ORNITHISCHIAN TAXONOMY GOES BANANAS

[Tetanurae@aol.com]

                                 ^v^or^v^

WHAT HAPPENS WHEN TWO PEOPLE DO RESEARCH INDEPENDANT OF EACHOTHER ON OPPOSITE
SIDES OF THE PLANET

I just got ahold of a paper today published by Cooper in 1985 that has a
cladistic analysis of the Ornithischia.  Within the paper, Cooper comes to
many of the same conclisions and names many clades that are also named by
Sereno a year later.  Some of Bakker's clades are also named different
things.

He comes to the conslusion that ornithopods and _Lesothosaurus_ is the sister
group to all other ornithischians.  The all others group is named
Neornithischia and has a radically different definition than Neornithischia
sensu Sereno 1997 (= Cerapoda Sereno 1996).  Neornithischia sensu Cooper has
a thyreophyra clade and a marginocephalia clade (including heterodontosaurs).
 So, yes, Neornithischia sensu Cooper is esentially the same as Orbitoscuta
Bakker 1986.

Additionally, he names the group Bakker calls Phytodinosauria:
Ornithosaurischiformes, the Sauropodomorpha is called: Pachypodosauria, and
Theropoda is called Carnosauriformes.  ACK!

Cooper also gives the name Neornithopoda to the clade (Heterodontosauridae +
(Pachycephalosauria + Ceratopia)).  Besides the fact that it has a Neo-
prefix, I think  this name should be ignored because it implies an ingroup
relationship within the Ornithopoda...

Back to Neornithischia.  I am utterly confused as to why Sereno (1997) drops
the name Cerapoda in favor of Neornithischia, since, as far as I know
Cerapoda has not already been named (it is actually a gramatically incorrect
word combination that was apparently a random joining of Ceratopia and
Ornithopoda...), and it differs significantly from the group originally given
that name by Cooper in 1985.

So, yes, fun.

Peter Buchholz
Tetanurae@aol.com

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Bakker, R T.  1986.  The Dinosaur Heresies - New theories unlocking the
mystery of the dinosaurs and their extinction.  Kensington Publishing
Corperation.  New York.  481 pages.

Cooper, M R.  1985.  A revision of the ornithischian dinosaur _Kangnasaurus
coetzeei_ Haughton, with a classification of the Ornithischia.  Annals of the
South African Museum - Cape Town 95(8):281-317.

Sereno, P C.  1986.  Phylogeny of the bird-hipped dinosaurs (order
Ornithischia).  National Geographic Research 2(2):234-256.

Sereno, P C.  1997.  The origin and evolution of dinosaurs.  Annual Review of
Earth and Planetary Sciences 25:435-489.