Many of life's building blocks can be found in the objects bombarding Earth from outer space. Does that mean that life, too, developed elsewhere before arriving here? Mary P. Hrybyk-Keith/NASA hide caption

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Mary P. Hrybyk-Keith/NASA

For centuries, Russians believed putting a brown frog in their milk would keep it fresh. Now scientists are finding chemicals in the frog's slimy goo that inhibit the growth of bacteria and fungi. Stefan Arendt/Corbis hide caption

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Stefan Arendt/Corbis

Moss and a cup fungus growing amid the decomposing leaves of Shakerag Hollow in Sewanee, Tennessee. Courtesy of David Haskell hide caption

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Courtesy of David Haskell

Kids' Sugar Cravings Might Be Biological

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