The last few years have seen an alarming increase in claims that tribal peoples have been shown to be more violent than we are. This is supposed to prove that our ancestors were also brutal savages.

Such a message has profound implications for how we view human nature - whether or not we see war as innate to the human condition and so, by extension, broadly unavoidable.

It also underpins how industrialized society treats those it sees as 'backward'. In reality though it's nothing more than an old colonialist belief, masquerading once again as 'science'. There's no evidence to support it.

The American anthropologist, Napoleon Chagnon, is invariably cited in support of this brutal savage myth. He studied the Yanomami Indians of Amazonia from the 1960s onwards (he spells the tribe 'Yanomamö') and you'd be hard pressed to find a book or article on tribal violence which doesn't refer to his work.

Popular writers such as Steven Pinker and Jared Diamond frequently make much of Chagnon's thesis, so it's worth giving a thumbnail sketch of why in reality it proves little about the Yanomami, and nothing about human evolution.

Rejected by anthropologists, alive and well in popular culture

First, it's important to dispatch a red herring from the murky cauldron being cooked up by the brutal savage promoters: They often point to Darkness in El Dorado, a book by Patrick Tierney, which attacked Chagnon's work, but went too far.

Tierney raised the possibility that one of Chagnon's colleagues may have deliberately introduced a deadly measles epidemic to the Indians. That simply wasn't true: In fact, the epidemic was inadvertently started by American missionaries.

That Tierney was wrong on this single point is now used to claim that all his and other writers' criticisms of Chagnon have been discredited. They haven't. In any case, were a single error deemed to negate a whole thesis, then pretty much all science, as well as journalism, the law and a lot else, falls apart.

Anyway, let's set Tierney aside. For decades, Napoleon Chagnon's findings have been rejected by almost all of the many other anthropologists who have worked with the Yanomami, and in most countries his work simply isn't taught. He had rather faded from anthropology in the United States too, until his recent resurgence as the darling of establishment attitudes.

According to Chagnon, brutality is a key driver of human evolution. How did he come upon such a disturbing 'discovery'? Basically, he counted how many Yanomami men boasted that they were unokai and he told us this means they've killed people. He then crunched the numbers to show that unokai are similarly successful in love as they are in war, and that by fathering more children than non-killers, they ensure the next generation is as murderous as they are.

Accidental misunderstanding or deliberate falsification?

As with any sweeping conclusion in human sciences, there are numerous known unknowns. For example, did Yanomami raiding in the 1960s increase through growing pressure from settler or missionary incursions? (After all, Chagnon used the extremist New Tribes Mission to get into the Yanomami.)

Did the influx of outside trade goods, including guns, play a role? Such impacts are difficult to analyze, though some believe they were clearly significant.

But the most significant fact, the extraordinary single error that, in this case, does destroy Chagnon's thesis in one swoop, is something Chagnon doesn't tell us - unokai does not just mean 'killer'. It's also the status claimed by everyone who's ever shot an arrow into a dead body during an inter-village raid (most raids stop after one killing).

It describes many other individuals as well, including men who've killed an animal thought to be a kind of shamanic embodiment of a human, as well as stay-at-homes who try and cast lethal spells. It even includes those who've participated in a ritual during their future wife's puberty (she also becomes unokai).

In other words, many unokai haven't killed anyone. With this simple fact, every one of Chagnon's conclusions about 'killers' falls apart.

But supposing he was right after all, what would his figures show? What percentage of the population are we talking about? Here the brew gets fishier: Chagnon plays fast and loose with his own data. His autobiography, Noble Savages, says that "killers" number "approximately 45 percent of all the living adult males."

Yet even according to his own (shaky) data, that is simply not true: Chagnon's own figures do not show that 45% of men are unokai. He has grossly inflated his percentage by ignoring everyone younger than 25, an age group with far fewer claiming unokai status. Were they included, his percentage would plummet.

Chagnon has been asked about this manipulation for years. When he bothers to reply, he claims he'll publish new supporting data. We're still waiting.

Don't let the awkward facts get in the way of a great story!

So there you have it: That's the poster boy of the 'scientific proof' behind the myth of the brutal savage. The fact that Chagnon's thesis has been repeatedly demolished in scholarly publications for decades is simply ignored by those who want him to be right.

For them to dismiss the many Chagnon critics, to pretend that science is on their side, and to chorus sneeringly 'noble savages' whenever Chagnon is criticized, is just facile propaganda.

By the way, if you want to know how many unokai (supposed 'killers') Chagnon managed to winkle out during a quarter century of fieldwork with one of Amazonia's largest tribes - numbering several thousand - the answer is just 137 men. They could all comfortably fit into a single car on the New York subway. How many of those were actually killers? We'll never know.

That's the size of the sample group supposedly proving that tribal peoples live in a state of chronic warfare and, by throwing in more red herrings, that our ancestors did so too. The latter assertion is widely promulgated.

It goes like this: The Yanomami are a small-scale tribal (non-state) hunting society, our ancestors were the same, so the Yanomami can teach us about our ancestors because they live in a similar way. And yet the theory fails on several points: For example, no one knows the degree to which our distant ancestors scavenged for meat, rather than actively hunted it. That's quite a different approach to life, and the Yanomami wouldn't dream of doing it.

In any case, a moment's informed reflection tells you that no one who inhabited the ice age plains of Eurasia, for example, lived remotely like the tropical rainforest Yanomami of Chagnon's 1960s.

The prosaic truth: different peoples are different

The real story is more obvious, prosaic and simpler than the Chagnon-created 'fierce people' and their supposed 'chronic' warfare. The truth is that there are some tribal peoples who have a belligerent reputation, others known for avoiding violence as much as possible, and lots in between.

That's nothing to do with any grasping at mythic noble savages, it's what anthropologists have actually found.

Despite the growing mythology, the archeological record reveals very little evidence of past violence either (until the growth of big settlements, starting around 10,000 years ago). Researchers Jonathan Haas and Matthew Piscitelli studied descriptions of 2,930 earlier skeletons from 900 different sites worldwide.

Apart from a single massacre site of two dozen people in the Sudan, they found "but a tiny number of cases of violence in skeletal remains", and noted how just four sites in Europe "are mentioned over and over by multiple authors" striving to demonstrate the opposite of what the evidence actually reveals. The archeological record before 10,000 years ago, they conclude, in fact "shows that warfare was the rare exception."

Much of the other 'proof' for the brutal savage advanced by Steven Pinker, Jared Diamond, and other champions of Chagnon, is rife with the selection and manipulation of facts to fit a desired conclusion.

To call this 'science' is both laughable and dangerous. These men are desperate to persuade us that they've got 'proof' for their opinions, which isn't surprising as they're nothing more - opinions based on a narrow and essentially self-serving political point of view. They have proved nothing, except to those who want to believe them.

The real danger is the 'brutal savage' myth itself

Does it matter? Yes, very much. How we think of tribal peoples dictates how we treat them. Proponents of Chagnon seek to reestablish the myth of the brutal savage which once underpinned colonialism and its land theft.

It's an essentially racist fiction which belongs in the 19th century and, like a flat Earth, should have been discarded generations ago. It's the myth at the heart of the destruction of tribal peoples and it must be challenged.

And it's not just deadly for tribal peoples: it's dangerous for all of us. False claims that killing is a proven key factor in our evolution are used to justify, even ennoble, the savagery inherent in today's world.

The brutal savage may be a largely invented creature among tribal peoples, but he is certainly dangerously and visibly real much closer to home.

Stephen Corry has worked with Survival International, the global movement for tribal peoples' rights, since 1972.

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This article was originally published on CounterPunch.