QUOTE : Hunter-gatherers are generally spared opportunistic leadership because the gap between rich and poor is so narrow—not surprising in economies that don't use currency or stockpile food. As soon as food can be monopolized, though, hunter-gatherers become just as unfair and stratified as everyone else. Archaeological evidence from across the Pacific Northwest indicates that some Native communities figured out how to restrict access to riverine salmon fisheries and quickly institute a powerful elite that built large houses, kept slaves, and passed wealth from generation to generation. But most Native peoples lived off the land in a way that could not be monopolized. A survey of several hundred tribes native to North America found that nearly 90 percent of the ones with no large food surpluses also had no political inequality. Conversely, social stratification was found in almost 90 percent of tribes that did stockpile food or monopolize its production.