“Baby talk,” or “motherese,” might not be a language with any native speakers, but most humans seem suddenly fluent in it in certain situations. Even if you’ve never heard of the term, you know what “motherese” sounds like—people changing the speed, timbre, and pitch of their voice the way mothers tend to do when talking to their babies, which research has shown facilitates language learning.
Sometimes we even do it to our pets—it feels like instinct to talk to something small and cute that way. And it turns out bats might do something similar. Though we’ve known for a while that other animals vocalize to their young, there hasn’t been any research on whether they also change their voices until recently.
A team of researchers decided to study the vocalizations of the greater sac-winged bat, which has a wide vocal repertoire. They recorded adult female and male bats, as well as their pups, in Central America. After analyzing the recordings, they found that the female adult bats’ voices were a different timbre and pitch when they vocalized to their pups than when they vocalized to other adult bats. The adult male bats also interacted with their pups, but in a different way.
This could mean that the mothers were using something like “motherese” with their pups, but since the sample size was small, we’ll need more research before we can tell. Either way, bats need to be careful— if word gets out about this, they’ll have to do damage control to maintain their spooky image.
