Combining thoughtful science with sheer fun, this book is impossible to put down... this book deserves wide attention. - Publishers Weekly I shall never feel the same about ducks again. Or fish. This is first class science told with brilliance and flair. Read and be astounded. - Robyn Williams John Long is renowned as the discoverer of the earliest evidence for internal fertilisation. In a book encompassing 380 million years of sexual evolution, he lays the full significance of his discoveries in fascinating context. - Tim Flannery You know that any book on evolutionary theory that opens with the story of erotic asphyxiation-strangling your sex partner to deplete oxygen to heighten orgasmic intensity-and how even a normal orgasm is so intense as to simulate a mini death through a momentary loss of consciousness at the point of climax, is going to be a great read. And so it is in this marvelously entertaining and remarkably informative book on the evolution of sex by paleontologist John Long, one of the world's leading experts on teasing out of the fossil record the history of sex over the past several hundred million years. This book is erotica for empiricists. - Michael Shermer, Publisher of Skeptic magazine, monthly columnist for Scientific American, adjunct professor at Claremont Graduate University, and the author of Why Darwin Matters and The Believing Brain.