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*Caudipteryx* and the Mysterious Chimaera



  Funny how the BAND group brings the pessimist out in
me. Advocates of the BAND set argue that the numerous
features in "dinobirds" allying them to birds are
convergent or as a result of chimaeric association.
The numerous features which ally such taxa as
*Rahonavis* and *Caudipteryx* to Aves, or Avialae, or
Paraves, or whatever group there is _now_, cannot be
convergent based on the sher weight of themselves
(though it _is_ likely -- very unlikely, but likely
still in chaotic time and evolution). But under this,
a real nice anatomical analysis would be nice, not
just a phylogenetic perspective, based on the
associated arbitrariness that comnes with that group.
Get fifteen workers together, compose _several_
different matrices with different inclusive taxa,
tabulate about 5000 or more trees, publish them in a
comparative phylogenetic work (I don't think this has
been done before) and see what pops out.

  This is what impressed me most with Holtz' poster
and abstract at SVP this year -- that fact that he
analyzed the consensus and conflict in various recent
trees, and found some certain truths involved in them,
based on different matrices and such, and these even
agreed to a large degree with Gauthier (1986). We've
found more stuff since Gauthier did his analysis, and
we all thank him for that, because who _doesn't_ cite
characters of his in their matrices on dinosaurs?
Specifically theropods? Sure there have been critics
of his analysis, most notably Charig and Milner
(1990), but these hardly invalidate the work.

  But back to the subject line, it would be most
impressive to find a consensus tree among Xu et al.'s,
Ji et al.'s, Holtz', Sereno's, and Norell et al.'s,
the last three all soon to be published, which will
help resolve much of the conflict in this area. It
will be nice to note where Norell and Makovicky (in
press) find Troodontidae places, considering it will
help resolve the Maniraptora/Maniraptoriformes area to
some degree.

  But *Caudipteryx*? Feathers as preserved in the
specimens as impressions with apparent carbonized
traces are unlikely to have been transported to been
moved as part of the arm to reassociated with a
shoulder as in the type, because they are in perfect
relation to the rest of the limb. It's fun to note the
dissention in the BAMM or BCF hypotheses because we
all find time to look up the cited references to see
if that does, indeed, state that, or whether the date
needs to be reexamined, or the specimen for that
matter, to confirm or deny an hypothesis. This is
science, and this is why I chose this field, much to
my relatives' and some local friends'
misunderstanding. I guess you have to "have the bug"
to really get into it.

  But Geist et al. (1999) raised the question at SVP
on the chimaeric nature of *Caudipteryx;* if this were
a court of law, the burden of proof would be on them;
so let it stand, I say. There are some undeniable
oviraptorosaurian features in the skull of
*Caudipteryx* -- however, the postcrania does not
possess some features, while some do; others are found
in the dromaeosaur-Archie lineage, hence the broader
phylogenetic placement in Ji et al. (1998) at least as
I see it. So for now, I would wait until *Caudipteryx*
is explicitly examined with oviraptorosaurs.

---

  On the sideline I raised above, I would also like to
draw attention of Frankfurt and Chiappe (1999); while
not to the specimen of their analysis, they approach
phylogenetic taxonomy in an intriguing way, by
analyzing characters in a single cervical vertebra to
check its distribution among a variety of taxa, birds
_sensu stricto_ and theropods _sensu stricto_,
including *Herrerasaurus* in the analysis. Hence, the
matrix/tree analysis can be used outside of a
phylogenic perspective to analyze homoplasy or
homoplasticity without having to argue for phylogeny;
this can be done for all regions of any supposed
chimaera in a means to check parsimony of trees to see
if in fact the animal is composed of features
separating it into various animals -- not very useful
if the animal is apparently taphonomically an
individual, as in "Archaeoraptor" (and may God forgive
Czerkcas and Czerkcas for choosing such a name! :) ),
but very useful if the animal is found jumbled or
composed of startlingly different morphologies, as in
*Avimimus.*

  There's a few thoughts from the jumbled mind of
JAIME!!!! [big echoing sounds of my name bouncing
around your skulls, all] :)


=====
Jaime "James" A. Headden

"Come the path that leads us to our fortune."

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