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This is Scientific American's 60-Second Science. I'm Wayt Gibbs. Got a minute?

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Planthoppers are tiny insects, only a couple of millimeters long.

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But man can they jump.

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An adult planthopper can sweep its two hindlegs together to spring forward more than a meter,

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the equivalent of you or I leaping over tall buildings in a single bound.

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But these superjumpers must push off with both legs at almost exactly the same time, or else they'll go into a spin and wipe out.

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A new study reports that the planthopper Issus coleoptratus evolved a foolproof solution to this problem:

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in young nymphs of the species, the two legs meet under the belly in plates fringed with interlocking teeth.

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They function just like mechanical gears.

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The work appears in the journal Science.

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As the bug cocks its two hindlegs forward and then thrusts them back to push off, those gears guarantee that both limbs complete their motions within 30 millionths of a second of each other.

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The synchronized forces propel the nymph straight through the air at up to nine miles an hour, impressive.

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But adult planthoppers can jump at more than 12 miles an hour.

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And they do it using smooth-rimmed hips, with only friction to keep their legs in sync.

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So perhaps the gears are like training wheels, just there until the youngsters learn how to jump straight.

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Thanks for the minute, for Scientific American 60-Second Science. I'm Wayt Gibbs.

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