Saccopteryx bilineata is known as a communicative member of the sac-winged bat family. These animals use elaborate vocalizations as part of their mating rituals, and their vocal abilities start at a young age. Scientists have now suggested that these bats babble like human infants while they're going through their first stage of language learning. This behavior might indicate that social feedback is a factor in the development of these bats' vocal abilities, just as it is with humans. The findings have been reported in Science.
Study leader and former Smithsonian Tropical Research Institute visiting scientist Ahana Fernandez, PhD, spent years doing field work in Panama and Costa Rica for this investigation. Bats had to be habituated to the presence of the researchers to the point that they would engage in their natural behaviors even with these humans present. This research was conducted with wild animals instead of captive ones, which may have been a major factor this discovery; most research like this is done with animals that live in some kind of facility. By studying bats in the wild, Fernandez learned that when mother bats address their pups, they use a kind of baby talk.
“During my first field season when I spent many hours sitting quietly in front of the animals observing them, I realized that mothers and pups interacted during the babbling practice of pups,” said Fernandez, who is now a researcher at the Museum of Natural History in Berlin. “Especially, mothers were producing a particular call type during pup babbling.”
The pattern of babbling in S. bilineata pups was found to be similar to that of humans; both have similar characteristics, including repeating syllables (reduplication) and babbling on a regular beat (rhythmicity). Fernandez noted that baby bats imitate the adults that teach them. This can give researchers an opportunity to study learning in these animals and how it might be influenced by things like the animals' social environment.
S. bilineata bats are now thought to be the only mammals other than humans that babble and practices vocal imitation. The bats may give us new insights into the evolution of our own language abilities and the development of linguistic skills.