How Humans Overcame Violence and Volatility When They Transitioned From Nomadic Bands to Large Settlements

Managing the strain of group living and thwarting the Young Male Syndrome

“By obeying one’s xing and going along with one’s emotions, one must set forth in robbery and contention…Thus there must be the transformation brought about by the…Way of ritual and morality; only then will one set forth in deference and courtesy, accord with refinement and principles, and come home to order.”

—Xunzi (3rd century BCE)

Homo sapiens are thought to have first appeared roughly three hundred thousand years ago. For ninety-seven percent of human history, people lived in small hunter-gatherer societies, comprised of approximately 150 people.

Then, about 10,000-12,000 years ago, with the rise of the agricultural revolution, humans transitioned from nomadic groups in search of food to stationary villages in which they cultivated their own crops, domesticated livestock, and produced their own food. The size of communities expanded.

But what did this actually look like? How did humans manage the transition from small hunter-gatherer groups to large permanent settlements?

A new paper from the eminent Oxford evolutionary psychologist Robin Dunbar examines these questions.

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Large group size appears to pose risks to both survival and reproduction.

Across primate species, within-group violence tends to increase as groups grow larger. More individuals reduces the odds of survival. Much of this is due to competition for food, resources, and status.

For instance, among the !Kung San (modern hunter-gatherers), serious disputes arose every 2-3 weeks at large waterholes that attracted 100-150 people. But such disputes only arose every 3-4 months at smaller waterholes where only 30-50 individuals gathered.

Similarly, in modern cities, increasing levels of crowding and household density have detrimental effects on physical and mental health, and are associated with increases in violence and homicide.

Moreover, among mammals, as the number of individuals in a group increases (especially young females), fertility rates tend to decline. Researchers have suggested that this appears to be due to stress that coincides with female-female interactions, with access to food or resources playing little to no role in fertility rates. Dunbar states that “these psycho-social stress effects appear to be a more serious limitation on group size than more conventional ecological constraints.”

Still, humans have managed to form large group settlements. The paper suggests that early humans cultivated social cohesion through a variety of innovative practices, which had two benefits:

• Defense against external threats (e.g., predators and out-group violence)

• Mitigate social stressors (e.g., within-group violence and conflict)

For example, San Bushmen (modern hunter-gatherers) will occasionally engage in a dance to dispel what they call “star sickness.” This mysterious force encompasses jealousy, anger, interpersonal conflicts, and a failure to exchange gifts. Such pressures give rise to hostilities and damage cohesion in the group.

Many nomadic hunter-gatherers adopt a “fission-fusion” system to reduce social stress. This entails dispersing the community (typically around 150 individuals) into several smaller groups of 30-50 people.

Hutterites, for example, split their communities to maintain their size below 150 members.

This is because, Dunbar notes, they understand that larger communities require formal mechanisms such as laws, a judiciary, and a police force. In contrast, small communities can be run by strictly democratic means, face-to-face discussion, peer pressure, and a sense of personal obligation.

Dispersing into smaller bands enables individuals and families to move between the groups when social interactions become overly contentious.

However, Dunbar, points out:

“Once a community switches into permanent settlement mode, it will face escalating stresses that, if unalleviated, will inexorably result in increasing costs (competition for resources, longer foraging journeys, greater difficulty in achieving consensus over management decisions, and an increasing frequency of disputes with risk of these spilling over into violence).”

He goes on to write that large settlements are only possible “if solutions can be found that defuse these stresses and encourage good behavior.”

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One challenge to overcome involves the behavioral tendencies of young males.

Dunbar writes:

“When males (and younger males, in particular) are deprived of social, economic, and mating opportunities, they are prone to behaving in ways that both stress other group members (especially reproductive females) and threaten the stability and cohesion of the group. This is as true of the more social primates as it is of humans, and is often associated with high mortality rates. Under these circumstances, males are also likely to indulge in raiding neighbouring groups, which can result in poor inter-community relations as well as retaliation. Managing male behaviour may, thus, be critical to maintaining an environment conducive to successful reproduction.”

Young males are (unknowingly) experts at disrupting social cohesion. To be fair, they are also required to maintain and defend it. They’re a mixed bag.

Disputes that spill over into violence and homicide have been an ever-present risk in both contemporary and pre-modern small scale societies. Young men make up the overwhelming majority of such conflicts, both as perpetrators and as victims.

Rob Henderson @robkhenderson

The Young Male Syndrome "Homicide is overwhelmingly a male affair...Victim and offender populations are almost identical, with unemployed, unmarried, young men greatly overrepresented...many, perhaps most, homicides concern status competition" sciencedirect.com/science/articl…

Here is a stylized example of the Young Male Syndrome from The Sopranos. Junior mafiosi Christopher Moltisanti enters a bakery and believes (or finds a reason to believe) he is being disrespected by the young guy working the counter.

The vast majority of violence is carried out by young men.

Psychologically, a key reason for this is that women are more sensitive than men to penalties. Men are more inclined to take risks, oblivious to the punishments they may receive. Men also have lower levels of empathy and a higher tolerance for pain.

The psychologist Simon Baron-Cohen has posited the hypothesis of the “extreme male brain,” suggesting that males are at higher risk for a clinical diagnosis of autism because of the constellation of traits men tend to score higher on (e.g., systematizing over empathizing, favoring things over people, etc). It also implies that most males may be a little bit autistic. Of course, some women score highly on these traits, and there are girls and women who are diagnosed with autism. Just at much lower rates than males.

I have wondered if, in addition to autism, the idea of the “extreme male brain,” could just as easily apply to psychopathy.

For both psychopathy and autism, the ratio of males to females is about three to 1.

Men (especially young men) are more pronounced than women on just about every trait that characterizes psychopathy.

Relatively low impulse control, low empathy, low fear, high sensation seeking, relatively shallow emotions, need for stimulation, proneness to boredom, violent fantasies, desire for revenge, and increased likelihood of criminality. Of course, some women score highly on these traits, and there are women who are psychopaths. But far fewer than males.

The psychologist John Barry has pointed out that when he was a student, he learned he couldn’t use standard adult psychopathy tests to administer to teenage boys. The reason? Because adult tests might give teen males a false positive.

Just as (relative to women) most men might be a little bit autistic, most (young) men might be a little bit psychopathic.

On average, a twenty-five year old man has the same level of impulse control as a 10 year old girl.

Source

Many people ask why so many violent crimes occur, I tend to think the opposite: It’s stunning how little violence there is. Though for what it’s worth, only about half of all violent crimes are reported to the police.

Fortunately, many men age out of it. Dark Triad personality traits peak in adolescence and early adulthood, and decline thereafter.

Dunbar cites historical and archaeological records indicating stunning levels of violence in humanity’s past.

For instance, internal conflicts among Viking communities in the 9th-12th centuries in Iceland were so severe that in one case, all of the adult males in one quarter of extended families were slaughtered.

Among Australian Aboriginal groups in the nineteenth century, revenge killings were frequent, and typically associated with accusations of witchcraft (these were aimed at both men and women). Dunbar suggests one likely explanation is that such accusations reflected difficulties individuals had in coping with (and explaining) unexpected illnesses and death that coincided with larger group sizes.

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Dunbar uses homicide rates as a proxy for the levels of social stress and dysfunctionality within a community to test three specific hypotheses:

1. In hunter-gatherer societies, homicide rates increase as group size grows

2. Life in large permanent settlements is only possible if the rate of violent deaths is kept below a certain threshold

3. This is achieved by developing social institutions that mitigate conflict by enhancing a sense of belonging to the community (social cohesion)

Dunbar analyses datasets encompassing 25 small scale societies, as well as drawing on historical and ethnographic studies.

Although warfare has existed throughout human history, the majority of homicides occur within rather than between groups. In part this is simply because people spend more time around fellow group members.

To test whether social institutions enhance a sense of belonging to the community, Dunbar focuses on activities such as religious rituals, feasting, singing, and dancing that have been shown in prior research to enhance social cohesion. He also looks at social innovations that manage the behavior of young males (e.g., men’s clubs, socially recognized leaders). And he analyzes the mechanisms that regulate relationship arrangements (marriage, kinship, dowries). Notably, the paper does not include institutions that are intended as methods of control (e.g., explicitly written laws, courts, formal legal penalties, policing). This is because such innovations tend to arise only in very large societies.

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The paper finds that living in large groups is indeed stressful, as homicide rates increase sharply as the community grows larger.

“The hunter-gatherer data suggest…a limit at around 50 or so on the number of individuals that can live together when there are no formal mechanisms to defuse or manage conflict. At this limit, half of all adult mortality is due to homicide, effectively doubling the rate of mortality from conventional natural causes (i.e., disease, accident, and old age)…an increase in mortality rate of this magnitude would likely push the population below the replacement rate and increase the risk of community extinction.”

Moreover:

“The rate at which these stresses increase appears to be sufficiently steep that all deaths would be the result of violence if the entire community of 100-200 individuals tried to live together as a single group for any length of time. One interesting implication of this is that it implies that the reason hunter-gatherers live in small dispersed groups has less to do with ecology and foraging than with the escalating costs of stress (just as seems to be the case in anthropoid primates).”

In other words, in the absence of formal social mechanisms (religion, community leaders, group bonding activities, etc.), all deaths in a small scale human society would be due to murder.

The implication that hunter gatherer communities disperse into smaller groups not because of resources or ecological reasons, but because of social conflict, is consistent with other findings indicating that the reason human intelligence evolved is not to solve technical problems, but rather to navigate perilous social terrain. This is called the “social brain hypothesis” or the “Machiavellian intelligence hypothesis.” At a certain point in human evolution, the most prominent and serious dangers were no longer the environment or external predators. The real threats were other people.

This might also explain why highly intelligent people are often more susceptible to social pressures and ideological capture. The psychologist Keith Stanovich, in his book The Bias That Divides Us, has written:

“If you are a person of high intelligence...you will be even less likely than the average person to realize you derived your beliefs from the social groups you belong to and because they fit with your psychological propensities.”

Smart people are at least as good at deception, strategic subtext, and social games as they are at reasoning.

Using your immense human brainpower to solve complex technical or ecological problems is like using a butterknife as a screwdriver. It works, but that’s not its intended purpose.

Anyway, humans eventually established large settlements, despite the attendant risks. It appears they did this with structural innovations (religion, men’s organizations, respected community leaders, rituals, and so on) that dampened social stressors.

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The anthropologist Donald Tuzin studied the Ilahita Arapesh, a people living in New Guinea who had integrated 39 clans encompassing more than 2,500 people. The cooperation of this large community was sustained through mutual obligations, reciprocal responsibilities, and social rituals infused with supernatural beliefs. The villagers believed their community’s prosperity was the result of their rituals, which, they believed, pleased their gods.

When cooperation broke down, elders blamed this on members not adhering to the rituals properly and would then call for additional rites better to please their deities. The social bonding resulting from this activity was the mechanism for improving the community’s cohesion. But the assigning the power to the gods gave the rites legitimacy that they otherwise may not have had.

The ancient Confucian disciple Xunzi favored rituals as a way of providing social order. He believed that rituals such as marriage, burial customs, and feasting and drinking brought people together and bonded them into a cohesive community.

Even in secular societies, humans are responsive to the powers of ritual. In his recent book Ritual: How Seemingly Senseless Acts Make Life Worth Living, the experimental anthropologist Dimitris Xygalatas describes a study in which researchers showed participants videos of a man pouring a drink into a glass.

In video, the man performed the ordinary action of picking up a glass, cleaning it with a cloth, pouring the drink, and inspecting it before setting it on a table.

In another video, the event was ritualized: after picking up the glass, he waved the cloth at it without touching it, raised the container high up before pouring it into the glass, and bowed to the glass before setting it on the table.

When the researchers asked participants whether the two glasses were the same in terms of their physical qualities, the participants generally said yes.

But when asked which one was more special, a significant difference emerged: they favored the ritual drink.

When asked which beverage they would prefer to have, participants were three times more likely to pick the “special” drink.

As Xygalatas points out:

“Even though people said that the actions had not changed the object, an important change did occur: their perception of the actions changed, and this in turn changed their behavior towards the object.”

And when participants were told that the gestures were part of a traditional ceremony practiced in Fiji, Gabon, or Ecuador, participants were even more likely to select the ritual drink.  

Perhaps this is why at certain bars, mixologists will perform an impressive series of deliberate movements and seemingly unnecessary actions when making drinks—it makes them seem like they are worth more.

Anyway, as I wrote in this post, rituals clearly have a powerful effect on human psychology. They are among the key social innovations that enhance social cohesion and reduce the probability of violence.

In addition to religious rituals, socially recognized and prestigious leaders, as well as men’s associations/clubs are particularly important at larger group sizes.

This may be because disputes between males can easily spiral into reciprocal violence when large numbers of allies can be recruited.

A recent study found that a small scale community in New Guinea  established bachelor clubs to limit and channel the energy and volatility of young adult males.

These clubs help to bond males. Mutual obligations between close friends reduce the likelihood that disagreements escalate into violence.

Moreover, these clubs have elder members, who help to settle disputes through advice and counsel.

The paper also cites research indicating that, at a size of around 400, organized religions tend to arise to cultivate stability and help manage social fractiousness. It’s possible that other communities also tended to arise without such social innovations, but we are not the descendants of those groups. If Dunbar’s research is correct, these groups likely died off either by killing one another and/or by being overrun by more socially cohesive groups.

The social innovations of formalized religion, storytelling, feasting, dancing, singing, laughter, life course ceremonies (e.g., puberty rituals and formal marital rites), sporting contests, and the imposition of social discipline (e.g., hierarchical male clubs) on young men all appear to play important roles in enhancing social bonds and thwarting the likelihood of violence.

In short, the stresses created by living in large groups can rapidly give rise to instability and conflict unless sociocultural mechanisms arise to foster group bonding.