Incorporating recent discoveries that have been filling in our family tree at an unprecedented clip, Sloan, paleobiology specialist at National Geographic Magazine, retraces both human physical evolution over the past seven or so million years, and the parallel but far more recent cultural evolution that brought us from flaked stone tools to agriculture in a relative eyeblink. Supported by dazzling graphics, along with an array of spectacular illustrations that include striking full-face digital reconstructions of ancient ancestors, he carefully analyzes surviving evidence, judiciously presents current controversies, and closes with cautionary comments on our modern diets, life expectancy, and environmental changes. Equally suited to quick skimming or careful study, this systematic look at our deep past delivers compelling insights into our origins and behavior. (index, lists of books and Web sites) (Nonfiction. 10+)