Crows Appear to Be Able to Count Out Loud

Scientists have long known that crows are smart. But a new study suggests they possess the ability to count out loud—a first for an animal species other than humans, reports Live Science. In fact, the crows appear to be pretty good at it, on par with human toddlers, per Scientific American. In the study published in Science, researchers worked with three crows and found they could reliably count to four with their caws, though they add the birds could likely go higher if need be.

"Producing a specific number of vocalizations with purpose requires a sophisticated combination of numerical abilities and vocal control," the researchers write in the study. "Our results demonstrate that crows can flexibly and deliberately produce an instructed number of vocalizations by using the 'approximate number system,' a nonsymbolic number estimation system shared by humans and animals."

In the test, the researchers presented the carrion crows with four visual cues (colored Arabic numbers) and four auditory cues (the sound of a musical instrument, which is kind of fitting). After a learning curve, the birds were able to figure out how many times to caw when presented with a particular prompt. Scientific American draws a parallel with the birds' abilities—and limitations—to young humans getting a grasp of counting. A "toddler who is asked how many apples are on a tree may answer, 'One, one, one' or 'One, two, three'—producing the number of speech sounds that correspond to the number of objects they see rather than just saying, 'Three.'" The crows did much the same with their caws. (More discoveries stories.)