am Mi, 6.11.2013:
> 
>  Betreff: RE: New Deinocheirus specimens found, indicating basal 
> ornithomimosaur
>  An: qi_leong@hotmail.com, "'Tim Williams'" <tijawi@gmail.com>, "'Dinosaur 
> Mailing List'" <dinosaur@usc.edu>
>  Datum: Mittwoch, 6. November, 2013 15:38 Uhr
> 
>  The manual claws of Deinocherius are
>  most definitely NOT raptorial! However, I understand when  just viewing them 
> from a distance  they might appear so. Handling the
> actual specimens (or  casts), you find they are much thicker, much less 
> pointed,  and so forth than  people commonly think: more
like
> the claws of basal  therizinosauroids.
> 
>  Torvosaurus, Suchomimus, megaraptorans, etc., are much  better models for 
> what a giant raptorial claw actually looks
>  like: far more
>  tapered, far more pointed, more elongate compared to the  articular facet, 
> etc.
> 
>  Thomas R. Holtz, Jr.
>  Email: tholtz@umd.edu
>  Phone: 301-405-4084
>  Office: Centreville 1216
> 
>  Senior Lecturer, Vertebrate Paleontology  Dept. of Geology, University of 
> Maryland  http://www.geol.umd.edu/~tholtz/
>  Fax: 301-314-9661
> 
>  Faculty Director, Science & Global Change Program,  College Park Scholars  
> http://www.geol.umd.edu/sgc
>  Fax: 301-314-9843
> 
>  Mailing Address:    Thomas R. Holtz, Jr.
> 
>  Department of Geology
> 
>  Building 237, Room 1117
> 
>  University of Maryland
> 
>  College Park, MD 20742 USA