Re: FAQ: Dinosaur Classification Overview

[AM Yates <Adam.Yates@bristol.ac.uk>]

On Thu, 8 Feb 2001, David Marjanovic wrote:

> > You could [...] perhaps also mention that some workers believe
> herrerasaurs
> > are actually sister group to all other dinosaurs (not just to theropods).
> 
> In which case they aren't dinosaurs at all, because dinosaurs are defined
> node-basedly. BTW, this opinion seems to have become quite rare in the last
> few years. For example, it has turned out that 2 sacral vertebrae, not 3,
> are plesiomorphic for dinosaurs.


Expect a resurgence in the future, I know of a few analyses that
are in preparation or review at the moment, that find Herrerasaurs
aren't theropods, saurischian dinosaurs, yes but not theropods. 

cheers

Adam Yates