The gist: Humans are “survival machines” for replicators, AKA genes. Author Richard Dawkins says replicators explain why humans, animals and plants exist and do so many of the crazy things they do. (For example, gym-tan-laundry.) Yes, The Selfish Gene kind of takes the mystery out of existence and the piss out of religion, but that’s what science is supposed to do — answer questions. Political implications abound. Genes act selfishly to survive. It is in a living being’s nature, therefore, to be selfish; most of what passes for altruism in nature is actually selfishness. Dawkins is looking at you, penguin.