[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
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