Posted: 09/22/2009 09:37:32 PM PDT
Q. Birds aren't suddenly flying faster than they used to, so how did we just get a new "fastest bird," looking like "a little magenta fireball dropping out of the sky"?
A. With a new mode of speed analysis using not feet or meters per second but body lengths per second (blps), says Susan Milius in "Science News." During courtship displays, the male Anna's hummingbird dives from on high, whizzing past a female so fast his tail feathers chirp in the wind.
As he pulls up to avoid crashing, he experiences forces greater than nine times the force of gravity, more than any known vertebrate stunt flier outside a cockpit.
When zoologist Chris Clark of the University of California, Berkeley, analyzed the dives, he found that, adjusted for body length, the hummingbird's speed reached 385 blps, easily topping the 200 blps of the peregrine falcon.
"A fighter jet with its afterburners on reaches 150 blps and a space shuttle screaming down through the atmosphere hits 207 blps."