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RE: Coeluridae as a Wastebasket for Coelurosaurs



> From: Ken Kinman [mailto:kinman@hotmail.com]
>
> Jaime,
>       I don't recall Tom Holtz ever suggesting Coelurus is a maniraptoran
> (at least recently),

Came out that way in the SVP 2000 matrix, the Armour Symposium, and the
Ostrom Symposium (incidentally, for those interested, authors for the volume
of the latter sent back their page proofs a couple of weeks ago, so should
be published soon!!).

> and even placing it in Maniraptoriformes is rather
> iffy.  He did indeed place Compsognathids in Maniraptora for a while last
> year, but now he has them completely outside of Maniraptoriformes.
>       And if you apply his cladistic definition of Maniraptoriformes, it
> would include Tyrannosaurs in Sereno's cladogram.

Darn tootin'.

> There does seem to be
> some consensus on the more inclusive taxon Coelurosauria, but certainly
> *NOT* on the contents of Maniraptoriformes (not only is Sereno's
> different,
> but Holtz himself has compsognathids hopping in and out of it in very
> different positions just within the last year).

Actually, there is very strong consensus of the major components in there:
Ornithomimosauria,  Therizinosauroidea, Oviraptorosauria, Troodontidae,
Alvarezsauridae, Dromaeosauridae, and Avialae.  Tyrannosauroidea is either
in that clade or just outside, and then there is a batch of basal and/or
fragmentary forms which might or might not belong.

>  My {{Ornithomimidae to
> AVES}} does indeed appear to be a synonym of Maniraptoriformes Holtz
> (1995-96), but certainly NOT a synonym of Maniraptoriformes Sereno, 1999
> (which included tyrannosaurs) or of Holtz, 2000 (which included
> compsognathids).

Okay, Maniraptoriformes is EXPLICITLY a phylogenetically defined
(ancestry-based) taxon, NOT IN ANY WAY a content based taxon.  Get over it.
Maniraptoriformes is all descendants of the most recent common ancestor of
_Ornithomimus_ and Neornithes.  It doesn't matter what other taxa belong in
there; Maniraptoriformes is and always will be _Ornithomimus_, Neornithes,
their common ancestor, and all its descendants.

> I repeat, there is no consensus (especially looking at
> cladograms of 1999-2001).

I disagree, and indeed have presente work to the contrary.

> On the other hand, Lophotrochozoa is such a wastebasket that I won't
> recognize it even informally, and yet it is being passed off as a
> holophyletic clade and uncritically accepted as such by most biologists
> (which I think is far more damaging than any well-organized paraphyletic
> assemblage such as Coeleuridae).

Just because you don't like the clade doesn't mean that its synapomorphies
go away.  How precisely do you challenge the molecular data supporting the
monophyly of the lophotrochozoans?  That is, what additional *evidence* (not
feelings, evidence) do you put forth that better explain the data.

(Please note: I'm not committed to lophotrochozoan monophyly one way or the
other.  However, you've been harping on this case for a while without any
support for an alternative topology.  That is not sufficient evidence to
reject that clade).

                Thomas R. Holtz, Jr.
                Vertebrate Paleontologist
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
                College Park, MD  20742
http://www.geol.umd.edu/~tholtz/tholtz.htm
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796