[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
RE: Greg Paul's new (or newly named) iguanodonts
> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu]
> On Behalf Of David Marjanovic
> > And really: those who have argued for a "thecodont" origin
> since the
> > 1970s (Tarsitano, Martin, etc.) argued for relationships
> with animals
> > that thecodont workers (Charig, Parrish, Chatterjee) would not
> > consider thecodonts at all!!
> Considering avicephalans "thecodonts" was made possible by
> the absence of tree-thinking. In precladistic times, all but
> maybe the real specialists on any group didn't imagine a
> group as a twig, they imagined it as a blob on a romerogram.
> Such blobs lack internal structure; the fact that no
> avicephalan fits into the "thecodont" tree didn't matter
> because people simply didn't think of it. At best, blobs on a
> romerogram consist of more blobs with stippled lines between
> them; adding one more little blob for *Megalancosaurus*,
> supported on a stippled line that originates from a
> free-floating question mark, is no big affair (if only you
> believe that
> *Megalancosaurus* has The Defining Feature, the antorbital fenestra).
While I agree with much of what you said, in actual fact the avicephalan
types were only considered thecodonts by the "anti-dinosaurian origin of
birds" folks. You didn't see them mentioned in the works of those who
actually dealt with the thecodont blob (to which I should add the
Colbert, and Benton!!)
Thomas R. Holtz, Jr.
Email: email@example.com Phone: 301-405-4084
Office: Centreville 1216
Senior Lecturer, Vertebrate Paleontology
Dept. of Geology, University of Maryland
Faculty Director, Earth, Life & Time Program, College Park Scholars
Mailing Address: Thomas R. Holtz, Jr.
Department of Geology
Building 237, Room 1117
University of Maryland
College Park, MD 20742 USA