German scientists in Tübingen and Konstanz have discovered that, high above our heads, bats are not only using echolocation to find food — they're using it to talk amongst themselves. And they could even be calling each other by name.
In a study published in the PLoS Computational Biology, Yossi Yovel, Mariana Laura Melcon, Matthias O. Franz, Annette Denzinger and Hans-Ulrich Schnitzler show that the greater mouse-eared bat (native to Europe, where myths about bats taking human form originated) use their echolocation skills not just to navigate, but to communicate. In their paper, the scientists write:
We used a direct paradigm to show that greater mouse-eared bats (Myotis myotis) can easily discriminate between individuals based on their echolocation calls and that they can generalize their knowledge to discriminate new individuals that they were not trained to recognize. We conclude that, despite their high variability, broadband bat-echolocation calls contain individual-specific information that is sufficient for recognition. An analysis of the call spectra showed that formant-related features are suitable cues for individual recognition.
In slightly less academic language, each bat has a unique "voice," which is recognized by other bats and used for decision-making.
Scientists have wondered for quite a while whether bats were just speaking in a language humans couldn't hear:
Researchers were always fascinated by the social behaviors exhibited by bats. There are, for instance, some reports of bats leaving the roost and flying to and between foraging sites in groups of between two and six individuals. Little is known about how bats might perform the strenuous task of remaining in a group when flying at high speeds in darkness, or about how they avoid interference between each others' echolocation calls. The finding that bats can recognize their conspecifics based on their echolocation calls might have some significant implications in this context.
Yeah, like, if we can start listening in to their code, perhaps we can find out where their master is located and drive a stake through his heart.
The Voice of Bats: How Greater Mouse-eared Bats Recognize Individuals Based on Their Echolocation Calls [PLoS Computational Biology]
Image via naturgucker.de]