Night Crawler Chemistry

Abstract

This year is the International Year of Soils, so designated by the United Nations. Don’t worry if you didn’t know that. Many people don’t think about soil, or even know what it’s made up of or how its inhabitants are vital to its health—and by extension to our survival. What Leonardo da Vinci said some 500 years ago is still true today: “We know more about the movement of celestial bodies than about the soil underfoot.” Of course, scientists have since learned something about Earth’s epidermis. They have classified thousands of soil types by their mineral compositions and now know that soils are full of bacteria, fungi, protozoans, nematodes, insects, and the random mole, gopher tortoise, or burrowing owl. But less well understood is how soils are processed and remodeled by an often-overlooked subterranean chemical engineer: the earthworm. Researchers are still trying to fully understand the outsized role earthworms play ...