Do you play fair?

In evolutionary terms the closest living species to human beings are the great apes: chimpanzees, gorillas and orang-utans. The physical similarities are obvious, sometimes all too obvious, but most humans rest comfortably on a sense of superiority that they have “higher” minds than the apes. Where apes are brutish and cruel, humans are altruistic and kind; aren’t they? Well according to a new study it seems that chimpanzees at least share one high-minded trait with human beings: a sense of fairness.

The researchers in this study used a game called the Ultimatum Game, which is used to measure fairness in humans. The game is based on a premise that involves one individual proposing a division of a reward to another individual, however the division does not take place at all unless the two individuals accept the division. In humans the first person usually offers 50 per cent of the reward to their partner.

In this study the researchers gave a modified form of the Ultimatum Game to adult chimpanzees and human children aged 2-7 years. The rewards in the game were food for the chimpanzees and stickers for the children. In this modified form of the game, the first individual in a pair was able to choose one of two tokens. One token would mean an even distribution of rewards with a partner, while another token meant the individual making the choice would receive more. The chooser of the token had to hand the token to their partner, who then had to hand the token to the experimenter, who would dispense reward accordingly. So, effectively, both partners had to agree to the token that was chosen.

The chimpanzees behaved exactly the same as the children, and as you would expect adult humans to behave. When the partner’s co-operation was required, the first partner chose a token that would split rewards equally. However, when the partner had no chance to reject the offer then both chimpanzees and children chose the more selfish option.

From an evolutionary perspective, it makes sense that social creatures would develop a sense of fair distribution in order to reap the benefits of being part of a larger group. Alas, for both chimps and humans, it seems that fairness only goes as far as it must. True fairness surely comes when you don’t have to offer it, and that is the mark of an evolved being.