It’s all around us. It lies beneath our feet, it gets embedded in our clothing and skin, and the air is filled with it. It makes us sneeze. Great clouds of the stuff are lifted from the African Sahara by harmattans and sciroccos and carried high into the atmosphere, where great westward-flowing aerial rivers carry it across the Atlantic to South America, where it falls like rain and feeds the equatorial rainforest. Weird, right? I’m talking, of course, about soil, or as most of us call it, dirt.

This is the first part of a two-part series on soil and what lives in it. Enjoy.