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RE: Arms into wings



<So, don't look at the forelimbs of shrews etc. to get a glimpse at the
condition in the ancestors of bats, when those of other archontans   
probably
give us a much closer glimpse.>

My point remains, however, that you shouldn't look at bats to get a   
glimpse of the prey capturing function of forelimbs in bird ancestors.

<Sure they did: *AFTER* they had become ornithothoracines! However, the   
hands of _Archaeopteryx_ and even _Confusciusornis_ retained quite a bit   
of grasping ability (as various morphometric and morphological studies   
have suggested).  After all, there are few morphological differences   
between the forelimbs of Archie and dromaeosaurids.>

I guess I'm suggesting that overall function of the arm and hand as prey   
capturing devices must have been compromised over time once selection   
began acting to improve aerodynamic performance.  If you are running   
after a dragonfly and flapping, you can't also be grabbing for it with   
your hands-- at least not without breaking the flapping rhythm. The   
process involved a fundamental shift in the function of the arms and   
hands from prey capture to flight. The carpometacarpus was simply the   
coup de grace.