Fairness, marmosets, and the oldest profession

My girlfriend and I were walking back from a coffee shop today when we decided to stop by the Wisconsin National Primate Research Center (the WNPRC) to see the marmosets housed near the entrance. Apparently, the WNPRC is one of the biggest primate research centers in the country, hosting research on everything from monkey sex to Killer Ig-Like Receptor haplotypes (I'm not exactly sure what those are, but they sound awesome!). However, the building itself is rather nondescript, so I had never actually stopped to see what was there.

What I discovered is that marmosets are freaking adorable.


Seriously. Look at that face.

While this post is mostly designed as a vehicle to post shameless amounts of adorable, I thought I might discuss a bit of the awesome primate research that's happening right now, particularly with respect to the subject of fairness.

Although humans exhibit cooperation on a scale unprecedented in the remainder of the animal kingdom, other animals exhibit smaller-scale cooperation. For example, chimps exhibit food-sharing behavior, with some female chimps apparently giving sex in exchange (evidence that prostitution really is the oldest profession?). Therefore, there is reason to suspect that other human social traits that enhance cooperation, such as a sense of fairness, may be found among in a less developed form among our closest evolutionary kin.

As researcher Frans de Waal summarizes in the summer 2006 issue of the journal Social Research, this is indeed the case. De Waal and his colleagues have found that capuchin monkeys will not only reward others with food for receiving help on a cooperative task, they will protest upon being treated unequally. When two capuchins in full sight of each other are given the opportunity to trade stones for cucumbers, they will both happily do so. However, if, after several successful exchanges of stones for cucumbers, one capuchin is given the preferred reward of a grape instead of a cucumber, the other will suddenly refuse to accept the cucumber or to participate in the exchange at all. Apparently, Republican complaints comparing welfare checks to free handouts may have an evolutionary basis.

And now, MORE ADORABLE!!!

Reference:

De Waal, F. (2006). Joint ventures require joint payoffs: Fairness among primates. Social Research, 73, 349-364.