Melville Wohlgemuth, a researcher from Johns Hopkins University, noticed that just like dogs, bats exhibit an adorable behavior of cocking their heads to the side, so he set out to know the purpose behind this movement he suspected has something to do with hunting.
The research, which was published in the journal PLOS Biology, revealed that the flying mammals do this when they are targeting their prey.
For the study, Wohlgemuth and colleagues used high-tech recording devices to study big brown bats that hunt in both open and cluttered spaces in the wild. They found that the waggling head and wiggling ear of the animal are in sync with its sonar vocalizations to help it catch prey.
The researchers trained the animals to sit on a platform while tracking a moving prey attached to a fishing line. The researchers then attached reflective markers to the bats' ears and top of the head so they can better monitor the positions of the head and ears as the bats tracked their prey moving in different directions.
Wohlgemuth and colleagues found that the head of the bats waggles at a rate of about one per second when the prey altered its direction. They also observed ear movement when the prey grew closer.
Although the ear twitches are very tiny, these help the bats hear the echoes that they need to track and capture their prey.
Although it is long known that bats use echolocation to hunt, the study is the first to show how the animal's head and ear movements can help it catch its prey.
The findings show how movement can help enhance the signals that are used by senses such as hearing and sight not just in bats but also in other animals and even in humans.
The researchers said that the movements they observed in bats are similar to what is observed in other species that use active sensing to attend to important information. Researchers said that studying these movements can shed light on how it helps animals sense their environment.
"Our results demonstrate that purposeful control over sonar sound production and reception can serve to improve acoustic cues for localization tasks," the researchers wrote in their study, which was published on Sept. 8.
"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."
