Re: Definition of Dinosauria (was: underlying basis of classification)

["T. Mike Keesey" <tkeese1@gl.umbc.edu>]

On Tue, 13 Jul 1999 zenlizard@juno.com wrote:

> On Tue, 13 Jul 1999 09:10:55 -0600 chris brochu  writes:
> >  Dinosauria is the last common ancestor of ornithischians and
> saurischians and all >of its descendents.  
> 
> Oh, ack.  I thought Dinosauria was _Triceratops_  and all animals closer
> to _Triceratops_  than to either  (_Aves_)  or  (_Avialae_)  (depending
> on who's doing the definition).  Was this latter definition discarded?

That definition was never used. That's pretty close to the definition of
Ornithischia, though.

Dinosauria is the most recent common ancestor of _Triceratops_ and modern
birds, plus all of its descendants.

--T. Michael Keesey
tkeese1@gl.umbc.edu | THE DINOSAURICON: http://dinosaur.umbc.edu/
AOL IM:   RicBlayze | WORLDS:    http://www.gl.umbc.edu/~tkeese1/