The Banana

"Female chimpanzees will 'present' in sexual posture to a male to whisk away his banana when his prandial interest is thus distracted. In another instance, a chimpanzee would fill his mouth with water, coax a disliked keeper over to the cage bars, and spit the water in his face. In both such instances, the deceit involved is a case of instrumental learning, a behavior pattern that is followed by some rewarding state of affairs. And it needs no further explanation." ~ Julian Jaynes.