We are a cooperative ape, and a fair one. We work together to put food on the table and once it’s there, social rules compel us to share it around equitably. These two actions are tied to one another. In a new study, Katharina Hamann from the Max Planck Institute for Evolutionary Anthropology has shown that three-year-old children are more likely to fairly divide their spoils with other kids if they’ve worked together to get them.

The same can’t be said of chimpanzees, one of our closest relatives. Sharing comes less naturally to them, and it doesn’t become any more likely if they’ve worked together to get a meal.

Hamann says, “Among great apes, only humans are true collaborative foragers.” Other species might look for food together, but being next to one another is not the same as working together. The only exception are the hunting parties of chimps, where several individuals work together to kill monkeys for food. The slain monkeys are shared, but either under duress or in exchange for favours.

With children, things are very different. Studies have shown that children as young as five to seven start ...