"Evolutionary biologist Richard Dawkins, for example, might be a bit less certain in his gloomy assessment of human nature: "Be warned that if you wish, as I do, to build a society in which individuals cooperate generously and unselfishly towards a common good, you can expect little help from biological nature. Let us try to teach generosity and altruism, because we are born selfish."10 Maybe, but cooperation runs deep in our species too. Recent findings in comparative primate intelligence have led researchers Vanessa Woods and Brian Hare to wonder whether an impulse toward cooperation might actually be the key to our species-defining intelligence. They write, "Instead of getting a jump start with the most intelligent hominids surviving to produce the next generation, as is often suggested, it may have been the more sociable hominids--because they were better at solving problems together--who achieved a higher level of fitness and allowed selection to favor more sophisticated problem-solving over time."11 Humans got smart, they hypothesize, because our ancestors learned to cooperate. Innately selfish or not, the effects of food provisioning and habitat depletion on both wild chimpanzees and human foragers suggest that Dawkins and others who argue that humans are innately aggressive, selfish beasts should be careful about citing these chimp data in support of their case. Human groups tend to respond to food surplus and storage with behavior like that observed in chimps: heightened hierarchical social organization, intergroup violence, territorial perimeter defense, and Machiavellian alliances. In other words, humans--like chimps--tend to fight when there's something worth fighting over. But for most of prehistory, there was no food surplus to win or lose and no home base to defend."