Genes and Race: The Distant Footfalls of Evidence

A review of Nicholas Wade’s book, “A Troublesome Inheritance: Genes, Race and Human History.”

In this book NYT science writer Nicholas Wade advances two simple premises: firstly, that we should stop looking only toward culture as a determinant of differences between populations and individuals, and secondly, that those who claim that race is only a social construct are ignoring increasingly important findings from modern genetics and science. The guiding thread throughout the book is that “human evolution is recent, copious and regional” and that this has led to the genesis of distinct differences and classifications between human groups. What we do with this evidence should always be up for social debate, but the evidence itself cannot be ignored.

That is basically the gist of the book. It’s worth noting at the outset that at no point does Wade downplay the effects of culture and environment in dictating social, cognitive or behavioral differences–in fact he mentions culture as an important factor at least ten times by my count–but all he is saying is that, based on a variety of scientific studies enabled by the explosive recent growth of genomics and sequencing, we need to now recognize a strong genetic component to these differences.

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The second part of the book is really the meat of the story and Wade is on relatively firm ground here. He details a variety of studies based on tools like tandem DNA repeats and single nucleotide polymorphisms (SNPs) that point to very distinctive genetic differences between populations dictating both physical and mental traits. Many of the genes responsible for these differences have been subject to selection in the last five thousand years or so, refuting the belief that humans have somehow “stopped evolving” since they settled down into agricultural communities. For me the most striking evidence that something called race is real comes from the fact that when you ask computer algorithms to cluster genes based on differences and similarities in an unbiased manner, these statistical programs consistently settle on the five continental races as genetically distinct groups–Caucasian, East Asian, African, Native American and African Aboriginal. {snip}

Wade also demolishes the beliefs of many leading thinkers who would rather have differences defined almost entirely by culture–these include Stephen Jay Gould who thought that humans evolved very little in the last ten thousand years (as Wade points out, about 14% of the genome has been under active selection since modern humans appeared on the scene), and Richard Lewontin who perpetuated a well-known belief that the dominance of intra as opposed to inter individual differences makes any discussion of race meaningless. As Wade demonstrates through citations of solid research, this belief is simply erroneous since even small differences between populations can translate to large differences in physical, mental and social features depending on what alleles are involved; Lewontin and his followers’ frequent plea that inter-group differences are “only 15%” thus ends up essentially translating to obfuscation through numbers. {snip}

The last part of the book is likely to be regarded as more controversial because it deals mainly with effects of genetics on cognitive, social and personality traits and is much more speculative. However Wade fully realizes this and also believes that “there is nothing wrong with speculation, of course, as long as its premises are made clear”, and this statement could be part of a scientist’s credo. The crux of the matter is to logically ask why genes would also not account for mental differences between races if they do account for physical differences. The problem there is that although the hypothesis is valid, the evidence is slim for now. Some of the topics that Wade deals with in this third part are thus admittedly hazy in terms of evidence. For instance there is ample contemplation about whether a set of behavioral and genetic factors might have made the West progress faster than the East and inculcated its citizens with traits conducive to material success. However Wade also makes it clear that “progressive” does not mean “superior”; what he is rather doing is sifting through the evidence and asking if some of it might account for these more complex differences in social systems. Similarly, while there are pronounced racial differences in IQ, one must recognize the limitations of IQ, but more importantly should recognize that IQ says nothing about whether one human is “better” or “worse” than another; in fact the question is meaningless.

Wade brings a similar approach to exploring genetic influences on cognitive abilities and personality traits; evidently, as he recognizes, the evidence on this topic is quite slim. He looks at the effects of genes on traits as diverse as language, reciprocity and propensity to dole out punishment. This discussion makes it clear that we are just getting started and there are many horizons that will be uncovered in the near future; for instance, tantalizing hints of links between genes for certain enzymes and aggressive or amiable behavior are just emerging. If I have a criticism of the book it is that in his efforts to cover extensive ground, Wade sometimes gives short shrift to research on interesting topics like oxytocin and hormonal influences. But what he does make clear is that the research opportunities in the field are definitely exciting, and scientists should not have to tiptoe around these topics for political reasons.

Overall I found this book extremely well-researched, thoughtfully written and objectively argued. The many researchers whose work Wade cites makes the writing authoritative; on the other hand, where speculation is warranted or noted he usually explicitly points it out as such. {snip}

But the real lesson of the book should not be lost on us: A scientific topic cannot be declared off limits or whitewashed because its findings can be socially or politically incendiary; as Wade notes, “Whether or not a thesis might be politically incendiary should have no bearing on the estimate of its scientific validity.” {snip}

Ultimately Wade’s argument is about the transparency of knowledge. He admonishes some of the critics–especially some liberal academics and the American Anthropological Association–for espousing a “culture only” philosophy that is increasingly at odds with scientific facts and designed mainly for political correctness and a straitjacketed worldview. I don’t think liberal academics are the only ones guilty of this attitude but some of them certainly embrace it. Liberal academics, however, have also always prided themselves on being objective examiners of the scientific truth. Wade rightly says that they should join hands with all of us in bringing that same critical and honest attitude to examining the recent evidence about race and genetics. Whatever it reveals, we can be sure that as human beings we will try our best not to let it harm the cause of our fellow beings. After all we are, all of us, human beings first and scientists second.