Re: Broader than Dinosauria

["Ken Kinman" <kinman@hotmail.com>]

Jaime,
    It will take some time for me to fully digest all that anatomical 
detail, but it seems that your concept of a "fully" open acetabulum is a 
little more inclusive than what is generally meant by "fully".  But I agree 
that it is good to look at this closely and get the semantics out of the 
way.
    You regard herrerasaurs and Campsosaurus as fully open, but you didn't 
mention Guaibasaurus or Saturnalia in that context.  Do you regard their 
acetabula as fully open?  If Guaibasaurus (which apparently split off 
between herrerasaurs and Campsosaurus) is only partially open, would you 
regard that as a partial reversal back toward a more primitive state.
                 ----Ken

P.S.  I don't doubt the ornithischian nature of Pisanosaurus, but like 
George, I think we have taken Sereno's basal placement of this genus for 
granted.  I have no great confidence in *any* basal topology of the 
ornithischians, and am looking forward to more on that from George and 
others in the future.

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