As a girl in England, Jane Goodall dreamed of traveling to Africa to study animals in the wild. In the summer of 1960, her dream brought her to the shores of Lake Tanganyika, to observe the wild chimpanzees at Gombe. Other scientists did not believe that a 26-year-old woman could survive alone in the bush, but Jane Goodall did more than survive. Her work, the longest continuous field study of any living creature, revolutionized the field of primatology. In a break from accepted practice, Goodall assigned the chimps names rather than numbers, because she viewed them as individuals, rather than interchangeable specimens. Over the years, she found chimpanzees engaging in activities that were once thought definitively human, such as tool-making, cooperative hunting and even warfare. After nearly half a century of studying mankind's nearest relation in its natural habitat, Goodall has forced us to re-define our understanding of what it means to be human, and provided a vital insight into the evolution of our own species.