Deinonychus claws

[tlford@ix.netcom.com (Tracy Ford)]

You wrote: 
>

>
>Maybe; but the only part of the toe that would be on the ground is phalanx
>II-2.  That wouldn't provide a lot of support.  It looks to me like the only
>part of the second toe that touched the ground was the "knuckle" between
>phalanges II-1 and II-2.
>
>
Are you getting that idea from Ostrom 1969, page 132, figure 74? It's quite 
different from what Greg draws, and you can lower the first phalange to touch 
the ground.

>>  And what about the animal's ability to walk, run and balance?  
>
>And why is digit II so short and directed away from the direction of
>movement?  And why are phalanges II-1 and II-2 set up to articulate at up to
>a 90-degree angle to each other? 

So it can use the claw to slash.

 And why are the muscle attachment sites on
>the second toe so much more prominent than on the other toes?  And what about
>that enormous, nearly semicircular claw? 

Because it's a big claw. And not all the Mt big claw have such a large 
semicircle. See my article in the Prehistoric Times, Mar-Apr, Number 23: 28-29, 
and of course Ostrom, J. H. 1976. On a new specimen of the lower Creta
ceous Theropod Dinosaur Deinonychus antirrhopus. Breviora, No. 439: 1-21.

 Unless it was held up at least to
>some extent, every step would have driven it into the ground!
>

Not necessarily. The pad would be very large, and it would have to be, just 
look at how large the puduncle on the lower end of the claw is.

>(I have copies of Ostrom's drawings of the original foot in front of me--_The
>Dinosauria_, p. 275)

How can you have Ostrom's original foot drawings if its the Dinosauria your 
using? You are using Ostrom 1969.
>


Tracy