Yanomami Ax Fight

The Yanomami Ax Fight, an ethnographic film by Timothy Asch and Napoleon Chagnon, is a classic in anthropology and beyond. I first saw it as an undergraduate in an English class on travel writing. I have shown it in my classes to illustrate how what we may initially see as chaos or senseless can with another look be seen as part of a logical pattern, as an initial answer to What is Anthropology?

Much has been said about the Yanomami and The Ax Fight, but here I want to concentrate on just one point: steel axes. The Yanomami used iron and steel long before anyone ever filmed them for classroom consumption. As Brian Ferguson writes in Yanomami Warfare: A Political History, “the Yanomami have long depended on iron and steel tools. All ethnographically described Yanomami had begun using metal tools long before any anthropologist arrived” (1995:23).

As noted in Myths of the Spanish Conquest, steel arrived with the Spaniards, but steel tools were quickly seized upon and traded far in advance of any European contact or conquest. In 1491: New Revelations of the Americas Before Columbus, Charles Mann argues that the very form of slash-and-burn cultivation practiced by the Yanomami and often portrayed as so traditional, “was a product of European axes” (2006:341).

Similarly in Papua New Guinea, including for the famously and only-recently-contacted New Guinea highlands, steel axes had been in use for many years before anthropologists arrived. From Aaron Podolefsky’s classic article Contemporary Warfare in the New Guinea Highlands: “Enter the ubiquitous steel axe, exit the stone axe. No one in Mul today would use a stone axe. Indeed it was difficult to find someone who recalled how to attach the stone to a handle” (345).

Keep in mind that when Podolefsky says today, he is describing his fieldwork in the early 1970s!

It is very strange that Jared Diamond, who sold the world on the importance of steel as a formidable weapon of conquest, has so little to say about steel axes in The World Until Yesterday. Jared Diamond mentions people in the New Guinea highlands received “a few steel axes, which were prized.” But this doesn’t sound at all like what Podolefsky describes as steel axes being ubiquitous by the early 1970s, so much so that no one knew how to make a stone axe anymore. Jared Diamond also mentions–with regard to the Solomon Islands in the 19th century–that “steel axes can behead many humans without losing their sharp edge.” But those are the only two mentions–otherwise steel axes are unnoticed, even among the Yanomami.

Steel axes are not the cause of violence–rather, they indicate centuries of trade and interconnection, of the interactions between state and non-state societies since well before Europeans arrived and outrunning European contact. It is in this context that we need to investigate the empirical data about violence in non-state societies.

The Yanomami, Counting Violence, & Shaky Science

Following on an overview of what accounts for the rise of European polities 800-1400AD and then a re-appraisal of the colonial enterprise in the Americas, this post means to draw out the major theme running through the earlier work: that anthropological studies are inevitably studies of interconnection. People have never been isolated, but in constant connection, from before the time of European expansion. Moreover, the effects of European expansion outran direct contact with Europeans, as items like steel axes and a host of agricultural products were traded around the world, often without any direct European involvement whatsoever (Charles Mann’s 1493: Uncovering the New World Columbus Created has a host of examples, in many cases based on previous anthropological and historical work that paid attention to global flows). We need to put to rest the idea of Ruth Benedict in 1934–that primitive peoples are a kind of scientific laboratory, each an independent cultural whole.

At a time when Angry Papuan leaders demand Jared Diamond apologizes, this task acquires additional urgency. Prominent claimants to the science mantle close ranks with Jared Diamond. Steven Pinker tweets: “Noble savage myth strikes again–Jared Diamond has data on his side; Survival International confuses human rights with factual claims.” Skeptic Michael Shermer raises the hyperbole: “Another example of the Left’s War on Science: Survival International attacks Jared Diamond (whose data is solid).” Prominent economist Tyler Cowen: “Mood affiliation aside, the facts are on Diamond’s side.”

Science blogger Razib Khan takes a strangely different turn. After remarking that Jared Diamond has been “trading in glib and gloss for years,” Khan revs up his favorite diatribe apparatus against cultural anthropology. Khan concludes that “Jared Diamond may be wrong on facts, but he has the right enemies.” Hey, no use bothering with boring facts when terrific Twitter sensationalism awaits.

Real scientists know better. Jared Diamond has a lot of anecdotes, but very little empirical evidence. The few numbers he does use are suspect, and in any case doing math on numbers does not make it science. Before numbers can count as evidence, as empirical data, as facts, as science, it is crucial to understand the context of those numbers. Numbers usefully summarize what we count as important. Numbers offer glimpses into relationships and processes. But we should not confuse the manipulation of numbers with an understanding of those relationships and processes.

We do need to review some facts. Looking at the empirical evidence reveals a very different story. The story matches what Brian Ferguson wrote about the Yanomami, with ideas developed over 20 years ago:

Although some Yanomami really have been engaged in intensive warfare and other kinds of bloody conflict, this violence is not an expression of Yanomami culture itself. It is, rather, a product of specific historical situations: The Yanomami make war not because Western culture is absent, but because it is present, and present in certain specific forms. All Yanomami warfare that we know about occurs within what Neil Whitehead and I call a “tribal zone,” an extensive area beyond state administrative control, inhabited by nonstate people who must react to the far-flung effects of the state presence. (1995:6)

In other words, the whole idea that we are able to compare state and non-state societies based on ethnographic data collected in the past two centuries is unsustainable. These are all people who are reacting to state presence in various ways, and might just as well be conceptualized as being on the poor margins of state societies as being independent non-state units.

Before launching this investigation of interconnection, I do need to clarify a few points:

I love numbers. I love counting. I love math. Numbers, counting, and math are especially useful to counter and debunk stories we like to tell about ourselves and other societies.

This is not about personal quirks or fieldwork ethics. The idea that steel axes were ever introduced by anthropologists is not supported. The point is that the steel axes were there long before the anthropologists.

I am in no way making a counter-claim of peace, harmony, and gentleness. Countering the claim that others live in a state of constant warfare or endemic violence is not to idealize or prop up equally invalid constructions.

I am in no way saying that steel axes cause violence. It is simply to say that the influence of steel axes and other trade goods, as well as contact with other peoples and with both European and non-European states, must be considered before we decide that a certain type of people are inevitably violent or warlike.

Investigating Jared Diamond’s Empirical Evidence

The Yanomami. Brian Ferguson already did a complete empirical revision on the Yanomami evidence 20 years ago. After that work, no reputable scholar should be uncritically citing Napoleon Chagnon for empirical evidence. That this even must be done over again is a farce. Jared Diamond cites only Napoleon Chagnon on the Yanomami. He does not mention Ferguson in his book, nor do we ever hear that there may have been a debate about Yanomami warfare. Somewhat ironically, Ferguson and others cleared this up in the scientific journals years ago, but Jared Diamond gets the scientist label without paying attention to science. [Update: I wrote about Jared Diamond’s uncritical use of Chagnon as a farce before Chagnon’s Noble Savages was published. Click Napoleon Chagnon for more and see also The Times, it is Outragin’ by Jonathan Marks.]

As Charles C. Mann notes in a February 2013 review of Chagnon, Fierce Controversies:

Prior to 1492, these researchers say, this portion of central Amazonia was a prosperous, cosmopolitan, multiethnic network of big villages, fed by fish from the great river and reliant upon a multitude of forest products. When that network was thrown into turmoil by the arrival of European slavers and European diseases, the Yanomamö and many other groups fled into the hinterlands, where they now reside. If this is correct, these people are not “pure” or “pristine”; they are dispossessed. And their existence in small bands is reflective not of humankind’s ancient past but of a shattered society that has preserved its liberty by retreat. It would be risky to base conclusions about the evolution of society on the study of posses of refugees, perhaps especially those who have survived both a holocaust and a diaspora.

The Nuer. Jared Diamond uses E.E. Evans-Pritchard’s classic ethnography on the Nuer to highlight their “prevalence of formalized violence.” However, Evans-Pritchard studied the Nuer because the British colonial government was trying to figure out why they were being so rebellious to colonial rule and how they were organizing their rebellion. As Evans-Pritchard explains, “in 1920 large-scale military operations, including bombing and machine-gunning of camps, were conducted against the Eastern Jikany and caused much loss of life and destruction of property. There were further patrols from time to time but the Nuer remained unsubdued” (The Nuer 1940:135). I should not need to say that a period of widespread resistance to colonial rule, answered with brutal massacres by the colonial state, may not exactly be the most reliable time to objectively tally instances of violence in a “non-state society.”

The Siriono. I have already objected to Jared Diamond’s use of the Siriono as described by anthropologist Alan Holmberg. David Brooks then splayed the Siriono into The New York Times. The first chapter of Mann’s 1491 concerned “Holmberg’s Mistake”–the problem of drawing conclusions about people who were basically a persecuted fragment, a shattered remnant of a former society (see above for Mann’s similar comments with regard to the Yanomami).

Even Holmberg admits in his ethnography that “The Siriono are an anomaly in eastern Bolivia. Widely scattered in isolated pockets of forest land, with a culture strikingly backward in contrast to that of their neighbors, they are probably a remnant of an ancient population that was exterminated, absorbed, or engulfed by more civilized invaders” (Nomads of the Long Bow 1950:8, and I thank the Amazon reviewer Ron Cochran for the reference). No wonder then that according to Jared Diamond “for the Siriono Indians of Bolivia, the overwhelming preoccupation is with food, such that two of the commonest Siriono expressions are ‘My stomach is empty’ and ‘Give me some food.'” Certainly such statements are a testament to something, but they hardly constitute evidence about life in a non-state society.

The !Kung. For the !Kung, Jared Diamond uses Richard Lee’s numbers to calculate 22 homicides from 1920-1969. Diamond then notes that “referred to that base population, the homicide rate for the !Kung works out to 29 homicides per 100,000 person-years, which is triple the homicide rate for the United States and 10 to 30 times the rates for Canada, Britain, France, and Germany.” Diamond then says that state intervention reduced the homicide rate.

Three points: First, Jared Diamond makes a strange comparison to contemporary homicide rates in the industrialized world. If we instead look at intentional homicide rates around the world, the !Kung numbers are roughly equivalent to the country of South Africa today–in other words, there seems to be a broader regional issue. The homicide rates were not worse for the !Kung, and may have even been reduced in comparison to other African locales at the time. Second, grabbing a local homicide number can be tricky–Washington, D.C. had an intentional homicide rate in the low 40s in the early 2000s, which has since come down to mid-20s. I would hope no one suggest Washington D.C. is a non-state society, but Diamond would come close to making such a claim: “Urban gangs in large cities don’t call the police to settle their disagreements but rely on traditional methods of negotiation, compensation, intimidation, and war.”

Third, and most importantly, Richard Lee and Jared Diamond’s choice of time period is instructive. Robert J. Gordon has been for years trying to bring to wider attention The “Forgotten” Bushman Genocides of Namibia. Gordon “examines the Bushman genocide of 1912–1915 which, despite overwhelming evidence of its having occurred, has been largely ignored by both scholars and the local population” (2009:29). If Gordon is correct–and he is one of the only people delving into the German archives for evidence–then the indigenous populations were decimated, with both state and para-state involvement, during the years just before the 22 homicides calculated from 1920-1969. I’ve always wondered if that was one forgotten factor in why Richard Lee got that famous quote about so many mongongo nuts–perhaps because the population of people had been so decimated 50 years earlier (see Agriculture as “Worst Mistake in the History of the Human Race”?).

In any case, and as Robert Gordon and Stuart Sholto-Douglas argue in The Bushman Myth: The Making of a Namibian Underclass, by 1920-1969 these populations were hardly detached from wider society. The !Kung may have been more like the Siriono–a persecuted remnant of a former society–than we have hitherto realized.

Papua New Guinea. Jared Diamond here makes the case that a strong state government decreases violence. Following directly from the !Kung material:

This course of events illustrates the role of control by a strong state government in reducing violence. That same role also becomes obvious from central facts of the colonial and post-colonial history of New Guinea in the last 50 years: namely, the steep decrease in violence following establishment of Australian and Indonesian control of remote areas of eastern and western New Guinea respectively, previously without state government; the continued low level of violence in Indonesian New Guinea under maintained rigorous government control there; and the eventual resurgence of violence in Papua New Guinea after Australian colonial government gradually yielded to less rigorous independent government.

Here again, three points. First, as noted above, Diamond seriously underplays the influence of trade and pre-contact transformation. Even before the steel axes, the New Guinea highlanders had incorporated sweet potato horticulture into their diet. As Stephen Corry notes, while there is still debate about where the sweet potatoes came from, the probable answer is from the Americas in the last few hundred years:

Most New Guineans do little hunting. They live principally from cultivations, as they probably have for millennia. Diamond barely slips in the fact that their main foodstuff, sweet potato, was probably imported from the Americas, perhaps a few hundred or a thousand years ago. No one agrees on how this came about, but it is just one demonstration that “globalization” and change have impacted on Diamond’s “traditional” peoples for just as long as on everyone else. (Savaging Primitives: Why Jared Diamond’s ‘The World Until Yesterday’ Is Completely Wrong)

The incorporation of the sweet potato–just like other food crops from the Americas in other parts of the world–most probably led to denser populations in the highlands than had been previously supported. Add steel axes from trade–which by the time of fieldwork in the 1970s had become ubiquitous–and the conditions were surely ripe for an escalation of intertribal conflict.

Anyone interested in the dramatic global interconnections of Papua New Guinea should watch the truly classic ethnographic film, again from the early 1970s, Ongka’s Big Moka: The Kawelka of Papua New Guinea. Ongka’s Big Moka can certainly be used to illustrate gift exchange and traditional life–but it is also instructive to see the appropriation of all kinds of elements–the “Do It In the Road” T-shirt, dentures, money counted in pidgin English, motorbikes, bank accounts for cash-crop coffee growing–all of which seem to not be destroying the traditional exchanges but intensifying them. That was the situation in the New Guinea highlands in the 1970s, and yet Jared Diamond announces on The Colbert Report that they might not know what to do with an electric can opener, that they might try “sticking it through their nose or over their ears.”

Second, Aaron Podolefsky and other anthropologists explicitly sought to explain this somewhat puzzling resurgence in tribal violence in the 1960s and 1970s. Here again, Robert Gordon provided evidence that this could not simply be explained by a “less rigorous” government. Gordon pointed out the paradox that in many of the conflicted areas, police patrols had actually expanded and the jail penalties enhanced, but with no deterrent effect. Podolefsky’s article emphasizes the importance of trade–since highlanders no longer had to go far afield to obtain valued goods, there had been a decrease in intertribal marriage. This decrease in intertribal marriage led to situations in which there were fewer relatives to argue for peaceful relations (we might also recall the role of affines in Ongka’s Big Moka for reducing the intertribal conflict). In other words, Podolefsky argues that it is in fact the decline or abandonment of traditional methods of dispute resolution which led to this resurgence.

Finally, those ethnographers who are most intimately familiar with the violence and warfare in Papua New Guinea–and who do not in any way dismiss it–nevertheless have suggested that state societies may have something to learn:



Acephalous societies may have some advantages rather than disadvantages vis à vis centralized ones in the settlement of disputes including the handling of violence. The projection of disputes in terms of sorcery and witchcraft can be considered in this context. Our observations here turn ideas of the evolution of society upside down: “primitive” societies, rather than being forms to be transcended, may themselves provide valuable models for contemporary postmodern society on how to reintroduce community-based elements into dispute resolution, and on the mediation and transformation of violence into positive forms of exchange. (Stewart and Strathern, Violence: Theory and Ethnography 2003:153)

The Aché. Jared Diamond also brings up the Aché of Paraguay. Here, I’m just going to go with Wikipedia:

The Aché suffered repeated abuses by rural Paraguayan colonists, ranchers, and big landowners from the conquest period to the 20th century. In the 20th century the Northern Aché began as the only inhabitants of nearly 20,000 square kilometers, and ended up confined on two reservations totaling little more than 50 square kilometers of titled land. In recent times they have been massacred, enslaved, and gathered on to reservations where no adequate medical treatment was provided. This process was specifically carried out to pacify them and remove them from their ancestral homeland so that absentee investors (mainly Brazilian) could move in and develop the lands that once belonged only to the Aché. Large multinational business groups (e.g. Industria Paraguaya) obtained title rights to already occupied lands and then sold them sight unseen to investors who purchased lands where Aché bands had roamed for thousands of years, and were still present. The fact that Aché inhabitants were present and living in the forests of Canindeyu and Alto Paraná on the very lands being titled in Hernandarias, Coronel Oveido, and other government centers seems to have bothered nobody.

The Inuit. Jared Diamond uses the Inuit example more in passing, so I originally did not include it in my review–this responds to a comment below. For the Inuit, Diamond’s claim is that the “visits of traders to the Inuit also had the effect of suppressing Inuit war, even though neither the traders with the Inuit nor those with the !Kung purposely suppressed war. Instead, the Inuit themselves abandoned war in their own self-interest in order to have more opportunities to profit from trade, and the !Kung may have done the same.” In other words, Jared Diamond uses this as an example of how European contact, in the long term, suppresses violence and war, and that for the Inuit they do it in order to profit from trade. Such an account is typical of Diamond’s rather narrow definition of European contact. It is instead far more likely that the fur trade–along with weapons and other technologies–arrived far in advance of direct European contact. Undoubtedly Inuit warfare pre-existed European contact, but became mixed up with introducing alcohol and guns for fur–the subsequent observed pacification could very well have been the aftermath of local competition for access to resources. Again, this is not to claim a peaceful pre-Contact Inuit, but to question the idea that European trade was what suppressed Inuit war.

There is one other comment about almost all of the cases Jared Diamond uses: much of the evidence is based not just on the unproblematic acceptance of these texts, but on the stories people told about the old days of raiding and warfare. And here we should remember that war stories are war stories–like fishing stories and hunting stories, the talk of past exploits sometimes needs to be taken with a few grains of salt.

I had been attempting to not support the Jared Diamond juggernaut by purchasing The World Until Yesterday, but for the sake of science I’ve plunged ahead. After reviewing the empirical data, I’m even more surprised than I expected at how Diamond treats the ethnographic record. I’m even more amazed I have not yet heard mention of this from anthropologists who have reviewed the book–see Anthropology on Jared Diamond – The World Until Yesterday. Are we really so far from empirical evaluation that these reviews were conducted on whether or not we support Jared Diamond’s philosophy, his politics, his methods, his field experience, or his writing style? Where are the anthropologists who have taken Jared Diamond to task for his absurd absorption of the Yanomami, the Nuer, the Siriono, the Aché, the !Kung, and in Papua New Guinea? Even Razib Khan says “I want to be clear that I think Jared Diamond is wrong on a lot of details, and many cultural anthropologists are rightly calling him out on that.” But who are the cultural anthropologists calling Diamond out on the empirical and the ethnographic record? Please let me know!

Lest I be misunderstood, I have no desire to dismiss classic ethnographies. Indeed, I urge that we read, teach, and learn from them. But we need to be clear about what these texts can and cannot provide. We also need to place ethnography in the context of critical assessment. Not a critique of writing or literary deconstruction, but an investigation of empirical claims in the light of history. Put differently:

While empirical data never speak for themselves, anthropologists cannot speak without data. Even when couched in the most interpretive terms, anthropology requires observation–indeed, often field observation–and relies on empirical data in ways and to degrees that distinguish it as an academic prcatice from both literary and Cultural Studies. That such data is always constituted and such observation is always selective does not mean that the information they convey should not pass any test for empirical accuracy. The much welcome awareness that our empirical base is a construction in no way erases the need for such a base. On the contrary, this awareness calls upon us to reinforce the validity of that base by taking more seriously the construction of our object of observation. Ideally this construction also informs that of the object of study in a back and forth movement that starts before fieldwork and continues long after it. But the preliminary conceptualization of the object of study remains the guiding light of empirical observation: “What is it that I need to know in order to know what I want to know?” (Michel-Rolph Trouillot, Global Transformations 2003:128)

What does anthropology’s empirical record reveal about violence and warfare?

It is important to first underscore that we cannot read anthropology’s ethnographic record for evidence of whether or not violence is inherent to human nature, as some have attempted. Fortunately, on this point Jared Diamond is clear and correct: “It is equally fruitless to debate whether humans are intrinsically violent or else intrinsically cooperative. All human societies practise both violence and cooperation; which trait appears to predominate depends on the circumstances.”

It is also important to underscore that human groups have had varying levels of violence, both historically and across both state and non-state societies. Diamond also realizes this point. What I object to is that following these two acknowledgements, Jared Diamond then portrays non-state societies as generally more violent than state societies, and believes that “the long-term effect of European, Tswana, or other outside contact with states or chiefdoms has almost always been to suppress tribal warfare. The short-term effect has variously been either an immediate suppression as well or else an initial flare-up and then suppression.” (Of course, the duration of this “initial flare-up” could be for centuries as Diamond writes a few sentences earlier, that in some cases “warfare had been endemic long before European arrival, but the effects of Europeans caused an exacerbation of warfare for a few decades (New Zealand, Fiji, Solomon Islands) or a few centuries (Great Plains, Central Africa) before it died out.”)

I hope to have shown above that the empirical evidence for those claims is not reliable. Again, this is not to make a counter-proposal of harmonic peace, but to lessen the distance between ideas of the modern us and the non-modern them. If we do give sufficiently wide berth to historical variability and intra-societal variation, I would propose the following as more general observations:



Up until about 12,000 years ago, there is little evidence for much violence or warfare:

If you review the published information on the fossil record of humans and potential human ancestors from about six million years ago through about 12,000 years ago you are provided with, at best, only a few examples of possible death due to the hand of another individual of the same species. . . . Examination of the human fossil record supports the hypothesis that while some violence between individuals undoubtedly happened in the past, warfare is a relatively modern human behavior (12,000 to 10,000 years old). (Fuentes Race, Monogamy, and Other Lies They Told You 2012:130-131) In other words, if by “yesterday” we really do mean 12,000 years ago, pre-agriculture, then these non-state societies are indeed examples of non-violence. This was a point that was first tremendously popularized by none other than Jared Diamond in his breakout 1987 article Worst Mistake in the History of the Human Race. Widely re-printed and still shared today, if anyone is responsible for promoting Noble Savage ideas in the last quarter century, it’s Jared Diamond. Here’s Diamond in 1987: “Forced to choose between limiting population or trying to increase food production, we chose the latter and ended up with starvation, warfare, and tyranny.” Non-state horticultural, agricultural, and herding societies have demonstrated historically variable levels of violence and warfare. Almost all of those non-state horticultural, agricultural, and herding societies, along with almost all of the hunting and gathering peoples in the last several thousand years or so, have lived in interaction with state societies. Some of them have been incorporated into states, others displaced, and those displaced have sometimes displaced other groups. All these groups have been linked by trade. This was happening before European contact, but has certainly intensified in the last 500 years. These state and non-state interactions have sometimes diminished violence and warfare, but have sometimes exacerbated it. If, following Max Weber, we define a state as “the form of human community that (successfully) lays claim to the monopoly of legitimate physical violence within a particular territory,” then indeed–although the argument is a bit circular–it may be that a modern state can reduce violence. However, making that claim as a definition should not impede understanding how the establishment of a monopoly on legitimate physical violence was often itself a violent process, and in many case still depends on high levels of everyday violence, surveillance, incarceration, border patrols.

A Final Thought

In the early 1960s, we came very close to an intercontinental nuclear exchange between the U.S. and the Soviet Union. How precisely close we were is a matter for some debate, but it was a distinct possibility that may have only been averted by personality quirks and fortuitous occurrence, not exactly “the better angels of our nature.” This was something the scholars of the 1960s and 1970s seem to know better than we do today: How dangerously close we once came to ending this whole discussion of the-modern-versus-the-traditional. Or as Richard Lee and Irven DeVore put it in Man the Hunter:

It is still an open question whether man will be able to survive the exceedingly complex and unstable ecological conditions he has created for himself. If he fails in this task, interplanetary archaeologists of the future will classify our planet as one in which a very long and stable period of small-scale hunting and gathering was followed by an apparently instantaneous efflorescence of technology and society leading rapidly to extinction. (1968:3)

Update 2015: For an assessment of steel axes and interconnections see History, explanation, and war among the Yanomami: A response to Chagnon’s Noble Savages by Brian Ferguson in Anthropological Theory (December 2015):

For social relations on the ground, nothing–not even massive deaths from new diseases–has more profound implications. Steel axes and other goods produce not only a technological revolution, transforming indigenous subsistence possibilities, but also a revolution in dependency, in that they only originate with aliens. (386)

Update 2013: See Jonathan Marks, Diamonds and Clubs for an important contribution to understanding the history of political attacks on anthropology. For many of the issues discussed in points #1-4 above–and in the comment stream below–see the new edited volume War, Peace, & Human Nature (2013). For more on the new Napoleon Chagnon memoir, see Napoleon Chagnon – Noble Savages and Epigenetics on The Edge of Human Nature.

To cite: Antrosio, Jason. 2013. “Yanomami Ax Fight: Jared Diamond, Science, Violence, and the Facts.” Living Anthropologically website, https://www.livinganthropologically.com/yanomami-science-violence-empirical-data-facts/. First posted 6 February 2013. Revised 15 September 2017.