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RE: Stormbergia dangershoeki, new Early Jurassic ornithischian from South Africa
> From: firstname.lastname@example.org [mailto:email@example.com]On Behalf Of
> T. Michael Keesey
> > Here's my problem with the current stem-based definition of Ornithopoda...
> > What if current euornithopodan taxa ("hypsilophodontids", iguanodontians)
> > form a paraphyletic array between heterodontosaurids and marginocephalians.
> > If you look at Fig. 25 of Butler (2005), this would not require a major
> > shift in topology.
> Yes, but that's a ... septachotomy? The lack of resolution there
> indicates he was not looking closely at relationships within that
Actually, we don't know that it is...
One thing that I would REALLY like to see more researchers do is show consensus
trees (or subtrees) other than strict and majority rule. I haven't had time to
strip out the data and run it myself, so I don't know what the precise details
of the topology that was recovered. It might well be that everything but
Jeholosaurus is stable, but the latter is popping out as as the sister taxon to
each of the "hypsilophodonts", as the sister to Iguanodontia, as the sister
group to Marginocephalia, and as the sister to Cerapoda as a whole. The strict
consensus would indeed be the heptachotomy shown.
Still, this is one damned important paper, and part of a series of damned
important papers that will help sort out the mess of little bipedal
ornithischians. Honestly, the cladogram he found makes a heck of a lot of sense.
Thomas R. Holtz, Jr.
Senior Lecturer, Vertebrate Paleontology
Department of Geology Director, Earth, Life & Time Program
University of Maryland College Park Scholars
Building 237, Room 1117
College Park, MD 20742
Phone: 301-405-4084 Email: firstname.lastname@example.org
Fax (Geol): 301-314-9661 Fax (CPS-ELT): 301-405-0796