Freedom to Riot: On the Evolution of Collective Violence

From London to the Middle East riots have shaken political stability. Why? Is it human nature?

“Imagine you’re on a bus,” explains Vaughan Bell, clinical research psychologist at King’s College London. “It’s full of people and you have to jam into an uncomfortable seat at the back.” Very little connects you with any of the other passengers and it is unlikely you would even give them a second thought.

Suddenly, multiple windows are smashed open and you discover that the bus is under attack by a group of thugs who are trying to steal people’s bags through the broken windows. You very quickly feel a common bond with the other passengers and willingly cooperate with them to help fend off the thieves. Extreme circumstances have pushed you into identifying with the group against a common enemy.

“You didn’t lose your identity,” says Bell, “you gained a new one in reaction to a threat.” As Bell points out in the case of riots, that threat is often excessive force from the police that turns a disgruntled crowd into an angry mob.

This scenario is what psychologists refer to as the Elaborated Social Identity Model of crowd behaviour. Each individual remains a rational actor, but has been primed by natural selection to identify with the group during a period of crisis. This well developed ingroup/outgroup bias is what has allowed our species to be the most cooperative of the primates, but certain conditions have the potential to turn us against our own community. While the psychology of collective behavior may explain why individuals join together once a riot is under way, it doesn’t explain why the riot would begin in the first place. As it turns out, our primate cousins offer a unique insight into this question. Nonhuman primates offer a window into the range of behaviors available to our evolutionary ancestors and the legacy that they have passed down to us.

“Collective violence,” wrote Harvard primatologist Richard Wrangham in the Annals of the New York Academy of Sciences, shows “a common human pattern evident in societies lacking effective central authority, manifested in ethnic riots, blood feuds, lethal raiding, and warfare.” Such aggression, he says, is directly related to that of nonhuman primates and demonstrates a common evolutionary history. As Wrangham earlier wrote in his book Demonic Males: Apes and the Origins of Human Violence, our primate origins “preceded and paved the way for human war, making modern humans the dazed survivors of a continuous, 5-million-year habit of lethal aggression.”

Wrangham is but the latest in a long history of evolutionary scientists to argue that collective violence is an adaptive feature of the human species. However, one of the earliest case studies to reach this same conclusion is actually, in the light of hindsight, a prime example arguing against this contention. By doing so, it offers a unique perspective into the factors that motivate collective violence in human societies and may even offer some clues about how to prevent it.

In his book Social Unrest and Popular Protest in England, John archer demonstrated that rioting between 1780 and 1822 correlated with high wheat prices. Identical findings have been reported recently. The rise in prices combined with the growing income inequality lead to environmental stress.

But what is to blame for such cases of collective violence–nature, or the unnatural conditions of modern life? While there may well be evolved responses that promote collective violence, research in captive primates suggest that these behaviors are heavily influenced by environmental stress. During the past year environmental conditions were just right for the triggering of social discord in our own society and, in the contagion that followed, violence quickly spread among a population predisposed to a shared identity.

For London and the cities throughout North Africa and the Middle East, it appears there was a free choice to riot after all. But the choice didn’t come from the rioters alone, it rose from leaders and policymakers and the larger society as a whole. Riots reveal a colony in discord. Many of us have acknowledged the widening inequality and economic decline of our most impoverished citizens–but we chose to ignore it.

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If you'd like to learn more on the subject see Mass Uprisings in the USSR: Protest and Rebellion in the Post-Stalin Years, Social Unrest and Popular Protest in England, and Demonic Males: Apes and the Origins of Human Violence.

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