Modern Society As Violent As Tribal Society: Deep Scaling Law Reveals

How are modern humans different from our tribal ancestors? We are more civilized, follow rules, respect each other’s properties and lives and are generally more peaceful and harmonious in co-existence, right? Turns out when the right factors are considered in a comparison, we are just as violent as our ancestors.

Researchers from the University of Notre Dame studied the difference in the number of wars and casualties between old small-scale societies and modern day large societies with a much higher population.

The team of researchers conducted a study that took into account the population of a society as a driving factor behind the size of the army. The size of the war group or the people participating in it determines the number of casualties in the conflict, which is a measure of violence.

The team said in a small population, say of 500 people, the war group would have to be a sizeable chunk of all the inhabitants of the place, whereas in a large society with millions of people, a fraction of the population fights in a war, which reduces the percentage of human casualties.

The team were effectively able to correlate the size of a population to the size of the army.

"Small-scale societies have a high proportion of their people involved in war," Rahul Oka, one of the lead authors of the study and Ford Family Assistant Professor of Anthropology said in a press release on the University of Notre Dame website .

"Fatalities might actually be 40 to 50 percent of the group, and definitely a higher proportion of those fighting get killed. But as we go from small-scale societies to big states and conflicts between empires or nations, fatalities rarely go above 1 percent of the group populations. So if you have 100 people fighting, you might actually get 50 people dying, combatant and non-combatant. That's 50 percent. But if you have 3 million people fighting you might get 100,000 dying, which is actually much less, proportionally, than the small-scale society. This is seen by many to suggest that contemporary large societies are less violent than past small scale societies, promoting the idea that before the state, life was nasty, brutish and short," he added.

But when the team applied a scaling law to proportion society, the researchers found that societies today are not necessarily more or less violent than past societies.

The team gathered data on population and war group size from 295 societies and on war group size and conflict-related casualties from 430 historical conflicts, going back to 2500 B.C. They plotted the available data on population size, war group size and conflict casualties.

"We first derived the scaling laws that would explain these trends. Then we gathered the data," Oka said in the report. "And to our very, very pleasant surprise, for both the population and army size, and army size and conflict casualties, we found the scaling laws beautifully explained the distribution."

Using the size of the war group and number of conflict casualties and proportioning them based on the overall population is not a new concept. But the wide dataset the team used enabled them to show the degree of violence across a period of human development that made it easy to compare.

As population size goes up and societies form into states, Oka said, the size of an army or fighters becomes “proportionally smaller, more nimble and more specialized.”

The inferences drawn from the scaled data showed there is more or less no change in the level of violence we exhibit as a species. Even as societies grew and technology developed, we remain just as impulsive and aggressive as our primitive elders.

The study was published in journal Proceedings to National Academy of Sciences of the Unites States of America in November.