SCIENCE

The Enemy Within

Termites are covert destroyers. You don’t hear them or see them until they come swarming out of the woodwork on their spectacular mating flight

Richard Conniff

September 30, 1998

Homeowners think of termites as pests, and they are. In this country alone, they cost an estimated $1 billion to $2 billion a year in damage, prevention and control. But they are also one of the most beneficial groups of insects on earth. Like bees and ants, they have evolved an elaborate social system based on cooperation. The 2,300 known termite species nest on every continent except Antarctica and eat not just wood but soil, detritus and dry grass. In fact, termites in Africa consume more grass than all the savanna mammals combined.

Termites are master builders. These grass-eaters create mounds up to 15 feet tall with complex interiors that enable them to cultivate fungus. The fungus is used to break down dry grass, burning off carbon. Much like the human lung, the mounds draw oxygen in from the outside and expel carbon gases. Abandoned mounds are colonized by plants and eventually become forests. Thus do termites enrich the world even as they plunder homes and other buildings.