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Re: SVP DINORESPIRATION



At 07:42 AM 10/17/97 -0400, Michael wrote:

>Three questions:
>     1.  When did gastralia begin to develop in the tridatcyl theropods?
>      2.  Did they develop in conjunction with the expansion of the rib cage
>or did one follow the other?

Your question has the wrong polarity.  Gastralia are a VERY old feature:
most primitive amniotes have them.  The reason non-ornithurine theropods had
gastralia was that they had not lost them yet.

Thomas R. Holtz, Jr.
Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
Dept. of Geology              Email:th81@umail.umd.edu
University of Maryland        Phone:301-405-4084
College Park, MD  20742       Fax:  301-314-9661