October 15, 2012

Gagaku: Ancient Japanese Music

Gagaku is the oldest form of classical music in Japan. It thrived in ancient Japanese imperial courts and dates back to the 700s. The tradition of Gagaku music still survives, although the music is rarely performed outside of Japan. Reporter Maria Bakkalapulo attended a performance in Scotland and shared the experience with Soundcloud. Enjoy the free audio track below.

October 6, 2012

Can hummingbirds fly backward?

High speed photo of a hummingbird feeding.
Photo credit: Michael Elliott
If you are wondering if a hummingbird can fly backward as efficiently as it can fly forward, the answer is yes! It might seem to take a lot of energy for a bird to move backward, but hummingbirds often fly in reverse. A new study from the Max Planck Institute for Ornithology reports that a hummingbird's backward flight is almost as efficient as its forward flight. Hummingbirds can fly backward in an upright position at up to 10 miles per hour. Below is an excerpt from the New York Times summary of the study.

“When they are flying backwards they have a very upright body posture,” said Nir Sapir, an avian ecologist affiliated with the Max Planck Institute for Ornithology in Germany and one of the researchers involved in the study. “We thought they might have a much higher drag, and invest much more energy in flight.” 
Dr. Sapir worked on the study when he was a postdoctoral researcher at the University of California, Berkeley. He and his colleague Robert Dudley, a researcher at the Smithsonian Tropical Research Institute in Panama, reported their findings in The Journal of Experimental Biology
Dr. Sapir captured five Anna’s hummingbirds outside his laboratory and trained them to fly in a wind tunnel and feed on a syringe of sucrose disguised as a flower.
As they fed, Dr. Sapir turned on the air in the tunnel so that the birds had to fly backward to remain at the flower. He repeated the experiment with the feeder rotated 180 degrees so that the birds had to fly forward to keep feeding.
When flying forward, the birds beat their wings about 39.7 hertz. When they flew backward, they beat their wings only slightly faster, at 43.8 hertz. The rate of oxygen consumption was also similar, Dr. Sapir said.