Our health, body shape, mood and even our evolution are determined by the unseen life forms that swarm throughout our bodies. There are worms in your bowels, bacteria in your mouth, fungi in your lungs and viruses in your DNA. The combined genetic information of all these bugs is 150 times greater than our own genes. This collective menagerie is called the micro-biome, and in a very real sense, it is the making of us all.