"When he discovered "Lucy," the oldest skeleton of any erect-walking human ancestor ever found, Donald Johanson made headlines all over the world." "Johanson, author of Lucy: The Beginnings of Humankind, the controversial bestseller that altered the science of anthropology, is now the preeminent authority on human evolution. In Ancestors, his most ambitious work to date, Johanson calls on both extensive, hands-on field-work and current scientific...