We all love the idea of equal pay for equal work.  But who would have thought that monkeys would grasp that idea as quickly as we do?  Two monkeys are given a simple task: hand over a rock.  When they do, they are rewarded with food.  Cucumber slices for one, and grapes for the other.

It only takes one time for the cucumber monkey to get pissed off.

By the way, this is how every scientific experiment should be presented.  It's funny, and doesn't get bogged down with tech-speak.  I wish I'd has classes with that guy as a professor!