Monkey Kind, Monkey See, Monkey Know

When monkeys help another monkey, they know it.

“When given the option either to drink juice from a tube themselves or to give the juice away to a neighbour, the test monkeys would mostly keep the drink. But when the choice was between giving the juice to the neighbour or neither monkey receiving it, the choosing monkey would frequently opt to give the drink to the other monkey,” according to an article at



The significant discovery was not the act itself, however. It was finding that an area of the brain responded only when a monkey not only gave the drink to another but also watched the neighbor drink it. Steve Chang and his colleagues from Duke University conducted the study reported in Nature Neuroscience in 2013.

Through the development of a part of the brain that experiences the reward of helping others, empathy-like processes may have been favoured during evolution in primates to allow altruistic behaviour. “This may have evolved originally to promote being nice to family, since they share genes, and later friends, for reciprocal benefits,” says Michael Platt,  a co-author of the paper.

For humans, these incentives for generosity have encouraged our capacity for kindness so much that we can be kind even t0 strangers—and even if they are out of sight. Unlike monkeys, we don’t need to witness a hungry member of our species eating our donation of food. It is enough that we can imagine it, and we choose to do that in part because it is pleasurable.

This holds true even though our remote giving has its limitations. Donations to organizations, for example, may not reach those we intend to reach, and even if the donations do get there, they may not prove very useful. But we donate anyway because the experience of generosity is so powerful.

We may sometimes look down on the act of giving to others simply because it feels good. Shouldn’t altruism be motivated more by duty and justice? But this study suggests that we have good reason to respect our pleasurable response. It is our ancient participation in one of evolution’s more benevolent survival strategies. .