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Re: Feathered tyrannosauroids; it's delightful, it's delicious...



David Marjanovic wrote-

> The skull is very reminiscent of *Ornitholestes* and *Proceratosaurus*.

I agree, especially in regards to the latter.  Has anyone suggested
Proceratosaurus' small premaxillary teeth are homologous with
tyrannosauroids'?  I noticed that while coding a while back.  Also note the
suprantorbital fossae, that although on the maxilla, are identical in
position with the nasal fossae of carnosaurs.  Is it possible the
nasomaxillary boundary shifted while leaving the airsacs in place?  The dual
nasal ridges are also carnosaurian.  Very odd scapulocoracoid, looks
coelophysoid.  Thin digit III reminds me of "Tanycolagreus".

> Xu et al. have run a cladistic analysis (dataset of Currie et al. 2003,
all
> characters treated as unordered; inapplicable characters are present in
the
> matrix, but NONA, which was used, can deal with them). It can be found in
> the Supplementary Information... and here's what the single shortest tree
> looks like:
>
> +--*Allosaurus* (outgroup)
> `--+--*Sinosauropteryx*
>    `--+--*Gallimimus*
>       `--+--+--*Velociraptor*
>          |  `--*Dromaeosaurus*
>          `--+--*Sinovenator*
>             `--+--*Citipati*
>                `--+--*Dilong*
>                   `--+--+--*Albertosaurus*
>                      |  `--*Gorgosaurus*
>                      `--+--*Daspletosaurus*
>                         `--+--+--*Nanotyrannus*
>                            |  `--*Tyrannosaurus*
>                            `--+--*Alioramus*
>                               `--*Tarbosaurus*
>
> Something tells me they should have included a few more taxa.

No, just more characters.  Currie et al. 2003 was designed to test
tyrannosauroid phylogeny, not coelurosaur interrelationships.  It's the same
error Lu et al. (2002) made when adding oviraptorosaurs to a bird matrix.

I know what I'll be adding to my analysis tonight...

Mickey Mortimer
Undergraduate, Earth and Space Sciences
University of Washington
The Theropod Database - http://students.washington.edu/eoraptor/Home.html