By the authors of Cosmos, this is an exploration of who we are, and how we were shaped by life's adventure on earth, by a mysterious past that we are only just beinning to piece together. It takes the reader back to the birth of the sun and its planets, and the first stirrings of life; to the origins of traits central to our current predicament; sex and violence, love and altruism, hierarchy, consciousness, language, technology and morality.