Nicholas Wade on race: Genes and evolution trump culture in shaping human differences

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There are few subjects more stigmatized and taboo in our culture than race, especially outlining the biological differences between the races. Nevertheless, as technology of genetic sequencing has become widely available, there is mounting evidence of the biological differences between groups of people. Nicholas Wade, a venerable science writer for the New York Times, has taken on the subject in his new book, A Troublesome Inheritance: Genes Race and Human History.

Writing in the Wall Street Journal, think tank scholar and author of The Bell Curve Charles Murray, reviews Wade’s book. Murray begins by outlining what he calls the current politically correct orthodoxy on race: race is only a social construct, there are no significant biological differences between races and human genes are static, we stopped evolving when our ancestors began migrating out of Africa. Then Murray, using Wade’s evidence, takes them down, starting with the fact that human populations sort into races based on their genes. If you’re looking at the world population, five large population groups arise: Asians, Caucasians, sub-Saharan Africans, Native Americans and the original inhabitants of Australia and Papua New Guinea. If you’re looking at Europeans alone group differences between French, Italian, Spanish, etc. come from the data.

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… 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.

Wade does not stop at outlining the genetic differences of race created by evolution since the human diaspora. He also points out that the genetic differences that create race, like many other genes, are still experiencing selection pressures from evolution. Not only do these distinct genetic groups sort along the lines of the five largest ethnic groups in the world, but evolution is working differently within these groups. “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,” Murray writes.

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.

Murray finds the second half of Wade’s book a bit less successful because of his inclusion of speculative research, contrasting the well-documented findings in the first half of the book. The inclusion of this research makes the entire text more vulnerable to critics who will seek to dismiss the premise entirely.

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.

Murray is hopeful that “A Troublesome Inheritance” will help change academic perceptions of race by opening up the social science dialog to accepting genetics and by eliminating the prejudice researchers face when applying for grants to look at health disparities between racial and ethnic groups. But, he is a realist about how the book will be received:

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.

Read full original articleBook Review: ‘A Troublesome Inheritance’ by Nicholas Wade

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