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RE: Two "new" papers and a query for Thomas Holtz

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> Stephan Pickering
> I believe some dromaeosaurs could fly/glide, with
> variable modifications of the arms and hands, and this
> does not make them non-theropods (after all, Aves is a
> converted clade name within Theropoda)...and I believe
> some theropods could climb/run up a tree and come back
> down (cf. Ken Dial, the hoatzin, et al.).Thus, their
> comments that most paleontologists believe theropods
> to be "strictly terrestrial" is puzzling: there are
> theropods in the air, on the ground, even preferring
> aquatic habitats.

Quite so!!  As I stated in my review, the Czerkas et al. papers suffer from
a very typological mode of systematics rather than a phylogenetic one (a
similar problem suffered by some of the "BAND" papers, viz. the idea that
the braincase of Coelophysis isn't like a bird's, therefor theropods can't
be bird ancestors...).

> In GAIA # 15, you elaborate a data matrix. Have you
> yet examined each of the Czerkas taxa, ascertained
> their characters, and "fed" them into your data
> matrix?
> If so, would you post these, using GAIA as a template
> (i.e., rather than recapitulating all of the analyses
> of GAIA, you could present the characters of each
> taxon, referring the reader to the applicable GAIA pages).

Actually, I have not yet done so, but certainly intend to add these critters
to my latest matrix.  However, my latest matrix is greatly expanded in terms
of the number of characters (and mostly conducted at the "genus/species"
level rather than more inclusive OTUs), so that I really wouldn't feel that
"going backwards" to the Gaia matrix is the right step.  That being said, I
know that at least one person on this list has already done the test you
suggested, and perhaps they can post their results.

                Thomas R. Holtz, Jr.
                Vertebrate Paleontologist
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
                College Park, MD  20742
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796