Crows can count and they do it out loud

We knew crows were smart but it turns out they can also do math. Well, they can count. And they do it out loud. A new study from the University of Tübingen in Germany has revealed that crows can count out loud. They caw as they count. Insert Counting Crows joke here.

"Producing a specific number of vocalizations with purpose requires a sophisticated combination of numerical abilities and vocal control,"  write the neuroscientists in a scientific paper. "Whether this capacity exists in animals other than humans is yet unknown. We show that crows can flexibly produce variable numbers of one to four vocalizations in response to arbitrary cues associated with numerical values."

To be clear, quite a few animals—even honeybees—understand numbers, but as Science Alert reports, counting out loud "requires not only that understanding, but purposeful vocal control with the aim of communication."

The researchers trained three carrion crows (Corvus corone) to respond to symbols or audio cues by cawing a specific number of times, between one and four. When the crows were done, they pecked a target to indicate completion.

"The findings suggest that the birds are capable of using a non-symbolic approximate number system, showing a level of vocal control that mirrors the early counting skills of human toddlers," they write.

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