Brainy Beasts

Elephants may never forget, but can they recognize themselves in the mirror? New research says yes. Here's a look at recent studies--and our ratings--of intelligence in the animal kingdom.

ROOKS These crowlike birdbrains are actually problem solvers. Animal behaviorists in Britain found this year that rooks can learn how to get a piece of food out of a trap box.

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ELEPHANTS U.S. zoologists said last week that a study using mirrors shows elephants are self-aware--a trait previously proved only in primates and dolphins

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CHICKENS They may not be the brightest in the barnyard, but they do have self-control. British scientists found last year that if given a bit of food, chickens will opt not to eat it if they know when a greater reward is coming.

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DOLPHINS Flipper? Try Hunter. Scientists have seen bottlenose dolphins, thought to be the smartest marine animals, using sea sponges as fishing tools.

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GORILLAS Researchers in Congo last fall were the first to observe gorillas using tools. The great apes were seen opening nuts with rocks and gauging water depth with sticks.

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