A new study has revealed that the shape of a hummingbird’s beak allows for a “controlled elastic snap” that allows it to snatch up flying insects in a mere fraction of a second -- with greater speed and power than could be achieved by jaw muscles alone.
Hummingbird beaks are built to feed on flowers, but hummingbirds can’t live on nectar alone. To get enough protein and nutrients they need to eat small insects too, said co-author Gregor Yanega of the National Evolutionary Synthesis Centre in Durham, North Carolina.
According to Yanega, as soon as the hummingbird’s beak is maximally bent, it suddenly springs back to its original position and snaps closed.
“Their beaks snap shut in less than a hundredth of a second,” he explained. "It’s fast,” he added.
Part of the trick lies in how the hummingbird’s beak is built, the authors said. While other insect-eating birds such as swifts and nighthawks have a cartilaginous hinge near the base of their beaks, hummingbird beaks are solid bone.
“They’re also incredibly thin,” Yanega said.
“This makes their lower beaks stiff yet springy, like a diving board,” Yanega added.
The researchers’ mathematical model revealed that the downward bend of the hummingbird’s lower beak puts stress on the bone, storing elastic energy which eventually powers its sudden snap closure, explained first author Matthew Smith, now at the Air Force Research Laboratory at Wright-Patterson Air Force Base.
“The extra speed likely leads to greater success in catching insects,” Smith added.
The study will be detailed in the Journal of Theoretical Biology.
