Re: Pre-archosaur...was : What came before Eoraptor?

["T. Mike Keesey" <tmk@dinosauricon.com>]

I have a couple of cladograms at
<http://dinosauricon.com/taxa/archosauromorpha.html>.

The first is an attempt at a general consensus. The second is based on the
more heterodox one at Dave Peters' site.

Note that, under phylogenetic taxonomy, dinosaurs could not have evolved
from prolacertiforms unless a) dinosaurs *are* prolacertiforms, or
b) "Prolacertiformes" is a paraphyletic assemblage (which, I think, has
been proposed).

Phylogeny is usually more about finding sister groups than actual
ancestors, due to the paucity of the fossil record.

-- T. Michael Keesey .................................. <tmk@dinosauricon.com>
   My Worlds (including The Dinosauricon) ... <http://dinosauricon.com/keesey>
   AOL Instant Messenger ........................................ <Ric Blayze>