Frans de Waal answers readers' questions on the Freakonomics blog. (HT: Michael Perry, Mirror of Justice).

I think de Waal is really interesting and I've learned a lot from him. I especially recommend Chimpanzee Politics and Good Natured.

I briefly discuss de Waal's work (especially his analysis of reciprocal altruism in "Good Natured") in my essay on "Evolutionary Psychology and The Social Science" in the Humane Studies Review a few years ago.