A Troublesome Inheritance: Genes, Race and Human History, by Nicholas Wade (Penguin Press, 288 pp., $27.95)
In 2001, the New England Journal of Medicine published an editorial provocatively titled Racial Profiling in Medical Research. The author, Robert Schwartz, reiterated the commonly held view that no biological basis exists for race, and then argued that physicians should not consider race in their research or medical practice. This prompted a sharp response from geneticist Neil Risch, who pointed out that numerous studies had demonstrated significant genetic differences among humans based on continental ancestry, suggesting evidence of five distinct races. Among the reasons for recognizing such variations: research shows that people of different races sometimes vary in their responses to medicines.
The talented New York Times science reporter, Nicholas Wade, recounted this exchange in his 2006 book, Before the Dawn: Recovering the Lost History of Our Ancestors, which contained a short section on how the latest genetic research challenges the received wisdom about race and biology. Now, eight years later, Wade is back with a provocative book on that subject. In A Troublesome Inheritance: Genes, Race and Human History, Wade seeks to topple a whole set of related beliefs about human development prominent among social scientists, especially those on the left.
The decoding of the human genome, completed in 2003, has given added weight to the view that there is indeed a biological basis for race, Wade argues. More broadly, he contends, scientific advances now challenge the widespread notion that culture alone, with no contribution from genetics, is responsible for differences among human populations. To support that idea, many social scientists contend that human evolution all but stopped when the first modern humans emerged from Africa some 50,000 years ago. Wade, by contrast, argues that there is now persuasive evidence that human evolution has been recent, copious and regional and that understanding the continuing role of natural selection and its impact on our behavior may help illuminate everything from the origins of the Industrial Revolution to why some cultures fail.
The mere existence of such disputes may startle some readers. These days, you can find an abundance of media reports about religious fundamentalists denying the existence of evolution. But Wade concerns himself with evolution rejectionists on the academic left, who draw much less attention, but who, he contends, have sought to shut down whole branches of important research. Groups like the American Anthropological Association and the American Sociological Association issue declarations calling race a social construct and warn against the danger of contributing to the popular conception of race as biological. Wade reminds us that the early role of genetics in public policy included some dark episodes—as when some American states tried to sterilize feeble-minded people in the 1930s, for example—but he argues that todays left-leaning social scientists use the specter of eugenics to their political advantage. Their fields remain resolutely Marxist, and they resist the notion that heredity predisposes the human mind to act in certain ways, because they wish government to mold Socialist man in its desired image, and see genetics as an impediment to the power of the state.
In Before the Dawn, Wade explained at length how the rapidly advancing field of genetics has improved our understanding of human origins. In a helpful section of the new book, The Peopling of the World, Wade describes how scientific discoveries have given us a more detailed picture of how humans emerged from Africa and gradually spread throughout the world. The process, known as population budding, took tens of thousands of years; some people moved on to new locations as local resources grew strained. Once they arrived at a suitable location, most stayed in place, becoming geographically isolated from those they had left behind—and from those who, subsequently, moved on again. As groups separated from one another, they developed genetic variations that we can identify today. The fact that people were pretty much locked within their home territories until modern times is one of the surprises that has come out of the genome, writes Wade. The worlds human population is very finely structured in each geographic region in terms of its genetics, with human genomes changing recognizably every few miles across the globe. These distinct groups, living in vastly different environments in some cases, faced a variety of powerful evolutionary stresses that shaped everything from their physical characteristics to their behavior, and subsequently influenced the nature of their societies—including their institutions.
The mapping of the human genome, with its extraordinary complexity, has helped us understand this picture. Initial research showed that all humans shared the same basic genes and even most of the same so-called alleles, or alternate forms of genes. But over time, geneticists have come to understand that humans cluster into groups based on the frequency that alleles reoccur. The most basic clusters correspond to continental ancestry. Five are recognizable in the genome. The first belongs to those whose ancestors remained in sub-Saharan Africa. The other four pertain to those whose ancestors traveled and ultimately settled in Europe, in East Asia, in the Americas, or in Australia and the Pacific Islands. Subsequent studies based on more refined DNA markers have allowed researchers to see more numerous and distinct groupings, which frequently correspond to what we might describe as ethnicities. The more DNA markers that are used . . . the more subdivisions can be established in the human population, Wade observes. Geneticists now estimate that about 14 percent of the human genome has changed under evolutionary pressures over the last 30,000 years, forging differences among us. Some scientists have discounted these changes as insignificant and merely cosmetic, but as Wade asserts, small shifts in isolated populations can produce enormous transformations over time in behavior, and hence in entire societies.
Wade also wrestles with another set of deeply held creeds in the social sciences: that were all blank slates, with no innate human nature, and that everything we become, we learn from our environment. Dissenters have chipped away at that faulty idea for decades, but despite mounting scientific evidence, theyve had only partial success changing perceptions. The Harvard evolutionary biologist Edward O. Wilson scored a significant blow 40 years ago with his book Sociobiology: The New Synthesis, which described the role natural selection played in the rise of such basic human behaviors as aggression and altruism. In the early 1990s, the eminent political scientist James Q. Wilson published The Moral Sense, which argued that humans were naturally endowed with a moral code that had developed, in part, because evolution favored those imbued with such traits as sympathy, self-control, and a desire for fairness. The evolutionary psychologist Steven Pinker tried to lay the whole controversy to rest with his 2002 tome, The Blank Slate: The Modern Denial of Human Nature, which mustered all the evidence in favor of the idea that heredity plays a role in human thought and behavior.
Wade would go further. He offers the self-evident observation that human societies differ significantly, then argues that civilizations have been deeply shaped by their respective histories as each responded to the specific challenges of its environment. In particular, the institutions of individual societies are rooted in and grow out of our social behaviors—ranging from an instinct for cooperation to a willingness to fight to the death to protect group members—and these have, to one degree or another, a genetic basis. Though genes merely provide us with a predisposition to act in certain ways (were not always cooperative, obviously), and many individuals chart their own courses, when a significant portion of a population carries with it a predisposition toward certain actions, the results are profound.
Wade might have stopped here, having provided enough controversy to last a lifetime, but he ploughs on with a series of speculative observations. In a chapter audaciously titled The Recasting of Human Nature, he expands on his observations about how natural selection shapes societies by drawing on the works of economists like Thomas Sowell on ethnic minorities (especially in Sowells books Conquests and Cultures and Migrations and Cultures) and Daron Acemoğlu on nations (Why Nations Fail, written with the political scientist James Robinson). Observing that experts still argue over what forces produced the Industrial Revolution, Wade magnifies the ideas of economic historian Gregory Clark, who suggested that an evolutionary behavioral change might have triggered the great economic advances that began in the late eighteenth century. Wade admits that there is no direct evidence of any genetic link—no capitalist gene that science has uncovered, if you will—but he does his best to shape a plausible scenario anyway. As if this isnt enough, Wades penultimate chapter, The Rise of the West, argues that natural selection similarly helped produce European societies that were open and innovative, which enabled them to achieve a surprising degree of dominance in many spheres. Given the influence that multiculturalists have on todays American campuses, its unlikely that Wade will be delivering any commencement address anytime soon.
Knowledge is usually considered a better basis for policy than ignorance, Wade optimistically concludes. This book has been an attempt, undoubtedly imperfect, to dispel the fear of racism that overhangs discussions of human group differences. Unfortunately, this bold and often innovative book is likely to bring down on Wade exactly the kind of ugly charges hed like to avoid. But some readers, scientists among them, will be grateful for his willingness to raise subjects often banned from polite discussion.