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Re: Mongolian dinosaur inspires religion in grad student



At 02:07 PM 10/1/96 -0500, Nino wrote:

>Do you know that nearly all of the teeth character states are the same for
>Ornithomimosauria (not Ornithomimoidea; and you have to include here

        The taxonomy is twisted because it is a work-in-progress...
        I am currently unclear on exactly how the systematics of the
ornithomims works.  I know that there is a semi-ordinal taxon
Ornithomimisauria, which sounds more than a tiny bit excessive to me (GSP
says they're all in three genera, just to illustrate the opposite trend...).
Since I have never heard a cladistic definition of that taxon, I hoped there
wasn't one, and used it for the as-yet unnammed clade defined by
Tyrannosauroidea (here again, I doubt a taxon larger than a super-family is
necessary to adequitely describe this group) plus Ornithomoidea.  I disagree
with Holtz (pers. com.), this taxon needs a name.  Of course, in the
phylogeny I presented, this taxon recieves his name Bullatosauria.
        I am still unclear on how to handle the apparent "synonomy" of a
stem-based clade and a node-based clade...
        Note that, in the above, I assume Ornithomimoidea to be "all animals
more closely related to Ornithomimus than to Troodon or Tyrannosaurus."
Presently, this gives Ornithomimisauria: "all animals more closely related
to Ornithomimus than they are to Troodon", or "the most recent common
ancestor of Tyrannosaurus and Ornithomimus and all of it's decendants."  If
the first is accepted, than it the Ornithomimisauria conveniently disappears
into synonomy with Ornithomoidea (which, being an elevated family-rank
taxon, should have priority) when the Bullatosauria excludes the
Tyrannosauria.  In any case, if I can't do this, my public apologies to
those who named these taxa.

>_Pelecanimimus_ for the teeth characters), Troodontidae and (I think)
>Alvarezsauridae? Have you included _Pelecanimimus_ in your analysis?

        But of course!  The D-shaped premax teeth of Pelicanomimus are
probably what keeps making the ornithomims come out as sister to the
tyrannosaurs!
        I do realize that these traits are found in troodontids,
ornithomims, and alvarezsaurs (IMHO these are oviraptorsaurs anyway...).  I
was trying to make a case both for therizinosaurs as oviraptorsaurs, and as
coelurosaurs, hence the confusion (possibly I worded the post too
confusingly, I'll have to be more careful).  In the phylogeny I presented,
these characters end up scattered all about the coelurosaurs, yet many of
them do show up as synapomorphies of the Oviraptorsaria in their current
position as sister to the Maniraptoriforms.
        :)
        Wagner
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| Jonathan R. Wagner                    "You can clade if you want to,     |
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