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




OK, I'm putting my head in the lion's mouth here...

        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.

In Mickey's defense, he made no bones about this (no pun intended). In fact, he wrote: "Note I didn't include Sullivan's characters in the analysis, nor did I check the accuracy of the codings. So this post isn't a test of his ideas on pachycephalosaurid phylogeny."


I think the gist of Mickey's message was to refute the assumption that a cladistic analysis would NOT work for pachycephalosaurs. This assumption was made abundantly clear in Bakker et al. (2006), especially with the characterization of unweighted cladistic analyses as "mixing apples and oranges, bowling balls and cannon balls, BB's and seeds from currants". Although the comment is undoubtedly tongue-in-cheek, it also comes across as somewhat provocative. My first thought when I read the paper was "Yes, you could be right - a cladistic analysis might not tell us anything useful. But what would be the harm in doing one anyway?"

He selectively chooses to embrace (some) previous interpretations that result in a nice (albeit
simplistic), neatly nested, hypothetical hierarchy. [snip]
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.

I didn't interpret Mickey's analysis in this way, since (as you note) he was simply "combing the literature for characters". As far as I can tell, the fact that the flat-headed taxa _Goyocephale_ and _Homalocephale_ were recovered by Mickey as basal pachycephalosaurs had very little to do with previous interpretations, or with manipulation of data. This just happens to be what his cladistic analysis spat out after the raw data were pushed through. I don't think he had a vested interest in demonstrating that all flat-topped pachies are primitive, any more than he had a vested interest in demonstrating that _Dracorex_ clusters close to _Pachycephalosaurus_.


Anyway, it's nice to see pachycephalosaurs getting some attention on this list.

Cheers

Tim