The heart-shaped face of this ant soldier of the Atta laevigata species allows room for muscles that power her scissorlike mouthparts. While she stands ready to bite attackers, other workers use equally impressive mouthparts to slice up leaves to nourish their gardens of edible fungus.
Ancient ants developed farming some 50 million years ago, long before people, says Ted Schultz of the Smithsonian Institution in Washington, D.C.