FW: The "ideal" Eumaniraptoran arm motion

[Jeffrey Martz <jeffmartz@earthlink.net>]

<Still, biological life forms must obey physical principles. They atmospheric
<friction, drag, whatever, that would be caused by cardboard or feathers,
<whatever, would tend to slow down the arms as they are swept forward in <the 
"ideal" prey catching motion that maniraptorans were capable of. 

[Jeffrey Martz]  
     Sure, but would it slow it down enough to prevent it from catching 
something small and fast?  If increasing the area of the insect net increases 
insect catching more then drag on the feathers decreases it, then it might be a 
worthwhile trade-off.  I not necessarily trying to defend the insect net idea, 
which can be objected to for a number of reasons.  I've never been crazy about 
playing the "what if" game with flight origins.  My point was that humans 
slapping cardboard together might not be the best model for theropods snatching 
at something with their arms.
     In any case, I'm not certain that those who suggest that maniraptioran 
adaptations in the wrist were for prey catching are thinking in terms of 
insects and insect nets, or even having prominent feathers on the arm at all.  
I believe Ostrom proposed that idea for the origins of large feathers on the 
hand and forearm, not pectoral girdle and wrist adaptations (which would have 
come earlier). 
 
LN Jeff