Mental exercise for chimpanzees

Obviously humans are not the only ones that experience pleasure when riddling. Also chimpanzees like to puzzle, even without getting a reward. This was found out by two scientists in Whipsnade Zoo north of London when they wanted to test the effect of enrichment on the well-being of the animals. It was surprising that the game without reward was even more popular than the one where the chimpanzees got nuts in the end. To have fun and to experience satisfaction was enough motivation.

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