[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

RE: Major new paper on dromaeosaurids, with other significant maniraptoran info

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> Tim Williams
> Thomas R. Holtz, Jr. wrote:
> >Senter, P., Barsold R., B.B. Britt & D.A. Burnham. 2004. Systematics and
> >evolution of Dromaeosauridae (Dinosauria, Theropoda). Bulletin
> of the Gunma
> >Museum of Natural History 8: 1-20.
> Where do the therizinosaurs end up?

Not included: I showed all the main OTUs (they ran versions with fragmentary
"dromaeosaurid" taxa to see where they wound up, too).

> >Troodontids come out as bullatosaurian arctometatarsalians.  Whoa, now
> >that's something I haven't seen for years...
> If troodontids are put back in the Bullatosauria, and outside of the
> Maniraptora, then the propubic pelvis of troodontids represents a
> retention
> of the primitive condition, and not a secondary reversal (which
> is required
> if troodontid is a maniraptoran).

True, if (as they contend) Sinovenator is not a troodontid.  For what it is
worth, I've incorporated some of their changes (but not all their new
characters yet) into my matrix, and Sinovenator still falls out as the
basalmost troodontid, and troodontids are eumaniraptorans.

>  Oviraptorosaurs, therizinosaurs,
> dromaeosaurs and birds all have an opisthopubic pelvis.

Most oviraptorosaurs are propubic, or at least mesopubic, so reversals are
necessary here.

> The irony is that within the clade Maniraptora (which means "raptorial
> hands"), only the dromaeosaurids appear to have used their hands to catch
> prey.  Basal oviraptorosaurs and therizinosaurs were probably
> herbivorous,
> and I doubt that microraptorians and basal birds used their wings
> to catch
> prey for fear of damaging the wing feathers.

I don't know about that, particularly if these critters went after very
small prey (lizards and the like). Wing feathers can take a fair amount (not
huge amount, but fair) of punishment in at least some living birds. And if
they were used more for non-aerial locomotion (e.g., WAIR) they could
concievably be even more beaten up from time to time.

                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