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Re: Thero palms, Prehistoric Times, and grants



"Thomas R. Holtz, Jr." wrote:

> Sereno argues that all theropods from herrerasaurids on up walked with palms
> inward.  However, having seen palm prints for probable coelophysoid tracks,
> I suspect that the palms-inward orientation has to do more with the
> development of the semilunate carpal block, a structure now known to be an
> avetheropod, and possibly tetanurine, feature.  (Note that an *enlarged*
> semilunate carpal block, as seen in troodontids, oviraptorosaurs,
> _Caudipteryx_, _Protarchaeopteryx_, dromaeosaurids, and birds, still seems
> to be synapomorphic for Maniraptora).

I didn't attend the Ostrom Symposium, and I am wondering where the
compsognathids nest in the latest cladograms.  I would also like to know if
there is at present a consensus regarding the anatomy of the compsognathid
wrist.  In _The Encyclopedia of Dinosaurs_, the cladograms by Holtz (1994),
Gauthier (1986), and Holtz (1996), presented in FIGURE 1 on page 412 (within
Kevin Padian's "Maniraptora" article), differ in their assessment of this
feature.  The Holtz cladograms place _Compsognathus_ outside of the Maniraptora
(as then defined) in the 1994 analysis, and outside of the Maniraptoriformes in
the 1996 analysis, meaning that this genus did not exhibit the "maniraptoriform"
forelimb and manus anatomy.  By contrast, Gauthier's analysis considers
_Compsognathus_ to possess these characters, placing it within the taxon,
Maniraptora, as it was defined at the time (1986).  (The article explains that
the most recent of these cladograms, Holtz, 1996, redefined Maniraptora as a
more exclusive group, comprised of only Dromaeosauridae and Avialae in the
cladogram at the bottom of page 412).

On the other hand, Thomas Holtz' quote above (March 1999) uses the taxon
"Maniraptora" to define a much larger group.  Has the definition changed again,
or is the last word in parentheses in Holtz' post above supposed to be
"Maniraptoriforme"?

Regarding the diagnosis of _Compsognathus_, I am sure that some of this
disagreement derives from the disarticulated nature of the carpal and manual
elements of the _Compsognathus_ specimens, and the fact that some of these bones
are missing altogether.  Following the discovery of the well-preserved
_Sinosauropteryx_ specimens (four specimens in all, the last I heard), the
wrists and hands of compsognathids should be easier to assess.  The "Theropoda"
article, written by Philip J. Currie, which is also in _The Encyclopedia of
Dinosaurs_, includes the following passage on page 733:

"(MANIRAPTORA) has been redefined by Holtz (1996) to include only all theropods
closer to birds than to ornithomimids.  He went on to establish the taxon
Maniraptoriformes, defined as the most recent common ancestor of _Ornithomimus_
and birds and all descendants of that common ancestor (Fig. 2).
Maniraptoriformes are characterized by a pulley-like wrist joint that allowed
the hand to be pulled back against the body.  This characteristic was
secondarily reduced or lost in ornithomimids and tyrannosaurids.  Recently
discovered compsognathids (see FEATHERED DINOSAURS) have well-preserved hands
that suggest that this character was more widespread among coelurosaurs."

Does the compsognathid condition then qualify as Maniraptoran, Maniraptoriforme,
or is the carpal condition not advanced enough to warrant inclusion into either
of these taxa?

> Galton and Sereno both have papers on theropod (or more generally,
> saurischian) hand orientation coming out in the near future (DinoFest volume
> at least, maybe elsewhere too).

We're all looking forward to that!

In the mean time, I direct interested parties to the latest _Prehistoric Times_,
Feb/March 1999, No. 34.  It features a  fine article by Tracy L. Ford entitled
"How many fingers did _Compsognathus_ have?"  The article includes
reconstructions of _Compsognathus_, _Sinosauropteryx_, and _Scipionyx_, and also
illustrates the hands of many of the theropods.  The magazine also covers the
SVP meeting and  a 1999 Dinosaur news wrap-up.

A _Prehistoric Times_ article (same issue) by Don Lessem discusses The Jurassic
Foundation (formerly known as "The Jurassic Park Foundation"), a new nonprofit
organization established to fund international dinosaur research.  The
scientist-dominated foundation board, including its chairman, Dr. Philip Currie,
is entirely volunteer, to ensure that money received goes to research grants, to
be funded in amounts up to $5,000.   Dr. Currie is president of the foundation;
Cathy Forster and Jack Horner are on the Board of Directors.  Unlike The
Dinosaur Society, there are no publications under way at this time, nor is there
any funding for artists or education, but these are possible in the future.  The
first deadline for grant proposals was January 15, 1999.  The foundation derives
most of its money from revenues provided by the Jurassic Park/Lost World
exhibit.  There was, unfortunately, no contact information provided in the
article.

Please feel free to post any corrections to the above.
--
Ralph W. Miller III  <gbabcock@best.com>

Anybody can see that _Compsognathus_ was much too small to dribble a basketball.