An excellent argument that evolution applies to culture as well as organisms.
"A masterful educator, David Sloan Wilson begins with basics and then carefully amplifies them. To understand any product of evolution (a hand, cancer, aggression), one must address four areas: function, history, mechanism, and how it develops. A snowflake may be more complex than a hand, but it doesn’t qualify because it has no function. The problem of evil torments theologians but yields to evolutionary analysis. Thus, altruism seems a trait for wimps because selfish individuals prosper, but a group where everyone cooperates always outcompetes a group with selfish members. The author emphasizes that cultural evolution is a multilevel process. A learned behavior spreads by benefiting individuals compared to other individuals in the same group or the whole group compared to competing groups."
Book Review: This View of Life, Completing the Darwinian Revolution