Monkey Business: Fairness Isn't Just A Human Trait : NPR: "Showing your humanity usually refers to an act of kindness or charity. Treating someone humanely means treating him fairly and with dignity. But are these traits really unique to humans?
Psychologist Sarah Brosnan wants to find out. She argues that traits like fairness and curiosity are essential for any social animals to survive and live together. To show that, Brosnan works with capuchin monkeys at the Language Research Center, a part of Georgia State University.
The capuchins here are 'living in a normal social environment,” she says. 'So they spend the vast majority of their day out here running around playing together, and we just separate them out for the testing.”
The monkeys climb over branches in the cage, swing from the top of the cage, wrestle with each other. When it's time for testing, the animals go indoors."