RE: Forelimbs of "Terror Birds"

["Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>]

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> ArtSippo@aol.com
>
> The premier of WWPB last night showed a Diatryma like bird with
> wings bent backward on the chest.  My understanding is that new
> findings suggest the fore limbs in these birds had digits with
> claws that projected forward like those of carnosaurs.  Which is
> the predominant opinion at this time?

_Diatryma_ (and its kin/senior synonym? _Gastornis_, featured in the first
part of WWPB) are not "terror birds" (= phorusrhacids).  I don't know of the
complete forelimb of any gastornithid is known, but they what is known is
that they were highly reduced (perhaps more so than shown in the
documentary).

I unfortunately missed the section with true _Phorusrhacus_, so I didn't see
what sort of wing they showed.  However, it should be pointed out that the
"foreward pointing claw" has only been found in a few (in fact, I believe in
only one) species of phorusrhacid, so that it might be inappropriate to
apply this highly derived morphology to all members of the 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