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


“Johnny has two daddies” may have been common in Amazon cultures

Nov. 10, 2010
Courtesy of the University of Missouri
and World Science staff

Some mod­ern schools are find­ing it a del­i­cate task to ex­plain to chil­dren that a class­mate has “two mom­mies” or “two dad­dies”—a phe­nom­e­non due mostly to grow­ing ac­cept­ance of gay rela­t­ion­ships and, in some ar­eas, gay mar­riages.

Yet a ver­sion of that con­versa­t­ion may have been quite com­mon in many tra­di­tion­al Am­a­zo­ni­an cul­tures of the past, a study has found. The rea­son for it, though, would have been quite dif­fer­ent: ex­tra­mar­i­tal sex­u­al af­fairs were com­mon, and peo­ple thought that when a wom­an got preg­nant, each of her sex­u­al part­ners was in part the bi­o­log­i­cal fa­ther.

The stu­dy, pub­lished in the re­search jour­nal Pro­ceed­ings of the Na­tional Acad­e­my of Sci­ences, found that up to 70 per­cent of Am­a­zo­ni­an cul­tures stud­ied in the past may have be­lieved in “mul­ti­ple pa­tern­ity” at the time. The study is based on de­tailed an­thro­po­l­o­gists’ de­scrip­tions of so­ci­eties across low­land South Amer­i­ca, which in­cludes Bra­zil and many of the sur­round­ing coun­tries.

“In these cul­tures, if the moth­er had sex­u­al rela­t­ions with mul­ti­ple men, peo­ple be­lieved that each of the men was, in part, the child’s bi­o­log­i­cal fa­ther,” ex­plained an­thro­po­l­o­gist Rob­ert Walk­er of the Uni­vers­ity of Mis­souri, one of the re­search­ers in the stu­dy. “It was so­cially ac­cept­a­ble for chil­dren to have mul­ti­ple fa­thers, and sec­ond­ary fa­thers of­ten con­tri­but­ed to their chil­dren’s up­bring­ing.”

Walk­er said promiscu­ity was nor­mal in many tra­di­tion­al South Amer­i­can so­ci­eties, and that mar­ried cou­ples typ­ic­ally lived with the wife’s fam­i­ly, in­creas­ing wom­en’s sex­u­al free­dom.

“In some Am­a­zo­ni­an cul­tures, it was bad man­ners for a hus­band to be jeal­ous,” Walk­er said. “It was al­so con­sid­ered strange if you did not have mul­ti­ple sex­u­al part­ners. Cousins were of­ten pre­ferred part­ners, so it was es­pe­cially rude to shun their ad­vances.”

Pre­vi­ous re­search had re­vealed “mul­ti­ple pa­tern­ity” be­liefs in some Am­a­zo­ni­an cul­tures, Walk­er said, but an­thro­po­l­o­gists did­n’t real­ize how wide­spread such views were. His team an­a­lyzed de­tailed ethno­gra­phies, or an­thro­po­log­i­cal de­scrip­tions, for 128 so­ci­eties. Mul­ti­ple pa­tern­ity is re­ported to ap­pear in 53 so­ci­eties; sin­gu­lar pa­tern­ity is men­tioned in 23; and the other ethno­gra­phies don’t go into con­cep­tion be­liefs, the sci­en­tists found.

Walk­er’s team pro­poses sev­er­al hy­pothe­ses on the ben­e­fits of mul­ti­ple pa­tern­ity. First, sec­ond­ary fa­thers gave gifts and helped sup­port the child, boost­ing child sur­viv­al rates. Sec­ond, bru­tal war­fare was com­mon in an­cient Ama­zo­nia; un­der mul­ti­ple pa­tern­ity a child who lost a fa­ther could still have a fa­ther fig­ure. In ad­di­tion, wom­en be­lieved in es­sence that mul­ti­ple sex­u­al part­ners pro­vid­ed the ben­e­fit of larg­er gene pools for their chil­dren.

Men al­so gained from the mul­ti­ple pa­tern­ity sys­tem be­cause they were able to for­mal­ize al­liances with oth­er men by shar­ing wives, added Walk­er. He hy­poth­e­sizes that mul­ti­ple pa­tern­ity al­so strength­ened family bonds, as broth­ers of­ten shared wives in some cul­tures.

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Some modern schools are finding it delicate task to explain to children that a classmate has “two mommies” or “two daddies”—a phenomenon due mostly to growing acceptance of gay relationships and, in some areas, gay marriages. Yet a version of that conversation may have been quite common in many traditional Amazonian cultures of the past, a study has found. The reason for it, though, would have been quite different: extramarital sexual affairs were common, and people thought that when a woman got pregnant, each of her sexual partners was in part the biological father. The study, published in the resarch journal Proceedings of the National Academy of Sciences, found that up to 70 percent of Amazonian cultures studied in the past may have believed in “multiple paternity” at the time. The study is based on detailed anthropologists’ descriptions of societies across lowland South America, which includes Brazil and many of the surrounding countries “In these cultures, if the mother had sexual relations with multiple men, people believed that each of the men was, in part, the child’s biological father,” explained anthropologist Robert Walker of the University of Missouri, one of the researchers in the study. “It was socially acceptable for children to have multiple fathers, and secondary fathers often contributed to their children’s upbringing.” Walker said promiscuity was normal in many traditional South American societies, and that married couples typically lived with the wife’s family, increasing women’s sexual freedom. “In some Amazonian cultures, it was bad manners for a husband to be jealous,” Walker said. “It was also considered strange if you did not have multiple sexual partners. Cousins were often preferred partners, so it was especially rude to shun their advances.” Previous research had revealed “multiple paternity” beliefs in some Amazonian cultures, Walker said, but anthropologists didn’t realize how widespread such views were. His team analyzed detailed ethnographies, or anthropological descriptions, for 128 societies. Multiple paternity is reported to appear in 53 societies; singular paternity is mentioned in 23; and the rest of the ethnographies don’t describe conception beliefs, the scientists found. Walker’s team proposes several hypotheses on the benefits of multiple paternity. First, secondary fathers gave gifts and helped support the child, boosting child survival rates. Second, brutal warfare was common in ancient Amazonia; under multiple paternity a child who lost a father could still have a father figure. In addition, women believed in essence that by multiple sexual partners provided the benefit of larger gene pools for their children. Men also gained from the multiple paternity system because they were able to formalize alliances with other men by sharing wives, added Walker. He hypothesizes that multiple paternity also strengthened family bonds, as brothers often shared wives in some cultures.