In a modern retelling of one of Aesop's fables, researchers in England have shown that members of the crow family can use tools to retrieve a worm that they wouldn't otherwise be able to reach.
In "The Crow and the Pitcher," Aesop wrote of a thirsty bird confronted with a half-full pitcher of water. When the bird discovered that the water level was too low to reach, he dropped stones in to raise the level until it was high enough to quench his thirst.
Aptly named zoologist Christopher David Bird of University of Cambridge showed that rooks, members of the crow family, could perform the same task, dropping stones into a tall glass beaker to retrieve a floating wax worm.
The results, reported this week in the journal Current Biology, are not totally unexpected: Crows have previously been shown to use leaves and sticks as probes to dig out grubs, and shells and rocks as hammers to break open prey or as plugs to form pools of water for drinking.