DIRT BOILS WITH LIFE. Roots, nematodes, ants, termites, worms, moles, voles and snakes tunnel underground. They search one another out in the dark, chasing mates and food by touch and scent. This subterranean world is nearly invisible to us. We see it in glimpses: A mole falls out of a clay bank and we pick it up in the road, or we dig a hole and watch as unearthed insects scramble to disappear.
The soil is also one of the least-known habitats on Earth. Even underneath a suburban lawn, most organisms are unstudied, and many are unnamed. The citronella-scented orange ant Acanthomyops claviger, for example, is one of the most abundant ants in the northeastern United States. But because it only comes above ground once a year to mate, nearly nothing is known about the species. Only a handful of corpulent queens have ever been seen. Each has been revealed by the lucky turn of a stone or log.