Chimps have 'sense of fair play'

[Godless Dave]

Chimpanzees display a similar sense of fairness to humans, one which is shaped by social relationships, experts claim.
They found that, like humans, chimps react to unfairness in various ways depending on their social situation.

Details of the study appear in the journal Proceedings of the Royal Society B: Biological Sciences.

A similar finding has been reported in capuchin monkeys, suggesting that a sense of fairness may have a long evolutionary history in primates.

From http://news.bbc.co.uk/2/hi/science/nature/4207351.stm

[JoeP]

This sounded at first like research I've heard of before (possibly from Stephen Jay Gould) on altruism and punishment for misdeeds - actions of an individual in a tribe that go against the social order (I think this was in primates too). But thinking about it, it's something different yet related. Apart from the structure of the tongue and vocal chords that allow to articulate so may different phonemes and so build a more complex language, there's not so much that's unique about humans.