Video: Monkey angrily rejects unequal pay

(CBS News) We don't expect animals to understand human "inventions" like economics. Pay scale, income inequality, surely these are concepts too advanced for lower species to process. Or are they?

The above video, part of a TED talk given by Emory University's Dr. Frans de Waal, showcases the emotional reaction of one Capuchin monkey when confronted with unequal pay for equal work. The work, in this case, is giving a rock to a researcher in exchange for a treat. The monkey is perfectly happy trading a rock for a piece of cucumber, until a neighboring monkey gets a delicious grape for performing the same action.

The monkey's reaction speaks for itself.

Dr. de Waal has made a name for himself by investigating the social intelligence of primates. His work has compared the morality and social skills of primates to humans, often with surprising results. "This is basically the Wall Street protest that you see right here," Dr. de Waal jokes at the end of the video.