As we give thanks for sustenance this holiday season, we might tip our hats to the life-supporting organisms living beneath our feet. Virtually all that we eat, from tofurkey to turkey, originates on fertile soil. From a consumer’s point of view, the story of a roasted bird begins at the supermarket, but the first chapter in every animal’s life is one of grass and grain converted to flesh. Fish, too, depend on a delicate food web that begins with land-based nutrients from the soil. Even the word human originates from the Latin humus (“earth”), the moist, loamy, earthy-smelling black matter from which life springs.