All For One? Why Humans Cooperate

Feb. 16, 2005 — -- Despite the fact that humans sometimes fight fiercely among themselves, one of our most distinctive human traits is our willingness to cooperate with others. Why we are like that is one of the really big questions confronting evolutionary psychologists.

"The fact that people cooperate is quite mysterious," says Robert Kurzban, an assistant professor of psychology at the University of Pennsylvania. "People are constantly talking about how organisms are competing, but one thing that humans do that's distinctive is they cooperate in groups."

Other animals, from ants to wolves, also cooperate to a degree, but not as extensively as humans. As evolutionary psychologists, Kurzban and Daniel Houser of George Mason University are trying to figure out why.

Since most people are trying to get ahead in life, it would seem that we are primarily competitors, not cooperators, and while the "big question is still out there," as Kurzban puts it, competition may be a key factor in why we cooperate.

"If I had to make a guess I think it's at least possible that one of the important features behind human cooperative behavior is actually intergroup competition," Kurzban says. "You can't compete in groups unless people are cooperating within groups."

Just ask any coach. If a team doesn't play as a team, it will likely lose, regardless of the talents of individuals within the team.

There's more than a little irony in that because if the individual members of the team are extremely competitive, they'll still lose. So somehow they have to learn to cooperate with each other.

The evolution of that peculiar trait probably contributed to the development of many other human abilities, including the capacity to discuss our needs and our mutual goals.

"If you think about language, what language allows us to do is coordinate our behaviors in ways that other organisms just can't," Kurzban says. "You go over there and stand behind that tree, and I'll come over here and throw this rock, or whatever.