What Does It Mean to Be Human?: Official Companion Book to the Smithsonian National Museum of Natural History's David H. Koch Hall of Human OriginsThis generously illustrated book tells the story of the human family, showing how our species physical traits and behaviors evolved over millions of years as our ancestors adapted to dramatic environmental changes. In What Does It Means to Be Human? Rick Potts, director of the Smithsonians Human Origins Program, and Chris Sloan, National Geographics paleoanthropolgy expert, delve into our distant past to explain when, why, and how we acquired the