Just Like Dogs, Bats 'Waggle' Their Heads Too -- Here's Why

A new research says that bats also waggle their heads back and forth to listen for coming insects. The study claimed that by waggling their heads, bats can locate their prey, especially if the movements of their prey are becoming irregular.

"The sound is going to be hitting the ears in different ways throughout that dynamic process, and it's those differences the bats exploit," said study author Melville Wohlgemuth, a postdoctoral researcher at Johns Hopkins University in Baltimore, via Live Science.

The study, which was published in the journal PLOS Biology, mentioned that Wohlgemuth and his colleagues want to find out the ways how brain assimilates auditory information and vocalizations.

Bats are known for capturing prey by echolocation, which is a bio sonar, where they create sounds that then bounce off solid objects like insects.When bats hear the echoes, they will adjust their movements and vocalizations to get their prey. Animals that have echolocation "calls out to the environment" and then listen to the echoes that bounce back to them. Through hearing the echoes, the bats can now adjust their movements so that they can catch their prey.

For this experiment, the researchers trained big brown bats (Eptesicus fuscus) to hunt in a more casual way. This means that the bats just sit in a platform while the researchers present them preys by putting it in fishing wires, letting them approach the bats in different movements.

It was found out that as the prey approaches, the bats waggle their heads back and forth. The researchers also observed that the bat's head motion becomes more frequent as their prey's movement becomes more and more complicated. And when the bat's prey suddenly changes its directions, the bat's head waggles more.

Many animals, including humans, tilt their heads while trying to locate sounds that they hear. Dogs, cats and even owls do it too. Bats are no exception. But what makes bats different is that they have striking hearing and localization capabilities. Usually, the brains of animals with two ears use information to determine how a sound hits the ears to know where it came from.

Tech Times notes that how important movements are because it help them to improve the signals that are utilized by the senses. The researchers observed that other animals that use active sensing to focus on important information are similar with bats.

"This finding also highlights the general importance of movement to sensory processing across animal species. Finally, our discoveries point to important parallels between spatial perception by echolocation and vision," the researchers concluded.