Crows can count up to four, a new study finds

Perhaps 'birdbrained' isn’t such an insult after all –– crows, the ubiquitous urban bird, can vocally count up to four, the latest research has found.

Perhaps “birdbrained” isn’t such an insult after all –– crows, the ubiquitous urban bird, can vocally count up to four, the latest research has found.

Not only can the inquisitive creatures count, but they can match the number of calls they make when shown a numeral, according to a new study, led by a team of researchers with the University of Tübingen’s animal physiology lab in Germany.

The way the birds recognize and react to numbers is similar to a process we humans use, both to learn to count as toddlers and quickly recognize how many objects we’re looking at. The findings, published Thursday in the journal Science, deepen our growing understanding of crow intelligence.

“Humans do not have a monopoly on skills such as numerical thinking, abstraction, tool manufacture, and planning ahead,” said animal cognition expert Heather Williams via email. “No one should be surprised that crows are ‘smart.’” Williams, a professor of biology at Williams College in Massachusetts, was not involved in the study.

In the animal kingdom, counting isn’t limited to crows. Chimpanzees have been taught to count in numerical order and understand the value of numerals, much like young children. In attempting to woo mates, some male frogs count the number of calls from competing males to match or even one-up that number when it’s their turn to croak at a female. Scientists have even theorized that ants retrace their paths back to their colonies by counting their steps, though the method isn’t always accurate.

What this latest study showed is that crows, like young humans, can learn to associate numerals with values –– and count out loud accordingly.

The research was inspired by toddlers learning to count, said lead study author Diana Liao, a neurobiologist and senior researcher at the Tübingen lab. Toddlers use the words of numbers to tally the number of objects in front of them: If they see three toys in front of them, their counting could sound like “one, two, three” or “one, one, one.”