Farming Ants

Leafcutter ants, found in the forests and grasslands of Central and South America, are famous for carrying pieces of leaves many times larger than their own bodies. Long lines of ants can often be seen moving leaves along the forest floor. Surprisingly, however, the ants do not eat these leaves.

Instead, they carry the leaves into their underground nests, where smaller ants chew them into a soft paste. The ants use this paste to grow a special type of fungus, which is their main source of food. In this sense, leafcutter ants are farmers, and they were growing crops millions of years before humans. Their colonies can be enormous. A single nest may contain several million ants, each with a specific job, such as cutting leaves, caring for the fungus, or defending the colony.

Like human farmers, the ants must protect their crops from disease. Scientists have discovered that a harmful fungus sometimes attacks the ants' gardens. To fight it, the ants carry bacteria on their bodies that produce natural chemicals which inhibit the harmful fungus. This discovery has interested medical researchers, who hope that studying the ants may help them find new antibiotics.