The Economist: Games in Biology and Economics

When discussing the outcomes of these games, animal behaviourists speak of “evolutionarily stable strategies”, with the implication that the way they are played has been hard-wired into the participants by the processes of natural selection. Economists prefer to talk of Nash equilibria and, since economics is founded on the idea of rational human choice, the implication is that people will adjust their behaviour (whether consciously or unconsciously is slightly ambiguous) in order to maximise their gains. But a study just published in the Proceedings of the National Academy of Sciences, by Robert Kurzban of the University of Pennsylvania and Daniel Houser of George Mason University in Fairfax, Virginia, calls the economists' underlying assumption into question. This study suggests that it may be fruitful to work with the idea that human behaviour, too, can sometimes be governed by evolutionarily stable strategies.