This is the audio to a lecture I gave in March 2011 at the Joint Summit on Translational Science. I argued that one way to make medical advances is to recognize the human body as an ecosystem, made up of thousands of species. The slides are at http://www.slideshare.net/cwzimmer/the-human-jungle-exploring-the-microbiome I explore a lot of the science in this talk at greater length in my book Microcosm: E. Coli and the New Science of Life