Crows can be trained to count out loud much in the way that human toddlers do, a study finds. Andreas Nieder/Universal Images Group Editorial

We have paid crows passing attention, and have not considered them obviously charismatic but always worthy of further consideration:

Crows can count out loud like human toddlers — when they aren’t cheating the test

Math isn’t just a human thing. All kinds of animals, from African grey parrots to chimpanzees, are thought to have some kind of mathematical ability, but it can be hard to test. Now, a new study finds that certain crows have a way with numbers — one that resembles that of human toddlers.

Counting is a skill that children develop in stages. If you present a young toddler with three blocks, the child may well look at them and say, “One, one, one.” Each word acts as a placeholder to refer to one of the blocks, summing to three.

This is an early form of counting, says Diana Liao, a neuroscientist at the University of Tübingen in Germany. The child is keeping track of a quantity of things (in this case, three) by making the same sound several times. This stage appears to be a steppingstone to more sophisticated, adult-like counting.

“A couple months later, when you ask, ‘How many blocks are there on the table?’ the toddler would just respond with, ‘Three,'” says Liao.

The “one, one, one” form of counting requires a toddler to be able to both tally each object with a sound and control the number of sounds they’re making. Liao wanted to know whether this second element — of producing a specific number of vocalizations — is something that other animals can do, too. Her critter of choice to test this question: the carrion crow.

“Crows are great,” she says. “They’re super smart. They’re a lot of fun to work with.”…

Read the whole article here.