Can crows outsmart your seven-year-old kid? It’s a close call

Turns out, they can both hold a grudge.
Derya Ozdemir

Crows are fascinating creatures -- watch one make its way through a bustling city and you'll see how it uses the traffic to open hard-to-crack nuts. They are well-known for being among the smartest animals in the animal kingdom; yet, the more you learn about them, the more awestruck you will be by the depth of their brilliance.

In fact, a study has found that crows' reasoning ability rivals that of seven-year-old humans. A startup has even trained crows to pick up cigarette butts from city streets by rewarding them with food for every butt they deliver.

Crows are known to be incredibly intelligent and have a strong memory, with studies indicating that they can recognize and remember individual human faces. Crows may also keep grudges and pass them to their kids, which is why you should never meddle with the crows in your neighborhood.