About 300,000 years ago, there were at least nine kinds of people on Earth, but now there is only one. Genocide addiction may be an integral, instinctive part of human nature.
Nick Longreach, a senior lecturer in paleontology and evolutionary biology at Bath University, is exploring the unpleasant truth that we were as deadly in the past as we are now.
Nine human species walked the Earth 300,000 years ago. Now only one remains. Neanderthals, Homo neanderthalensis, were stocky hunters adapted to the cold steppes of Europe.
Related Denisovans inhabited Asia, while the more primitive Homo erectus lived in Indonesia, and Homo rhodesiensis lived in Central Africa.
Next to them lived several undersized species with a small brain: Homo naledi in South Africa, Homo luzonensis in the Philippines, Homo floresiensis (“hobbits”) in Indonesia and the mysterious red deer cave people in China.
Given how quickly we discover new species, they are likely to wait even more to be found.
By 10,000 years ago, they all disappeared. The extinction of these other species resembles mass extinction. But no obvious environmental catastrophe – volcanic eruptions, climate change, collision with asteroids – did not occur.
Instead, extinction suggests that it was caused by the spread of a new species that evolved 260,000-350,000 years ago in South Africa: Homo sapiens.
The proliferation of modern humans from Africa has led to the sixth mass extinction, an over 40,000-year-old event ranging from the extinction of ice age mammals to the destruction of tropical forests by modern civilization. But were other people the first victims?
We are an extremely dangerous species. We hunted shaggy mammoths, terrestrial sloths and MOA until their complete disappearance. We destroyed plains and forests for farming, changing more than half of the planet’s land. We have changed the climate of the planet. But we are most dangerous to other human populations because we are competing for resources and land.
History is full of examples of how people fought, ousted and destroyed other groups on their territory, from the destruction of Carthage by Rome to the American conquest of the West and the British colonization of Australia.
Like language or the use of tools, the ability and tendency to genocide may be an integral, instinctive part of human nature. There is no reason to believe that the early Homo sapiens were less territorial, less aggressive, less intolerant – less human.
Optimists portrayed the early hunter-gatherers as peaceful, noble savages and argued that our culture, not our nature, creates violence. But field research, historical records, and archeology all show that the war in primitive cultures was intense, pervasive, and deadly.
Neolithic weapons such as batons, spears, axes and bows, combined with guerrilla tactics such as raids and ambushes, were devastatingly effective. Violence was the leading cause of death among men in these societies, and in wars the level of per capita losses was higher than in the First and Second World Wars.
Old bones and artifacts show that this violence is ancient. A 9,000-year-old Kennewick man from North America has a spear tip stuck in his pelvis. At the 10,000-year-old Nataruk facility in Kenya, at least 27 men, women and children were brutally murdered.
The skeletons of Neanderthals demonstrate the nature of injuries characteristic of hostilities. But modern weapons probably gave homo sapiens a military advantage. The arsenal of early homo sapiens probably included throwing weapons, such as darts and javelin throwers, throwing sticks and batons.
Sophisticated tools and culture would also help us efficiently collect a wider range of animals and plants, feed larger tribes, and give our species a strategic advantage in numbers.
But cave paintings, carvings, and musical instruments allude to something much more dangerous: a sophisticated ability to abstract thinking and communication. The ability to collaborate, plan, develop a strategy, manipulate and deceive, perhaps this was our main weapon.
The incompleteness of the fossil record makes it difficult to verify these ideas. But in Europe, the only place with a relatively complete archaeological record, fossils show that within a few thousand years after our arrival, the Neanderthals disappeared.
Traces of Neanderthal DNA from some Eurasian peoples prove that we did not just replace them after they became extinct. We met and connected.
Elsewhere, DNA speaks of other encounters with archaic people. East Asian, Polynesian and Australian groups have DNA from Denisovans. DNA of another species, possibly Homo erectus, is found in many Asian people. African genomes show traces of DNA from another archaic species. The fact that we crossed with these other species proves that they disappeared only after meeting with us.
But why did our ancestors destroy their relatives, causing mass extinction – or, perhaps more precisely, mass genocide?
The answer lies in population growth. People breed exponentially, like all species. Without any restrictions, we historically doubled our numbers every 25 years. And when people began to hunt together, we no longer had predators.
Without predation controlling our numbers and little family planning, in addition to delayed marriage and infanticide, the population grew to use available resources.
Further growth or food shortages caused by drought, harsh winters or excessive pasture reserves will inevitably lead the tribes to a conflict over food and fodder territory. The war has become a deterrent to population growth, perhaps the most important.
Our elimination of other species was probably not a planned, coordinated attempt, similar to that practiced by civilizations, but a war of attrition. However, the end result was equally final. Raid by raid, ambush by ambush, Valley by valley, modern people destroyed their enemies and seized their lands.
However, the extinction of Neanderthals, at least, took a long time – thousands of years. This was partly due to the fact that the early Homo sapiens did not have the advantages of later conquering civilizations: the large population supported by agriculture, and epidemic diseases such as smallpox, flu, and measles that devastated their opponents.
But while the Neanderthals lost the war to hold out for so long, they had to fight and win many battles against us, suggesting an intelligence level close to our own.
Today we look at the stars and wonder if we are alone in the universe. In fantasy and science fiction, we wonder what it feels like to meet other sentient beings, like us, but not with us. It is very sad to think that once we did this, but now they have disappeared because of this.
Nick Longreach, Senior Lecturer, Department of Paleontology and Evolutionary Biology, University of Bath