Moral behavior in animals

Recently came through following interesting video where a monkey angrily rejects unequal pay:

[W]e did a study in which capuchin monkeys received either a grape or a piece of cucumber for a simple task.

If both monkeys got the same reward, there never was a problem. Grapes are by far preferred (as real primates, like us, they go for sugar content), but even if both received cucumber, they’d perform the task many times in a row.

However, if they received different rewards, the one who got the short end of the stick would begin to waver in its responses, and very soon start a rebellion by either refusing to perform the task or refusing to eat the cucumber.

This is an “irrational” response in the sense that if profit-maximizing is what life (and economics) is about, one should always take what one can get. Monkeys will always accept and eat a piece of cucumber whenever we give it to them, but apparently not when their partner is getting a better deal. In humans, this reaction is known as “inequity aversion

Here’s a full talk from de Waal at Ted, where he shares some surprising results of behavioral tests on primates and other mammals, which show how many moral traits like empathy and cooperation all of us share. Talk was recorded 4 November 2011.

So the next time you feel you’re being unfairly compensated, or feel the broader sting of income inequality, you can say to your friends, “I feel just like a monkey who’s been given a cucumber while the monkey next door got a grape,” and thanks to Frans de Waal they will know what you are talking about.

Bonus: