Chimps understand right and wrong and has been observed that they react only when one of their troop is harmed. The behavior is known as the “Bystander effect”
Researchers watched how a chimpanzees react to viewing a video of a baby chimp from outside their own group being killed, offers a sense of how human morality and social systems have evolved. The death of innocent people is always reported to be much more important if they are from a group or nation that you are attached to.
The studies were undertaken by the University of Zurich in Switzerland. The lead author of the study published in Springer’s journal Human Nature, Claudia Rudolf von Rohr, said it supplies evidence that chimps like us, are sensitive to whether the kind of behavior being observed is appropriate to a situation. It also shows that these primates may only be moved to take action if it is a member of their own group being threatened, which is similar to humans. Bystanders will watch someone being robbed on public transport, but if it was exactly the same scenario and involved someone from their direct social group, they would intervene.
The team of researchers videoed two social groups of chimps living in two gardens within a Swiss zoo, and the animals repeatedly watched video clips. The video’s showed the actions of other chimpanzees who were unknown to them. The control video showed chimpanzees performing regular activities including walking and eating nuts. The experiment video’s showed aggressive situations such as an infant chimp being killed by its own kind, the killing of a Colobus monkey by chimpanzees and grown up chimps being socially aggressive to each other. The video taped periods were assessed for how long the chimpanzees looked at the TV, whether they were excited by what they had seen and how they then behaved as a result.
The chimps watched up to 4X longer when the infant scenes were on the screens compared to any of the other videos. The chimpanzees didn’t just observe these scenes for longer, but gave much increased levels of attention to what was going on.
The work showed that chimpanzees could differentiate between aggressive behavior to towards the young and adult chimps who were also experiencing harmful behavior. It also indicated that incidents of this kind don’t match expectations of tolerance normally given towards the young. This showed a kind of so-called proto social norms at work – where individuals will behave as bystanders to a violation of a certain expectation of how others should behave.
Claudia Rudolf von Rohr, said “The results suggest that chimpanzees detect norm violations both within their group as well as in a group of unfamiliar individuals, but that they will only respond emotionally to such norm violations within their own group,”.
The study is helping us to establish the evidence for the building blocks that create human morality from our closest living relatives. The behavior demonstrated also included consoling and policing.