Lead researcher Dr Tania Singer said: “Men expressed more desire for revenge and seemed to feel satisfaction when unfair people were given what they perceived as deserved physical punishment.
“This type of behaviour has probably been crucial in the evolution of society as the majority of people in a group are motivated to punish those who cheat on the rest.
“This altruistic behaviour means that people tend to protect each other against being exploited by society’s free-loaders, and evolution has probably seeded this sense of justice and moral duty into our brains.”
In a study published in the Proceedings of the Royal Academy (January 17, 2006), Keith Jensen and colleagues from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany looks at altruism and spite in our close cousin; the chimpanzee. In JensenÃ¢â‚¬â„¢s study, chimpanzees from the Wolfgang Koehler Primate Research Centre in Leipzig were given a choice; by pulling on a rope they could either deliver food to another chimpanzee or they could deliver it to an empty room. In both cases, the chimpanzee pulling the rope did not receive any food itself. Contrary to initial expectations the chimpanzees behaved neither altruistic nor spiteful. According to the researchers, both characteristics therefore seem to be human-specific.
An altruistic chimpanzee would give food to its neighbour, despite the effort in pulling the food, and a spiteful chimpanzee would prevent its neighbour from having the food by delivering it to the empty room.
Ã¢â‚¬ËœI predicted chimps would be spiteful. I thought if they knew they couldnÃ¢â‚¬â„¢t have the food, they wouldnÃ¢â‚¬â„¢t let anyone else have it.Ã¢â‚¬â„¢ Jensen found that half the time, the chimpanzees did nothing. A quarter of the time they delivered food to their neighbour, then a quarter of the time to the empty room. This demonstrated neither altruism nor spite.
Ã¢â‚¬ËœThey didnÃ¢â‚¬â„¢t seem to care about the other guy one way or the other. All that concerned them was getting the food and they were completely focused on that. Even when they knew they couldnÃ¢â‚¬â„¢t have the food, they didnÃ¢â‚¬â„¢t help the other chimp but they werenÃ¢â‚¬â„¢t spiteful either.Ã¢â‚¬â„¢
If altruism and spite are unique to humans and are not present in chimpanzees, then it is likely that these characteristics have arisen in the last 6 million years since humans and chimpanzees shared a common ancestor.