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RE: FW: Dracorex's phylogenetic position examined with science

Bob Sullivan wrote-

        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.

As Tim pointed out, your paper did make phylogenetic claims, regardless of its primary purpose. It and the Dracorex papers both had sections dedicated to phylogenetic implications. I want to point out that I agree not every paper needs a cladistic analysis. This was not my problem with Sullivan's or Bakker et al.'s papers.

It's true I didn't examine any material firsthand. The characters were just those of Williamson and Carr (2002) though. Like I said, the point was not to test your ideas regarding Prenocephale or the sister group to pachycephalosaurins vs. theirs. I didn't include your characters, so that couldn't be tested. The point was that the homoplasic Dracorex is not the problem for cladistics it was presented as, nor does its combination of characters mean we should start questioning the standard results of pachycephalosaur phylogenetic analyses. In fact, by putting Dracorex into a previously made analysis, I tested this even better than if I had used my knowledge of Dracorex when creating a novel matrix. Williamson and Carr's matrix was 'unprepared' for Dracorex, in a way, yet it still handled the taxon just fine.

      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).

Where to begin... It's true people haven't utilized much data yet when it comes to determining pachycephalosaur phylogeny. But this doesn't mean we shouldn't try with what we have. Maybe the data really are too poor at the moment, but at least a cladistic analysis gives us something tangible and somewhat objective that can be tested against additional data. I don't view the result of any cladistic analysis as 'the truth', since I am well aware of how labile they are (depending on which taxa, characters, states, etc. are included). They are merely the best hypotheses available, given currently utilized data. And this is what science is. Science is not truth (which we may never know).

fact is that there is real disagreement over the validity of the
Marginocephalia and the interpretation that Stenopelix is a

I haven't seen such disagreement in the literature.
Marginocephalia seems to only get stronger, especially with the discovery of Yinlong. The latter ironically lacks a parietal shelf, suggesting you may be right (albeit for the wrong reason) in claiming this was convergent in derived ceratopsians and pachycephalosaurs. However, its mosaic of pachycephalosaur and ceratopsian features makes this irrelevent.
As for Stenopelix, every recent analysis I've seen has placed it in the Pachycephalosauria. I haven't seen any contradictory evidence (none was given in your paper, certainly), and stand by my statements regarding the flaws in your rationale for excluding it. But as I also said, with the recent discovery of Yinlong, we should reexamine Stenopelix to determine if its pachycephalosaur characters are also found in basal ceratopsians.

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.

One can indeed manipulate the data to affect the outcome. But at least in cladistics such manipulation is transparent and has an objective effect on the tree.
The Prenocephale/Sphaerotholus issue was specifically not tested by my analysis, as I previously said. Moreover, it's a subjective decision to synonymize them even in your (2003) phylogeny, as the American species are in a clade sister to P. prenes. And it's especially contentious if you keep Tyolocephale separate, as I previously said, since only some of your trees place P. prenes closer to the American species than to Tylocephale.
I never claimed Ornatotholus was distinct from Stegoceras. I specifically wrote both you and Williamson and Carr interpret it as a juvenile Stegoceras, and that exclusion of it and the other juvenile OTU (Wannanosaurus) did not affect the cladogram.
I also never claimed all flat-headed pachycephalosaurs were inherantly primitive. The fact flat-headed Dracorex was resolved as a pachycephalosaurin should have made that clear enough. My point was that just because some flat-headed pachycephalosaurs (Dracorex) are derived from dome-headed taxa, that does not mean all others (Homalocephale, Goyocephale) are. I stand by my statements that your reasons for deriving the latter from dome-headed taxa are flawed. It would be nice to hear you defend them.

Mickey Mortimer