Re: Bird flight once more (was Re: What is a Dinosaur? and semilunate carpal)

["Chris Fisher" <killerraptor20@hotmail.com>]

>   First, it would be good to clarify that dorsoventral movement of the 
> wrist only occurs if the
> arm is held outward, level to the horizon.

Imagine a traffic cop waving cars past - this is the movement of the hand I 
meant.  same orientation of the arm too.
Could a maniraptor direct traffic? :)

> Christ writes:

That must be a typo - or else this discussion is REALLY attracting some 
interest.
:)


> <The correlation is certainly their, but how does stiff wrists help 
> predation?>
>
>   Not helping predation [generally], but as I wrote: "a greater predatory 
> capability in the arms."
> This is previously explained as the abscence of a "wobble" in the hands 
> when the hand strikes the
> prey target. If flexible along the transverse axis, this strike would cause 
> the hand to rebound
> from the strike, and reduce penetrating depth of the claws, thus reducing 
> capability of affirming
> a grip.

But what about movement between the metacarpals and the carpal block - the 
distal surface of the semilunate carpal. Could this act as a hinge? How was 
this contact strengthemed - or that between individual phalanxes.

I'm thinking all these changes made the arm and hand better for HOLDING prey 
but not very good for FEEDING -  like using the hand to bring food to the  
mouth

Thanks, Chris

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