Exploring what they call "the ancient propensity of life to mix itself productively, creatively, surprisingly", the authors range broadly and brilliantly over such disciplines as comparative primatology, microbiology, and linguistics as they attempt to explain the mysteries and marvels of the sexual impulse.Necessary to survival, sex is an obsession -- the root of all kinds of animal behavior from romance to aggression. Sex excites our bodies and transfixes our imaginations, making us realize that we need each other just to be. What Is Sex? takes readers on a fascinating billion-year journey through all of the permutations that the subject holds: the origins of gender, the sexual strategies of life forms from mitochondria to humans, the language of sexual display and deception. Luminously written, gloriously illustrated, and marked with the credibility that only a world-class scientist and her award-winning collaborator can grant, What Is Sex? is an exuberant, provocative, splendidly original work.