For decades now, man has modeled their methods of flight from the majestic bird species that have conquered the skies. But what if there's a glitch in birds' programming that remains hidden in the secrets of aviation?
In nature, the hummingbird may be small, but they have an impressive grace and an even more impressive speed. By beating their wings back and forth hundreds of times per minute, the mighty hummingbird is able to fly in place like a helicopter. And though their methods may seem effective to the outside observer, a new study published this Monday Dec. 8 in the journal Proceedings of the National Academy of Sciences reveals that there may be an issue in the hummingbird's internal software that encodes for the "hover in front of food" protocol they adhere to so well.
Researchers from the University of British Columbia, Benjamin Goller and Douglas Altshuler, investigated the tiny bird species to see whether or not the fast-flappers could become distracted in the presence of another flapping object in flight. And what the study found was that some of the fast-flappers lose in-flight energy and momentum to stay afloat when background motion is present in their peripheral field-of-view.
"Relatively little is known about how sensory information is used for controlling flight in birds. A powerful method is to immerse an animal in a dynamic virtual reality environment to examine behavioral responses" Goller says. "Here, we investigated the role of vision during free-flight hovering in hummingbirds to determine how optic flow is used to control body position."
In order to test their hypothesis, researchers projected images on the surface behind the birds' feeders in the lab to create a distraction that could potentially alter the hummingbirds' motion. As hummingbirds attempted to come in for a sweet snack of nectar, the scientists set the rotating spiral in motion, which in turn caused the birds to fly more haltingly and lose their focus on food in the process.
"Despite the urge to feed, the birds seemed unable to adapt to the moving images" Goller says.
And without the ability to adapt over time, even when they grew used to the presence of the moving images, the hummingbirds revealed that the peripheral view and competing movement can indeed flummox the little flyers into a bit of a downward spiral.
But, in comparison, still images left in their peripheries did not cause a physiological response when the hummingbirds sought out their nearby nectar. Researchers concluded that hummingbirds may hover in position by stabilizing movement in their visual field, much like a ballerina is able to pirouette for minutes on end by spotting her turns against a stationary object or wall. The process, the researchers say, is surprisingly sensitive in the species known for spatial mapping and an acute ability for visual processing.
"It suggests the hummingbirds' visual motion detection network can override even a critical behavior like feeding."
