bird flight

["Ken Carpenter" <Kcarpenter@dmns.org>]

In watching the documentary "Winged Migration" (briefly discussed previously on 
the DML), I note that the wing tips of various birds do not move in the exact 
same pattern (I use wing tip simply because it is an easy reference point to 
trace bird wing movement). Although closely related birds have similar wing tip 
movement patterns, more distantly related birds don't. This got me wondering if 
the "one-size-fits-all" model of bird flight is correct. The tremendeous 
variation in wing shape (long, tapering of gliders, versus short, broad of 
flappers) would suggest that there may be more subtle variation in wing 
movement than realized. Certainly the variation in humeral heads among birds 
suggests that this may be so. The standard model of bird wing motion is the 
figure "8". In some footage in the flm of a duck flapping its wings a little, 
the wing tip clearly did not move through the figure 8, rather it seemed to 
move in a "O" at the most. Perhaps bird flight needs a new assessme!
 nt!
 (graduate students: hint, hint). 
Kenneth Carpenter