Why beans 'jump'

MEXICAN jumping beans do not jump into the air, but rock or sometimes scoot a millimetre or two.

MEXICAN jumping beans do not jump into the air, but rock or sometimes scoot a millimetre or two.

The thing that makes them jump are tiny moth larvae that live inside the beans. They lay eggs in the flower of the plant and eggs are incorporated into the seeds. They eat out the interior of the bean and live there. When the larvae move, so does the bean. Eventually, they turn into moths, emerge from the beans and repeat the cycle. - howstuffworks.com

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