RE: New papers in Acta Palaeontologica Polonica -- a very late response

["Toby White" <mwhite@houston.rr.com>]

About 6 months ago, there was some discussion of Maryanska et al.
(2002), a paper which placed oviraptorosauria among birds.  At that
time, Tom Holtz suggested. "It would be, I think, an excellent exercise
to include some non-confuciusornithid birds in the analysis, and see how
it modifies the structure they found."  

I finally got around to trying this.  I restored the taxa which the
authors had dropped from the study and added a "Neornithes" taxon.
Being unsure of the coding for some characters, I tried it several ways.
This only makes things weirder.  No matter what the details are within
Oviraptorosauria, the general topology (outgroups omitted) is:

Maniraptoriformes
|--Ornithomimosauria
`--+--Alvarezsauria
   `--+--Therizinosauria
      `--+--Archaeopteryx
         `--+--+--Troodontidae
            |  `--Dromaeosauridae
            `--+--Confuciusornithidae
               `--+--Neornithes
                  `--+--Avimimus
                     `--oviraptors & Caudipteryx

Dr. Holtz mentioned concerns with characters 72, 96 & 97, dealing with
the mandibular symphysis and dentition.  I eliminated these characters,
with the result that the positions of alvarezsaurs, troodonts and
dromeosaurs became completely unstable.  This change did not affect the
relative positions of the other groups.  In particular, oviraptors
continued to be birds (= Archaeopteryx + Neornithes) in every tree, and
Avimimus continued to be the sister of Oviraptorosauria, with
Caudipteryx still variably nested in the oviraptors.  

  --Toby White
http://www.palaeos.com

Maryanska, T, H Osmolska & M Wolsan (2002), "Avialan status for
Oviraptorosauria." Acta Pal. Pol. 47: 97 –116.