RE: Dracorex hogwartsia

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

> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu]On Behalf Of
> Ian Paulsen
>
> HI:
>  It said in the news story about the above dino that it is a juvenile. I
> was wondering how they know it isn't a juvenile of a already described
> species?

***cough cough Stygimoloch cough cough***

or maybe Pachycephalosaurus itself.

I need to read the paper to see the justification for it, but I know that some 
pachycephalosaur experts who've seen this and similar
specimens have opined that these may be juveniles of one or the other 
previously known long-snouted Lancian pachycephalosaurs.

Sample size is not particular good for any of these, so we face the spectres of 
ontogeny and sexual dimorphism as well as actual
taxonomic differences.

A new genus & species isn't crazy. But neither is ontogeny.

                Thomas R. Holtz, Jr.
        Senior Lecturer, Vertebrate Paleontology
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
        Mailing Address:
                Building 237, Room 1117
                College Park, MD  20742

http://www.geol.umd.edu/~tholtz/
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Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796 all the way!"