"Long before it's in the papers"
January 27, 2015


Honor and revenge: how tribal warfare sheds light on modern violence

March 30, 2005
Courtesy of the University of Missou12
and World Science staff

Un­der­stand­ing trib­al wars in the Am­a­zon jun­gle sheds light on the in­stincts that drive mod­ern wars—and on how cul­ture in­flu­ences the pro­cess, re­search sug­gests.

In a new study pub­lished in the re­search jour­nal Ev­o­lu­tion & Hu­man Be­hav­ior, an­thro­po­l­o­gists say vi­o­lent con­flict ac­counted for 30 per­cent of all deaths among Am­a­zon tribes be­fore their con­tact with Eu­ro­peans.

“The same rea­sons – re­venge, hon­or, ter­ri­to­ry and jeal­ousy over wom­en – that fu­eled deadly con­flicts in the Am­a­zon con­tin­ue to drive vi­o­lence in to­day’s world,” said Uni­vers­ity of Mis­souri an­thro­po­l­o­gist Rob­ert Walk­er, the lead au­thor. “Hu­mans’ ev­o­lu­tion­ary his­to­ry of vi­o­lent con­flict among ri­val groups goes back to our pri­mate [ape] an­ces­tors. 

Na­tive Brazil­ians from the tribes As­surini, Tapi­rajé, Ka­iapó, Kapi­rapé, Rik­bak­tsa and Bororo-Boe. (Cred­it: Licínio Mi­ran­da, Wiki­me­dia Com­mons)

“It takes a great deal of so­cial train­ing and in­sti­tu­tion­al con­trol to re­sist our in­stincts and solve dis­putes with words in­stead of weapons,” he added. “For­tu­nately, peo­ple have de­vel­oped ways to chan­nel those in­stincts away from ac­tu­al deadly con­flict. For ex­am­ple, sports and vi­deogames of­ten in­volve the same im­pulses to de­feat a ri­val group.”

Walk­er ex­am­ined records of 1,145 vi­o­lent deaths in 44 so­ci­eties in South Amer­i­ca’s Am­a­zon Riv­er ba­sin by re­view­ing 11 pre­vi­ous an­thro­po­log­i­cal stud­ies. He an­a­lyzed the deaths on a case-by-case ba­sis to de­ter­mine what cul­tur­al fac­tors in­flu­enced the body counts. 

In­ter­nal raids among tribes with si­m­i­lar lan­guages and cul­tures were found to be more fre­quent, but with few­er fa­tal­i­ties, when com­pared to the less fre­quent, but dead­li­er, ex­ter­nal raids on tribes of dif­fer­ent lan­guage groups.

“Lan­guage and oth­er cul­tur­al dif­fer­ences play a role in the ‘clash of civ­il­iz­a­tions’ that re­sulted in re­cent vi­o­lence, such as the deadly at­tack on the U.S. em­bas­sy in Lib­ya and the con­tin­u­ing war in Afghanistan,” said Walk­er. “Work­ing to de­vel­op a shared sense of hu­man­ity for all the Earth’s peo­ple could help re­duce ma­jor episodes of vi­o­lence by en­cour­ag­ing peo­ple to view each oth­er as one un­ified group work­ing to­wards com­mon glob­al goals.”

Raids al­so some­times in­volved kid­nap­ping wom­en, added Walk­er, who co-au­thored the work with Drew Bai­ley, a re­cent doc­tor­al grad­u­ate in psy­cho­log­i­cal sci­ence at the uni­vers­ity. A si­m­i­lar num­ber of wom­en were found to have been kid­napped on av­er­age in both in­ter­nal and ex­ter­nal raids. 

Anoth­er as­pect of Am­a­zonian war­fare was treach­ery, such as in­vit­ing a ri­val group to a feast and then slaugh­ter­ing them af­ter they got drunk, Walk­er said. Some of these at­tacks brought about enor­mous har­vests of death.

“Re­venge was nec­es­sary in his­tor­i­cal intertrib­al war­fare, just as in mod­ern gang con­flicts, be­cause show­ing weak­ness would re­sult in fur­ther at­tacks,” Walk­er said. “That cy­cle of re­venge could re­sult in tribes wip­ing each oth­er out. Af­ter Eu­ro­pe­an con­tact, the dy­nam­ics of Am­a­zonian trib­al life changed dra­mat­ic­ally. Al­though the spread of Chris­tian­ity and im­po­si­tion of na­t­ional le­gal struc­tures re­sulted in a great loss of cul­tur­al ident­ity, it al­so re­duced deadly raids. To­day, such vi­o­lence is rare. Dis­ease and con­flict with ille­gal log­gers and min­ers have be­come the more com­mon causes of death.”

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Understanding tribal wars in the Amazon jungle sheds light on the instincts that drive modern wars—and on how culture influences the process, research suggests. In a new study published in the research journal Evolution & Human Behavior, anthropologists say violent conflict accounted for 30 percent of all deaths before contact with Europeans among Amazon tribes. “The same reasons – revenge, honor, territory and jealousy over women – that fueled deadly conflicts in the Amazon continue to drive violence in today’s world,” said University of Missouri anthropologist Robert Walker, the lead author. “Humans’ evolutionary history of violent conflict among rival groups goes back to our primate ancestors. “It takes a great deal of social training and institutional control to resist our instincts and solve disputes with words instead of weapons,” he added. “Fortunately, people have developed ways to channel those instincts away from actual deadly conflict. For example, sports and video games often involve the same impulses to defeat a rival group.” Walker examined records of 1,145 violent deaths in 44 societies in South America’s Amazon River basin by reviewing 11 previous anthropological studies. He analyzed the deaths on a case-by-case basis to determine what cultural factors influenced the body counts. Internal raids among tribes with similar languages and cultures were found to be more frequent, but with fewer fatalities, when compared to the less frequent, but deadlier, external raids on tribes of different language groups. “Language and other cultural differences play a role in the ‘clash of civilizations’ that resulted in recent violence, such as the deadly attack on the U.S. embassy in Libya and the continuing war in Afghanistan,” said Walker. “Working to develop a shared sense of humanity for all the Earth’s people could help reduce major episodes of violence by encouraging people to view each other as one unified group working towards common global goals.” Raids also sometimes involved kidnapping women, added Walker, who co-authored the work with Drew Bailey, a recent doctoral graduate in psychological science at the university. A similar number of women were found to have been kidnapped on average in both internal and external raids. Another aspect of Amazonian warfare was treachery, such as inviting a rival group to a feast and then slaughtering them after they got drunk, Walker said. Some of these attacks brought about enormous harvests of death. “Revenge was necessary in historical intertribal warfare, just as in modern gang conflicts, because showing weakness would result in further attacks,” Walker said. “That cycle of revenge could result in tribes eradicating each other. After European contact, the dynamics of Amazonian tribal life changed dramatically. Although the spread of Christianity and imposition of national legal structures resulted in a great loss of cultural identity, it also reduced deadly raids. Today, such violence is rare. Disease and conflict with illegal loggers and miners have become the more common causes of death.”