Sure enough, when they trained a low-ranking monkey to open the container, just as any technical college advertisement will tell you, the new skills translated into a higher income. Roughly an hour after she’d open the container for everyone, she was getting groomed a lot more, as much as a high-ranking monkey, and she no longer had to do hardly any grooming herself. But that was not the most spectacular finding.

Dr. NOE: So what then did, is we got a second low-ranking female, trained her to open a second container with apples in it, and then we saw that the value of the first provider dropped, more or less, to the half of what she had before. So now we had a competition between two animals. Both of them could provide this good, these apples, and so the value of the first one dropped down again. And of the second one who was very low at the beginning of the experiment, she went up. And they ended up both in the middle, so to speak.

BLUMBERG: So when there was a monkey monopoly on the skill, the monkeys paid one price. But when it became a duopoly, the price fell to an equilibrium point, about half of what it had been. And this all happened despite the fact that we’re talking about monkeys here. Monkeys can’t do math…