All I can contribute to the commentary on Rufous Hummingbird tail notching
and sound is to note that tail modification is correlated with mechanical
sound-making in snipes and woodcocks. And there are wing modifications in
birds that make mechanical sounds with their wings (some manakins, for
example, and perhaps some hummers). It's the end of the day, and my brain
is wearing out; maybe someone can think of additional examples. I had
always assumed that the Rufous jerked its tail at the bottom of the power
dive to make the stuttering sound. How about some high-speed
cinematography on those hummers?

Dennis Paulson, Director phone: (206) 756-3798
Slater Museum of Natural History fax: (206) 756-3352
University of Puget Sound e-mail: dpaulson at ups.edu
Tacoma, WA 98416