
A sure sign that I've adapted to England, my country of residence but not birth, is that I find it impossible to jump queues. The mere idea causes me pain. That's despite the fact that queue jumping would save me time and usually draws no more than a few tuts for punishment (another very English behavioural trait). So why do I always patiently wait my turn?

Nobody likes queueing, but most of us do it.
The answer is that I've internalised the elaborate social norm English people have built around queueing. I don't so much follow it because I believe in the practical virtues of queues (though I do), but because I feel emotionally compelled to conform. We're all born with this capacity to internalise social norms, and it's easy to see why: norms are the oil that greases cooperative societies. Without them there would be chaos.
In evolutionary terms, however, there's a missing link. Life didn't start with an innate desire to stick to social rules. Our very early ancestors were out for their own survival. Since evolution through natural selection favours the fittest, it's hard to see how polite individuals who are happy to follow collective rules at their own expense would have survived. The same puzzle surrounds the evolution of any form of cooperation and of altruism. How did our ability to internalise social norms take hold?
A recent study addresses this puzzle using a favourite tool in the area: game theory. The idea is to look at life as a game in which each individual can make certain moves directed by clear rules. Individuals follow specific strategies, and those who do better are more likely to produce offspring than those who don't do so well. If you can describe all this in precise mathematical terms, you can use a computer to simulate thousands of generations and see which strategies die out and which thrive. A strategy that looks silly at first sight, such as sticking to norms that offer no immediate price or punishment, may turn out to be beneficial in the long run and over the generations become entrenched.
Sergey Gavrilets and Peter Richerson's game theoretical model involves lots of groups of hypothetical individuals. During its life time each individual has a number of chances (40 to be precise) to join in some collective action (such as forming a queue) or to refuse (to jump the queue). Since social norms aren't likely to take hold unless they are policed, individuals also get the chance to punish those who didn't take part.
Each time a social action comes around an individual is faced with four choices: take part and punish non-conformists, take part and don't punish them, don't take part and punish, and don't take part and don't punish. Gavrilets and Richerson describe the four choices using two variables: the variable
What's the price of not taking part?
Each of these four possibilities comes with a net pay-off for the individual that picked it. That's just as in real life: not taking part and not punishing norm-breakers might give you some advantage (barge to the front of the queue and grab the best piece) but a punishment (being beaten up) might diminish your gain. Your net pay-off then depends on how the advantage of dodging the norm compares to the disadvantage of punishment. Gavrilets and Richerson worked out a formula that determines the pay-off

Game theory looks at life as a game in which each individual can make certain moves directed by clear rules.

The top image shows how the proportion of individuals using different combinations of x and y changes over the generations. For example, the pink line represents the proportion of individuals using x=0 and y=0, the blue line represents the proportion of individuals using x=1 and y=0, and so on. The bottom image shows how the internalisation parameter n changes over the generations. The intensity of the black colour is proportional to the number of individuals with the corresponding value for n present at a given time. The red line shows the mean value of n. (These plots correspond to a particular combination of parameter values.) Figure from Collective action and the evolution of social norm internalization by Gavrilets and Richerson, published in PNAS.
Many of the simulations had intermediate values of
As all game theoretical models, this one greatly simplifies our behaviour and the world we live in. It does show, however, that it's theoretically possible for the ability to internalise norms to evolve in a society where it was initially very low. Gavrilets and Richerson argue that this ability was "likely a crucial step on the path to large-scale human cooperation".
In our highly evolved society social norms of all shapes and colours have emerged. Some are obviously useful, some appear downright silly. Kate Fox's book Watching the English has an eye-opening collection, particularly for immigrants like me. But even if some norms are strange, we at least have an excuse for our meek observance of them: it's instinctive.
Comments
"We're all born with this
"We're all born with this capacity to internalise social norms" - have you heard of autism?
Good point
Thanks for pointing that out Steven, it's a good point and interesting to think about. I guess what we meant to say is the majority of people are born with this capacity. For those people I know on the spectrum, they explain that they don't instinctively internalise these social norms, but some of them, sometimes out of necessity and sometimes out of choice, teach themselves how to follow these. We'll have a think about it and perhaps amend the article.