In a study published today in the journal Nature, a team of anthropologists describe a prehistoric mass grave whose inhabitants died a violent death, evidence that small-scale warfare was alive and well even among hunter-gatherer communities.Despite what you may have read, there is plenty of evidence for organized violence among hunter-gatherers. Their violence usually doesn't rise to a level we would call warfare because populations are small and dispersed. But in very rich environments that supported dense populations, such as the northwest coast of North America, there were hunter-gatherers (well, mostly fishers) who waged war with fleets of canoes, enslaved whole villages of their enemies, and other things we tend to associate with civilization.
The site, discovered in Nataruk, Kenya, in 2012, housed the remains of 27 people, including 12 intact skeletons. Based on carbon dating of the bones and surrounding sediment, the researchers estimate that the deaths took place somewhere between 9,500 and 10,500 years ago.
Ten of the bodies had signs of injuries that were likely lethal: Five showed evidence of blunt-force head trauma, and five or six (one was ambiguous) had markings consistent with arrow wounds around the head and neck. Several of the skeletons also had fractured hands, knees, and ribs, and some were found in positions suggesting that their arms and legs had been bound.
The researchers also discovered a few arrows at the site made of obsidian, a volcanic rock that wasn’t native to the area, indicating that whoever had attacked had traveled far from home to do so.
Based on our nature, it seems obvious to me that humans evolved in an environment of frequent violence against outsiders. Here is just one more confirmation.