No matter what we do, however kind or generous our deeds may seen, a hidden motive of selfishness lurks - or so science has claimed for years. This book tells readers differently. The authors demonstrate that unselfish behaviour is in fact an important feature of both biological and human nature. Their book provides a panoramic view of altruism throughout the animal kingdom - from self-sacrificing parasites to insects that subsume in the superorganism of a colony to the human capacity for selflessness - even as it explains the evolutionary sense of such behaviour.