Children and parrot and songbird chicks share a rare talent: They can mimic the sounds that adults of their species make. Now, researchers have discovered this vocal learning skill in baby Egyptian fruit bats (Rousettus aegyptiacus, pictured), a highly social species found from Africa to Pakistan. Only a handful of other mammals, including cetaceans and certain insectivorous bats, are vocal learners. The adult fruit bats have a rich vocal repertoire of mouselike squeaks and chatter (listen to a recording here), and the scientists suspected the bat pups had to learn these sounds. To find out, they placed baby bats with their mothers in isolation chambers for 5 months and made video and audio recordings of each pair. Lacking any other adults to vocalize to, the mothers were silent, and their babies made only isolation calls and babbling sounds, the researchers report today in Science Advances. As a control, the team raised another group of bat pups with their mothers and fathers, who chattered to each other. Soon, the control pups’ babbling gave way to specific sounds that matched those of their mothers. But the isolated pups quickly overcame the vocal gap after the scientists united both sets of bats—suggesting that unlike many songbird species (and more like humans), the fruit bats don’t have a limited period for vocal learning. Although the bats’ vocal learning is simple compared with that of humans, it could provide a useful model for understanding the evolution of language, the scientists say.
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