Some might be surprised to see a simple crow display such ingenuity. If you've ever read "The Crow and the Pitcher," one of Aesop's Fables, you might not be, though. The fable has inspired other literature, but also scientific study.
Pliny the Elder, a Roman author and naturalist who lived during the first century AD, first recorded this kind of behavior in corvids (the crow family). Nearly 2,000 years later, ethologist Nicola Clayton also used the fable as the basis of her study, which greatly furthered the breadth of knowledge surrounding avian intelligence. She observed similar, clever behavior even in corvids who are not closely related, showing that they had developed such cognition much earlier than first thought.