Re: DIATRYMA

[Tom Holtz <tholtz@geochange.er.usgs.gov>]

>I have read two opposing views of Diatryma and am very interested in knowing
>which is most likely to be correct.  In this month's NATURAL HISTORY, there
>is an interesting article (among others) concerning this flightless behemoth.
> The article states "...Diatryma was no terror crane, having possessed
>neither the adaptations of a predator nor any affinity with cranes.  The jaws
>of Diatryma, although massive, lacked the pronounced hook typical of raptors,
>or birds of prey.  The huge beak was apparently adapted for crushing and
>slicing the rank vegetation that cloaked the warm temperate and subtropical
>forests..."  However, in Dr. David Norman's PREHISTORIC LIFE  Diatryma is
>described as having "...a huge head, with a very deep, powerful beak capable
>of crushing the bones of its prey...It seems quite likely that they would
>have been able to leap at their prey, taloned feet outstretched, as the first
>stage of attack, before delivering a bone-crushing bite to the victim's
>neck."
>     I would appreciate any opinions on this subject.  Thank you for your
>time.

The article in Natural History was written by A. Andors, an advocate of an
herbivorous habit for Diatryma.  Counter-arguments (presenting evidence for
a carnivorous habit) were published by Witmer and Rose (or was it Rose and
Witmer?) a few years back in Paleobiology.

Personally, as Diatryma skulls are the same gross morphology as many other
nonmammalian predatory terrestrial tetrapods (say THAT three times fast
;-),  that is to say, they show the "meat-cleaver" morphology found in
predatory terrestrial archosaurs and basal synapsids, I'd say that these
birds were at least partly predatory.

                                
                 Thomas R. Holtz, Jr.                  Phone: 703-648-5280      
                 Vertebrate Paleontologist         Fax:    703-648-5420
tholtz@geochange.er.usgs.gov ------------>       th81@umail.umd.edu
U.S. Geological Survey          ------------->       University of Maryland
Branch of Paleontology & Stratigraphy ---->       Department of Geology
MS 970 National Center
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