A Troublesome Inheritance: Genes, Race and Human History
Nicholas Wade, The Penguin Press, New York, 2014
Nicholas Wade is the former deputy editor of Nature and a veteran of both Science and The New York Times. He has attempted to make a case for the existence of genetic differences between the various human races—differences that matter—in his recent book A Troublesome Inheritance: Genes, Race and Human History.1 I can sum up my opinion of this book in one word: disappointing. I was almost in his camp. I know there are genetic differences between Europeans and Africans and between East Asians and Australian natives, etc., and I was willing to be persuaded even more. Do these differences matter? Are there intrinsic quantifiable differences between the world’s major people groups? In the end, not only did the book utterly fail to answer these questions, but it pushed me in the opposite direction from the author’s main arguments.
While reading this, I felt like one of Galileo’s opponents, who could possibly have been persuaded. But the fact that Galileo used demonstrably false examples to support his theory (like the idea that tides are created by centrifugal forces) perhaps made them disinclined to absorb the rest. Here, we know that racial differences exist, but there is nothing in this book to demonstrate that these have any measurable effect.
His main thesis is that, since traits like skin colour have evolved in populations, the same should be true of social behaviours (p. 41). Thus, genetic differences among the races might be able to account for differences in things like IQ and aggressiveness. He uses, and assumes, the lame definition that evolution simply equals ‘change’. And he strangely equates evolutionary success with things like IQ and farming, whereas evolution is really only defined in terms of reproduction. The only rule in evolutionary theory is ‘survival of the fittest’ and the ‘fittest’ is defined as the one who has the most descendants in subsequent generations. Essentially, he who dies with the most surviving children wins! Thus, IQ is irrelevant in evolutionary struggle unless IQ conveys an increased ability, on average, for one’s children to survive.
He discusses the difference among various countries and peoples on economic and cultural lines, as if this tells us anything. While it may (or may not!) be true that rich people can feed more children and thus might be expected to have more surviving offspring, Darwin himself lamented the fact that the opposite was true even in his day. And there is more than one way to have an overrepresentation of one’s offspring in future generations. One can either have a lot of children or one can kill off the competitors. Indeed, this was one of the strategies prescribed by another Darwin disciple, Margaret Sanger.2
The book starts out with a history of racism since Darwin. Here the author tried, but failed, to distance his views from those of many prior evolutionists. Chapter 2 is titled “Perversions of Science”, and here he spends considerable time on the eugenics movement, Nazi Germany, and other ‘misapplications’ of Darwinian theory. Amazingly, he completely ignores the fact that the early eugenics movement can be considered a ‘Darwin family business’.3 He also intimates that German eugenicists learned their craft from the Americans. While it is true that the United States had a large and influential eugenics community, this certainly does not mean Germany did not have one of its own! In fact, the German Society for Race Hygiene was the world’s first eugenics society.4 He gives us several quotes from people claiming Darwin’s views were corrupted by racists, even quoting from Darwin himself on occasion. The problem is that Darwin is only selectively quoted. Why not use this:
Here, Darwin states clearly that he believes the civilized races (by which he meant Europeans and perhaps Asians, although he classed them lower than Europeans) will eventually kill off the less superior brown and black peoples of the world because dark-skinned people are inferior. Thus, eugenics and racism are certainly not foreign concepts to Darwinism. There is difficulty with pinning the label of ‘racist’ on Darwin, who did help support the eventually successful anti-slavery work of Wilberforce.6 But even overlooking the fact that the connection between racism and slavery is not as clear-cut as commonly believed,7 at most all this means is that Darwin was a complex person and, as most people are, was inconsistent in the application of his own conclusions.
In the end, Wade makes several weak appeals to our advanced modern culture, suggesting that this alone will be a bulwark against future abuses. We are more civilized than at that time, right? It can never happen again, right? But why not? This question is never answered, yet it is especially pertinent if we are only evolved from lower forms of life.
He admits chimps have not changed much (p. 42), and then appeals to the much-debated ‘Savannah Hypothesis’8 in an attempt to explain why humans have gone through comparatively rapid advances, including the evolution of our upright posture and our tendency toward monogamy (p. 45). There is no model here, no math, only evolutionary assumptions hiding behind a thin scientific veil—for if we came from a common ancestor, chimps have had similar environmental challenges, a similar number of generations, similar selection pressures, and a similar number of accumulated mutations. Therefore, all else being equal, coming down from the trees is all that was required for humans to achieve such remarkable evolutionary success.
And this is perhaps the Achilles’ heel of his work. He never appeals to real models of natural selection. It is easy enough to imagine a species changing over time, but with what selection pressures, what level of mutation, etc., he never says.
He spends a lot of time talking about human history, which, although fascinating, is a distraction. In the end he only gives a few examples of genetic traits that affect human behaviour. According to Wade, human behaviour must reflect the underlying genes, even if “not much is yet known about the genetic basis of human social behavior” (p. 51). This might explain why he posits so very few examples to support his thesis.
Oxytocin promotes trust and cooperativeness in certain social contexts, helping people to form bonds of friendship, and the level of expression of oxytocin varies among people. Therefore, voila! “It’s easy to see how natural selection could increase the general degree of trust in human societies.” But here he is assuming the power of natural selection and ignoring the many confounding factors that prevent selection from operating efficiently (see below).
The MAO-A gene. People with 3–5 copies of the promoter for this gene are normal, but those with just two copies “have much higher levels of delinquency” (p. 55).
Figure 1. There are a range of skin colours even among the people living in Asia. These colours, like most other genetic traits, are represented by clines, not distinct boundaries, meaning it is notoriously difficult to divide people into ‘races’. Despite the best effort of the author, he was not able to overcome this simple objection.
Lactose tolerance is high in Scandinavian countries and decreases as one progresses from there. Three different mutations with the same effect can be found in East Africa. This is perhaps the best example of the effects of natural selection he discusses, but even then this only applies to raw milk. Cheese, yogurt, and other dairy products often contain little to no lactose and are eaten worldwide with no gastrointestinal distress. Where is the selective advantage of eating raw milk in these two regions when processed milk products are readily available and reasonably tolerated in other cultures as well?
Dark skin prevents the destruction of folic acid by UV (p. 86). Light skin allows for more efficient production of vitamin D. And the light skin of Europeans is caused by different genetic factors than the light skin of Asians (pa 87) (figure 1). The genetics of skin colour are both complex and fascinating. One gene, MC1R, is almost invariant among Africans but highly variable among Europeans (p. 87). The thought is that selection has been reduced in Europeans, allowing for mutations to freely accumulate. Another gene, SLC24A5, has the opposite pattern (p. 88). Europeans are homogenous while Africans have quite a bit of diversity (even though all Africans have an alanine in the 111th codon).
There is a variant of the EDARV370A (pp. 88–90) gene found in East Asians and Native Americans at high frequency (70–90%). It causes a multitude of effects, including hair thickness, shape of the teeth, the number of sweat glands, and breast size in females. He claims natural selection must have done this, but how does NS deal with pleiotropic effects like this, and which trait was the focus of selection?
Another gene discussed is ABCC11 (pp. 90–91). Most Asians carry a variant that causes dry ear wax. It also creates less body odour (because there is less oil for bacteria to decompose). He claims natural selection would have benefitted less smelly people among people who spent many months in confined spaces to escape the cold. Yet the ‘smelly’ people have had no problem having children!
How did modern human society emerge? Through natural selection, according to Wade. Yet, while making his arguments, he completely ignores confounding factors like epigenetics, religion, human will, and the fact that humans are imbued with the ‘image of God’ (Genesis 1).
Also, there is no such thing as genetic predestination, and the author admits this when he says, “genes don’t determine human behavior; they merely create a propensity to behave in a certain way” (p. 57). But herein lies the rub—without a hard determinacy, natural selection sees a soft and malleable target. Environment, culture, religion, history, geography, individual will, and epigenetics all influence behaviour and interfere with genetic selection. The resulting effect of these combined forces makes untangling the specific contribution of genetics to the human condition like trying to sever the Gordian Knot with a butter knife.
He discusses Africa and wonders why it has lagged so far behind the rest of the world in terms of development. He specifically mentions Ghana as an example, saying it was comparable to South Korea in the 1960s but its GNP per capita is now but 1⁄15 that of its Asian counterpart (pp. 182–183). Yet it is a tragic mistake to assume Africa is homogenous, for when one crosses the border from Ghana into neighboring Togo one enters a much poorer country. Is it genetics that separates the two counties? Hardly! In fact the difference has been strongly linked to the exclusion of Protestant missionaries from Togo by the French colonial government.10 Once again, there is so much noise in the system that genetics makes no difference.
Importantly, when discussing the stark differences between North and South Korea, he says, “the same set of social behaviours [controlled as they are by genetics] can support either good or bad institutions” (p. 179). But does this not invalidate his entire thesis? Here, two populations with nearly identical gene frequencies are advancing along dramatically different lines. The cultural and historical noise is completely overwhelming the genetic signal!
Throughout the book, he is wrestling with the old ‘nurture vs nature’ argument and trying to conclusively answer on the side of nature, but he continually stumbles.
For example, he mentions that the 10–15-point average IQ differences that exist between various European countries disappear when those people come to the United States, and then says:
But why does he then spend so much time discussing the apparently more advanced intelligence of Jews11 and the supposed cultural backwardness of Africa? When taken as a whole, the differences between these two groups are less than the 10–15 points that exist on different sides of an artificial border that separates genetically indistinguishable people in Europe. The only answer here is culture.
He goes through the history of how we have distanced ourselves from old notions of race, citing eminent scholars like Winthrop Jordan (p. 72), Ashley Montagu, Franz Boas, Craig Venter, Jared Diamond, Francis Collins, and Jerry Coyne (pp. 68–69), who disagree with his position. But this means the burden of proof is on the author, and he provides little evidence to support his views.
Wade attempts to divide the world population into three major races (Caucasians, Asians, and Africans). He then adds two supplemental races, Native Americans and Austronesians (natives of Australia and Papua New Guinea). While doing so, however, he demonstrates that the races blend in the transition zones (i.e. there are no clear demarcations), and even cites Winthrop Jordan making this claim at length (p. 72). Is this a problem? Not for him, because computer programs can cluster people into distinct categories that fall into his three-race model. I find this problematic for several reasons. First of all, Asians and Europeans, although distinct, are closer to one another than either group is to many Africans. In fact, there is as much genetic diversity within Africa as within the rest of the world put together, and different people in Africa can be farther apart genetically than someone from Iceland is from someone from Cambodia. Why does Wade not refer to several African ‘races’?
He shows the fallacy of his own conclusions when he says, “One reason that races exist, though not distinctly, is that the features characteristic of a race are often distributed along a gradient” (p. 92). He says that the inability of scientists to come to a consensus on the number of races “doesn’t mean that races don’t exist, only that it is a matter of judgment as to how to define them” (p. 92). He admits that dividing the population into five continental-based races is arbitrary, even though “it makes practical sense” (p. 94). This is not hard science.
In the postscript, we learn that he has also authored a book about the role of religion in human societies. Yet, there is scant mention of religious practice and how it has influenced human societies in this book. He notes that human children are naturally cooperative, naturally helpful and naturally group with other humans (p. 48), but ignores the possibility that this is because we are all made in the image of God. Instead, he resorts to armchair rumination in order to explain it away.
In the one place where he does discuss religion directly, he shows his hand as a rabid anti-Christian when he claims that Christianity came about when the Apostle Paul “seamlessly wraps Judaism around the mystery cult creed of an agricultural vegetation god who dies in the fall and is resurrected in the spring” (p. 211). He goes on to say the intellectual Jews were not attracted to the more emotional early Christianity. Thus, he claims, there was an IQ difference between the two groups from the earliest times. Tell that to Paul, who “trained at the feet of Gamaliel” (Acts 22:3), the foremost Jewish scholar of that age (c.f. Acts 5:34). Then there is the example of Luke, who was not only a doctor but a commensurate historian according to the standards of his day.12 Yes, simple fishermen like Peter, James, and John were attracted to Christianity, but note that all three were at least literate, by no means a widespread characteristic of the times. There are other examples, like Apollos, a demonstrably learned man (Acts 18:24–28), Roman military officers (Mat 8:5–13; Acts 10:1, 22), influential Roman civic leaders (Acts 13:7–12), Greek civic leaders (Acts 17:34), Jewish civic leaders (Mat 27:57–59; Mark 15:43–46; Acts 18:7; 1 Cor 1:1), and Jewish business people (Acts 16:14), all of whom came into early Christianity.
Why do the Jews have higher IQs on average? His answer was that it was the Europeans pushing the Jews out of farm labour and into occupations like money-changing, coupled with that culture’s emphasis on literary skills (p. 210). It would only take, he claims, a slight percentage difference in the average procreativity of the slightly smarter Jews over the course of centuries to generate the slight difference in IQ in them when compared to other cultures (but see ref. 10). But his notions of the scale and power of natural selection are both rudimentary and sophomoric. It is clear he has had no formal training in population genetics.
He gives examples where luck, environment, and culture have all led to the success or failure of a people group. Where is the genetics in this? He also rails against Jared Diamond’s thesis, in his famous Guns, Germs and Steel, that geography plays a significant role in human success and that there are no genetic differences among people groups that contribute to the success of any one people. Yet, he effectively outlines Diamond’s main points in his arguments in the final chapter (p. 236).
Speaking of a dramatic drop in violence and a commensurate rise in literacy among the English, he says, “That a profound change in human social behavior should evolve in just a few centuries may seem surprising, but it is perfectly possible” (p. 160). He then cites for support the work on the domestication of the fox, an example of artificial truncation selection. This is highly suspect, as this has nothing to do with the probability selection that is expected to occur in natural populations. He also admits a few pages later that “the genes underlying violence are for the most part unknown” (p. 172).
Overall, I found Wade’s book less than what I expected from such a well-placed individual. If this is his best case, I conclude there is not much to support the idea that the genetic differences among people groups are significant in terms of outcomes.