Book excerpt: What is morality and what is the source of our moral ideas? Philosophers have explored these questions for centuries, suggesting that both emotion and reason play roles but failing to explain how and why Homo sapiens developed these ideas. Author Roger Moseley argues that evolutionary forces that optimize human welfare provide the missing explanation. Morality: A Natural History presents a multi-disciplinary analysis of the topic and reveals a common thread among the seemingly diverse fields of religion, neuroscience, experimental psychology and game theory, child development, evolution and animal behavior, and anthropology and sociology. When humans first appeared, a simple self-interested survival morality sufficed. As societies became more complex, however, rules of behavior became necessary to limit conflict and promote cooperation. The brain evolved, producing language that allowed the articulation of moral ideas which were codified and enforced by religion and social forces. No species lasts forever, and it is at our peril today that we neglect those evolved moral values of cooperation, altruism, truthfulness, and empathy. Rooted in scientific evidence and interspersed with personal anecdotes and humorous observations, Moseley provides a unique perspective on the natural history of morality – how it appeared, evolved, and continues to evolve today. Morality: A Natural History is essential reading for academics and laypersons alike who seek to understand the origin and essence of human morality.