Prof. David Montgomery is a geomorphologist   environmentalist in the Earth and Space Sciences division at the University of Washington’s College of the Environment. He specializes in the evolution of geological topography and the influence of geomorphological processes on ecological systems and human societies. His research has taken him world wide, the Cascade Range in the Pacific Northwest to the Andes, the Himalayas and Tibetan plateau.  Joining him is his wife Anne Bikle, a biologist and environmental planner whose work includes watershed restoration and advancing public health through environmental initiatives.  David has author several important works, including “Dirt: The Erosion of Civilizations”, and together their most recent book is “The Hidden Half of Nature: The Microbial Roots of Life and Health” that exposes the critical role the microbiomes in our soil and in our guts play to sustain life and health. Their website is Dig2Grow.com