Inter-group violence among early Holocene hunter-gatherers of West Turkana, Kenya
Mirazon Lahr M, Rivera F, Power RK, Mounier A, Copsey B, Crivellaro F, Edung JE, Maillo Fernandez JM, Kiarie C, Lawrence J, Leakey A, Mbua E, Miller H, Muigai A, Mukhongo DM, Van Baelen A, Wood R, Schwenninger J-L, Grün R, Achyuthan H, Wilshaw A & Foley R (2016) Inter-group violence among early Holocene hunter-gatherers of West Turkana, Kenya. Nature 529: 394-398. doi:10.1038/nature16477
Warfare among hunter-gatherers from Nataruk, West Turkana, 10,000 years ago
Marta Mirazón Lahr
10,000 years ago, Turkana was lush and fertile. The IN-AFRICA Project has discovered many sites from this time along the ancient shore of a much larger Lake Turkana, with thousands of animal fossils – elephants, hippopotamuses, rhinos, giraffe, zebras, warthogs, buffaloes, antelopes, gazelles, primates, hyraxes, snakes, turtles, crocodiles and fish, as well as lions, hyaenas and wild dogs. The edge of the lake at that time was an amazing, but also dangerous, place to live. The people of Southwest Turkana were hunters, gatherers, and fishers then- we have found signs of hunting and butchering in animal fossils, as well as hundreds of barbed bone harpoons used for fishing. We also found pottery dating from this time, probably used for keeping water, or fish, or berries, or even perhaps hippotamus fat. Nataruk is one of these sites, a temporary camp where a band of hunter-gatherers went to fish and hunt.
The discoveries at Nataruk
In 2012, Pedro Ebeya, a Turkana fossil hunter working with the IN-AFRICA Project, reported seeing fragments of human bones on the surface at Nataruk. Upon surveying the site, it quickly became apparent that Nataruk was exceptional not only in the number of exposed remains, but also in their close proximity to each other. By the time the excavations were completed, we had found the remains of 27 people – 6 young children, 1 teenager and 20 adults. Twelve of the skeletons – 7 men and 5 women, were found as they had died, unburied until they were covered by the shallow water of the lagoon.
Ten of these 12 skeletons show lesions caused by violence – in the head, neck, ribs, hands, and knees, all the parts of the body most commonly involved in cases of violence. These include 2 cases of projectiles in direct association with the remains, one still embedded on the side of the skull, 2 cases of sharp-force trauma to the neck, 7 cases of blunt and/or sharp-force trauma to the head, 2 cases of blunt-force trauma to the knees and 1 to the ribs, and 2 cases of fractures to the hands, possibly caused while parrying a blow.
The lesions tell us that they were caused by at least 3 types of weapons – projectiles (stoned-tipped as well as sharpened arrows), by a weapon similar to a club, and by another close-proximity weapon, possibly a club or wooden handle with hafted sharp stone blades that caused deep cuts. Two individuals have no lesions in the preserved parts of the skeleton, but the position of their hands suggests they may have been bound, including a young woman who was heavily pregnant at the time.
The skeleton of a young pregnant woman who died at Nataruk, KNM-WT 71255. Image and illustrations by Marta Mirazon Lahr |
We dated the remains and the site through three different methods – radiocarbon, optically stimulated luminescence, and Uranium-series, showing them to be between 10,500 and 9,500 years ago. This makes Nataruk the earliest scientifically dated case of a conflict between two groups of hunter-gatherers.
Nataruk and the prehistory of warfare
Warfare, or inter-group conflict, is today associated with one group of people wanting the territory, resources, or power held by another. Prehistoric hunter-gatherer societies were not sedentary and did not own land or have significant possessions, and their small numbers constrained the development of social hierarchies. Therefore, many scholars have argued that warfare only emerged after sedentism, farming, and more complex political systems arose. However, the findings at Nataruk show that inter-group conflict has a much longer history.
This challenges our views of what are the causes of conflict. It is possible that human prehistoric societies simply responded antagonistically to chance-encounter with another group. This however is not what seems to have happened at Nataruk.
The group who attacked the people at Nataruk was carrying weapons that would not normally be carried while hunting and fishing. The lesions show that clubs of at least two sizes were used, indicating that more than one of the attackers were isolated, of violent trauma in this area from this period in time – one discovered in the 1970s ~20 km north of Nataruk, and two discovered by our project at a nearby site. All three involved projectiles, one of the hall-marks of inter-group conflict. Finally, two of the projectiles found embedded in the bones at Nataruk and in 2 of the other 3 cases of violent trauma in Southwest Turkana were made of obsidian, a rare stone in this area, suggesting that the attackers came from a different place. This tells us that such attacks happened multiple times in at least 3 different locations, all relatively nearby each other, and were part of the life of the hunter-gatherer communities at the time.
So why were the people of Nataruk attacked? We have to conclude that they had valuable resources that were worth fighting for – water, game and its meat, fish, nuts, or indeed women and children. This suggests that two of the conditions associated with warfare among settled societies – territory and resources – were probably the same for these hunter-gatherers, and that we have underestimated their role in prehistory.
Evolution is about survival, and our species is no different from others in this respect. When resources are not enough, competing is part of surviving, and when groups thrive and expand over the territory of others, it can lead to conflict. The key to prehistoric conflict was probably population density – very low numbers may have inhibited warfare, while inter-group conflict may have been common in periods of food abundance and increased population density. These conditions have been a recurrent part of our evolutionary history, making Nataruk extraordinary not because warfare was rare, but because it is rarely preserved in the archaeology of nomadic peoples.
The injuries suffered by the people of Nataruk – men and women, pregnant or not, young and old, shock for their mercilessness. Nevertheless, the devastating event they silently tell of does not make war and violence inevitable outcomes of our nature, but show that, under certain conditions, fighting for what others have may be the only way to survive. Unexpectedly, perhaps, those conditions arose when resources were plentiful.
What we see at the prehistoric site of Nataruk is no different from the wars throughout much of our history, and that sadly continue to shape our lives. But we should not forget that humans, uniquely in the animal world, are also capable of extraordinary acts of altruism, compassion and caring – clearly both are part of our nature.