The monkeys came from three different groups (it was difficult to find one large group) and had been raised in some degree of captivity.

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When facing a "loss" either way, the monkeys preferred the chance of getting three half of the time--even though the expected payoff in all cases was the same.

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At Corcovado you can find tapirs, jaguars, pumas, anteaters, two-toed and three-toed sloths, golden orb spiders, moon crabs, a diversification of monkeys (including all four types of Costa Rican monkeys, found only in Corcovado), crocodiles, poison dart frogs, pelicans, 220 species of butterflies, scarlet macaws and even the rare and venomous fer-de-lance snake.

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But if ten million monkeys sitting at typewriters can reproduce the works of Shakespeare, it stands to reason that three million bored iPhone owners would push enough buttons to find a backdoor this simple.

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After three months the level of dopamine in their brains had dramatically increased and were similar to those found in younger monkeys.

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