Steve Connor: Hunter-gatherers are more forgiving

Highly-paid bankers and NHS managers are feeling the wrath of the public's sense of fair play. Their salaries, many times higher than the lowest-paid workers in banks and hospitals, are seen as unfair. If the public could vote on it, there is little doubt that they would vote overwhelmingly to cut these salaries down to size and even to penalise these people for past excesses.

Punishing people who do not play fair is in fact a widely observed psychological trait in modern societies. Indeed, a sense of "fair play" is by no means unique to Britain because many studies have shown that a substantial proportion of people in industrialised societies around the world are happy to punish unfairness.

These studies are carried out using punishment games such as the "dictator game", when the individual participant or "dictator" is matched against an anonymous partner. In these games, scientists can judge how willing someone is to punish unfairness, as well as engage in acts of altruism towards their unknown partner.

One such study, recently published in Science, looked at people's willingness to punish unfairness in non-industrialised societies, such as people living as traditional hunter-gatherers, marine foragers and pastoralists. Intriguingly, Joseph Henrich of the University of British Columbia and colleagues found that people in these small communities were less likely to punish any unfairness shown by an anonymous participant in the game compared to people in advanced, industrialised societies.

The crucial thing here is the anonymity of the participant. People living traditional lifestyles in small communities, which is how humans have lived for more than 95 per cent of their evolutionary history, feel there is no need to punish acts of unfairness shown by anonymous participants – but they have a strong sense of fair play when it comes to people they know personally.

What this shows is that the sense of fair play we see in big, industrialised societies has in fact been shaped by the norms and institutions that have emerged as a result of economic development. In other words, a sense of fair play is not just some innate trait built into our genes as a result of living in small, traditional communities. In complex societies it evolves to the point where we feel it is important to punish unknown people for acts of unfairness. This is why we feel the urge to punish highly-paid executives we do not know personally.

Species on the brink

Extinction is a natural part of life on earth. But we are living in a period when species are going extinct at a rate that is many times higher than the "background" rate. Some estimates suggest that it could be between 100 and 1,000 times faster than usual, largely because of changes caused by human activities, notably habitat destruction and activities such as hunting and over fishing.

With this in mind, the World Conservation Society has just published its "rarest of the rare" list of most endangered species. Some animals, such as the Grenada dove – the national bird of the Caribbean island – has suffered from loss of its habitat. Others, such as the ploughshare tortoise of Madagascar, with just 400 left in the wild, is threatened by the illegal pet trade.

It is a sad fact that as things get rarer, they also get more valuable to collectors.