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RE: The "ideal" Eumaniraptoran arm motion



<Try running along, with some pieces of stiff cardboard in your hands to
 approximate the surface drag that would be produced if you had feathers
 attached (enough for near flight conditions) and try to catch   
butterflies (or
 something)using this type of forearm motion, see if it improves things.>

This touches upon something that's puzzled me for a while about the   
cursorial theory of the origin of flight.  As the feathered arms of the   
cursorial dinosaurian ancestor of birds were exapted/selected for flight,   
their contribution to prey capture must have declined. The "capture   
cone"---the forward area within the reach of a running bipedal dinosaur's   
hands and mouth---would have been reduced as selection on the arms and   
hands became more for aerodynamic function than for prey capture.

My own theory about this is that the feet may have taken over the role of   
the hands in prey capture as the arms became more dedicated to flight. As   
a hypothesis for this, I would suggest that the evolution of the reversed   
hallux (development of grasping ability by the feet) and the   
carpometacarpus (loss of grasping ability in the hands) are related   
evolutionary innovations.