Re: How did dromaeosaurs use their arms?

[Dinogeorge@aol.com]

In a message dated 5/9/00 7:26:13 AM EST, qilongia@yahoo.com writes:

<< Such a structure would allow the wrist to
 fold easily against the forearm, pulling it out of the
 way, and allowing sufficient leverage for a powerful
 forward "swap" of the hand, to be simplistic. >>

This is the key feature of dromaeosaurid forelimb anatomy that supports the 
Greg Paul/BCF thesis that dromaeosaurids are secondarily flightless. There is 
virtually no chance that such a specifically winglike forelimb articulation 
would have evolved in a grounded cursorial predator. But once it is 
understood as a holdover from a common ancestor that used its forelimbs for 
flying--and that the forward "swap" of the hand you describe is a relic of 
the wing stroke in the flying ancestor--its appearance in dromaeosaurids and 
other maniraptoran theropods becomes clear.