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RE: Dino reputation 'is exaggerated'

With all do respect to Phil, I had previously concluded a piercing
function for raptor claws. See my paper on evidence of predator behavior
in theropods: 

Kenneth Carpenter, Ph.D.
Curator of Lower Vertebrate Paleontology/
Chief Preparator
Department of Earth Sciences
Denver Museum of Nature & Science
2001 Colorado Blvd.
Denver, CO 80205
Phone: 303-370-6392
Fax: 303-331-6492
for PDFs of some of my publications, as well as information of the Cedar
Mountain Project: 

-----Original Message-----
From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu] On Behalf
Of don ohmes
Sent: Thursday, October 13, 2005 9:48 AM
To: dinosaur@usc.edu
Subject: Re: Dino reputation 'is exaggerated'

I'm not trying to characterize Velociraptor (V.) as a
sauropod predator... your analysis of V.'s lifestyle
may (or may not) be entirely correct. However, note
that the diameter of a cow's neck is not that
different from a sauropod's... so the question should
be "can a velociraptor climb and kill a cow". };) 

I am trying to make a point about possible dromaeosaur
claw function (locomotive device as opposed to
resource acquisition weapon), relative to the
vulnerabilities of large sauropods, and I am willing
to use V. as a model.

It is concensus that sauros had good reason to make
their necks as light as possible. My hands-on
experience only includes cows, deer, alligators,
turtles, birds and rattlesnakes; however, I can report
that mammalian skin can be _much_ tougher, relative to
shear, than reptilian or bird skin. Perhaps sauro skin
was tougher than elephant hide, but I don't believe
that is a warranted assumption relative to the distal
portion of the neck, unless there is fossil data. 

It is also concensus that sauros had very high blood
pressure; high blood pressures imply rapid blood loss.
Also, the longnecked sauros may not have been capable
of rapid and drastic (ie, defensive) head and neck

V.'s teeth were sharp, and 2-3 cm long; I conclude
that if perched on the distal end of the neck, even
the unlikely V. (or a swarm thereof) might well have
had the physical tools necessary to bring down a large
sauro. (Note again that I am NOT saying this was part
of V.'s behavioural repertoire.)

What has been missing (before Manning et al) is a
practical method of placing V. (or more to the point,
it's larger relatives) in the right spot; if the
sickle claw could function as a locomotive device
analgous to treeclimbing spikes, on a substrate of
sauropod, then a practical scenario begins to
coalesce. I personally prefer emphasis on the
climbing/propulsive aspect of claw function, feeling
that "sticking" functions were mostly relegated to the
front claws and teeth (could dromaeosaurs "lock" their
jaws like a bulldog?)... greatly looking forward to
the coming exspansion paper.

--- Jorge Dichenberg <jorgedich@yahoo.com> wrote:

> --- don ohmes <d_ohmes@yahoo.com> wrote:
> > Seriously, sauropods were slow, weren't they? And
> if
> > Velociraptors could climb trees, why couldn't they
> > climb a startled sauropod? 
> Imagine a cat trying to climb a cow and kill it.
> Improbable, isn't it? 
> I was simulated and looked at skeleton of
> Velociraptor. 
> There exists a living mammal matching amlmost all
> adaptations of it. It has big eyes, long skull,
> small
> sharp teeth, carries it's head forward, has big
> claws
> (although on foreleges, not hindlegs), long body,
> shortened legs and long tail which can be pointed
> vertically. It is predator, very active, lives in
> groups in sandy semi-deserts. 
> This description fits, surprisingly, a meerkat.
> Small
> predator adapted to running in dense vegetation,
> digging and climbing. Claws are used for digging and
> climbing. Even combination of shortish legs and tail
> which can be pointed upwards fits - it is used by
> meerkats to keep visual contact in thick vegetation.
> Pack of meerkats can be fierce. But they typically
> hunt animals much smaller than their size. 
> In contrast, Velociraptor has adaptations
> contradictory to modern big predatory mammals (ones
> that hunt animals bigger than themselves). Big claw
> is
> not supported by thick leg bones needed to withstand
> forces when fighting prey. Modern big cats and polar
> bears have much thicker legs and jaws. Velociraptor
> has thin bones and elongated skull - not suitable
> for
> wrestling. Head facing forward makes no sense in
> animal confronting prey much higher than itself.
> Legs
> are shortened which is not a good adaptation for
> fast
> running or jumping. Extremely long tail would be
> very
> vulnerable to breaking or indeed, biting by prey.  
> In short, it was a small predator, not a big one.
> For
> Velociraptor, peaceful Dinotopia is better than
> violent Jurassic Park. ;)
> J.
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