No book has changed our understanding of ourselves more than Darwin's Origin of Species. It caused a sensation on its first day of publication in 1859 and went on to become an international bestseller. The idea that living things gradually evolve through natural selection profoundly shocked its Victorian readers, calling into question what had been for many the unshakeable belief that there was a Creator. In this book, Janet Browne, Charles Darwin's foremost biographer, shows why Darwin's Origin of Species can fairly claim to be the greatest science book ever published. She describes the genesis of Darwin's theories, explains how they were initially received and examines why they remain so contentious today. Her book is a marvellously readable account of the work that altered forever our knowledge of what it is to be human.