WHAT CAUDIPTERYX SAYS

[darren.naish@port.ac.uk]

I am truly intrigued by the news from Ostrom Symposium participants 
that _Caudipteryx_ is grouping with oviraptorosaurs. This is 
obviously not a truly novel idea to those of us on the list, and it's 
nice to see it supported. Were any characters mentioned that favoured 
this placement, or were you only subjected to a brief glimpse of a 
cladogram? 

Besides the lower jaw (which, as Ji et al. noted, is 
oviraptorosaur-like), the femur and ischium of _Caudipteryx_ look 
oviraptorosaurian. The femur appears to have a robust, finger-shaped 
anterior trochanter like that of oviraptorosaurs (_Microvenator_ 
has a very weird, unusually prominent ant. troch.) while the fourth 
trochanter is apparently absent - something also seen in 
_Microvenator_ (Ostrom 1970, Makovicky and Sues 1998) - but a feature 
subject to lots of individual variation, as John Hutchinson has 
pointed out here before. _Caudipteryx_' distal, triangular and 
prominent ischial obturator process is reminiscent of that in 
_Chirostenotes_. The ilium looks oviraptorosaurian too.

(Incidentally, I suppose there's no harm in mentioning it: I have 
been working on MIWG 5137, a little Wealden femur that is rather 
reminiscent of the femur of _M. celer_.)

Something worth pointing out is that, *if* _Caudipteryx_ is an 
oviraptorosaur, it might tell us some important things about the 
group that were not previously knowable. First off, the things are 
feathered, and we now know the distribution of at least some of their 
feathers - I'm thinking specifically big arm feathers for the 
brooding oviraptors here. Secondly, as _Caudipteryx_ is small (as is 
_Microvenator_, but then the type specimen is a juvenile), 
oviraptorosaurs may have their roots in small ancestors. Third, 
_Caudipteryx_ has a belly full of gastroliths and certainly does 
not look predatory.. therefore it was probably an herbivore. Hey, an 
herbivorous oviraptorosaur! Does that sound familiar?

Fire at will.

P.S. UK Dinosaur Convention this Sunday (28th) at Conway Hall, Red 
Lion Square, London. Expect a blood bath as Rey, Naish and Howgate 
battle it out over _Protarchaeopteryx_ and its pals.. or not. 
Actually I'm talking about marine tetrapods (and one thing I will be 
figuring, as always, is a slide of Alvin pierced by a _Xiphias_).

DARREN NAISH
darren.naish@port.ac.uk