Arquivo da tag: Sociobiologia

Is human behavior controlled by our genes? Richard Levins reviews ‘The Social Conquest of Earth’ (Climate & Capitalism)

“Failing to take class division into account is not simply a political bias. It also distorts how we look at human evolution as intrinsically bio-social and human biology as socialized biology.”


August 1, 2012

Edward O. Wilson. The Social Conquest of Earth. Liverwright Publishing, New York, 2012

reviewed by Richard Levins

In the 1970s, Edward O. Wilson, Richard Lewontin, Stephen Jay Gould and I were colleagues in Harvard’s new department of Organismic and Evolutionary Biology. In spite of our later divergences, I retain grateful memories of working in the field with Ed, turning over rocks, sharing beer, breaking open twigs, putting out bait (canned tuna fish) to attract the ants we were studying..

We were part of a group that hoped to jointly write and publish articles offering a common view of evolutionary science, but that collaboration was brief, largely because Lewontin and I strongly disagreed with Wilson’s Sociobiology.

Reductionism and Sociobiology

Although Wilson fought hard against the reduction of biology to the study of molecules, his holism stopped there. He came to promote the reduction of social and behavioral science to biology. In his view:

“Our lives are restrained by two laws of biology: all of life’s entities and processes are obedient to the laws of physics and chemistry; and all of life’s entities and processes have arisen through evolution and natural selection.” [Social Conquest, p. 287]

This is true as far as it goes but fails in two important ways.

First, it ignores the reciprocal feedback between levels. The biological creates the ensemble of molecules in the cell; the social alters the spectrum of molecules in the biosphere; biological activity creates the biosphere itself and the conditions for the maintenance of life.

Second, it doesn’t consider how the social level alters the biological: our biology is a socialized biology.

Higher (more inclusive) levels are indeed constrained by the laws at lower levels of organization, but they also have their own laws that emerge from the lower level yet are distinct and that also determine which chemical and physical entities are present in the organisms. In new contexts they operate differently.

Thus for example we, like a few other animals including bears, are omnivores. For some purposes such as comparing digestive systems that’s an adequate label. But we are omnivores of a special kind: we not only acquire food by predation, but we also producefood, turning the inedible into edible, the transitory into stored food. This has had such a profound effect on our lives that it is also legitimate to refer to us as something new, productivores.

The productivore mode of sustenance opens a whole new domain: the mode of production. Human societies have experienced different modes of production and ways to organize reproduction, each with its own dynamics, relations with the rest of nature, division into classes, and processes which restore or change it when it is disturbed.

The division of society into classes changes how natural selection works, who is exposed to what diseases, who eats and who doesn’t eat, who does the dishes, who must do physical work, how long we can expect to live. It is no longer possible to prescribe the direction of natural selection for the whole species.

So failing to take class division into account is not simply a political bias. It also distorts how we look at human evolution as intrinsically bio-social and human biology as socialized biology.

The opposite of the genetic determinism of sociobiology is not “the blank slate” view that claims that our biological natures were irrelevant to behavior and society. The question is, what about our animal heritage was relevant?

We all agree that we are animals; that as animals we need food; that we are terrestrial rather than aquatic animals; that we are mammals and therefore need a lot of food to support our high metabolic rates that maintain body temperature; that for part of our history we lived in trees and acquired characteristics adapted to that habitat, but came down from the trees with a dependence on vision, hands with padded fingers, and so on. We have big brains, with regions that have different major functions such as emotions, color vision, and language.

But beyond these general capacities, there is widespread disagreement about which behaviors or attitudes are expressions of brain structure. The amygdala is a locus of emotion, but does it tell us what to be angry or rejoice about? It is an ancient part of our brains, but has it not evolved in response to what the rest of the brain is doing? There is higher intellectual function in the cortex, but does it tell us what to think about?

Every part of an organism is the environment for the rest of the organism, setting the context for natural selection. In contrast to this fluid viewpoint, phrases such as “hard-wired” have become part of the pop vocabulary, applied promiscuously to all sorts of behaviors.

In a deeper sense, asking if something is heritable is a nonsense question. Heritability is always a comparison: how much of the difference between humans and chimps is heritable? What about the differences between ourselves and Neanderthals? Between nomads and farmers?

Social Conquest of Earth

The Social Conquest of Earth, Ed Wilson’s latest book, continues his interest in the “eusocial” animals – ants, bees and others that live in groups with overlapping generations and a division of labor that includes altruistic behavior. As the title shows. he also continues to use the terminology of conquest and domination, so that social animals “conquer” the earth, their abundance makes them “dominate.”

The problem that Wilson poses in this book is first, why did eusociality arise at all, and second, why is it so rare?

Wilson is at his best when discussing the more remote past, the origins of social behavior 220 million years ago for termites, 150 million years for ants, 70-80 million years for humble bees and honey bees.

But as he gets closer to humanity the reductionist biases that informed Sociobiology reassert themselves. Once again Wilson argues that brain architecture determines what people do socially – that war, aggression, morality, honor and hierarchy are part of “human nature.”

Rejecting kin selection

A major change, and one of the most satisfying parts of the book, is his rejection of kin selection as a motive force of social evolution, a theory he once defended strongly.

Kin selection assumed that natural selection acts on genes. A gene will be favored if it results in enhancing its own survival and reproduction, but it is not enough to look at the survival of the individual. If my brother and I each have 2 offspring, a shared gene would be doubled in the next generation. But if my brother sacrifices himself so that I might leave 5 offspring while he leaves none, our shared gene will increase 250%.

Therefore, argued the promoters of this theory, the fitness that natural selection increases has to be calculated over a whole set of kin, weighted by the closeness of their relationship. Mathematical formulations were developed to support this theory. Wilson found it attractive because it appeared to support sociobiology.

However, plausible inference is not enough to prove a theory. Empirical studies comparing different species or traits did not confirm the kin selection hypothesis, and a reexamination of its mathematical structure (such as the fuzziness of defining relatedness) showed that it could not account for the observed natural world. Wilson devotes a lot of space to refuting kin selection because of his previous support of it: it is a great example of scientific self-correction.

Does group selection explain social behaviour?

Wilson has now adopted another model in which the evolution of sociality is the result of opposing processes of ordinary individual selection acting within populations, and group selection acting between populations. He invokes this model account to for religion, morality, honor and other human behaviors.

He argues that individual selection promotes “selfishness” (that is, behavior that enhances individual survival) while group selection favors cooperative and “altruistic” behavior. The two forms of selection oppose each other, and that results in our mixed behaviors.

“We are an evolutionary chimera living on intelligence steered by the demands of animal instinct. This is the reason we are mindlessly dismantling the biosphere and with it, our own prospects for permanent existence.” [p.13]

But this simplistic reduction of environmental destruction to biology will not stand. Contrary to Wilson, the destruction of the biosphere is not “mindless.” It is the outcome of interactions in the noxious triad of greed, poverty, and ignorance, all produced by a socio-economic system that must expand to survive.

For Wilson, as for many environmentalists, the driver of ecological destruction is some generic “we,” who are all in the same boat. But since the emergence of classes after the adoption of agriculture some 8-10,000 years ago it is no longer appropriate to talk of a collective “we.”

The owners of the economy are willing to use up resources, pollute the environment, debase the quality of products, and undermine the health of the producers out of a kind of perverse economic rationality. They support their policies with theories such as climate change denial or doubting the toxicity of pesticides, and buttress it with legislation and court decisions.

Evolution and religion

The beginning and end of the book, a spirited critique of religion as possibly explaining human nature, is more straightforwardly materialist than the view supported by Stephen J. Gould, who argued that religion and science are separate magisteria that play equal roles in human wellbeing.

But Wilson’s use of evidence is selective.

For example, he argues that religion demands absolute belief from its followers – but this is true only of Christianity and Islam. Judaism lets you think what you want as long as you practice the prescribed rituals, Buddhism doesn’t care about deities or the afterlife.

Similarly he argues that creation myths are a product of evolution:

“Since paleolithic times … each tribe invented its own creation myths… No tribe could long survive without a creation myth… The creation myth is a Darwinian device for survival.” [p. 8]

But the ancient Israelites did not have an origin myth when they emerged as a people in the hills of Judea around 1250 B.C.E. Although it appears at the beginning of the Bible, the Israelites did not adapt the Book of Genesis from Babylonian mythology until four centuries after Deuteronomy was written, after they had survived 200 years as a tribal confederation, two kingdoms and the Assyrian and Babylonian conquests— by then the writing of scripture was a political act, not a “Darwinian device for survival.”

Biologizing war

In support of his biologizing of “traits,” Wilson reviews recent research that appears to a show a biological basis for the way people see and interpret color, for the incest taboo, and for the startle response – and then asserts that inherited traits include war, hierarchy, honor and such. Ignoring the role of social class, he views these as universal traits of human nature.

Consider war. Wilson claims that war reflects genes for group selection. “A soldier going into battle will benefit his country but he runs a higher risk of death than one who does not.” [p. 165]

But soldiers don’t initiate conflict. We know in our own times that those who decide to make war are not those who fight the wars – but, perhaps unfortunately, sterilizing the general staff of the Pentagon and of the CIA would not produce a more peaceful America.

The evidence against war as a biological imperative is strong. Willingness to fight is situational.

Group selection can’t explain why soldiers have to be coerced into fighting, why desertion is a major problem for generals and is severely punished, or why resistance to recruitment is a major problem of armies. In the present militarist USA, soldiers are driven to join up through unemployment and the promises of benefits such as learning skills and getting an education and self-improvement. No recruitment posters offer the opportunity to kill people as an inducement for signing up.

The high rates of surrender and desertion of Italian soldiers in World War II did not reflect any innate cowardice among Italians but a lack of fascist conviction. The very rarity of surrender by Japanese soldiers in the same war was not a testimony to greater bravery on the part of the Japanese but of the inculcated combination of nationalism and religion.

As the American people turned against the Vietnam war, increased desertions and the killing of officers by the soldiers reflected their rejection of the war.

The terrifying assaults of the Vikings during the middle ages bear no resemblance to the mellow Scandinavian culture of today, too short a time for natural selection to transform national character.

The attempt to make war an inherited trait favored by natural selection reflects the sexism that has been endemic in sociobiology. It assumes that local groups differed in their propensity for aggression and prowess in war. The victorious men carry off the women of the conquered settlements and incorporate them into their own communities. Therefore the new generation has been selected for greater military success among the men. But the women, coming from a defeated, weaker group, would bring with them their genes for lack of prowess, a selection for military weakness! Such a selection process would be self-negating.


Wilson also considers ethnocentrism to be an inherited trait: group selection leads people to favor members of their own group and reject outsiders.

The problem is that the lines between groups vary under different circumstances. For example, in Spanish America, laws governing marriage included a large number of graded racial categories, while in North America there were usually just two. What’s more, the category definitions are far from permanent: at one time, the Irish were regarded as Black, and the whiteness of Jews was questioned.

Adoption, immigration, mergers of clans also confound any possible genetic basis for exclusion.


Wilson draws on the work of Herbert Simon to argue that hierarchy is a result of human nature: there will always be rulers and ruled. His argument fails to distinguish between hierarchy and leadership.

There are other forms of organization possible besides hierarchy and chaos, including democratic control by the workers who elect the operational leadership. In some labor unions, leaders’ salaries are pegged to the median wage of the members. In University departments the chairmanship is often a rotating task that nobody really wants. When Argentine factory owners closed their plants during the recession, workers in fact seized control and ran them profitably despite police sieges.

Darwinian behavior?

Wilson argues that “social traits” evolved through Darwinian natural selection. Genes that promoted behaviors that helped the individual or group to survive were passed on; genes that weakened the individual or group were not. The tension between individual and group selection decided which traits would be part of our human nature.

But a plausible claim that a trait might be good for people is not enough to explain its origin and survival. A gene may become fixed in a population even if it is harmful, just by the random genetic changes that we know occur. Or a gene may be harmful but be dragged along by an advantageous gene close to it on the same chromosome.

Selection may act in different directions in different subpopulations, or in different habitats, or in differing environmental. Or the adaptive value of a gene may change with its prevalence or the distribution of ages in the population, itself a consequence of the environment and population heterogeneity.

For instance, Afro-Americans have a higher death rate from cancer than Euro-Americans. In part this reflects the carcinogenic environments they have been subjected to, but there is also a genetic factor. It is the combination of living conditions and genetics that causes higher mortality rates.

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Obviously I am not arguing that evolution doesn’t happen. The point is that we need a much better argument than just a claim that some genotype might be beneficial. And we need a much more rigorous understanding of the differences and linkages between the biological and social components of humanity’s nature. Just calling some social behavior a “trait” does not make it heritable.

In a book that attempts such a wide-ranging panorama of human evolution, there are bound to be errors. But the errors in The Social Conquest of Earth form a pattern: they reduce social issues to biology, and they insist on our evolutionary continuity with other animals while ignoring the radical discontinuity that made us productivores and divided us into classes.

“Nobres Selvagens” na Ilustríssima (Folha de S.Paulo) de domingo, 22 de fevereiro de 2015

Antropólogos, índios e outros selvagens

ilustração ANA PRATA

22/02/2015  03h05

RESUMO Livro do antropólogo Napoleon Chagnon que aborda suas pesquisas entre os ianomâmis é lançado no Brasil. Em entrevista, autor, que direcionou sua carreira para uma interpretação evolutiva do comportamento indígena, fala sobre suas conclusões e comenta a recepção, muitas vezes negativa, de sua obra entre seus pares.


Sobre Napoleon Chagnon, 76, há só uma unanimidade: trata-se do pesquisador mais polêmico da antropologia contemporânea.É

Nesta entrevista, o americano –que lança agora no Brasil o livro “Nobres Selvagens: Minha Vida entre Duas Tribos Perigosas: os Ianomâmis e os Antropólogos” pelo selo Três Estrelas, do Grupo Folha– afirma que a antropologia brasileira representa o que há de mais atrasado no pensamento anticientífico nessa área.

Chagnon critica ainda alguns brasileiros ligados à temática indígena, como o líder ianomâmi Davi Kopenawa, “manipulado por antropólogos e ONGs”, e o cineasta José Padilha, autor do documentário “Segredos da Tribo”, que “deveria se limitar a filmar Robocop”.

Ana Prata

Chagnon estudou os ianomâmis do Brasil e, principalmente, da Venezuela a partir de 1964 e ao longo de 35 anos, em 25 viagens que totalizaram 5 anos entre os índios. Foi o pioneiro no contato com várias tribos isoladas, que acredita serem uma janela para as sociedades pré-históricas nas quais o gênero Homo viveu por milhões de anos.

Foi visto com antipatia por diversos colegas antropólogos por propor explicações darwinianas para o comportamento dos índios –e dos humanos em geral– e ao escrever, em 1968, um livro em que tratava amplamente da violência entre os índios e no qual, desde o título, “Yanomamö: The Fierce People” (sem tradução no Brasil), chamava os ianomâmis de “o povo feroz”. Despertou inimizades ao se afastar dos colegas antropólogos, que acreditava mais interessados em fazer política do que ciência, e se aproximar de geneticistas.

Foi em 1988, porém, que causou a fúria dos colegas, ao publicar na revista “Science” um estudo mostrando que os homens ianomâmis com assassinatos no currículo eram justamente os que tinham mais mulheres e descendentes. Em termos biológicos, a violência masculina e certo egoísmo humano seriam estratégias reprodutivas bem-sucedidas, ideia que desagradou fortemente seus colegas das humanidades.

O antropólogo sempre defendeu que os índios que estudou guerreavam movidos por uma insaciável vontade de capturar mulheres, enquanto os livros tradicionais de antropologia diziam que a guerra primitiva tinha motivos como a escassez de alimentos ou de terra.

Chagnon diz que seus críticos são marxistas movidos pela ideologia de que os conflitos humanos se explicam pela luta de classes ou por disputas materiais, e não por motivos mais animalescos, como a busca por sucesso sexual.

Ele afirma que nenhum colega pôde apontar falhas nos dados publicados na “Science”. No entanto, antropólogos questionam seu procedimento não só nesse caso como em outros trabalhos (leia ao lado).

Em 2000, o jornalista Patrick Tierney publicou o livro “Trevas no Eldorado” (lançado no Brasil em 2002, pela Ediouro), acusando Chagnon e colegas, entre outras coisas, de terem espalhado sarampo deliberadamente entre os índios. As acusações foram investigadas pela Associação Americana de Antropologia, que inocentou os pesquisadores da grave acusação.

Na entrevista abaixo, feita por telefone, Chagnon trata ainda de temas como a higiene dos índios e os riscos da selva.


Folha – O antropólogo Eduardo Viveiros de Castro criticou na internet a publicação do seu livro no Brasil, dizendo que o sr. está ligado à “direita boçalmente cientificista”.

Napoleon Chagnon – A ideia de que o comportamento humano tem uma natureza biológica, moldada pela evolução, além da cultura, sofreu muita oposição nas últimas décadas de quem tem uma visão marxista. Está havendo uma mudança de paradigma, mas os antropólogos brasileiros são o último reduto dessa oposição e sempre tentaram impedir meu trabalho.

Marxistas não gostam de explicações que não envolvam a luta por recursos materiais. Para eles, isso explica tudo. Eles diziam, por exemplo, que a causa da guerra entre os ianomâmis era a escassez de proteína –uma tribo atacaria a outra em busca de carne. Nossas observações mostraram, porém, que não havia correlação. Eles tinham abundância de proteína; lutavam, na verdade, por mulheres.

Nos EUA, cientistas importantes, como meu grande amigo Steven Pinker e o professor Jared Diamond, escreveram recentemente livros demonstrando a relevância crescente da psicologia evolutiva.

Os antropólogos latino-americanos me atacam, mas não têm dados para rebater as conclusões que proponho, porque não gostam de trabalho de campo. Eles gostam de argumentos teóricos, de ficar sentados nas suas cadeiras na universidade fazendo ativismo. No entanto, para entender o mundo, você tem de coletar informações a fim de testar suas previsões e teorias. Essa é a base do método científico. A tendência pós-modernista é dizer que não há verdade, que tudo é social ou político. Isso é a morte da ciência.

Esses críticos dizem que sua visão dos ianomâmis é muito negativa. Citam trechos do seu livro em que o sr. descreve criticamente os hábitos de higiene dos índios, dizendo que eles espalhavam muco em tudo.

Tenho muitas críticas à minha própria civilização também, como o excesso de filas. Os ianomâmis não têm uma teoria da transmissão de doenças via germes. Então assoam o nariz na mão e passam no cabelo, nos outros, até na minha bermuda [risos]. A primeira coisa que quis aprender na língua deles foi “não encoste em mim, suas mãos estão sujas”, mas não adiantou. Você se acostuma.

Na verdade, você percebe que há coisas mais sérias com que se preocupar. A vida na tribo é perigosa. Há muitas cobras. Um bebê de uma tribo ianomâmi em que vivi sumiu, e os pais concluíram que a única explicação era que tivesse sido comido por uma anaconda. Há ainda muitos insetos, há onças, muitos outros incômodos.

Como é a sua relação com o líder ianomâmi Davi Kopenawa?

Ele é manipulado pelos seus mentores, seus conselheiros políticos, a maioria antropólogos e ONGs, que dizem a ele o que ele deve declarar. Ouço que muitos jornalistas brasileiros têm essa percepção, mas sabem que é impopular dizer isso em público.

As entrevistas com ele costumam ser mediadas por antropólogos.

Pois é. Veja, em uma das minhas visitas aos ianomâmis no Brasil, Kopenawa proibiu o piloto do meu avião de utilizar o combustível que tinha guardado perto de uma das tribos em que ele tinha influência. Ele queria a todo custo que eu ficasse isolado na floresta, fez isso deliberadamente. O piloto teve de conseguir combustível com outros colegas. Essa é uma das razões que me levaram a não ter uma opinião muito positiva a respeito dele.

Kopenawa critica vocês por não devolverem amostras de sangue que coletaram entre os índios em 1967 para estudos científicos na área de genética e que foram parar em bancos de universidades dos EUA.

Sou simpático a esse pedido. Mas essas amostras são 99% de tribos venezuelanas, não brasileiras. Seria horrível se entregássemos tal sangue para os ianomâmis brasileiros, como Kopenawa. Uma tribo ficaria muito assustada de saber que seus vizinhos têm o sangue de seus ancestrais, eles acreditam que isso poderia ser utilizado para fazer magia negra, por exemplo.

É importante dizer que, influenciadas por antropólogos, lideranças ianomâmis tornaram impossível hoje, para qualquer pesquisador, ir a suas tribos e coletar amostras de sangue; foram convencidos de que isso foi um crime terrível que cometemos. Dessa forma, nenhum pesquisador da área biomédica pode agora fazer estudos que envolvam coleta de amostras. Os ianomâmis vetaram para sempre qualquer pesquisa que possa beneficiar a sua saúde e dependa de exames de sangue.

Eu gosto muito dos ianomâmis. Fiquei muitos anos com eles. Eles merecem ser mais bem representados. É nítido que eles precisam de instituições que permitam acesso à medicina moderna, por exemplo. Eles precisam de ajuda.

De qualquer forma, eu não coletei amostras de sangue. Eu só ajudei os médicos a fazê-lo. Eu sou antropólogo. Não estou nem aí para o que acontecerá com as amostras de sangue congeladas nos EUA. Mas seria irresponsável se fossem entregues aos índios errados.

O sr. assistiu ao documentário “Os Segredos da Tribo” (2010), do brasileiro José Padilha?

Padilha mentiu para mim, foi muito desonesto. Ele disse que faria um filme equilibrado, mas nunca mencionou que as acusações feitas contra mim foram completamente desmentidas [pela Associação Americana de Antropologia]. Ele contratou um missionário que falava a língua ianomâmi para fazer as entrevistas com os índios. Esse missionário, amigo meu, depois veio me avisar que Padilha direcionava as entrevistas contra mim, que tudo era feito para criar a impressão de que os ianomâmis me odiavam. O filme é ridículo.

Além disso, Padilha lançou o filme e desapareceu, nunca respondeu às minhas ligações. Na apresentação do filme no festival de Sundance, ele não só não me convidou como chamou três antropólogos inimigos meus para debater. Um deles, Terence Turner, que teve participação ativa na elaboração do filme, me acusava de ser o Mengele das tribos ianomâmis. É doentio. Padilha deveria se limitar a filmar “Robocop”.

Depois de trabalhar muitos anos nas universidades do Michigan e de Missouri, o sr. agora é professor aposentado. Aposentou-se também da pesquisa científica?

Não. Continuo trabalhando com os dados que coletei nas tribos ao longo desses anos todos. Estou para publicar vários artigos em revistas importantes, como a “Science”, mostrando o impacto de conceitos caros à biologia, como o parentesco, na organização das tribos ianomâmis. Se os antropólogos brasileiros não gostam do meu trabalho, ainda não viram nada [risos]. No caso do público brasileiro, espero que os leitores encontrem no meu livro agora publicado uma melhor compreensão da natureza humana, seja no comportamento dos povos indígenas ou no de um vizinho.

RICARDO MIOTO, 25, é editor de “Ciência” e “Saúde” da Folha.

ANA PRATA, 34, é artista plástica.

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Livro contribui para distanciar ciências humanas e biológicas

André Strauss

22/02/2015  03h09

Por sua alegada coragem em sustentar hipóteses fundamentadas em princípios darwinianos, o antropólogo americano Napoleon Chagnon, que dedicou sua carreira a estudar a violência entre os índios ianomâmis, apresenta-se em “Nobres Selvagens” [trad. Isa Mara Lando, Três Estrelas, 608 págs., R$ 89,90] como vítima dos mais diversos ataques e preconceitos por parte de seus pares.

Os antropólogos culturais, os religiosos salesianos, os ativistas políticos e os próprios ianomâmis são retratados como grupos ferozes ou biofóbicos. Já Chagnon seria apenas um inocente antropólogo de Michigan. A tese não convence.

Embora o antropólogo pretenda ser um expoente da síntese entre biologia e antropologia, suas proposições são bastante limitadas e, muitas vezes, equivocadas. Exemplo disso é partir do princípio de que uma sociedade não contatada é o mesmo que uma sociedade não impactada, atribuindo aos ianomâmis condição análoga à de sociedades paleolíticas. Propor um contratualismo hobbesiano baseado na luta por mulheres também soa ingênuo.

Em seu livro, Napoleon Chagnon insiste na noção anacrônica de “ciência pura”, desmerecendo a militância pró-indígena dos antropólogos brasileiros como um capricho do politicamente correto.

Mesmo reconhecendo-se que em diversas ocasiões seus detratores exageraram, esse tipo de postura maniqueísta do autor não contribui para a necessária superação dos conflitos epistemológicos e políticos que seguem existindo, ainda que ligeiramente mitigados, entre as chamadas ciências humanas e biológicas.

Um famoso filósofo darwiniano certa vez reconheceu que as teorias antropológicas de cunho biológico têm, inegavelmente, o péssimo hábito de atrair os mais indesejáveis colaboradores. Daí a importância da cada vez maior politização dos bioantropólogos e o movimento explícito por parte deles para impedir que esses associados participem de seus círculos.

Ainda assim, provavelmente Chagnon não é culpado das acusações mais graves que lhe foram imputadas, tal como a de disseminar propositalmente uma epidemia de sarampo entre os indígenas ou a de incentivar, por escambo, que eles declarassem guerras uns contra os outros a fim de que ele pudesse incluir as cenas de violência em um documentário que estava produzindo.

Por outro lado –e isso não se pode negar a Chagnon–, é verdade que as humanidades muitas vezes parecem apresentar aquilo que se convencionou chamar de um “desejo irresistível para a incompreensão”, resultando em acusações injustas e de caráter persecutório.

Algumas décadas atrás, ainda era possível negar a relevância de campos como a genética comportamental, a ecologia humana, a neurociência cognitiva ou a etologia de grandes símios. Atualmente, entretanto, qualquer tentativa de mantê-los fora da esfera antropológica é um exercício vão.

Mais importante, a estratégia comumente utilizada no passado de atrelar os desdobramentos oriundos dessas áreas a implicações nefastas para a dignidade humana, torna-se, além de injusta, muito perigosa.

Juntos, antropólogos e biólogos precisam elaborar uma narrativa capaz de ressignificar esses novos elementos através de uma ótica benigna. Afinal, eles passarão, inevitavelmente, a fazer parte do arcabouço teórico de ambas as disciplinas.

ANDRÉ STRAUSS, 30, é antropólogo do Laboratório de Estudos Evolutivos Humanos da USP e do Instituto Max Planck de Antropologia Evolutiva, na Alemanha.

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Trajetória do pesquisador é marcada por querelas

Marcelo Leite

22/02/2015  03h13

Não é trivial resumir as objeções que a antropologia cultural levanta contra Napoleon Chagnon. A controvérsia tem quase meio século, e a tarefa fica mais complicada quando muitos dos antropólogos relevantes do Brasil se recusam a dar entrevistas sobre o caso.

O panorama se turvou de vez em 2000, com o livro “Trevas no Eldorado”. Nele o jornalista Patrick Tierney acusava Chagnon e o médico James Neel de, em 1968, terem causado uma epidemia de sarampo entre os ianomâmis da Venezuela e experimentado nos índios um tipo perigoso de vacina, além de negar-lhes socorro médico.

Chagnon e Neel foram depois inocentados dessas acusações graves. Bruce Albert, antropólogo e crítico de Chagnon que trabalha há 36 anos com os ianomâmis, já escreveu sobre a ausência de fundamento das alegações de Tierney.

Ana Prata

Nem por isso Albert deixa de assinalar sérios erros éticos da dupla. Para ele, os ianomâmis foram usados, sem saber, como grupo de controle para estudos sobre efeitos de radiação nuclear no sangue de sobreviventes de bombardeios em Hiroshima e Nagasaki.

Chagnon, capataz de Neel na expedição, obtinha amostras de sangue em troca de machados, facões e panelas. Embora essa prática perdurasse nos anos 1960-70, Albert ressalva que regras exigindo consentimento informado já vigiam desde 1947 (Código de Nuremberg) e 1964 (Declaração de Helsinque).

Os reparos ao trabalho de Chagnon abarcam também a própria ciência. Ele se diz superior aos antropólogos tradicionais, que acusa de relativistas pós-modernos, xingamento comum nos setores cientificistas da academia americana.

A polêmica teve início com o livro “Yanomamö: The Fierce People”, em que Chagnon apresentou sua tese de que ianomâmis são uma relíquia ancestral da espécie humana: selvagens com compulsão pela guerra como forma de obter mulheres, escassas devido à prática do infanticídio feminino.

Os críticos da etnografia de Chagnon afirmam que ele nunca comprovou o infanticídio seletivo. Com efeito, a explicação foi abandonada em outros estudos, como um famigerado artigo de 1988 no periódico científico “Science”.

O trabalho recorre a dados demográficos coletados por Chagnon para corroborar sua noção, bem ao gosto da sociobiologia, de que os homens mais violentos eram os que tinham mais mulheres e filhos. Esses seriam os que os ianomâmis chamam “unokai” –segundo o autor, os mais temidos no grupo (e, por isso, mais prolíficos).

Albert, Jacques Lizot e outros antropólogos consideram que ele misturou alhos com bugalhos. “Unokai” não seria um atributo individual, mas o estado de impureza (simbólica) daquele que mata alguém com armas ou feitiçaria, ou mesmo só entra em contato com o sangue de cadáveres de inimigos.

Além disso, em incursões contra outras aldeias, os guerreiros muitas vezes dão golpes e flechadas em adversários já mortos. Isso os tornaria “unokai”, não homicidas.

Os mais admirados não seriam esses, mas os “waitheri”, algo como “valorosos”, que se distinguem não só pela valentia, mas também pela capacidade de liderar, de falar bem, até pelo humor.

Não bastasse isso, os críticos apontam manipulação de números. Para inflar seus dados e chegar a 44% de homens que teriam participado de mortes e tinham até o triplo de filhos na comparação com os não “unokai”, Chagnon teria excluído da amostra jovens de 20 a 25 anos e homens mortos –violentos ou não, com ou sem filhos.

Em fevereiro de 2013, o antropólogo Marshall Sahlins renunciou à Academia Nacional de Ciências dos EUA após o ingresso de Chagnon. Num artigo em que explicava o ato, defendeu que um antropólogo alcança entendimento superior de outros povos quando toma seus integrantes como semelhantes –e não objetos naturais, “selvagens”, ao modo de Chagnon.

“É claro que esse não é o único meio de conhecer os outros. Podemos também utilizar nossa capacidade simbólica para tratá-los como objetos físicos”, escreveu. “Mas não obteremos o mesmo conhecimento dos modos simbolicamente ordenados da vida humana, do que é a cultura, ou até a mesma certeza empírica.”

MARCELO LEITE, 57, é repórter especial e colunista da Folha.

*   *   *

Morte sistemática de Ianomâmis é um tabu

Leão Serva

23/02/2015  02h00

Folha publicou com grande destaque na edição de domingo (22) a notícia do lançamento do livro “Nobres Selvagens” (pela Três Estrelas, selo do Grupo Folha), de autoria do antropólogo norte-americano Napoleon Chagnon. Títulos na capa e no caderno da Ilustríssima chamaram a obra de “livro tabu”.

Trata-se de um exagero baseado no discurso persecutório do autor, que sempre responde às críticas a seu trabalho com alegações de perseguição pessoal ou boicote. Uma pesquisa no Google News apresenta 872 respostas com notícias sobre o antropólogo e 64 referências ao livro, incluindo veículos de grande prestígio internacional como “The New York Times” e “Washington Post”.

No Brasil, certamente a obra não foi tema de reportagens simplesmente porque não havia sido lançada.

Na edição, textos de Marcelo Leite e André Strauss compilam as principais fragilidades apontadas pelos críticos da obra de Chagnon.

Uma bem importante, no entanto, não foi mencionada: o antropólogo dá pouca importância ao caráter simbólico das expressões da cultura que aparecem nos depoimentos de índios (e de brancos também, é bom que se diga), o que o leva a tomar o que ouve literalmente. Assim, em sua entrevista, é quase infantil a descrição dos perigos de uma aldeia Ianomâmi. Os medos que Chagnon menciona que concentrariam a atenção dos índios para longe dos cuidados médicos (risco de onças e cobras) são próprios de um alienígena. Já os índios criam cobras em casa para comer ratos; sabem que onças têm medo dos homens e, em situações raras, quando se aproximam furtivamente da periferia da aldeia para tocaiar uma criança, logo são capturadas pelos índios, como eu mesmo testemunhei. Não quer dizer que não haja medo, mas o antropólogo o amplifica para reforçar o estereótipo de atraso.

A história de que um casal ianomâmi teria atribuído o desaparecimento de seu filhinho a uma anaconda esfomeada é bizarra: o bebê na aldeia não fica um minuto longe dos outros e uma sucuri no lento processo de engolir uma criança seria vista por dúzias de pessoas e morta. Chagnon certamente não entendeu o que lhe foi dito ou tomou por verdade uma mentira (vale lembrar que um “civilizado” banqueiro suíço também mente).

Em texto mais antigo, Chagnon apontava o gesto de bater no peito, comum em festas de ianomâmis como expressão da violência da cultura desses grupos. Ora, o mesmo movimento pode ser encontrado diariamente em culturas mais “evoluídas”, segundo seu critério, das grandes cidades da Europa e dos EUA (nas missas católicas quando se diz “Minha culpa, minha culpa, minha máxima culpa”) à Mesopotâmia, berço das civilizações (onde soldados contemporâneos reproduzem o gesto antes de ataques de infantaria). Chagnon não leva em conta o alicerce básico do estudo da antropologia, que as culturas humanas são simultâneas, embora diferentes na expressão material.

Por fim, para desfazer as críticas feitas pelo líder Davi Kopenawa, criou a história de que ele é manipulado por antropólogos. A Folha parte dessa premissa para questionar Chagnon: “As entrevistas com ele costumam ser mediadas por antropólogos”, ao que o autor diz: “Pois é”, e segue sua catilinária.

Trata-se de uma inverdade que qualquer repórter que fale bem português ou ianomâmi pode comprovar. Eu entrevistei Kopenawa três vezes em épocas e lugares diferentes, duas delas sem aviso prévio. Me aproximei, pedi para falar e conversamos sem mediação. Uma vez, em seu escritório em Boa Vista, ele pediu que outras pessoas (que eu não conhecia, índios e brancos) saíssem da sala para ser entrevistado. Fala fluentemente um português simples (de brasileiro não universitário) com forte sotaque. É preciso ter calma e prestar atenção, por vezes pedir que repita para entender a pronúncia de algumas palavras.

A última vez que o encontrei foi numa entrevista para a revista Serafina, com hora marcada. Também ficou só, enquanto eu estava acompanhado da jovem fotógrafa Helena Wolfenson, da Folha. É possível que estrangeiros que falem mal ou não falem português precisem de tradutor. E são certamente raras as pessoas que falam português, ianomâmi e línguas estrangeiras. Talvez daí a história de que ele se faça acompanhar de “antropólogos” ou gente de ONG.


O que de fato é um “tabu” (aquilo de que não se fala) na imprensa brasileira é o lento processo de abandono dos Ianomâmi à morte, em curso por incompetência ou (depois de tanto tempo) decisão do governo federal.

Como noticiei nesta coluna em maio do ano passado, as mortes de Ianomâmi por problemas de saúde cresceram nos dois governos do PT (Lula e Dilma). Muitas das doenças são simples de evitar, como provam as estatísticas da segunda metade dos anos 1990.

O aumento se deve em grande medida à interrupção dos trabalhos de medicina preventiva nas aldeias e ao crescimento dos gastos com transporte dos doentes das aldeias para a capital de Roraima, Boa Vista.

A maior parte dos custos do Ministério da Saúde com a saúde indígena em Roraima tem sido despejada em frete de aviões para levar índios a Boa Vista. São poucas as empresas de táxi aéreo, as mesmas que levam políticos locais em seus deslocamentos.

Em janeiro do ano passado, quando a entrevistei, a coordenadora do Ministério da Saúde para as áreas indígenas de Roraima, Maria de Jesus do Nascimento, explicou o aumento das mortes dizendo: “Não, dinheiro não falta… Foi problema de gestão, mesmo”.

Na área Ianomâmi, uma médica cubana do programa Mais Médicos se desesperava: “Não tenho antibióticos, não tenho oxigênio, não tenho equipamentos”. Eu perguntei o que fazia: “Não quero mas sou forçada a mandar os índios de avião para Boa Vista”. O meio se tornou o fim. A saúde dos índios se tornou desculpa para enriquecer as empresas de táxi aéreo.

Quem procura no mesmo Google News notícias sobre as mortes de Ianomâmi pela improbidade dos órgãos de saúde local só encontra quatro notícias, uma delas do espanhol El País, as demais noticiando os protestos dos índios e um debate no Congresso.

Esse genocídio lento e discreto é o verdadeiro tabu.

Another Weird Story: Intentional, Post-Intentional, and Unintentional Philosophy (The Cracked Egg)

JANUARY 18, 2015

I was a “2e” kid: gifted with ADHD but cursed with the power to ace standardized tests. I did so well on tests they enrolled me in a Hopkins study, but I couldn’t remember to brush my hair. As if that wasn’t enough, there were a lot of other unusual things going on, far too many to get into here. My brain constantly defied people’s expectations. It was never the same brain from day to day. I am, apparently, a real neuropsychiatric mystery, in both good and bad ways. I’m a walking, breathing challenge to people’s assumptions and perceptions. Just a few examples: the assumption that intelligence is a unitary phenomenon, and the perception that people who think like you are smarter than those who think differently. Even my reasons for defying expectations were misinterpreted. I hated the way people idolized individuality, because being different brought me only pain. People mistook me for trying to be different. Being different is a tragedy!

And it got weirder: I inherited the same sociocognitive tools as everyone else, so I made the same assumptions. Consequently, I defied even my own expectations. So I learned to mistrust my own perceptions, always looking over my shoulder, predicting my own behavior as if I were an outside observer. I literally had to re-engineer myself in order to function in society, and that was impossible to do without getting into some major philosophical questions. I freely admit that this process has taken me my entire life and only recently have I had any success. I am just now learning to function in society–I’m a cracked egg. Cracked once from outside, and once from inside. And just now growing up, a decade late.

So it’s no surprise that I’m so stuck on the question of what people’s brains are actually doing when they theorize.

I stumbled onto R. Scott Bakker’s theories after reading his philosophical thriller, Neuropath. Then I found his blog, and I was blown away that someone besides me was obsessed with the role of ingroup/outgroup dynamics in intellectual circles. As someone with no ingroup (at least not yet), it’s very refreshing. But what really blew my mind was that he had a theory of cognitive science that could explain many of my frustrating experiences: the Blind Brain Theory, or BBT.

The purpose of this post is not to explain BBT, so you’ll have to click the link if you want that. I’ll go more into depth on the specifics of BBT later, but for a ridiculously short summary: it’s a form of eliminativism. Eliminativism is the philosophical view that neuroscience reveals our traditional conceptions of the human being, like free will, mind, and meaning, to be radically mistaken. But BBT is unique among eliminativisms in its emphasis of neglect: the way in which blindness, or lack of information, actually *enables* our brains to solve problems, especially the problem of what we are. And from my perspective, that makes perfect sense.

BBT is a profoundly counterintuitive theory that cautions us against intuition itself. And ironically, it substantiates my skeptical intuitions.  In short, it shows I’m not the only one who has no clue what she’s doing. If BBT is correct, non-neurotypical individuals aren’t really “impaired.” They simply fit differently with other people. Fewer intersecting lines, that’s all. Bakker has developed his theory further since he published this paper, building on his notion of post-intentional theory (see here for a more general introduction). BBT has stirred up quite a lot of drama.

While we all argue over BBT, absorbed in defending our positions, I feel like an outsider, even among people who understand ingroups. Why? Because most of the people in the debate seem to be discussing something hypothetical, something academic. For me, as I’ve explained, the question of intentionality is a question of everyday life. So I can’t shirk my habit of wondering about biology: what’s going on in the brains of intentionalists? What’s going on in the brains of post-intentionalists? And what’s going on inside my own brain? Bakker would say this is precisely the sort of question a post-intentionalist would ask.

But what happens if the post-intentionalist has never done intentional philosophy? Allow me to explain, with a fictionalized example from my own experience. I use the term “intentional” in both an everyday and philosophical sense, interchangeably:

Intentional, Post-Intentional, and Unintentional Philosophy

Imagine you’re an ordinary person. You just want to get on with your life, but you have a terminal illness. It’s an extremely rare neuropsychiatric syndrome: in order to recover, you must solve an ancient philosophical question. You can’t just come up with any old answer. You actually have to prove you solved it, and convince everyone alive you at least have to convince yourself that you could convince anyone whose counterargument could possibly sway you. You’re skeptical to the marrow, and very good at Googling.

Remember, this is a terminal illness, so you have limited time to solve the problem.

In college, philosophy professors said you were a brilliant student. Plus, you have a great imagination from always being forced to do bizarre things. So naturally, you think you can solve it.

But it takes more time than you thought it would. Years more time. Enough time that you turn into a mad hermit. Your life collapses around you and you’re left with no friends, family, or work. But your genes are really damn virulent, and they simply don’t contain the stop codons for self-termination, so you persist.

And finally, after many failed attempts, you cough up something that sticks. An intellectual hairball.

But then the unimaginable happens: you come across a horrifying argument. The argument goes that when it comes to philosophy, intention matters. If your “philosophy” is just a means to survive, it is not philosophy at all; only that which is meant as philosophy can be called philosophical. So therefore, your solution is not valid. It is not even wrong.

So, it’s back to the drawing board for you. You have to find a new solution that makes your intention irrelevant. A solution that satisfies both the intentional philosophers, who do philosophy because they want to, and the unintentional philosophers who do it because they are forced to.

And then you run across something called post-intentional philosophy. It seems like a solution, but…

But post-intentional philosophy, as you see, requires a history: namely, a history of pre-post-intentional philosophy. Or, to oversimplify, intentional philosophy! The kind people do on purpose, not with a gun to their head.

You know that problems cannot be solved from the same level of consciousness that created them, so you try to escape what intentional and post-intentional philosophy share: theory. You think you can tackle your problem by finding a way out of theory altogether. A way that allows for the existence of all sorts of brains generating all sorts of things, intentional, post-intentional, and unintentional. A nonphilosophy, not a Laruellian non-philosophy. That way must exist, otherwise your philosophy will leave your very existence a mystery!

What do you do?

Are Theory and Practice Separate? Separable? Or something completely different?

Philosophy is generally a debate, but as an unintentional thinker I can’t help but remain neutral on everything except responsiveness to reality (more on that coming later). In this section I am attempting neither to support nor to attack it, but to explore it.

Bakker’s heuristic brand of eliminativism appears to bank on the ability to distinguish between the general and the specific, the practical and the theoretical. Correct me if I am wrong.

As the case of the “unintentional philosopher” suggests, philosophers themselves are counterexamples to the robustness of this distinction, just like people with impaired intentional cognition offer counterexamples that question folk psychology. If BBT is empirically testable, the practice-vs-theory distinction must remain empirically testable. We should be able to study everyday cognition (“Square One”) independently of theoretical cognition (“Square Two”) and characterize the neurobiological relationship of the two as either completely modular, somewhat modular, or somewhere in between. We should also be able to predict whether someone is an intentionalist or a post-intentionalist by observing their brains.

From a sociobiological perspective, one possibility is that Bakker is literally trying to hack philosophers’ brains: to separate the neural circuitry that connects philosophical cognition with daily functionality.

If that were the case, their disagreement would come as no surprise.

But my real point here, going back to my struggles with my unusual neurobiology, is that I am personally, neurologically, as close to “non-intentional” as people get. And that presents a problem for my ability to understand any of these philosophical distinctions regarding intentionality, post-intentionality, etc. But just as a person with Aspergers syndrome is forced to intellectually explore the social, my relative deficit of intentionality has simultaneously made it unavoidable–necessary for me to explore intentionality.  My point about theory and practice is to ask whether this state of affairs is “just my problem,” or whether it says something about the entire project of theory.

If nothing else, it certainly questions the assumption that the doctor is never the patient, that the post-intentional theorist is always, necessarily some sort of detached intellectual observer with no deviation from the intentional norm in his own neurobiology.

Come back later for a completely different view…

Parasite-schizophrenia connection: One-fifth of schizophrenia cases may involve the parasite T. gondii (Science Daily)

Date: October 29, 2014

Source: University of Pennsylvania

Summary: Many factors, both genetic and environmental, have been blamed for increasing the risk of a diagnosis of schizophrenia. Some, such as a family history of schizophrenia, are widely accepted. Others, such as infection with Toxoplasma gondii, a parasite transmitted by soil, undercooked meat and cat feces, are still viewed with skepticism. A new study used epidemiological modeling methods to determine the proportion of schizophrenia cases that may be attributable to T. gondii infection. The work suggests that about one-fifth of cases may involve the parasite.

The parasite T. gondii has been shown to alter behavior in rodents. Smith’s study supports a link to schizophrenia in humans. Credit: Image courtesy of University of Pennsylvania

Many factors, both genetic and environmental, have been blamed for increasing the risk of a diagnosis of schizophrenia. Some, such as a family history of schizophrenia, are widely accepted. Others, such as infection with Toxoplasma gondii, a parasite transmitted by soil, undercooked meat and cat feces, are still viewed with skepticism.

A new study by Gary Smith, professor of population biology and epidemiology at the University of Pennsylvania’s School of Veterinary Medicine, used epidemiological modeling methods to determine the proportion of schizophrenia cases that may be attributable to T. gondii infection. The work, published in the journal Preventive Veterinary Medicine, suggests that about one-fifth of cases may involve the parasite.

“Infection with Toxoplasma is very common, so, even if only a small percentage of people suffer adverse consequences, we could be talking about problems that affect thousands and thousands of people,” Smith said.

In the United States, just over a fifth of the population is infected with T. gondii. The vast majority aren’t aware of it. But there are some populations that need to be concerned. For example, if a woman becomes infected for the first time during pregnancy, her fetus can die or suffer serious developmental problems. People with HIV or other diseases that weaken the immune system are susceptible to a complication of T. gondii infection called toxoplasmic encephalitis, which can be deadly.

Though the medical community has long believed that most healthy people suffer no adverse effects from a T. gondii infection, recent studies have found evidence of worrisome impacts, including an association with schizophrenia because the parasite is found in in the brain as well as in muscles. Other work has shown that some antipsychotic drugs can stop the parasite from reproducing. In addition, field and laboratory studies in mice, rats and people have shown that infection with T. gondiitriggers changes in behavior and personality.

To further investigate this connection, Smith sought to calculate the population attributable fraction, or PAF, a metric epidemiologists use to determine how important a risk factor might be. In this case, Smith explained that the PAF is “the proportion of schizophrenia diagnoses that would not occur in a population if T. gondii infections were not present.”

The usual method of calculating the PAF was not well suited to examining the link between schizophrenia and T. gondii, because some of the variables are constantly in flux. For example, the proportion of people infected by T. gondii increases with age. Using a standard epidemiological modeling format, but taking into account all of the age-related changes in the relevant factors, Smith found the average PAF during an average lifetime to be 21.4 percent.

“In other words, we ask, if you could stop infections with this parasite, how many cases could you prevent?” Smith said. “Over a lifetime, we found that you could prevent one-fifth of all cases. That, to me, is significant.”

Smith noted that in some countries, the prevalence of T. gondii infection is much higher than in the U.S., and these countries also have a higher incidence of schizophrenia.

People with schizophrenia have greatly reduced life expectancies, and many are unable to work. Family members may also leave the workforce to care for relatives with the disease. For these reasons and others, schizophrenia acts as a large drain on the economy, responsible for $50 to $60 billion in health-care expenditures in the U.S. each year.

“By finding out how important a factor T. gondii infection is, this work might inform our attitude to researching the subject,” Smith said. “Instead of ridiculing the idea of a connection between T. gondii and schizophrenia because it seems so extraordinary, we can sit down and consider the evidence. Perhaps then we might be persuaded to look for more ways to reduce the number of people infected with Toxoplasma.”

The study was supported by the University of Pennsylvania School of Veterinary Medicine.

Journal Reference:

  1. Gary Smith. Estimating the population attributable fraction for schizophrenia when Toxoplasma gondii is assumed absent in human populations.Preventive Veterinary Medicine, 2014; DOI: 10.1016/j.prevetmed.2014.10.009

Cientistas descobrem dois genes relacionados a crimes violentos (Zero Hora)

A característica estava presente em 10% dos 900 criminosos finlandeses analisados em estudo de instituto sueco

Mais um estudo científico conclui que a genética pode estar relacionada a crimes violentos. Desta vez, a partir da análise de quase 900 criminosos na Finlândia, pesquisadores descobriram dois genes que ampliaram em 13 vezes as chances de a pessoa ter comportamento violento repetidamente.

Veja a matéria completa em:

(Zero Hora)

In Amazon wars, bands of brothers-in-law (University of Utah)

[Chagnon is restless.Gosh]


Contact: Lee J. Siegel

How culture influences violence among the Amazon’s ‘fierce people’

IMAGE: In this mid-1960s photo, men from two Yanomamo villages in the Amazon engage in nonhostile combat to determine the strength and fighting prowess of potential alliance partners. A new study…

Click here for more information.

SALT LAKE CITY, Oct. 27, 2014 – When Yanomamö men in the Amazon raided villages and killed decades ago, they formed alliances with men in other villages rather than just with close kin like chimpanzees do. And the spoils of war came from marrying their allies’ sisters and daughters, rather than taking their victims’ land and women.

Those findings – which suggest how violence and cooperation can go hand-in-hand and how culture may modify any innate tendencies toward violence – come from a new study of the so-called “fierce people” led by provocative anthropologist Napoleon Chagnon and written by his protégé, University of Utah anthropologist Shane Macfarlan.

Macfarlan says the researchers had expected to find the Yanomamö fought like “bands of brothers” and other close male kin like fathers, sons and cousins who live in the same community and fight nearby communities. That is how fights are conducted by chimpanzees – the only other apes besides humans that form coalitions to fight and kill.

Instead, “a more apt description might be a ‘band of brothers-in-law,'” in which Yanomamö men ally with similar-age men from nearby villages to attack another village, then marry their allies’ female kin, Macfarlan, Chagnon and colleagues write in the study, published this week in the journal Proceedings of the National Academy of Sciences.

The study provides a mechanism to explain why Yanomamö warriors in a 1988 Chagnon study had more wives and children than those who did not kill.

“We are showing these guys individually get benefits from engaging in killing,” Macfarlan says. “They’re getting long-term alliance partners – other guys they can trust to get things done. And they are getting marriage opportunities.”

Since his 1968 book “Yanomamö: The Fierce People,” Chagnon has been harshly criticized by some cultural anthropologists who claim he places undue emphasis on genes and biology as underpinnings of human violence, based on his 1964-1993 visits to the Yanomamö. Defenders such as Macfarlan say Chagnon takes a much more balanced view, and that “it’s never a genes-versus-culture argument. They operate in tandem.”

Chagnon got what was seen as vindication in 2012 when he was elected to the prestigious National Academy of Sciences. The new study, with Macfarlan as first author and Chagnon as senior author – is Chagnon’s inaugural PNAS article as a member.

Macfarlan joined the University of Utah faculty this year an assistant professor of anthropology. He worked as Chagnon’s postdoctoral fellow at the University of Missouri from January 2013 to June 2014. Chagnon and Macfarlan conducted the study with two Missouri colleagues: anthropologists Robert S. Walker and Mark V. Flinn.

Models of Warfare

The Yanomamö – hunters and farmers who live in southern Venezuela and northern Brazil – once gained social status as “unokai” for killing.

Up to 20 Yanomamö (pronounced yah-NO-mama, but also spelled Yanomami or Yanomama) would sneak up on another village at dawn, “shoot the first person they saw and then hightail back home,” Macfarlan says. Some Yanomamö men did this once, some up to 11 times and some never killed. (Data for the study, collected in the 1980s, covered somewhat earlier times when spears, bows and arrows were the primary weapons.)

IMAGE: University of Utah anthropologist Shane Macfarlan, shown here, is first author of a new study with provocative anthropologist Napoleon Chagnon about the Yanomamo, or so called ‘fierce people’ of…

Click here for more information.

Macfarlan says the classic debate has been, “does warfare in small-scale societies like the Yanomamö resemble chimpanzee warfare?” – a theory known as the “fraternal interest group” model, in which bands of brothers, fathers, sons and paternal uncles all living in the same community fight other similar communities.

The new study asked whether Yanomamö killing follows that model or the “strategic alliance model,” which the researchers dub the “band of brothers-in-law” model. This model – supported by the study’s findings – indicates that Yanomamö men form alliances not with close kin from the same community, but with men from other communities. After killing together, a bond is formed and they often marry each other’s daughters or sisters and move into one or the other’s village or form a new village.

“When we started off this project, we all assumed it would be the chimpanzee-like model. But in human groups we have cultural rules that allow us to communicate with other communities. You certainly don’t see chimpanzees doing this.”

Is the study a retreat from what Chagnon’s critics see as too much focus on genetic and biological underpinnings of violence? Macfarlan says no, that Chagnon “has never been as all-biology as people have painted him. Most of his published research shows how unique cultural rules make the Yanomamö an interesting group of people.”

Earlier research suggested that for chimps, warfare is adaptive in an evolutionary sense, and that it also benefits small-scale human societies. The new study asked, “If warfare is adaptive, in what way do the adaptive benefits flow?” Macfarlan says.

“Some people, myself included, said, to the victor goes the spoils, because if you conquer another territory, you might take their land, food or potentially their females.”

But the new study indicates “the adaptive benefits are the alliances you build by perpetrating acts of warfare,” he adds. “It’s not that you are taking land or females from the vanquished group, but for the Yanomamö, what you acquire is that you can exchange resources with allies, such as labor and, most importantly, female marriage partners.”

The study’s findings that the Yanomamö form strategic alliances to kill suggest that “our ultracoooperative tendencies tend to go hand-in-hand with our ultralethal tendencies,” Macfarlan says. “We show a relationship between cooperation and violence at a level unseen in other organisms.” That may seem obvious for allied nations in modern wars, but “we’re saying that even in small-scale societies this is the case.”

IMAGE: Men from one Yanomamo village in the Amazon ‘dance’ in a neighboring village to show off their military prowess, weaponry and group cohesion after they were invited to a…

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How the Study was Conducted

The new study analyzed data collected by Chagnon in the 1980s, when about 25,000 Yanomamö lived in about 250 villages ranging from 25 to 400 people.

The study examined 118 Yanomamö warriors or unokai who had killed a total of 47 people by forming raiding parties of two to 15 men. The researchers analyzed the relationships between every possible pair of men in those raiding parties. Among the 118 unokai men, there were 509 possible pairs. Macfarlan says the findings revealed surprises about the relationship between co-unokai – pairs of men who kill together:

  • Only 22 percent of men who kill together were from the same lineage.
  • Only 34 percent of co-unokai pairs were from the same place of birth. “Guys who come from different places of birth are more likely to kill together.”
  • Among co-killers known to be related, a majority were related on their mother’s side rather than their father’s side – more evidence of forming alliances beyond the immediate paternal kinship group. In Yanomamö culture, true kin are viewed as being on the paternal side, while maternal relatives are seen as belonging to another social group.
  • The Yanomamö preferred forming coalitions with men within a median of age difference of 8 years. “The more similar in age, the more likely they will kill multiple times,” Macfarlan says.
  • Of the 118 unokai, 102 got married in a total of 223 marriages to 206 women. Of married killers, 70 percent married at least one woman from the same paternal line as an ally in killing. And “the more times they kill together, the more likely they are going to get marriage partners from each other’s family line,” Macfarlan says.
  • As a result, “The more times the guys kill together, the more likely they are to move into the same village later in life, despite having come from different village.”

The study found allies-in-killing often are somewhere between maternal first and second cousins, Macfarlan says. Under Yanomamö rules, a man’s ideal marriage partner is a maternal first cousin, who would be the offspring of your mother’s brother. He says Yanomamö rules allow marriage to a maternal first cousin, but not a paternal first cousin.

Despite debate over the biological roots of deadly coalitions in chimps and humans, the new study shows how culture can make it “uniquely human” because if Yanomamö men “kill together, they are plugged into this social scene, this marriage market,” Macfarlan says. “They are playing the game of their culture.”

Chimpanzees Are Rational, Not Conformists, Researchers Find (Science Daily)

Dec. 13, 2013 — Chimpanzees are sensitive to social influences but they maintain their own strategy to solve a problem rather than conform to what the majority of group members are doing. However, chimpanzees do change their strategy when they can obtain greater rewards, MPI researchers found. The study was published in PLOS ONE on November 28, 2013.

Chimpanzees are sensitive to social influences but they maintain their own strategy to solve a problem rather than conform to what the majority of group members are doing. (Credit: Image courtesy of Max-Planck-Gesellschaft)

Chimpanzees are known for their curious nature. They show a rich palette of learning behaviour, both individually and socially. But they are also rather hesitant to abandon their personal preferences, even when that familiar behaviour becomes extremely ineffective. Under which circumstances would chimpanzees flexibly adjust their behaviour? Edwin van Leeuwen and colleagues from the MPI’s for Psycholinguistics and Evolutionary Anthropology conducted a series of experiments in Germany and Zambia to answer this question.

Wooden balls for peanuts

The researchers studied 16 captive chimpanzees at the Wolfgang Kohler Primate Research Center in Germany (Leipzig) and 12 semi-wild chimpanzees at the Chimfunshi Wildlife Orphanage Trust, a sanctuary that houses more than a hundred chimpanzees under nearly natural conditions in the north-western part of Zambia. Chimpanzees were trained on two different vending machines. A minority of the group was made familiar with one machine and the majority of group members with the other machine. Wooden balls were thrown into their enclosure; the chimpanzees could insert these balls into the machines to receive one peanut for each ball.

Van Leeuwen and his colleagues first aimed to replicate previous research and looked whether the chimpanzees in the minority group would change their behaviour toward using the vending machine that the majority of group members used. However, neither the German nor the Zambian chimpanzees gave up their strategy to join the majority. In the second study, the profitability of the vending machines was changed so that the vending machine that the minority used became more profitable, now spitting out five rewards for every ball inserted. Over time, the majority chimpanzees observed that the minority chimpanzees received more peanuts for the same effort and all but one gradually switched to using this more profitable machine.

Higher rewards

“Where chimpanzees do not readily change their behaviour under majority influences, they do change their behaviour when they can maximise their payoffs,” Van Leeuwen says. “We conclude that chimpanzees may prefer persevering in successful and familiar strategies over adopting the equally effective strategy of the majority, but that chimpanzees find sufficient incentive in changing their behaviour when they can obtain higher rewards somewhere else.” “So, it’s peanuts over popularity” he jokingly adds.

The researchers emphasise that these results may be dependent upon the specific trade-offs that were created by the experimental design and that chimpanzees could act differently under the pressures of life in the wild. Van Leeuwen: “Conformity could still be a process guiding chimpanzees’ behaviour. Chimpanzee females, for instance, disperse to other groups in the wild. For these females, it is of vital importance to integrate into the new group. Conformity to local (foraging) customs might help them to achieve this integration.”

Journal Reference:

  1. Edwin J. C. Van Leeuwen, Katherine A. Cronin, Sebastian Schütte, Josep Call, Daniel B. M. Haun. Chimpanzees (Pan troglodytes) Flexibly Adjust Their Behaviour in Order to Maximize Payoffs, Not to Conform to MajoritiesPLoS ONE, 2013; 8 (11): e80945 DOI:10.1371/journal.pone.0080945

Transgendered Males Seen as an Asset to Some Ancestral Societies (Science Daily)

Oct. 2, 2013 — Transgendered androphilic males were accepted in traditional hunter-gatherer cultures because they were an extra set of hands to support their families. Conversely, by investing in and supporting their kin, these males ensured that their familial line — and therefore also their own genetic make-up — passed on to future generations despite their not having children of their own. This is according to an ethnographic study led by Doug VanderLaan of the Centre for Addiction and Mental Health in Canada, published in Springer’s journal Human Nature. The study reports that this “kin selection” is still at play in pro-transgender societies today.

‘Androphilia’ refers to a predominant sexual attraction towards adult males, and takes on one of two possible gender roles depending on the cultural context: sex-gender congruent male androphilia (the typical male gender role) or transgendered androphilia (a gender role markedly similar to that of females in a given culture). Typically one of these variations is dominant within a society. For example, sex-gender congruency is more common in Western cultures, whereas the transgendered form is more typical of non-Western cultures, such as that of the Polynesian island nation of Samoa. The researchers also wanted to test predictions that enhanced kin-directed altruism is prominent in societies in which transgendered male androphilia is predominant.

To answer this question, VanderLaan and his colleagues compared the sociocultural environment of contemporary transgendered societies with ancestral small-group hunter-gatherers. Ancestral group size, sociopolitical systems, religious beliefs and patterns of residency were analyzed in 146 non-transgendered societies, and 46 transgender societies.

The analysis utilized ethnographic information about well-described nonindustrial societies from the Standard Cross-Cultural Sample.VanderLaan and his colleagues found that transgendered male androphilia is an ancestral phenomenon typically found in communities with certain ancestral sociocultural conditions, such as “bilateral descent.” This term refers to societies in which the families of both one’s father and mother are equally important for emotional, social, spiritual and political support, as well as the transfer of property or wealth.

Also, the acceptance and tolerance of same-sex behavior evolved within a suitable, accepting environment in which discrimination against transgendered males was rare. Importantly, kin selection might have played a vital part in maintaining genes for male androphilia these societies. For example, it continues to be a driving force in contemporary Samoan fa’afafine transgender communities.Unless transgendered androphilic males are accepted by their families, the opportunities for them to invest in kin are likely limited. What was true of our ancestors still holds true. A society’s specific social organization and its general acceptance of transgenderism and homosexuality is even important today. When supported by society, transgendered males invest their time and energy in their kin in turn.

Journal Reference:

  1. Doug P. VanderLaan, Zhiyuan Ren, Paul L. Vasey. Male Androphilia in the Ancestral EnvironmentHuman Nature, 2013; DOI: 10.1007/s12110-013-9182-z

Notas sobre a violência – De antropólogos e outras tribos ferozes (Folha de S.Paulo)



RESUMO Antropólogo Napoleon Chagnon retoma em novo livro teoria sobre agressividade ianomâmi e ataca adversários da sociobiologia. Jared Diamond escreve obra de bases semelhantes, mas mais generosa com ‘primitivos’, aproximando-se de adversários de Chagnon, como Manuela Carneiro da Cunha, que lança coletânea.

É preciso ter estômago forte para digerir a narrativa de um antropólogo que escolhe iniciar o relato de seu primeiro dia de campo entre os ianomâmis -meio século depois- com a frase: “Nunca antes tinha visto tanto ranho verde”. Não é a antropologia, porém, a disciplina que ensina a combinar o máximo de disciplina com o mínimo de conforto em benefício do entendimento do homem?

Leia-se então com dose generosa de bonomia antropológica a obra mais recente do americano Napoleon Chagnon, “Noble Savages – My Life among two Dangerous Tribes – The Yanomamö and the Anthropologists” [Simon & Schuster, 531 págs., R$ 87,50]. Em desagravo, que seja, porque Chagnon pagou um preço alto demais por sua crença nas explicações ultradarwinistas do comportamento, cuja matriz -a natureza humana- acredita ter desvendado nas selvas do Orinoco.

O estudioso americano dedicou pelo menos duas décadas de sua vida a longas permanências em terras ianomâmis, quase sempre na Venezuela (com desastradas incursões também do lado brasileiro). As três seguintes ele ocupou em defesa da carreira e da reputação quase arruinadas por dois outros livros: “O Povo Feroz” (1968), trabalho acadêmico de sua própria lavra, e “Trevas no Eldorado”, um panfleto do jornalista Patrick Tierney (2000).

Os que desconhecem a crônica dessa guerra entre os clãs cultural e biológico da antropologia encontrarão um resumo devastador das acusações mútuas no documentário “Os Segredos da Tribo”, de José Padilha. Não se recomenda o consumo de pipoca na sessão de barbaridades que a fita apresenta.

O povo feroz do título de Chagnon são os ianomâmis. Sua caracterização pelo antropólogo como uma etnia violenta, de homens “maliciosos, agressivos e intimidadores”, que acumulam homicídios para obter mais mulheres e maior sucesso reprodutivo, despertou a ira dos antropólogos culturalistas.

Primeiro, Chagnon foi acusado de distorcer a imagem do grupo e, assim, facilitar sua dizimação por brancos dos dois lados da fronteira. Depois, foi denunciado por Tierney como genocida, pois teria -intencional ou negligentemente, sob a tutela do médico americano James V. Neel- contribuído para uma epidemia de sarampo que matou centenas de índios.

BOM SELVAGEM “Noble Savages” (“bons selvagens”) é um acerto de contas com as duas tribos que infernizaram sua vida. A partir da descrição para o público não especializado de seu convívio de cinco anos com os ianomâmis, Chagnon retoma sua conclusão de que o “bom selvagem” concebido por Rousseau é um mito politicamente correto e que só há uma resposta biológica (evolucionista) -e simploriamente hobbesiana- para a questão de por que seres humanos são sociais: a luta de todos contra todos para aumentar a própria prole (ou pôr mais cópias dos próprios genes no mundo, na vulgata sociobiológica).

Não faltam páginas desairosas para os ianomâmis no livro. “Olhei para cima e arfei, em choque, quando vi uma dúzia de homens corpulentos, nus, suados e pavorosos nos encarando por trás dos caniços de suas setas apontadas!” -conta sobre a primeira visita a uma casa coletiva dos índios.

“Imensos rolos de tabaco verde estavam enfiados entre os dentes e os lábios inferiores, tornando sua aparência ainda mais pavorosa. Veios de ranho verde escuro pingavam ou pendiam de suas narinas -tão longos que se desprendiam de seus queixos, caíam sobre os músculos peitorais e escorriam preguiçosamente sobre seus ventres, mesclando-se com a pintura vermelha e o suor.”

Chagnon também não economiza relatos sobre tentativas mal sucedidas de engodo dos ianomâmis contra ele. Sempre eficazes, por outro lado, eram seus próprios ardis para levá-los a ceder amostras de sangue (para Neel) e a revelar nomes de ancestrais mortos -um tabu- para rechear suas genealogias e estatísticas. As mesmas informações, pagas com machados, facas e panelas de metal, que lhe permitiriam afirmar, depois, serem os homens com mais homicídios nas costas também os de prole mais numerosa.

Muito antes das acusações de Tierney, as conclusões sociobiológicas e os métodos traficantes de Chagnon já vinham sendo questionados por seus pares na comunidade antropológica. Até a correlação estatística entre ferocidade e fertilidade masculina, formulada num famigerado artigo de 1988 para a revista acadêmica “Science”, teve seus dados postos em dúvida (o autor foi acusado de excluir da amostra aqueles pais que já haviam sido mortos por vingança, portanto sem meios de multiplicar descendência).

Os antropólogos culturais, refratários à moldura biológica em que Chagnon queria enquadrar o painel exuberante das culturas, já estavam no seu encalço. Nada se compara, porém, com a virulência do ataque de Tierney. Assim que um capítulo do livro foi publicado na revista “New Yorker”, em outubro de 2000, a Associação Antropológica Americana entrou na briga -do lado dos culturalistas. Foi montado um comitê de investigação, que acabou por inocentar o médico Neel e descartar a epidemia intencional, mas recriminou Chagnon por desvios éticos.

O caso teve enorme repercussão na imprensa mundial, brasileira inclusive. Contudo, quando a obra do “jornalista investigativo” Tierney e os próprios investigadores da AAA passaram a ser investigados, a começar pela historiadora da ciência Susan Lindee, o vento virou.

Forçada por um referendo entre seus membros, a associação renegaria o relatório. As acusações de Tierney não paravam de pé, como reconstitui com farta documentação um ensaio demolidor da também historiadora Alice Dreger publicado em 2011 no periódico acadêmico “Human Nature”, sob o título “Darkness’s descent on the American Anthropological Association. A cautionary tale” (trevas sobre a Associação Antropológica Americana – uma fábula moral; leia em

Dreger puxa vários fios da teia de perseguição a Chagnon. Levanta a suspeita, intrigante, de que a cruzada de Tierney pode ter ocorrido sob o patrocínio da Igreja Católica, mais especificamente da ordem de padres salesianos, que já mantinha missões junto aos ianomâmis da Venezuela quando o antropólogo por lá baixou.

Após alguns meses de convívio e cooperação, cientista e religiosos se estranharam. Na versão fantástica narrada em “Noble Savages”, isso ocorreu depois de um hierarca pedir a Chagnon ajuda para matar um padre amasiado com índia. Na passagem do livro que mais se avizinha do estilo de Tierney, o antropólogo também acusa os salesianos de distribuir espingardas cartucheiras entre os índios para conquistar seu favor.

A inconsistência mais relevante da obra, porém, não decorre do ânimo retaliatório, e sim da pretensão de ter localizado entre os ianomâmis as nascentes da agressividade que supõe inerente à natureza humana. A antropóloga Elizabeth Povinelli assinalou, numa resenha escaldante de “Noble Savages” para o “New York Times”, que a tese se assenta sobre a premissa falaciosa de que os ianomâmis sejam relíquias de uma infância neolítica da humanidade.

FÓSSEIS Desde esse ponto de vista, compreende-se melhor o esforço retórico de Chagnon em degradar os ianomâmis, acentuando nas suas descrições uma animalidade que serve para relocar sua cultura na vizinhança da biologia. Ora, não há básica empírica nenhuma para afirmar que sociedades “primitivas” como a dos ianomâmis se mantiveram à margem da história, fósseis de um passado inaugural da espécie humana.

Como lembra Manuela Carneiro da Cunha -que presidia a Associação Brasileira de Antropologia quando esta cerrou fileiras contra Chagnon- na coletânea de ensaios “Índios no Brasil – História, Direitos e Cidadania” [Claro Enigma, 160 págs., R$ 29,50], essa é uma visão originária do século 19, que atribui “à natureza e à fatalidade de suas leis o que é produto de política e práticas humanas, […] consoladoras para todos à exceção de suas vítimas”.

Os ianomâmis, por exemplo, só permaneceram mais ou menos isolados (na realidade, longas redes de contatos já lhes garantiam acesso a artefatos de metal) porque suas terras montanhosas não interessavam a colonizador algum.

A perspectiva adotada por Chagnon -um engenheiro convertido para a antropologia- faz tábula rasa de tudo que há de peculiar no modo de vida ianomâmi. Por que cargas d’água esses índios cremam seus mortos, moem os ossos calcinados e ingerem as cinzas com um mingau de banana? É esse tipo de manifestação simbólica que a antropologia cultural se esforça por sistematizar e elucidar, mas que a obra de Chagnon relega à penumbra dos detalhes irrelevantes para a “natureza humana”.

Ótica semelhante anima o último best-seller de outro adepto declarado da sociobiologia (rebatizada psicologia evolucionista), Jared Diamond, mas com resultados muito diversos, se não opostos. Em “The World until Yesterday – What Can We Learn from Traditional Societies?” [Viking, 512 págs., R$ 96,90], Diamond acredita piamente ter aberto uma janela para o passado nas suas décadas de visitas à Nova Guiné para estudar pássaros.

A ilha, fervilhante com centenas de tribos e línguas em contato e conflito, constitui um continente cultural descoberto como tal por ocidentais só nas primeiras décadas do século 20. Fornece a Diamond, portanto, o equivalente dos ianomâmis para Chagnon, em matéria de isolamento e primitivismo.

As diferenças entre esses dois generalizadores prodigiosos, contudo, salta já do título de Diamond. Ao contrário de Chagnon, ele está aberto -mais que isso, interessado- a aprender algo com os nativos, e não só sobre eles. São muitas as lições úteis que o observador de pássaros e homens extrai para o aperfeiçoamento marginal do indubitavelmente superior modo de vida ocidental: ingerir menos sal, aleitar bebês à vontade até os três anos, dar educação bilíngue às crianças, fazer refeições lentamente com amigos…

Até das ameaças constantes da natureza e do estado de guerra crônica entre os primitivos Diamond retira um ensinamento, centro de gravidade do livro, que chama de “paranoia construtiva”: o estado de vigilância permanente para os muitos perigos que a vida oferece aos homens. Depois de embasbacar multidões com as generalizações audazes de “Armas, Germes e Aço” (livro pelo qual ganhou o Pulitzer em 1998), Diamond corteja com leveza o gênero da autoajuda e compila um volume de leitura bem mais amena que

“Noble Savages”. Os ilhéus são feios e sujos como os ianomâmis, mas simpáticos e sábios.

Já a paranoia de Chagnon, se cabe falar assim, é corrosiva. Nos termos da controvérsia que animou o Brasil escravizador de índios nos séculos 18 e 19, relatada por Manuela Carneiro da Cunha, eles podem ser encarados como cães, canibais e ferozes, ou como homens, diferentes e por isso exemplares de capacidade adaptativa e perfectibilidade. É uma questão de escolha, ou de ponto de vista.

Como diz a antropóloga, repetindo o que ouviu em conferência de Claude Lévi-Strauss, a sociodiversidade pode ser tão preciosa quanto a biodiversidade: “Creio, com efeito, que ela constitui essa reserva de achados na qual as futuras gerações poderão encontrar exemplos -e quem sabe novos pontos de partida- de processos e sínteses sociais já postos à prova”.


Em 2012, Napoleon Chagnon foi eleito para a prestigiada Academia Nacional de Ciências (NAS) dos Estados Unidos. Ato contínuo, em protesto, o antropólogo Marshall Sahlins -que em 2000 se engajara na campanha contra ele- renunciou à sua cadeira na NAS.

Manifesto de 17 antropólogos que trabalham com ianomâmis deblaterou mais uma vez contra a noção de “povo feroz” reiterada no novo livro, que poderia ser usada por governos para prejudicar a etnia. Uma nota do líder ianomâmi David Kopenawa sobre a obra aponta as guerras dos brancos como muito mais ferozes que as de seu povo -uma observação antropologicamente perspicaz, ao menos no que respeita às tribos dos culturalistas e dos sociobiólogos.

Edward O. Wilson: The Riddle of the Human Species (N.Y.Times)

THE STONEFebruary 24, 2013, 7:30 pm


The task of understanding humanity is too important and too daunting to leave to the humanities. Their many branches, from philosophy to law to history and the creative arts, have described the particularities of human nature with genius and exquisite detail, back and forth in endless permutations. But they have not explained why we possess our special nature and not some other out of a vast number of conceivable possibilities. In that sense, the humanities have not accounted for a full understanding of our species’ existence.

So, just what are we? The key to the great riddle lies in the circumstance and process that created our species. The human condition is a product of history, not just the six millenniums of civilization but very much further back, across hundreds of millenniums. The whole of it, biological and cultural evolution, in seamless unity, must be explored for an answer to the mystery. When thus viewed across its entire traverse, the history of humanity also becomes the key to learning how and why our species survived.

A majority of people prefer to interpret history as the unfolding of a supernatural design, to whose author we owe obedience. But that comforting interpretation has grown less supportable as knowledge of the real world has expanded. Scientific knowledge (measured by numbers of scientists and scientific journals) in particular has been doubling every 10 to 20 years for over a century. In traditional explanations of the past, religious creation stories have been blended with the humanities to attribute meaning to our species’s existence. It is time to consider what science might give to the humanities and the humanities to science in a common search for a more solidly grounded answer to the great riddle.

To begin, biologists have found that the biological origin of advanced social behavior in humans was similar to that occurring elsewhere in the animal kingdom. Using comparative studies of thousands of animal species, from insects to mammals, they have concluded that the most complex societies have arisen through eusociality — roughly, “true” social condition. The members of a eusocial group cooperatively rear the young across multiple generations. They also divide labor through the surrender by some members of at least some of their personal reproduction in a way that increases the “reproductive success” (lifetime reproduction) of other members.

Leif Parsons

Eusociality stands out as an oddity in a couple of ways. One is its extreme rarity. Out of hundreds of thousands of evolving lines of animals on the land during the past 400 million years, the condition, so far as we can determine, has arisen only about two dozen times. This is likely to be an underestimate, due to sampling error. Nevertheless, we can be certain that the number of originations was very small.

Furthermore, the known eusocial species arose very late in the history of life. It appears to have occurred not at all during the great Paleozoic diversification of insects, 350 to 250 million years before the present, during which the variety of insects approached that of today. Nor is there as yet any evidence of eusocial species during the Mesozoic Era until the appearance of the earliest termites and ants between 200 and 150 million years ago. Humans at the Homo level appeared only very recently, following tens of millions of years of evolution among the primates.

Once attained, advanced social behavior at the eusocial grade has proved a major ecological success. Of the two dozen independent lines, just two within the insects — ants and termites — globally dominate invertebrates on the land. Although they are represented by fewer than 20 thousand of the million known living insect species, ants and termites compose more than half of the world’s insect body weight.

The history of eusociality raises a question: given the enormous advantage it confers, why was this advanced form of social behavior so rare and long delayed? The answer appears to be the special sequence of preliminary evolutionary changes that must occur before the final step to eusociality can be taken. In all of the eusocial species analyzed to date, the final step before eusociality is the construction of a protected nest, from which foraging trips begin and within which the young are raised to maturity. The original nest builders can be a lone female, a mated pair, or a small and weakly organized group. When this final preliminary step is attained, all that is needed to create a eusocial colony is for the parents and offspring to stay at the nest and cooperate in raising additional generations of young. Such primitive assemblages then divide easily into risk-prone foragers and risk-averse parents and nurses.

Leif Parsons

What brought one primate line to the rare level of eusociality? Paleontologists have found that the circumstances were humble. In Africa about two million years ago, one species of the primarily vegetarian australopithecine evidently shifted its diet to include a much higher reliance on meat. For a group to harvest such a high-energy, widely dispersed source of food, it did not pay to roam about as a loosely organized pack of adults and young like present-day chimpanzees and bonobos. It was more efficient to occupy a campsite (thus, the nest) and send out hunters who could bring home meat, either killed or scavenged, to share with others. In exchange, the hunters received protection of the campsite and their own young offspring kept there.

From studies of modern humans, including hunter-gatherers, whose lives tell us so much about human origins, social psychologists have deduced the mental growth that began with hunting and campsites. A premium was placed on personal relationships geared to both competition and cooperation among the members. The process was ceaselessly dynamic and demanding. It far exceeded in intensity anything similar experienced by the roaming, loosely organized bands of most animal societies. It required a memory good enough to assess the intentions of fellow members, to predict their responses, from one moment to the next; and it resulted in the ability to invent and inwardly rehearse competing scenarios of future interactions.

The social intelligence of the campsite-anchored prehumans evolved as a kind of non-stop game of chess. Today, at the terminus of this evolutionary process, our immense memory banks are smoothly activated across the past, present, and future. They allow us to evaluate the prospects and consequences variously of alliances, bonding, sexual contact, rivalries, domination, deception, loyalty and betrayal. We instinctively delight in the telling of countless stories about others as players upon the inner stage. The best of it is expressed in the creative arts, political theory, and other higher-level activities we have come to call the humanities.

The definitive part of the long creation story evidently began with the primitive Homo habilis (or a species closely related to it) two million years ago. Prior to the habilines the prehumans had been animals. Largely vegetarians, they had human-like bodies, but their cranial capacity remained chimpanzee-size, at or below 500 cubic centimeters. Starting with the habiline period the capacity grew precipitously: to 680 cubic centimeters in Homo habilis, 900 in Homo erectus, and about 1,400 in Homo sapiens. The expansion of the human brain was one of the most rapid episodes of evolution of complex organs in the history of life.

Still, to recognize the rare coming together of cooperating primates is not enough to account for the full potential of modern humans that brain capacity provides. Evolutionary biologists have searched for the grandmaster of advanced social evolution, the combination of forces and environmental circumstances that bestowed greater longevity and more successful reproduction on the possession of high social intelligence. At present there are two competing theories of the principal force. The first is kin selection: individuals favor collateral kin (relatives other than offspring) making it easier for altruism to evolve among members of the same group. Altruism in turn engenders complex social organization, and, in the one case that involves big mammals, human-level intelligence.

The second, more recently argued theory (full disclosure: I am one of the modern version’s authors), the grandmaster is multilevel selection. This formulation recognizes two levels at which natural selection operates: individual selection based on competition and cooperation among members of the same group, and group selection, which arises from competition and cooperation between groups. Multilevel selection is gaining in favor among evolutionary biologists because of a recent mathematical proof that kin selection can arise only under special conditions that demonstrably do not exist, and the better fit of multilevel selection to all of the two dozen known animal cases of eusocial evolution.

The roles of both individual and group selection are indelibly stamped (to borrow a phrase from Charles Darwin) upon our social behavior. As expected, we are intensely interested in the minutiae of behavior of those around us. Gossip is a prevailing subject of conversation, everywhere from hunter-gatherer campsites to royal courts. The mind is a kaleidoscopically shifting map of others, each of whom is drawn emotionally in shades of trust, love, hatred, suspicion, admiration, envy and sociability. We are compulsively driven to create and belong to groups, variously nested, overlapping or separate, and large or small. Almost all groups compete with those of similar kind in some manner or other. We tend to think of our own as superior, and we find our identity within them.

The existence of competition and conflict, the latter often violent, has been a hallmark of societies as far back as archaeological evidence is able to offer. These and other traits we call human nature are so deeply resident in our emotions and habits of thought as to seem just part of some greater nature, like the air we all breathe, and the molecular machinery that drives all of life. But they are not. Instead, they are among the idiosyncratic hereditary traits that define our species.

The major features of the biological origins of our species are coming into focus, and with this clarification the potential of a more fruitful contact between science and the humanities. The convergence between these two great branches of learning will matter hugely when enough people have thought it through. On the science side, genetics, the brain sciences, evolutionary biology, and paleontology will be seen in a different light. Students will be taught prehistory as well as conventional history, the whole presented as the living world’s greatest epic.

We will also, I believe, take a more serious look at our place in nature. Exalted we are indeed, risen to be the mind of the biosphere without a doubt, our spirits capable of awe and ever more breathtaking leaps of imagination. But we are still part of earth’s fauna and flora. We are bound to it by emotion, physiology, and not least, deep history. It is dangerous to think of this planet as a way station to a better world, or continue to convert it into a literal, human-engineered spaceship. Contrary to general opinion, demons and gods do not vie for our allegiance. We are self-made, independent, alone and fragile. Self-understanding is what counts for long-term survival, both for individuals and for the species.

Edward O. Wilson is Honorary Curator in Entomology and University Research Professor Emeritus, Harvard University. He has received more than 100 awards for his research and writing, including the U. S. National Medal of Science, the Crafoord Prize and two Pulitzer Prizes in non-fiction. His most recent book is “The Social Conquest of Earth.”

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Interview with Edward O. Wilson: The Origin of Morals (Spiegel)

February 26, 2013 – 01:23 PM

By Philip Bethge and Johann Grolle

American sociobiologist Edward O. Wilson is championing a controversial new approach for explaining the origins of virtue and sin. In an interview, the world-famous ant reseacher explains why he believes the inner struggle is the characteristic trait of human nature.

Edward O. Wilson doesn’t come across as the kind of man who’s looking to pick a fight. With his shoulders upright and his head tilting slightly to the side, he shuffles through the halls of Harvard University. His right eye, which has given him trouble since his childhood, is halfway closed. The other is fixed on the ground. As an ant researcher, Wilson has made a career out of things that live on the earth’s surface.

There’s also much more to Wilson. Some consider him to be the world’s most important living biologist, with some placing him on a level with Charles Darwin.

In addition to discovering and describing hundreds of species of ants, Wilson’s book on this incomparably successful group of insects is the only non-fiction biology tome ever to win a Pulitzer Prize. Another achievement was decoding the chemical communication of ants, whose vocabulary is composed of pheromones. His study of the ant colonization of islands helped to establish one of the most fruitful branches of ecology. And when it comes to the battle against the loss of biodiversity, Wilson is one of the movement’s most eloquent voices.

‘Blessed with Brilliant Enemies’

But Wilson’s fame isn’t solely the product of his scientific achievements. His enemies have also helped him to establish a name. “I have been blessed with brilliant enemies,” he says. In fact, the multitude of scholars with whom Wilson has skirmished academically is illustrious. James Watson, one of the discoverers of the double helix in DNA is among them, as is essayist Stephen Jay Gould.

At 83 years of age, Wilson is still at work making a few new enemies. The latest source of uproar is a book, “The Social Conquest of Earth,” published last April in the United States and this month in a German-language edition. In the tome, Wilson attempts to describe the triumphal advance of humans in evolutionary terms.

It is not uncommon for Wilson to look to ants for inspiration in his writings — and that proves true here, as well. When, for example, he recalls beholding two 90-million-year-old worker ants that were trapped in a piece of fossil metasequoia amber as being “among the most exciting moments in my life,” a discovery that “ranked in scientific importance withArchaeopteryx, the first fossil intermediary between birds and dinosaurs, and Australopithecus, the first ‘missing link’ discovered between modern humans and the ancestral apes.”

But that’s all just foreplay to the real controversy at the book’s core. Ultimately, Wilson uses ants to explain humans’ social behavior and, by doing so, breaks with current convention. The key question is the level at which Darwinian selection of human characteristics takes place. Did individuals enter into a fight for survival against each other, or did groups battle it out against competing groups?

Prior to this book, Wilson had been an influential champion of the theory of kin selection. He has now rejected his previous teachings, literally demolishing them. “The beautiful theory never worked well anyway, and now it has collapsed,” he writes. Today, he argues that human nature can only be understood if it is perceived as being the product of “group selection” — a view that Wilson’s fellow academics equate with sacrilege. They literally lined up to express their scientific dissent in a joint letter.

Some of the most vociferous criticism has come from Richard Dawkins, whose bestselling 1976 book “The Selfish Gene” first introduced the theory of kin selection to a mass audience. In a withering review of Wilson’s book in Britain’s Prospect magazine, Dawkins accuses a man he describes as his “lifelong hero” of “wanton arrogance” and “perverse misunderstandings”. “To borrow from Dorothy Parker,” he writes, “this is not a book to be tossed lightly aside. It should be thrown with great force.”

SPIEGEL recently sat down with sociobiologist Wilson to discuss his book and the controversy surrounding it.

SPIEGEL: Professor Wilson, lets assume that 10 million years ago some alien spacecraft had landed on this planet. Which organisms would they find particularly intriguing?

Wilson: Their interest, I believe, would not have been our ancestors. Primarily, they would have focused on ants, bees, wasps, and termites. Their discovery is what the aliens would report back to headquarters.

SPIEGEL: And you think those insects would be more interesting to them than, for example, elephants, flocks of birds or intelligent primates?

Wilson: They would be, because, at that time, ants and termites would be the most abundant creatures on the land and the most highly social creatures with very advanced division of labor and caste. We call them “eusocial,” and this phenomenon seems to be extremely rare.

SPIEGEL: What else might the aliens consider particularly interesting about ants?

Wilson: Ants engage in farming and animal husbandry. For example, some of them cultivate fungi. Others herd aphids and literally milk them by stroking them with their antennae. And the other thing the aliens would find extremely interesting would be the degree to which these insects organize their societies by pheromones, by chemical communication. Ants and termites have taken this form of communication to extremes.

SPIEGEL: So the aliens would cable back home: “We have found ants. They are the most promising candidates for a future evolution towards intelligent beings on earth?”

Wilson: No, they wouldn’t. They would see that these creatures were encased in exoskeletons and therefore had to remain very small. They would conclude that there was little chance for individual ants or termites to develop much reasoning power, nor, as a result, the capacity for culture. But at least on this planet, you have to be big in order to have sufficient cerebral cortex. And you probably have to be bipedal and develop hands with pulpy fingers, because those give you the capacity to start creating objects and to manipulate the environment.

SPIEGEL: Would our ancestors not have caught their eye?

Wilson: Ten million years ago, our ancestors indeed had developed a somewhat larger brain and versatile hands already. But the crucial step had yet to come.

SPIEGEL: What do you mean?

Wilson: Let me go back to the social insects for a moment. Why did social insects start to form colonies? Across hundreds of millions of years, insects had been proliferating as solitary forms. Some of them stayed with their young for a while, guided them and protected them. You find that widespread but far from universal in the animal kingdom. However, out of those species came a much smaller number of species who didn’t just protect their young, but started building nests that they defended …

SPIEGEL: … similar to birds.

Wilson: Yes. And I think that birds are right at the threshold of eusocial behaviour. But looking at the evolution of ants and termites again, there is another crucial step. In an even smaller group, the young don’t only grow up in their nest, but they also stay and care for the next generation. Now you have a group staying together with a division of labor. That is evidently the narrow channel of evolution that you have to pass through in order to become eusocial.

SPIEGEL: And our ancestors followed the same path?

Wilson: Yes. I argue that Homo habilis, the first humans, also went through these stages. In particular, Homo habilis was unique in that they already had shifted to eating meat.

SPIEGEL: What difference would that make?

Wilson: When animals start eating meat, they tend to form packs and to divide labor. We know that the immediate descendants of Homo habilis, Homo erectus, gathered around camp sites and that they actually had begun to use fire. These camp sites are equivalent to nests. That’s where they gathered in a tightly knit group, and then individuals went out searching for food.

SPIEGEL: And this development of groups drives evolution even further?

Wilson: Exactly. And, for example, if it now comes to staking out the hunting grounds, then group stands against group.

SPIEGEL: Meaning that this is the origin of warfare?

Wilson: Yes. But it doesn’t take necessarily the forming of an army or a battalion and meeting on the field and fighting. It was mostly what you call “vengeance raids”. One group attacks another, maybe captures a female or kills one or two males. The other group then counterraids, and this will go back and forth, group against group.

SPIEGEL: You say that this so called group selection is vital for the evolution of humans. Yet traditionally, scientists explain the emergence of social behavior in humans by kin selection.

Wilson: That, for a number of reasons, isn’t much good as an explanation.

SPIEGEL: But you yourself have long been a proponent of this theory. Why did you change your mind?

Wilson: You are right. During the 1970s, I was one of the main proponents of kin selection theory. And at first the idea sounds very reasonable. So for example, if I favored you because you were my brother and therefore we share one half of our genes, then I could sacrifice a lot for you. I could give up my chance to have children in order to get you through college and have a big family. The problem is: If you think it through, kin selection doesn’t explain anything. Instead, I came to the conclusion that selection operates on multiple levels. On one hand, you have normal Darwinian selection going on all the time, where individuals compete with each other. In addition, however, these individuals now form groups. They are staying together, and consequently it is group versus group.

SPIEGEL: Turning away from kin selection provoked a rather fierce reaction from many of your colleagues.

Wilson: No, it didn’t. The reaction was strong, but it came from a relatively small group of people whose careers are based upon studies of kin selection.

SPIEGEL: Isn’t that too easy? After all, 137 scientists signed a response to your claims. They accuse you of a “misunderstanding of evolutionary theory”.

Wilson: You know, most scientists are tribalists. Their lives are so tied up in certain theories that they can’t let go.

SPIEGEL: Does it even make a substantial difference if humans evolved through kin selection or group selection?

Wilson: Oh, it changes everything. Only the understanding of evolution offers a chance to get a real understanding of the human species. We are determined by the interplay between individual and group selection where individual selection is responsible for much of what we call sin, while group selection is responsible for the greater part of virtue. We’re all in constant conflict between self-sacrifice for the group on the one hand and egoism and selfishness on the other. I go so far as to say that all the subjects of humanities, from law to the creative arts are based upon this play of individual versus group selection.

SPIEGEL: Is this Janus-faced nature of humans our greatest strength at the end of the day?

Wilson: Exactly. This inner conflict between altruism and selfishness is the human condition. And it is very creative and probably the source of our striving, our inventiveness and imagination. It’s that eternal conflict that makes us unique.

SPIEGEL: So how do we negotiate this conflict?

Wilson: We don’t. We have to live with it.

SPIEGEL: Which element of this human condition is stronger?

Wilson: Let’s put it this way: If we would be mainly influenced by group selection, we would be living in kind of an ant society.

SPIEGEL: … the ultimate form of communism?

Wilson: Yes. Once in a while, humans form societies that emphasize the group, for example societies with Marxist ideology. But the opposite is also true. In other societies the individual is everything. Politically, that would be the Republican far right.

SPIEGEL: What determines which ideology is predominant in a society?

Wilson: If your territory is invaded, then cooperation within the group will be extreme. That’s a human instinct. If you are in a frontier area, however, then we tend to move towards the extreme individual level. That seems to be a good part of the problem still with America. We still think we’re on the frontier, so we constantly try to put forward individual initiative and individual rights and rewards based upon individual achievement.

SPIEGEL: Earlier, you differentiated between the “virtue” of altruism and the “sin” of individualism. In your book you talk about the “poorer and the better angels” of human nature. Is it helpful to use this kind of terminology?

Wilson: I will admit that using the terminology of “virtue” and “sin” is what poets call a “trope”. That is to say, I wanted the idea in crude form to take hold. Still, a lot of what we call “virtue” has to do with propensities to behave well toward others. What we call “sin” are things that people do mainly out of self-interest.

SPIEGEL: However, our virtues towards others go only so far. Outside groups are mainly greeted with hostility.

Wilson: You are right. People have to belong to a group. That’s one of the strongest propensities in the human psyche and you won’t be able to change that. However, I think we are evolving, so as to avoid war — but without giving up the joy of competition between groups. Take soccer …

SPIEGEL: … or American football.

Wilson: Oh, yes, American football, it’s a blood sport. And people live by team sports and national or regional pride connected with team sports. And that’s what we should be aiming for, because, again, that spirit is one of the most creative. It landed us on the moon, and people get so much pleasure from it. I don’t want to see any of that disturbed. That is a part of being human. We need our big games, our team sports, our competition, our Olympics.

SPIEGEL: “Humans,” the saying goes, “have Paleolithic emotions” …

Wilson: … “Medieval institutions and god-like technology”. That’s our situation, yeah. And we really have to handle that.


Wilson: So often it happens that we don’t know how, also in situations of public policy and governance, because we don’t have enough understanding of human nature. We simply haven’t looked at human nature in the best way that science might provide. I think what we need is a new Enlightenment. During the 18th century, when the original Enlightenment took place, science wasn’t up to the job. But I think science is now up to the job. We need to be harnessing our scientific knowledge now to get a better, science-based self-understanding.

SPIEGEL: It seems that, in this process, you would like to throw religions overboard altogether?

Wilson: No. That’s a misunderstanding. I don’t want to see the Catholic Church with all of its magnificent art and rituals and music disappear. I just want to have them give up their creation stories, including especially the resurrection of Christ.

SPIEGEL: That might well be a futile endeavour …

Wilson: There was this American physiologist who was asked if Mary’s bodily ascent from Earth to Heaven was possible. He said, “I wasn’t there; therefore, I’m not positive that it happened or didn’t happen; but of one thing I’m certain: She passed out at 10,000 meters.” That’s where science comes in. Seriously, I think we’re better off with no creation stories.

SPIEGEL: With this new Enlightenment, will we reach a higher state of humanity?

Wilson: Do we really want to improve ourselves? Humans are a very young species, in geologic terms, and that’s probably why we’re such a mess. We’re still living with all this aggression and ability to go to war. But do we really want to change ourselves? We’re right on the edge of an era of being able to actually alter the human genome. But do we want that? Do we want to create a race that’s more rational and free of many of these emotions? My response is no, because the only thing that distinguishes us from super-intelligent robots are our imperfect, sloppy, maybe even dangerous emotions. They are what makes us human.

SPIEGEL: Mr. Wilson, we thank you for this conversation.

Interview conducted by Philip Bethge and Johann Grolle