Re: oldest dino fossils location?

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

B tH wrote:
> At the current time, are the very oldest dinosaur fossils from South
> America?

Yes, but there are Indian fossils that might be of comparable (earliest
Carnian) age.

> Does anyone expect older ones to be found elsewhere? (speculation, of
> course)

Yes: see above

> Could S.A. be the radiating point from which they spread to the rest of
> the super-continent?

Possible (they had to start somewhere), but since the Ischigualasto and
Santa Maria fossils contain both saurischians and ornithischians, the
concestor of all dinosaurs had to be earlier in time.

In any case, the fossil record is spotty enough that the South American
samples of earliest Carnian material may have more to do with where we
happen to have fossiliferous exposures and less to do with the actual
distribution of taxa in the past.

-- 
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, Earth, Life & Time Program, College Park Scholars
http://www.geol.umd.edu/~jmerck/eltsite/
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