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Re: DROMAEOSAUR "SICKLE" CLAWS




----------
> From: Gigi Babcock or Ralph Miller III <gbabcock@best.com>
> To: vonrex@gte.net; jwoolf@erinet.com
> Cc: franczak@ntplx.net; dinosaur@usc.edu
> Subject: Re: DROMAEOSAUR "SICKLE" CLAWS
> Date: Monday, September 08, 1997 2:47 PM
> 
>  Peter Von Sholly <vonrex@gte.net> writes:
> > I agree.  Tracy Ford says the really large claw (on _Deinonychus_) is
> known
> > from a single specimen.  And _Dromaeosaurus_ claws are nowhere near
that 
> > big, from what I can see.
> 
> Chris Campbell writes:
> >This, I think, should be a critical part of determining the hunting
> behavior of >dromaeosaurs.  How much force can they exert with their
jaws? 
> Most of the >discussion here's been centered around that one big claw;
> before we can >really talk about behavior, though, we have to see what
> other characters might >support a given lifestyle.  Force per unit area
> exerted by the jaws is a huge >part of that, at least in modern
carnivorous
> mammals (and birds?  Do raptors >have especially powerful jaw/beak
> muscles?); if that force isn't terribly great >any notion of pack hunting
> in these animals is kinda silly if the claws aren't >used as weapons.
> 
> According to <Dinosaur Discoveries> Issue #2, a recent return to the
Lower
> Cretaceous Cloverly Formation (whence came the original _Deinonychus_
> material which John Ostrum excavated and described in the 60's),
conducted
> by the Museum of the Rockies and a crew of volunteers, succeeded in
> recovering a number of _Deinonychus_ skull elements as well as two feet,
> two hands, and an assortment of other bones ("many dozens of bones" in
> all).  In this brief article, Dr. W. Desmond Maxwell and Dr. Lawrence M.
> Witmer describe new information gleaned from the skull elements, which
are
> reportedly sufficient to enable an accurate reconstruction of the entire
> skull.  Among the distinguishing features germane to our topic is a
robust
> parietal sporting a large nuchal crest which would have anchored those
neck
> muscles used in retracting the head vigorously "probably during feeding."

> The robust frontal and parietal are said to compare much more closely to
> those elements of _Dromaeosaurus_  than to those of  _Velociraptor_. 
> Further comparisons cited in the article distinguish the skull of
> _Deinonychus_ as being quite unlike _Velociraptor_ in overall
proportions. 
> 
> 
> Drs. Maxwell and Witmer published the following papers on this new
> _Deinonychus_ material:
> 
> MAXWELL, W.D. and  L.M. WITMER, 1996, New material of _Deinonychus_ 
> (Dinosauria, Theropoda), <Journal of Vertebrate Paleontology>, 16(3)
> Supplement: 51A.
> 
> WITMER, L.M. and W.D. MAXWELL, 1996, The skull of _Deinonychus_
> (Dinosauria, Theropoda): new insights and implications, <Journal of
> Vertebrate Paleontology>, 16(3)  Supplement: 73A.
> 
> As I do not have ready access to these papers, I wonder if others on the
> list could comment on (1), the size of the #2 pedal claws in relation to
> the overall size of the _Deinonychus_ elements recovered (the DD article
> states that four of these claws were found during this excavation), and
> (2), does the more complete skull material give us a clear picture of the
> animal's biting strength?
> 
> Speculations of dromaeosaur "kitty cat kicking" aside, I am keeping an
open
> mind about the behavior of these amazing creatures.  When it comes to
> dinosaur behavior, I think that's usually the most reasonable approach
> (unless you're a movie producer).  If dromaeosaurs didn't use their pedal
> unguals offensively, that's front page news.  Right up there with John
> Horner's characterization of _Tyrannosaurus rex_ as a strict scavenger (a
> view immediately embraced by paleontologists worldwide).  OK, John Horner
> does see _T. rex_ picking off an occasional live animal once in a blue
> moon.
****************************************************************************
*******************
The last couple of posts that I've read on _T.rex_ have bashed Horner's
hypothesis (and him to some extent).  Cut the man some slack.  He was doing
the best that he could do with the evidence at hand, and that's all that
any of us can ask.  Plus, let us keep in mind some of the cutting-edge
info. coming out of his lab @ M.S.U. (Schweitzer's Isolation of
Bio-Molecules in _T.rex_ bone, for example :-} ).

Casey T.
TuckerCJ@MUohio.edu
Miami University
Oxford, Ohio
****************************************************************************
*********************
> 
> Ralph Miller III <gbabcock@best.com>
> 
> Q: What was T. Rex doing with those puny little arms?
> A: Holding the microphone while he was singing "Get It On (Bang A Gong)."
 
>