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Re: Phyl tax misunderstandings - oops!

On Sat, 15 Nov 1997, Ronald Orenstein wrote:

> By Feduccia's hypothesis I assume that his "Maniraptoria" would contain no
> dinosaurs at all, since all of the dinosaurs would by his view share a more
> recent common ancestor with Ornithomimidae than with birds.
> I must stop writing messages after midnight.....

Well actually if Fedduccia is right (I am assuming that he advocates bird
origins from within or near the crocodylomorpha) Maniraptora would contain
(but not taxa we are used to calling dinosaurs) since Dinosauria by
definition includes modern birds (it is a node
based taxon connecting Triceratops with Modern Birds). Therefore
would include the traditional dinosaurs, pterosaurs, popsaurids,
ornithosuchids, aetosaurs, phytosaurs, crocodylians etc.. Maniraptora
would be synonymous with a number of taxa such as Saurischia, Theropoda,
Tetanurae, wich are all stem based taxa defined as everything closer to
modern birds than to a variety of tradition dinosaurs. All traditional
non-avian dinosaurs (Dromaeosaurids included) would be placed in the
Ornithischia (everything closer to Triceratops than to modern birds).
Furthermore the Archosauria (crocs+birds) would become a less inclusive
clade within the
Dinosauria. These are just some of the fun and games you can have with
phylogenetic taxonomy and large scale changes in phylogenetic hypotheses.
It is also good reason to use Georges definition of Dinosauria
(Megalosaurus +Iguanodon), which would keep the Dinosauria pretty much as 
we are used to it (with the birds position inside or outside of it
debatable). Not that it really matters in this case though, I don't think
there is much chance that Fedducia is right.

Adam Yates