Bats can Recognize Voices Of Their Partners

Bats can recognize other bats by the kind of sounds they make, a new study from Germany has found.

The study was conducted by Hanna Kastein from the University of Veterinary Medicine in Hannover, Germany, and her colleagues, who found that False Vampire bats, Megaderma lyra, have individualized relationships, meaning that bats possess an ability to recognize each other by sound patterns. Bats are already known to recognize each other via body contact.

Researchers said that this ability to identify a bat based on sound can lead to members of a particular group staying together at night roosts.

The study is published in the journal Animal Cognition.                    

In the study, researchers observed the behavior of two sets of bats which were kept in different rooms. The study team first observed the bats based on body contacts and then recorded the contact calls made by these bats when they were separated from their groups.

Researchers then played these sounds back to the bats which were either body-contact partners. Also, researchers played contact calls of non-body contact bats and unknown bats from other groups. The team then observed how a bat would react after hearing the sounds of its partner or a stranger. They measured the bats' behavior by assessing their reactions and body movement when the sound was being played via a loudspeaker.

Initially, the temporarily separated bat responded to contact calls of all bats equally. However, when the bat was presented with the contact call of a known bat for a long time and then was presented with a call from an unknown bat, the isolated bat was more likely to be responsive to the calls of its partner. Researchers found that bats can assess a sound individually.

"The experiments provide evidence for identity discrimination based on voice dissimilarity, and may indicate recognition of conspecifics by voice," researchers said.