Tracing the development of population genetics through the writings of such luminaries as Darwin, Galton, Pearson, Fisher, Haldane, and Wright, William B. Provine sheds light on this complex field as well as its bearing on other branches of biology. In a new afterword that is sure to stir discussion and controversy, Provine discusses how his beliefs about evolutionary biology have changed radically in the past 30 years. He examines the 10 major assumptions in the field that were current when the book was first published and then, point-by-point, argues against them in light of more recent research. The result is a work that is at once imbued with new life and yet remains the definitive short history of a major development in modern biology.