The Mystery of Monogamous Marriage
Monogamous marriage isn't just strange in evolutionary terms, but in relation to human history: Approximately 85 percent of societies known from the anthropological record allowed men to marry multiple wives, and that tendency actually became more pronounced with the advent of agriculture and social complexity.
Why, then, has monogamous marriage prevailed? Psychologist Joseph Henrich of the University of British Columbia thinks it's socially beneficial: If relatively few men will get to marry and reproduce, men will compete fiercely for the chance, and that translates into rape and murder, assault and deception. Monogamous marriage reduces the competition, making communities more stable and -- in terms of cultural evolution -- better able to compete against unstable, non-monogamous communities.
Henrich even posits a link between monogamy and democracy. "Within the anthropological record, there is a statistical linkage between democratic institutions and normative monogamy," he writes.
Image: Derek Garvey/Flickr
Citation: "The puzzle of monogamous marriage." By Joseph Henrich, Robert Boyd and Peter J. Richerson. Philosophical Transactions of the Royal Society B, Vol. 367 No. 1589, March 5, 2012.
