Scientists Have Decoded Bat Language — Here’s What They’re Saying

Photo: Ewen Charlton/Getty Images

Bats’ image as a species may be on the upswing — a report published earlier this year on “historically stigmatized species” found that they’re not nearly as hated as they were a few decades ago — but they’re still not yet considered cute enough to attract the sort of attention that other, more cuddly animals typically get: A recent study on animal cuteness and research funding sorted them into the “ugly” category. A burn, maybe, but not an undeserved one.

This particular story, though, is one of brains triumphing over beauty: Creepy though they may be, bats are actually among the most sophisticated communicators in the animal kingdom, according to a study published last week in the journal Scientific Reports. Individual bat calls are difficult for the naked human ear to detect — “Basically [it’s] bats shouting at each other,” study co-author Yossi Yovel, a zoologist at Tel Aviv University and the head of the school’s Bat Lab for Neuro-Ecology, told The Guardian — but closer analysis reveals highly specific meanings: “We have shown that a big bulk of bat vocalisations that previously were thought to all mean the same thing, something like ‘Get out of here!’ actually contain a lot of information.”

Yovel and his colleagues recorded the sounds made by a group of 22 Egyptian fruit bats over the course of several months. They also took video of the same time period, combing through the footage to figure out which noises corresponded to four different types of aggression: disagreements over food, mating attempts, space to sleep, and space to perch while awake. The researchers then fed just under 15,000 of the bat calls they’d collected into a voice-recognition algorithm, which sorted the sounds by situation. Around 60 percent were successfully categorized into one of the four types of interaction they’d identified.

And within each type of call, the researchers found, were additional layers of nuance: “The animals made slightly different sounds when communicating with different individuals. This was especially true when a bat addressed another of the opposite sex — perhaps in a similar way, the authors say, to when humans use different tones of voice for different listeners,” Nature reported. “Only a few other species, such as dolphins and some monkeys, are known to specifically address other individuals rather than to broadcast generalized sounds, such as alarm calls.” Bats may not be the prettiest ones in the bunch, but they’re still members of a pretty exclusive club.

Scientists Have Decoded Bat Language