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Re: New Deinocheirus specimens found, indicating basal ornithomimosaur



Are either of those animals capable of significant cranial excursion of the 
shoulder (i.e. Flexion)? Most theropods weren't, after all (so many images of 
poor theropods dislocating their arms to grab prey...) That might help 
constrain functional hypotheses.

--Mike H.

Sent from my Cybernetic Symbiote

> On Nov 6, 2013, at 8:10 AM, "Thomas R. Holtz, Jr." <tholtz@umd.edu> wrote:
> 
> 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
>