Yvonne Baskin



Soil, which has been called the "poor man's rain forest," faces ecological pressures of its own. A spade of rich garden soil may harbor more species than the entire Amazon nurtures above ground. Two-thirds of Earth's biological diversity lives in soil and underwater sediment, a micromenagerie that includes uncataloged millions of bacteria and fungi, but also tiny nematodes, copepods, wingless insects called springtails and their better-known cousins: mites, beetles, snails, shrimp, termites, pill bugs and earthworms.