{"fact":"Crows demonstrate an understanding of cause and effect, using stones to raise the water level in a container to reach a floating worm, just like in Aesop's fable!","context":"Bird and Emery found that rooks that had experience of dropping stones, but not in the context of water, would spontaneously put the stones into the tube to raise the water level within beak reach and thereby obtain the worm.","source":"Nicola S. Clayton, EPS Mid-Career Award 2013: Ways of thinking: From crows to children and back again, 10.1080/17470218.2014.943673","index":304}