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FW: Dracorex's phylogenetic position examined with science

I am submitting the following response from Bob Sullivan on Mickey
Mortimer's criticisms. I do agree with Bob that any phylogenetic tree is
JUST a hypothesis, not fact.

        Mortimer has misrepresented my paper which primarily was
intended to be a taxonomic review (not a cladistic analysis) of
pachycephalosaurids based on my examination of the material. As far as
the phylogenetic analysis he proposes, I reject it on the grounds that
he has not personally studied the material and  is apparently just
combing the literature for characters without properly assessing them.
      The issue at hand, as I see it, is there is little compelling
evidence to produce a robust phylogenetic analysis vis-a-vis cladistic
analysis at this point in time as most of the material is too
incomplete. I find his comments regarding my work extremely offensive.
His implied assertion that cladistic methodology is the only way to do
"science" (no matter how poor the data are)is absurd. I note the
approach that he advocates only produces a "cladogram du jour" nothing
more. This is cladistic zealotry, not science. It is clear that he is
not critically assessing the data. He selectively chooses to embrace
(some) previous interpretations that result in a nice (albeit
simplistic), neatly nested, hypothetical hierarchy. He fails to
understand, in the fog of his cladistic zealotry, that cladograms are
nothing more than phylogenetic hypotheses (subject to revision as more
data are incorporated), they are not necessarilary truth (science). The
fact is that there is real disagreement over the validity of the
Marginocephalia and the interpretation that Stenopelix is a
"pachycephalosaur." His failure to recognize that the genus
Sphaerotholus is a junior synonym of Prenocephale, and Ornatotholus is
not distinct from juvenile Stegoceras, is illustrative of the cladistic
typology that he embraces. I do not find this (his approach) to be
credible science. Wishing it does not make it so and I reject his
embracement of this antiquated notion that all "flat-headed
pachycephalosaurid taxa are inherently primitive. One can manipulate the
data to effect the resulting tree. 


Dr. Robert M. Sullivan, Senior Curator
Section of Paleontology and Geology
The State Museum of Pennsylvania
300 North Street
Harrisburg, PA 17120-0024
Phone: (717) 783-9897; FAX (717) 214-2990
email: rsullivan@state.pa.us