Wade, N. A troublesome inheritance.

Genes, Race and Human History.
2014, New York: Pinguin Books.

Y a-t-il des vérités qu’il ne faut pas dire? En tous cas parler de races est très difficile dans notre société. Le livre de Wade aborde la question sans détour. Il présente les faits et il élabores des hypothèses sur leurs vraisemblables conséquences. La lecture est passionnante et donne ample matière à penser. Elle est dérangeante parce que, de race à racisme, le pas est vite franchi. Il ne l’est pas dans ce livre mais le chapitre qui éclairerait ce danger manque sombrement.

Le livre est sur le web: https://atroublesomeinheritance.files.wordpress.com/2014/09/nicholas-wade-a-troublesome-inheritance_-genes-race-and-human-history-penguin-press-hc-the-20141.pdf

Inutile d’en refaire la recension du livre de Wade, celle de C. Murray (ci-dessous) est excellente. J’en recommande la lecture. Il faut toutefois savoir que ce monsieur est de la droite nationaliste américaine et qu’il travaille pour un think tank néolibéral pur et dur. Il a écrit dans les conclusions du livre dont il est coauteur, The Bell Curve, « … the main purpose of immigration law should be to serve America’s interests ». C’est clair, ma position politique est à l’opposé. Il n’empêche que, pour moi, le livre de Wade est important. Il l’est à deux niveaux: (i) plaisir intellectuel d’ouvrir les yeux sur un domaine duquel, comme tout un chacun, je détournais les yeux; (ii) malaise face à l’ « inconvenient truth » qu’il met en lumière et inquiétude quant à ses conséquences politiques et sociales.

Ce livre prend le contrepied du dogme selon lequel les races n’existent pas, l’évolution biologique s’est arrêtée avec l’émergence du langage et de la culture, la différence entre civilisations est uniquement culturelle. Ce dogme est fondateur des sciences humaines du XXe siècle; la plupart des biologistes s’y sont ralliés. Pourtant, il est objectivement faux. Chacun sait reconnaitre un Asiatique d’un Caucasien ou d’un Africain; les analyses forensiques identifient leurs squelettes avec confiance; la génétique ne laisse aucun doute. Bien sûr, les frontières entre races sont floues. Il le faut, c’est la définition. Si tel n’était pas le cas, ce ne serait pas des races, mais des espèces. Pourtant, le dogme est confortable parce qu’en rejetant la notion de race il croît rejeter le racisme qui lui, classe les humains sur une échelle de valeurs insupportable.

Ces considérations de base précisées, le livre se développe selon deux lignes. La première démontre que, depuis les quelque 40’000 ans pendant lesquelles les 3 races principales se sont petit à petit séparées, l’évolution biologique a continué. La couleur de la peau, la pilosité, les odeurs corporelles et beaucoup d’autres choses le prouvent. Même si les données sont beaucoup moins solides en ce qui concerne les hautes fonctions humaines déterminantes pour la culture et la nature des sociétés, par défaut au moins, il semble raisonnable d’admettre que cette évolution y joue aussi un rôle. Wade pousse loin cette hypothèse en explorant ce qu’elle pourrait signifier si l’évolution biologique était aussi significative à l’échelle de quelques siècles. Par exemple, il considère le cas de l’Angleterre, dont la population est relativement homogène depuis 1000 ans (Hastings: 1066) et pour laquelle les données sont abondantes. Il remarque que, comme c’est généralement le cas dans les nations développées, le QI corrèle avec le revenu. Il nous apprend aussi que, au temps de la renaissance, les familles aisées donnaient, à la génération suivante, deux fois plus de descendants que les familles pauvres. Ces faits sont les prémisses d’une évolution biologiques. Sans détour, Wade considère aussi le cas des Juifs. Il se demande si deux-mille ans à se concentrer sur la lecture critique des textes ne laissent pas quelques traces dans les gènes, comme d’ailleurs deux-mille ans d’apprentissage tout aussi intense, mais stérile des fonctionnaires chinois. La différence est-elle significative? Le moins que l’on puisse dire est qu’il est intéressant d’y réfléchir.

Alors que le livre de Wade était ma lecture quotidienne, nous visitions Londres en famille. Le chaos créatif de cette ville m’impressionnait. Quel cheni! Tout le monde fait – les architectes s’en donnent à coeur joie – mais où est l’urbanisme (photo). Allez voir Paris, c’est autre chose. Pourtant, contrairement à New York où l’on se croise comme on passe à côté d’un lampadaire, j’avais l’impression, que les londonien se voient.

IMG_2134IMG_2139

Prenons ce sympathique monsieur couché sur le Millennium Bridge, la récente passerelle pour piétons qui mène à la Tate Modern. Que fait-il? Il cache les vilains chewing gum sous une jolie petite peinture. Magnifique! Ah oui, ils sont créatifs ces anglais, et ils savent cohabiter. En Chine, c’est différent! En fait, ce genre de pensée sur la nature des gens, des groupes où des races nous habitent tous. Christine sait bien que les Bâlois ont l’humour dans leurs gènes; rien à voir avec les Zürichois! C’est une plaisanterie bien sûr, mais en rechercher la substance lors de la rencontre avec autrui n’est pas stupide. Chaque personne est différente, chaque groupe est différent, il est bien intéressant d’en prendre finement connaissance.

Seulement voilà, il y a 40’000 ans, l’Homo sapiens était tribal et brutal, probablement sans beaucoup s’améliorer avant le néolithique.  Depuis, il s’est un peu apprivoisé, mais le fond reste. Il continue de saisir toutes les occasions pour rejeter celui qui n’est pas de son clan, son groupe, sa nation ou sa race. Pour ce qui concerne la race, l’histoire montre à quel point il sait en prendre prétexte pour haïr. Le présent livre pourrait-il exacerber cette pathologie dramatique?

Oui, je vois cette possibilité, mais je vois aussi que, à tricher avec la réalité qui dérange, on risque pire encore. Ainsi, je suis inquiet, mais, je vais quand même continuer à lutter pour ce qui est, c’est-à-dire le fait que chaque homme est différent de tous les autres, et que la richesse humaine est dans cette diversité d’individus, de groupes, de cultures et de races. Les femmes aussi sont différentes des hommes et sauf pour quelques féministes attardés, le fait que le sexe de la biologie ne se réduise pas au genre de la culture est une richesse qui se découvre en s’approchant. Il en va de même pour toutes relations à autrui. L’appréciation et la tolérance se cultivent dans la rencontre. C’est à nous de faire en sorte qu’elle soit « win-win » (on pense évidemment aux réfugiés.) Il m’est arrivé d’avoir de la peine avec les arrivées tardives de ma jeune élève Fadumo. « Mais je suis africaine », m’a-t-elle fait valoir. Un autre l’avait exprimé joliment: « tu as la montre, j’ai le temps ». Riche leçon pour un agité comme je le suis. Win-Win. Merci!

 

Commentaire additionnel. L’hypothèse, selon laquelle l’évolution biologique des traits sociaux ou culturels se poursuit dans les temps modernes, peut-elle être démontrée? C’est à la biologie des populations d’y répondre. Justement, on trouve sur mon blog (http://www.dubochet.ch/jacques/?p=687#more-687) un court rapport à propos d’un article – difficile – publié dans Nature du 23 juillet 2015 (pp 459 ss) qui identifie 3 traits humains qui sont actuellement soumis à une sélection biologique positive: la taille, la capacité cognitive, et le niveau d’éducation. Ceci est une donnée objective soutenant l’hypothèse de Wade selon laquelle l’évolution biologique des hautes fonctions humaines se poursuit actuellement.
Commentaire du 15.10. 15. Il a fallu le Human Genome Project et 12 (?) ans de travail pour séquencer le premier génome humain. En ce mois de septembre se termine le « 1000 human genome projet » et dans la même no. de Nature apparait un premier article du UK10k project (10K pour 10’000). Ça ne va pas diminuer. Tout le monde insiste pour vanter ainsi les promesses de la médecine et la génétique individuelle mais avec elle viennent aussi  forcément le regroupement en groupes à tous les niveaux, familles, ethnies ou races.

 

Analyse par C. Murray dans le Wall Street J. du 2.5.2014            

http://www.wsj.com/articles/SB10001424052702303380004579521482247869874

A TROUBLESOME INHERITANCE. By Nicholas Wade. The Penguin Press, 278 pages, $27.95

A scientific revolution is under way—upending one of our reigning orthodoxies.

America’s modern struggle with race has proceeded on three fronts. The legal battle effectively ended a half-century ago with the Civil Rights Act of 1964. The second front, the battle against private prejudice, has not been won so decisively, but the experiences of Cliven Bundy and Donald Sterling in the past few weeks confirm a longstanding truth about American society: Expressions of racial prejudice by public figures are punished swiftly and severely.

The third front is different in kind. This campaign is waged not against actual violations of civil rights or expressions of prejudice or hatred, but against the idea that biological differences among human populations are a legitimate subject of scholarly study. The reigning intellectual orthodoxy is that race is a « social construct, » a cultural artifact without biological merit.

 

The orthodoxy’s equivalent of the Nicene Creed has two scientific tenets. The first, promulgated by geneticist Richard Lewontin in « The Apportionment of Human Diversity » (1972), is that the races are so close to genetically identical that « racial classification is now seen to be of virtually no genetic or taxonomic significance. » The second, popularized by the late paleontologist Stephen Jay Gould, is that human evolution in everything but cosmetic differences stopped before humans left Africa, meaning that « human equality is a contingent fact of history, » as he put it in an essay of that title in 1984.

Since the sequencing of the human genome in 2003, what is known by geneticists has increasingly diverged from this orthodoxy, even as social scientists and the mainstream press have steadfastly ignored the new research. Nicholas Wade, for more than 20 years a highly regarded science writer at the New York Times , has written a book that pulls back the curtain.

 

It is hard to convey how rich this book is. It could be the textbook for a semester’s college course on human evolution, systematically surveying as it does the basics of genetics, evolutionary psychology, Homo sapiens’s diaspora and the recent discoveries about the evolutionary adaptations that have occurred since then. The book is a delight to read—conversational and lucid. And it will trigger an intellectual explosion the likes of which we haven’t seen for a few decades.

The title gives fair warning: « A Troublesome Inheritance: Genes, Race and Human History. » At the heart of the book, stated quietly but with command of the technical literature, is a bombshell. It is now known with a high level of scientific confidence that both tenets of the orthodoxy are wrong.

Mr. Lewontin turns out to have been mistaken on several counts, but the most obvious is this: If he had been right, then genetic variations among humans would not naturally sort people into races and ethnicities. But, as Mr. Wade reports, that’s exactly what happens. A computer given a random sampling of bits of DNA that are known to vary among humans—from among the millions of them—will cluster them into groups that correspond to the self-identified race or ethnicity of the subjects. This is not because the software assigns the computer that objective but because those are the clusters that provide the best statistical fit. If the subjects’ ancestors came from all over the inhabited world, the clusters that first emerge will identify the five major races: Asians, Caucasians, sub-Saharan Africans, Native Americans and the original inhabitants of Australia and Papua New Guinea. If the subjects all come from European ancestry, the clusters will instead correspond to Italians, Germans, French and the rest of Europe’s many ethnicities. Mr. Lewontin was not only wrong but spectacularly wrong. It appears that the most natural of all ways to classify humans genetically is by the racial and ethnic groups that humans have identified from time out of mind.

Stephen Jay Gould’s assurance that significant evolution had stopped before humans left Africa has also proved to be wrong—not surprisingly, since it was so counterintuitive to begin with. Humans who left Africa moved into environments that introduced radically new selection pressures, such as lethally cold temperatures. Surely, one would think, important evolutionary adaptations followed. Modern genetic methods for tracking adaptations have established that they did. A 2009 appraisal of the available genome-wide scans estimated that 14% of the genome has been under the pressure of natural selection during the past 30,000 years, long after humans left Africa. The genes under selection include a wide variety of biological traits affecting everything from bone structure and diet to aspects of the brain and nervous system involving cognition and sensory perception.

The question, then, is whether the sets of genes under selection have varied across races, to which the answer is a clear yes. To date, studies of Caucasians, Asians and sub-Saharan Africans have found that of the hundreds of genetic regions under selection, about 75% to 80% are under selection in only one race. We also know that the genes in these regions affect more than cosmetic variations in appearance. Some of them involve brain function, which in turn could be implicated in a cascade of effects. « What these genes do within the brain is largely unknown, » Mr. Wade writes. « But the findings establish the obvious truth that brain genes do not lie in some special category exempt from natural selection. They are as much under evolutionary pressure as any other category of gene. »

Let me emphasize, as Mr. Wade does, how little we yet know about the substance of racial and ethnic differences. Work in the decade since the genome was sequenced has taught us that genetically linked traits, even a comparatively simple one like height, are far more complex than previously imagined, involving dozens or hundreds of genes, plus other forms of variation within our DNA, plus interactions between the environment and gene expression. For emotional or cognitive traits, the story is so complicated that we are probably a decade or more away from substantial understanding.

As the story is untangled, it will also become obvious how inappropriate it is to talk in terms of the « inferiority » or « superiority » of groups. Consider, for example, the Big Five personality traits: openness, conscientiousness, extraversion, agreeableness and neuroticism. What are the ideal points on these continua? They will differ depending on whether you’re looking for the paragon of, say, a parent or an entrepreneur. And the Big Five only begin to tap the dozens of ways in which human traits express themselves. Individual human beings are complicated bundles of talents, proclivities, strengths and flaws that interact to produce unexpected and even internally contradictory results. The statistical tendencies (and they will be only tendencies) that differentiate groups of humans will be just as impossible to add up as the qualities of an individual. Vive les différences.

The problem facing us down the road is the increasing rate at which the technical literature reports new links between specific genes and specific traits. Soon there will be dozens, then hundreds, of such links being reported each year. The findings will be tentative and often disputed—a case in point is the so-called warrior gene that encodes monoamine oxidase A and may encourage aggression. But so far it has been the norm, not the exception, that variations in these genes show large differences across races. We don’t yet know what the genetically significant racial differences will turn out to be, but we have to expect that they will be many. It is unhelpful for social scientists and the media to continue to proclaim that « race is a social construct » in the face of this looming rendezvous with reality.

After laying out the technical aspects of race and genetics, Mr. Wade devotes the second half of his book to a larger set of topics: « The thesis presented here assumes . . . that there is a genetic component to human social behavior; that this component, so critical to human survival, is subject to evolutionary change and has indeed evolved over time; that the evolution in social behavior has necessarily proceeded independently in the five major races and others; and that slight evolutionary differences in social behavior underlie the differences in social institutions prevalent among the major human populations. »

To develop his case, Mr. Wade draws from a wide range of technical literature in political science, sociology, economics and anthropology. He contrasts the polities and social institutions of China, India, the Islamic world and Europe. He reviews circumstantial evidence that the genetic characteristics of the English lower class evolved between the 13th century and the 19th. He takes up the outsize Jewish contributions to the arts and sciences, most easily explained by the Jews’ conspicuously high average IQ, and recounts the competing evolutionary explanations for that elevated cognitive ability. Then, with courage that verges on the foolhardy, he adds a chapter that incorporates genetics into an explanation of the West’s rise during the past 600 years.

Mr. Wade explicitly warns the reader that these latter chapters, unlike his presentation of the genetics of race, must speculate from evidence that falls far short of scientific proof. His trust in his audience is touching: « There is nothing wrong with speculation, of course, as long as its premises are made clear. And speculation is the customary way to begin the exploration of uncharted territory because it stimulates a search for the evidence that will support or refute it. »

I fear Mr. Wade’s trust is misplaced. Before they have even opened « A Troublesome Inheritance, » some reviewers will be determined not just to refute it but to discredit it utterly—to make people embarrassed to be seen purchasing it or reading it. These chapters will be their primary target because Mr. Wade chose to expose his readers to a broad range of speculative analyses, some of which are brilliant and some of which are weak. If I had been out to trash the book, I would have focused on the weak ones, associated their flaws with the book as a whole and dismissed « A Troublesome Inheritance » as sloppy and inaccurate. The orthodoxy’s clerisy will take that route, ransacking these chapters for material to accuse Mr. Wade of racism, pseudoscience, reliance on tainted sources, incompetence and evil intent. You can bet on it.

All of which will make the academic reception of « A Troublesome Inheritance » a matter of historic interest. Discoveries have overturned scientific orthodoxies before—the Ptolemaic solar system, Aristotelian physics and the steady-state universe, among many others—and the new received wisdom has usually triumphed quickly among scientists for the simplest of reasons: They hate to look stupid to their peers. When the data become undeniable, continuing to deny them makes the deniers look stupid. The high priests of the orthodoxy such as Richard Lewontin are unlikely to recant, but I imagine that the publication of « A Troublesome Inheritance » will be welcomed by geneticists with their careers ahead of them—it gives them cover to write more openly about the emerging new knowledge. It will be unequivocally welcome to medical researchers, who often find it difficult to get grants if they openly say they will explore the genetic sources of racial health differences.

The reaction of social scientists is less predictable. The genetic findings that Mr. Wade reports should, in a reasonable world, affect the way social scientists approach the most important topics about human societies. Social scientists can still treat culture and institutions as important independent causal forces, but they also need to start considering the ways in which variations among population groups are causal forces shaping those cultures and institutions.

How long will it take them? In 1998, the biologist E.O. Wilson wrote a book, « Consilience, » predicting that the 21st century would see the integration of the social and biological sciences. He is surely right about the long run, but the signs for early progress are not good. « The Bell Curve, » which the late Richard J. Herrnstein and I published 20 years ago, should have made it easy for social scientists to acknowledge the role of cognitive ability in shaping class structure. It hasn’t. David Geary’s « Male/Female, » published 16 years ago, should have made it easy for them to acknowledge the different psychological and cognitive profiles of males and females. It hasn’t. Steven Pinker’s « The Blank Slate, » published 12 years ago, should have made it easy for them to acknowledge the role of human nature in explaining behavior. It hasn’t. Social scientists who associate themselves with any of those viewpoints must still expect professional isolation and stigma.

« A Troublesome Inheritance » poses a different order of threat to the orthodoxy. The evidence in « The Bell Curve, » « Male/Female » and « A Blank Slate » was confined to the phenotype—the observed characteristics of human beings—and was therefore vulnerable to attack or at least obfuscation. The discoveries Mr. Wade reports, that genetic variation clusters along racial and ethnic lines and that extensive evolution has continued ever since the exodus from Africa, are based on the genotype, and no one has any scientific reason to doubt their validity.

And yet, as of 2014, true believers in the orthodoxy still dominate the social science departments of the nation’s universities. I expect that their resistance to « A Troublesome Inheritance » will be fanatical, because accepting its account will be seen, correctly, as a cataclysmic surrender on some core premises of political correctness. There is no scientific reason for the orthodoxy to win. But it might nonetheless.

So one way or another, « A Troublesome Inheritance » will be historic. Its proper reception would mean enduring fame as the book that marked a turning point in social scientists’ willingness to explore the way the world really works. But there is a depressing alternative: that social scientists will continue to predict planetary movements using Ptolemaic equations, as it were, and that their refusal to come to grips with « A Troublesome Inheritance » will be seen a century from now as proof of this era’s intellectual corruption.

—Mr. Murray is the W.H. Brady Scholar at the American Enterprise Institute.

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