November 10, 2011
Hummingbirds Shake Their Heads To Stay Dry
Researchers from University of California - Berkeley have revealed that hummingbirds shake their heads to get rid of water when it rains.The team used slow-motion footage to reveal how a hummingbird copes with rainy weather. The cameras show that the bird shakes it head with acceleration that can reach a g-force of 34.
"It is the extreme mobility - its head is going through 180 degrees in a 10th of a second or less - it is just extraordinary," Professor Robert Dudley, one of the authors of the study, said in a statement.
The hummingbird has been known to live in cloud forests and neo-tropics, working through wet conditions. However, researchers were unsure how the birds were able to remain active even in the rainy weather.
The team used hi-tech cameras on a bird as it fed from its feeder while having water sprinkled on it.
"We simulated three different types of rain - and the hummingbirds did this extreme oscillation in light, medium and heavy rain," Dr Victor Ortega-Jimenez, from the University of California - Berkeley, said in a press release. "It seems it is a common behavior of hummingbirds."
The team said they were surprised that the birds were able to generate the force while in flight.
"We know visual information is the key to flight control, and, obviously, when you are shaking your head, you don't have that input of flight acceleration, and yet they remain basically stable - they are not falling out of the air," Dudley said.
The findings were reported in the journal of the Royal Society Interface.
On the Net: