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Re: David's Statements [Extended Version]
Jaime Headden wrote-
> I stand corrected, my statements were more general. Am fairly
> certain most of my statements were based on *Sinornithosaurus*
> and *Gallimimus* (which don't seem to have very many pneumatic
> dorsals, but cervicodorsals or dorsosacrals do seem to be
> pneumatic. Am also very certain that *Pelecanimimus* is more
> pneumatic than most, and that ornithomimids are a reversal on
> the tree, but must jump back into the lit. Am also curious is
> anyone has Xabier Perez-Moreno's email, if he has one?
Gallimimus seems to have pleurocoels on its cervical and first two dorsal
vertebrae. Russell (1972) states Struthiomimus, Ornithomimus and
Dromiceiomimus lack pleurocoels on all presacrals except possibly anterior
cervicals. No pleurocoels are shown or mentioned in Smith and Galton's
(1990) redescription of Archaeornithomimus and Pelecanimimus is stated to
lack presacral pleurocoels. Garudimimus is also described as lacking
pleurocoels on its "spinal and sacral" vertebrae. As Pelecanimimus is
stated to lack presacral pleurocoels, I'm interested how you reached the
conclusion it is more pneumatic than other ornithomimosaurs (although I do
agree the lack of pleurocoels in these genera is a reversal). As for
Sinornithosaurus, the dorsals are nearly all disarticulated and undescribed.
The authors code Sinornithosaurus "?" for their "dorsal pleurocoels present"
character, so I don't think conclusions regarding it can be made at this
Perez-Moreno has posted on the list in the past from- NINO@vm1.sdi.uam.es .
> I distrust polypositional taxa, where the newest phylogeny
> drops these certain taxa in this brand new place, and _whomp!_
> you get a new theory.
So do I. Which means I distrust a LOT of theropods. There's Nqwebasaurus,
compsognathids, Protarchaeopteryx, Microraptor, Rahonavis, Unenlagia,
troodontids, Avimimus, etc. Probably a good half of my OTU's. :-)