Baby bats babble like babies

[ad_1]

Larger winged bat (Saccopteryx bilineata) babbles. Researchers believe the tiny bats make these sounds to practice their vocal skills, Credit: Michael Stifter

Baby big-winged bats develop vocal skills by babbling in a similar way to infants — a discovery that could help researchers explore the basic neuroscience of how mammals learn to communicate with each other.

“Although there are millions of years of different evolutionary pathways between bats and humans, it is surprising to see such similar vocal behavior lead to the same result – the acquisition of a large vocal repertoire,” says Ahanna Fernandez, an animal behavioral ecologist at the Berlin Museum of Natural History. and co-author of the study, which was published August 19 in Science1.

Research suggests that infants babble to practice speech sounds, which requires fine motor control in their voice boxes. Small songbirds also babble, but there are very few other recorded examples of chattering behavior among animals – bat research is the first to identify babble produced by mammals that are not primates. Like humans, bats need extraordinary control over their vocal organs, because they rely on their calls to navigate, find food through echolocation, and communicate during courtship and mating, Fernandez says.

To understand how young bag-winged bats (Saccopteryx bilineata) learn to communicate, Fernandez and her colleagues recorded 216 delirious episodes in 20 wild bat pups in Costa Rica and Panama. The researchers used ultrasonic acoustic devices to capture individual “syllables” of the pups’ high-pitched cries, and identified the most 25 different syllables heard in the vocal repertoire of adult bats.

The team converted these audio extracts into images called Spectrograms that show the pitch and intensity of the sound over time. This enabled them to look for eight key features that characterize babbling in children, including the repetition of syllables and the rhythm of sounds. Their analysis found that bat babble contains all eight of these features.

Surprisingly, both male and female bats learned and produced the syllables that make up the regional song of the adult males. The authors suggest that females may use their experience in producing these sounds to help them make mating decisions later in life.

“It’s interesting to see the similarities in chatter between bats and humans, given the differences between human language and how bats use their vocalizations,” says Jill Suha, an ethicologist at Duke University in Durham, North Carolina, who studies vocal evolution in songbirds. She adds that the researchers analyzed an “astounding number of passages” without disturbing the bats.

Mirjam Knörnschild, an animal behavioral ecologist at the Berlin Museum of Natural History and co-author of the study, inadvertently discovered the chattering behavior of bats more than 17 years ago, when she was working on her master’s thesis. “You hear these bats and immediately think of them [human] Says. Although she and her colleagues reported these findings in 2006, some scientists were skeptical that the sounds represented real sound. Knörnschild says the new comparison of bat sounds with those of infants should allay these doubts.

She adds that analyzing the brains of young bats could help researchers study the basic processes involved in vocal learning. “Basically these bats are waving a red flag, and they’re telling us, ‘I’m learning now,'” says Knörnschild. “This means we can ask questions like: What is going on in the brain while the bat is babbling? Or, what kind of environment do they need to learn best? “

[ad_2]