This year marks the 150th anniversary of the birth of Charles Darwin (Feb. 17, 1809) and the centenary of the publication of his Origin of Species (November, 1859); in this carefully documented book on the great naturalist and his contemporaries the author asks: ""Why was it given to Darwin, less ambitious, less imaginative, less learned than many of his colleagues, to discover the theory (of natural selection and evolution) sought for by others? Was he a great revolutionary? If so, what was the nature of the revolution he brought about?"" Answering these questions she tells of Darwin's family and early life and his 5-year voyage to South America in the ship Beagle during which, studying fossils, he began to question, as other scientists were doing, the then accepted theory of ""Permanence of Species"". After years of experiment and study he formulated his theory of evolution which, published in the Origin, brought forth incredibly bitter controversy from scientists and churchmen alike. Presupposing on the part of her readers a knowledge of its basic facts, the author writes at length of this conflict, its revolutionary results, and of the scientists and clerics who fought in it. Long, clearly written, with extensive bibliography and notes, the book will hold small appeal to non-scientific readers, but Darwinians, naturalists and students of evolution and species-mutuations will find it invaluable. It belongs in all scientific collections.