There's an invisible world of microbes living all around us — on our skin, in our guts, even in the ground beneath our feet — and we're only just beginning to understand their function. In this episode, recorded live at the 2019 American Association for Advancement of Sciences (AAAS) Meeting in D.C., we interview two scientists who are using genetic data to study the "microbiome" of soil. Turns out, these tiny organisms can help us answer big questions about agriculture, energy, climate, and much more.