Re: So-called Sickle Claws

["Peter Von Sholly" <vonrex@gte.net>]

To my mind, it all depends on the pads on the bottom of the foot as to what
the stance would have been like.  Again, ostriches only have two toes.

----------
> From: Dann Pigdon <dannj@alphalink.com.au>
> To: dinosaur@usc.edu
> Subject: Re: So-called Sickle Claws
> Date: Monday, August 25, 1997 3:26 PM
> 
> Peter Von Sholly wrote:
> > 
> > I disagree.  I believe there was a large "heel pad" under the distal
ends
> > of the 3 metatarsals and that all three toes bent forward from there,
with
> > pads of their own, especially under the claw of digit 2, the so-called
> > killer claw.  There is plenty of room for that toe to reach the ground.
 I
> > think one can easily get the wrong idea by looking only at the bones
and
> > foregetting what the soft tissues would do and the space they would
fill.
> > And what about the animal's ability to walk, run and balance?  You
don't
> > think that would be compromised by the need to walk only on its two
outer
> > toes?  To me it creates an unrealistically awakward , compromised
creature.
> > Also, absence of evidence may indeed not be evidence of absence, but
where
> > are the two-toed footprints, after all?
> > 
> 
> Ostriches cope quite well with only two toes per foot. I think the
> closest modern analogy for dromaeosaurs would probably be the
> cassowarie. It has a modified inner toe claw that is quite distinct
> in shape from the others. It is shaped like a long bladed carving
> knife, and it uses this as a weapon to defend itself, its young,
> or its territory. However the claw is still straight and the toe
> bears weight like the other two. I would expect that if dromaesaur
> inner foot claws also bore as much weight as the other two load
> bearing ones it would probably have been straighter that it was.
> To suggest that such a large curved claw was part of a toe that
> bore as much weight as the others to me suggests a creature that
> would have been even more disabled that one that had only two
> fully load bearing toes.
> 
> -- 
> ____________________________________________________
> 
>       Dann Pigdon
>       Melbourne, Australia
>       http://www.geocities.com/capecanaveral/4459/
> 
> ____________________________________________________