RE: Greg Paul's new (or newly named) iguanodonts

["Thomas R. Holtz, Jr." <tholtz@umd.edu>]

> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu] 
> On Behalf Of Tim Williams
>
> Tom Holtz wrote:
> 
> > The original work of Gauthier, Clark & Benton, Parrish, & 
> colleagues 
> > back in the 1980s was really to sort out this mess, and 
> resolve that 
> > classic archosaurs fell into three clusters: dinosaurs, pterosaurs, 
> > and their kin; primitive guys (the traditional "proterosuchians" as 
> > well as Euparkeria and Proterochampsidae); and the 
> croc-ankle cluster.
> 
> There was a fourth category (not so much a 'cluster'), which 
> might  be called "WTF".  Things like _Longisquama_ and 
> _Sharovipteryx_ (_Podopteryx_) ended up here.  :-)

But that really only existed in the "anti-dinosaurian origin of birds"
community (okay, and the Russians). It wasn't part of the normal discourse
of Thecodontia.

> > 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!!
> 
> Except for maybe _Scleromochlus_ (which has popped up as a 
> prospective'pro-avian' once or twice).  But yes, I know 
> exactly what you mean.  

Okay, and _Lagosuchus_. But really, once you start arguing for origins
within Ornithodira, you really aren't terribly far off of the dinosaurian
origin hypothesis... :-)

[snip]
> 
> > (This is opposed to the Heilmann model, which did derive 
> birds out of 
> > Euparkeria-like forms).
> 
> I think he might have put _Ornithosuchus_ there too.  Not 
> 100% sure though.

Yes, indeed.

Thomas R. Holtz, Jr.
Email: tholtz@umd.edu   Phone: 301-405-4084
Office: Centreville 1216                        
Senior Lecturer, Vertebrate Paleontology
Dept. of Geology, University of Maryland
http://www.geol.umd.edu/~tholtz/
Fax: 301-314-9661               

Faculty Director, Earth, Life & Time Program, College Park Scholars
http://www.geol.umd.edu/~jmerck/eltsite/
Fax: 301-405-0796

Mailing Address:        Thomas R. Holtz, Jr.
                        Department of Geology
                        Building 237, Room 1117
                        University of Maryland
                        College Park, MD 20742 USA