An undated photo released by The University of Cambridge shows a rook, a member of the crow family, as it drops stones into a tube to raise the water level and bring a worm into reach, at the Sub-department of Animal Behaviour at University of Cambridge. In Aesop's fable 'The crow and the pitcher' a thirsty crow uses stones to raise the level of water in a pitcher to quench its thirst. A new study published online Thursday, Aug. 6, 2009 in the journal Current Biology demonstrates that rooks, birds belonging to the corvid, or crow family, are able to solve complex problems using tools and can easily master the same technique demonstrated in Aesop's fable.
(AP Photo/The University of Cambridge)