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

itoggle caption 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

itoggle caption Courtesy of David Haskell