RE: More on the Massospondylus embryos

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

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> Luis Rey
>
> ? ?
> I haven't seen any modern restoration of a biped prosauropod. The fact
> that they could rear and stand on their two back legs doesn't mean that
> they were habitual bipeds when walking. The long body (specially
> Massospondylus) and center of gravity never seemed to me apt to do that
> and all modern skeletal restorations show prosauropods as walking on
> all fours.
>
Galton & Upchurch (in their Prosauropoda chapter of Dinosauria II) regard 
Saturnalia and Thecodontosaurus as fully bipedal,
Riojasaurus and the other melanorosaurids (Melanorosaurus, Camelotia, 
Lessemsaurus), and the remaining prosauropods as facultative
bipeds. They quote Christian and Preuschoft in suggesting that Plateosaurus was 
a habitual quadruped which may have used a bipedal
gait for its fastest locomotion and while standing.

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

http://www.geol.umd.edu/~tholtz/
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