Guest KC Huang is many things: A bioengineer. A microbiologist. An inventor. But mostly he’s an expert on the ecology of the human gut. He and his collaborators have developed a device that can sample bacterial DNA and create a living map of the gut microbiome from mouth to … ah, well … you know. Every step of the way, he says, we play host to trillions of guests we know very little about. It’s time we got to know them, Huang tells host Russ Altman on this episode of Stanford Engineering’s The Future of Everything podcast.