Reviewing A Troublesome Inheritance

A Troublesome Inheritance: Genes, Race and Human History by Nicholas Wade. Penguin Press, 288 pages, published on May 6th.

By Emily Willoughby and Jonathan Kane

Nicholas Wade's new book on race and genetics, aptly titled A Troublesome Inheritance, has been generating a lot of hubbub since its release around a week ago. It's occupying the #1 slot for every category in which it's listed at Amazon.com, despite having fairly average reviews by Amazon standards. And it's certainly not the first book to discuss most of the concepts it explores, either. So why so much fuss over another book on race?

The answer comes from the unusual thesis the book is attempting to support. A Troublesome Inheritance is essentially divided into two parts, each of which advances a different proposition. The first part serves as an explanation of how advances in genetics have overturned the long-standing idea that the concept of race is biologically meaningless. Wade argues that when humans are divided into groups based on genetic distance, the groups more or less correspond to our traditional concept of race: Europeans tend to cluster with other Europeans, East Asians with East Asians, and so on with Sub-Saharan Africans, Oceanians, and Native Americans. He presents data that in addition to genes that affect traits such as skin color, human races also differ in the distribution of genes that more significantly impact people's lives, such as lactase persistence (the ability to digest milk as adults), or a gene called MAO-A that increases the likelihood of aggression. In the second part of the book, Wade goes beyond the evidence for simple physical diversity in racial groupings. Here, he advances the idea that these differences extend to behavior, and that these behavioral differences underlie historical disparities in human societies and cultures. These evolutionary variations, he claims, could explain things like why the Industrial Revolution occurred where and when it did, and why Ashkenazi Jews have been vastly overrepresented among Nobel Prize winners. This thesis that "human evolution has been recent, copious and regional" is the driving thrust of the book, and is one of the factors that has contributed to its criticism.

Most of these ideas have been around for several years, and are well-known in their respective fields. The idea that racial categories are both useful and biologically meaningful was presented in What's the Use of Race? published by MIT in 2010, and the idea that evolutionary differences between human groups have contributed to cultural differences today was explored by the 2009 book The 10,000 Year Explosion. Both of these books were well-received and not especially controversial, but they both also are "niche" books that did not receive a lot of publicity. A lot of the controversy surrounding Wade’s book is not so much related to its ideas themselves, but to the fact that they are being presented in a widely-publicized book by a well-known author.

I'll be honest up front: I found the book disappointing, mostly because I wanted to see a book like this that was much more nuanced, much more carefully researched, and much more elegantly written. This is not the book I was looking for. Nicholas Wade is a science writer for the New York Times, and while he's certainly not a bad writer, he clearly doesn't have the technical expertise that such a lofty thesis would demand. Some reviewers, like Gregory Cochran, have pointed out that Wade makes it disappointingly obvious that he's not a geneticist, and that the book - based largely around an understanding of genetics - suffers as a result. But that's really selling Wade short: he's also not a psychologist, a biologist, or a historian. It shows.

The book has a number of errors, some of which are small enough that they don't have much effect on the overall theses. One example comes from Chapter 1 (which he later repeats near the end of the book) where he claims that "no genetic variants that enhance intelligence have yet been found", cited to the Chabris 2012 study. Genetics has advanced a great deal in two years, and Wade was evidently unaware of the myriad studies done in the interim that have managed to detect more signal amongst the noise with respect to alleles that contribute to intelligence variance. Our previous post tackles a few of these, but there are at least several more (some of which are in the works). Being aware of this research would have furthered Wade's thesis rather than contradicting it, but I think this unawareness of better, newer research can be viewed as a surrogate for the general level of scholarship of the entire book. There's no reason to assume the book isn't peppered with similar errors in areas of research I'm not as familiar with. In many cases, this obfuscation may be a result of unnecessary attempts at oversimplifying complex ideas.

The biggest issue isn't the minutiae of out-of-date studies and slight misstatement of facts, though. It's that much of the support for Wade's second thesis, about how group differences have impacted society, rests on convenient just-so stories and speculation rather than on hard data, because genetics has not yet progressed to the point that it can directly support them. Worse, Wade often presents data without citing a source, which makes it unnecessarily difficult to tell when he's stating facts and when he's invoking speculation. When writing about a such a controversial topic, clearly supporting novel ideas with data is of paramount importance, but in this case, a lot of the data Wade would need simply doesn't exist yet.

Don't get me wrong, A Troublesome Inheritance isn't all bad. I think part of my own frustration at this book stems from having just recently read Steven Pinker's The Better Angels of Our Nature (which, incidentally, is misrepresented by Wade in A Troublesome Inheritance). Better Angels tackles a lot of the same issues as Wade's book, but where Wade seeks to explain the decline of violence and rise of reason in human societies with chiefly genes alone, Pinker approaches the issue from a much more comprehensive and logical perspective that's rooted both in human nature and complex cultural change. So reading this now is a bit like trying to chase a filet mignon with a McDonald's hamburger and then trying to find something nice to say about the hamburger. The most I can come up with is "Well, it’s beef... and I like beef..."

I think the world still needs more books like Wade's, simply because some of its ideas are important and haven't been presented to the public before. For example, this is the first major book I'm aware of that discusses the 2011 study showing that Stephen Jay Gould was wrong when he claimed in The Mismeasure of Man that Samuel George Morton had fudged his measurement of skulls, and that all of the errors had in fact been Gould's. It can take a long time for society to recognize errors like this that have become culturally entrenched, but perhaps Wade's book will help to change this. Wade also points out that it's a significant problem how scientists can't examine behavioral differences between groups without being accused of racism, and that these politically-motivated sentiments have no place in science. This has been said before, but bears repeating. For all its flaws, my hope is that this book will help in some small way to dispel the myth that race has no basis in biology, and also the even more pervasive myth that there is no legitimate reason to explore group differences, genes and behavior. Unfortunately, disentangling the rat's nest of culture and genetics is going to take more than a slim speculative volume by a science writer.

It's important for the public to understand both the areas where this book is strong, and where its shortcomings are. There’s no reason to doubt that its flaws will become well-understood, because there are a number of reasonable critiques of the book that point out the areas where its speculation isn't well-supported. In addition to the aforementioned review by Gregory Cochran, two other examples are this review by statistician Andrew Gelman, and this review by Anthony Daniels (who may or may not have played C-3PO in Star Wars). Note that the criticism in these reviews is focused on the second half of the book, about how evolutionary differences between human groups influenced human history. Far more concerning is that the public might not learn anything even from the book's better-supported first half, because of a small group of reviewers who seem to wish for the book to be discredited entirely, and are using arguments at least as dubious as anything in the book itself.

There are several reviewers who do this, but I'm going to focus on one in particular, both because he exemplifies all of what future reviewers of this book should be careful to avoid, and because he’s someone who should know better. It's the anthropologist Jonathan Marks, who has reviewed the book twice: once on May 12th for In These Times, and a second time on May 14th for the American Anthropological Association. In these reviews, Marks claims that both theses of the book are factually wrong - that biological differences between races not only haven't influenced human history, but that they have no effects at all. An equally important focus of his reviews is the idea that the book is morally wrong, because Wade is presenting ideas that have historically been misused to support injustice. Marks calls Wade's ideas "a slightly new spin on a set of old prejudices" (this is a phrase that appears word-for-word in both reviews), and "outmoded, racist ideologies masquerading as science."
UPDATE: Marks has also reviewed this book a third time on May 31st.  His third review says basically the same things as his first two.

Marks has a conflict of interest reviewing this book. He's the author of several pop-science anthropology books presenting the perspective that race has no basis in biology, it's a perspective he also presents in a course he teaches called "Anthropology and Race", and his devotion to attacking Wade’s book may be partly because he views its ideas as a threat to his own professional reputation. You might expect a rival scientist to only focus on providing a factual rebuttal, but this aspect of Marks' response actually is the most common, ever-present response to ideas such as Wade's: that the effects of differences between races should never be researched or discussed, because of how these ideas have been abused in the past. Before any more reviewers repeat this meme, I think it deserves further examination.

The science blogger HBD Chick makes an important point about this idea. Genocide, racism, and xenophobia all predate human history, and it's foolish to think that beliefs about biological differences between races are to blame for these millennia-old practices. The Nazis misused race differences as an excuse for their genocide of Jews, but crimes of similar scale have been committed without any need to invoke this excuse, such as Stalin's mass starvation of Ukrainians in the 1930s. The way to prevent crimes like these isn't by preventing discussion about race and genetics, but by encouraging the universal recognition of human rights, as well as recognition of the fact that these rights don't require a basis in biology. This is one reason why Hitler’s misuse of an idea is not a good reason to avoid discussing it in the present, but there's also a second reason, which is best demonstrated using a comparison.

Not many people are aware of this anymore, but the first country to demonstrate a link between smoking and lung cancer was Nazi Germany. This was not a case of research being conducted by good scientists, and being subsequently misused by racists. One of the purposes of this research, at the time when it was being conducted, was to support the belief that cancer was somehow linked to racial impurity, and to further the goal of creating a cancer-free and racially pure utopia. At this point in history, Nazi Germany was the only country researching the link between smoking and lung cancer, so as a scientific hypothesis this idea was inseparable from the Nazis' racial ideology. The Nazis' research in this area is summarized in Richard Proctor's book The Nazi War on Cancer.

Scientists in the United States and England eventually reproduced this research in the 1950s, despite the resulting moral outrage at their attempting to prove an idea originally used to support the Holocaust. The historical connection between anti-smoking research and Nazism continued to be an objection to public health measures in this area until the 1990s, as described in this paper. As the connection between smoking and lung cancer has entered the scientific mainstream, the United States seems to be slowly forgetting the racist roots of this idea, although they haven't been forgotten in Germany.

The moral objections in Marks' review are objections that could have been made, and in some cases were made, to publicizing the connection between smoking and lung cancer in the second half of the twentieth century. In the case of causes of lung cancer, I think the world is very fortunate that these criticisms were ignored. I'm Jewish by ancestry on my mother's side, and my mother's parents had relatives who were killed by the Nazis, but they also had at least one sibling who died from lung cancer as a result of smoking. If these objections had succeeded at suppressing knowledge about smoking and lung cancer, it would not have saved anyone's life, but would have caused there to be many more people whose lifespans were shortened by smoking due to being unaware of its health risks.

Although it's less obvious how public health benefits from research about the effects of race differences, the same principle applies there also. This article from the New York Times describes how determining the best possible treatment for patients often requires including their race as a factor. Reactions to drugs do not line up perfectly with racial divisions, but there is enough of a correlation that this can sometimes be a decisive factor in determining the correct dosage, especially since a standard dose for one patient can be a lethal overdose for another. Note that this article is from 2002. In the time since then this practice had gradually declined, mostly due to the belief that it's always wrong to let one's actions towards a person be influenced by their race. But as is mentioned in that article, it has been documented that this approach was able to save lives, and these lives are not saved when this practice is abandoned.

In a paper published in 2005, Marks has denounced this practice. His argument is that since every anthropologist knows that racial categories don't mean anything in biology, race could not possibly be useful in a biomedical context, and that using it there also is immoral because race has historically been used to justify things like segregation. The claim that race could not possibly be useful in medicine is not typically convincing to doctors who have experience showing otherwise, but it's effective for creating a political climate in which using this information to improve care for one's patients is risky to a doctor's career. In some cases, doctors who listen to Marks' advice would have to ignore the instructions packaged with the drugs they're prescribing. One example is the warning included with the drug Crestor (rosuvastatin): "People of Asian descent may absorb rosuvastatin at a higher rate than other people. Make sure your doctor knows if you are Asian. You may need a lower than normal starting dose."

There are legitimate arguments that can be made against the use of racial categories in biomedicine, such as that personalized genomics will eventually make it possible to determine a patient's sensitivity to drugs far more precisely, so that the use of race in biomedicine will eventually become superfluous. But that isn't the argument Marks makes. In both his 2005 paper and his reviews of Wade's book, he is arguing that ideas with a racist history should simply not be considered, which in both content and effect is essentially identical to the argument which was made against research on the health risks of smoking. He's also arguing that people who repeat these ideas are themselves guilty of racism, but if he intends to denounce A Troublesome Inheritance by attacking Wade's motives, he should be prepared for his own to be questioned as well.

I don't believe it's possible for someone who's written on this topic as extensively as Marks to be completely unaware of the basic statistics about it, or of the instructions included with drugs such as Crestor. Ignorance is not an excuse, but he's evidently decided it's better for this data to be disregarded, for reasons related to either morality or self-interest. If Marks can ensure that research on the effects of race differences remains forever taboo, he can no doubt preserve the popularity of his own books and of the college course he teaches. He's also Caucasian, and the proper drug doses for Caucasians are always widely-known, so it's no loss to him if doctors sometimes fail to prescribe effective dosages to minorities. But I would argue that it's immoral for him to prioritize his career over minorities receiving proper medical care. And... hey, isn't there a word for that sort of attitude?