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BOB HIRSHON (host):
The flight of the hummingbird…I’m Bob Hirshon and this is Science Update.
Unlike other birds, hummingbirds can fly backwards. They have to in order to back out of the flowers they gather nectar from. UC Berkeley avian ecologists Nir Sapir and Robert Dudley used high-speed cameras and flower-shaped oxygen masks to study hummingbird flight and metabolism. Sapir says they were surprised to discover that while the tiny birds increase their wing flapping rate while flying backwards, they expend no more energy than when flying forwards. But flying backwards does slow them down.
NIR SAPIR (UC Berkeley / Max Planck Institute for Ornithology):
They can’t fly backwards as fast as they fly forwards, they can go up to a bit less than about half their maximal speed that they can go for forward flight.
He adds that the hummingbirds’ posture becomes more upright during backwards flight in order to move their wings backwards instead of forwards. The research appears in the Journal of Experimental Biology. I’m Bob Hirshon for AAAS, the science society.
Video: BackwardRetreatFlight: A hummingbird flies backward to retreat from a simulated flower. (Credit: Nir Sapir/UC Berkeley)
To learn more about this research, visit: https://jeb.biologists.org/content/215/20/3603.abstract