My profile of the work of Laurie Santos, director of the Comparative Cognition Lab at Yale, appears in this month's issue of the APS Observer. Laurie studies capuchin monkeys to understand why humans often display such irrational economic behavior:

Capuchins broke off the human line roughly 35 million years ago; as a result, they share many of our complicated cognitive strategies, yet they remain isolated from the linguistic, cultural, and technological systems that might corrupt human decision making. From the perspective of someone studying irrational economic biases, the monkeys offer an excellent means of distinguishing learned behaviors from natural ones. They provide, as Santos says, a “really great window” into human behavior of old. In study after study in recent years, that window has shown Santos and her collaborators that capuchins indeed repeat many of the economic mistakes once considered unique to mankind — from loss aversion to the endowment effect to certain risk behaviors — suggesting that these irrational tendencies are a long-held, fundamental phenomenon.