Re: Basal Theropod Arm Position

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

My thoughts, with no real serious way to choose between them:

* Swept back, croc-like.

*Held forward.

*Tucked as close in to the body as possible

On Sun, September 18, 2011 5:56 pm, Harris, Jerald wrote:
> A hypothetical question for y'all: in what position, d'you think, would a
> basal theropod, such as a coelophysoid, hold its arms while swimming?
> Given the absence of the bird-like wing-folding ability at all joints, and
> given the relatively limited flexibility at the shoulders and elbows
> described by Carpenter (2002), what's the alternative in order to prevent
> the arms from acting as baffles and maximize hydrodynamicity?  Would they
> be kept swept backward, croc-like?  Even if Carpenter's limits are off,
> which I might expect based on the more recent works that have shown that
> dinosaurs probably had great, heaping gobs o' cartilage at the joints,
> which likely enhanced mobility, I still don't see coelophysoids having
> anything close to a wing-like folding ability...
>
> Carpenter, K. 2002. Forelimb biomechanics of nonavian theropod dinosaurs
> in predation; pp. 59?76 in Gudo, M., Gutmann, M., and Scholz, J. (eds.),
> Concepts of Functional, Engineering and Constructional Morphology.
> Senckenbergiana Lethaea 82. E. Schweizerbart'sche Verlagsbuchhandlung,
> Frankfurt.
>
> --
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Dr. Jerry D. Harris
> Director of Paleontology
> Dixie State College
> Science Building
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>
>
> "Normal" is just a setting on the
> washing machine.
>
>                          -- Bernice Lewis
>


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
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