Why “Race” Isn’t Biological

Patrick Appel —  May 20 2014 @ 1:38pm
by Patrick Appel

This speech by Charles Mills, which we’ve posted before, does an excellent job explaining the social construction of race:

Nicholas Wade’s new book on race and genetics, which takes the biological basis of race as a given, provides no consistent definition for “race.” During his debate with Wade, anthropologist Agustín Fuentes pointed out that “Wade uses cluster, population, group, race, sub-race, ethnicity in a range of ways with few concrete definitions, and occasionally interchangeably throughout the book.” In a response to Wade’s book, Fuertes explains how A Troublesome Inheritance gets race so wrong:

The originators of the computer program most often used to support the argument that humans divide into the continental genetic clusters (which Wade says are “races”) comment that their model (called structure) is not well-suited to data shaped by restricted gene flow with isolation by distance (as human genetic variation data on large scales are). They warn that if one does try to apply this model to those data, the inferred value of K (how many clusters emerge) can be rather arbitrary. For example, one article Wade cites shows not three, not five, not seven but 14 clusters, six of which are in Africa alone.

So when Wade states in chapter 5 of his book, “It might be reasonable to elevate the Indian and Middle Eastern groups to the level of major races, making seven in all,” he notices a problem: “But then, many more subpopulations could be declared races.” But he has a solution: “[T]o keep things simple, the 5-race continent based scheme seems the most practical for most purposes.”

Sure, it is practical if your purpose is to maintain the myth that black, white and Asian are really separable biological groups. But if your goal is to accurately reflect what we know about human biological variation, then no, it is a really not practical at all; in fact, it is flat-out wrong. What we know about human genetic variation does not support dividing humans into three or five or seven “races.”

Other writers who argue that race is biological aren’t as sloppy as Wade. And, even though I do not believe that defining race biologically is correct, it’s best to engage with the strongest arguments of those who disagree. For starters, here is part of a 2012 post by Jerry Coyne that defends defining human races biologically:

What are races?

In my own field of evolutionary biology, races of animals (also called “subspecies” or “ecotypes”) are morphologically distinguishable populations that live in allopatry (i.e. are geographically separated).  There is no firm criterion on how much morphological difference it takes to delimit a race.  Races of mice, for example, are described solely on the basis of difference in coat color, which could involve only one or two genes.

Under that criterion, are there human races?

Yes.  As we all know, there are morphologically different groups of people who live in different areas, though those differences are blurring due to recent innovations in transportation that have led to more admixture between human groups.

Coyne, in the midst of a scathing review of Wade’s book, writes that “Wade’s discussion of genetically differentiated subgroups, whether or not you want to call them ‘races’—is not too bad.” H. Allen Orr, who tears Wade’s book to shreds, likewise defends a genetic definition of race:

The central fact is that genetic differences among human beings who derive from different continents are statistical. Geneticists might find that a variant of a given gene is found in 79 percent of Europeans but in only, say, 58 percent of East Asians. Only rarely do all Europeans carry a genetic variant that does not appear in all East Asians. But across our vast genomes, these statistical differences add up, and geneticists have little difficulty concluding that one person’s genome looks European and another person’s looks East Asian. To put the conclusion more technically, the genomes of various human beings fall into several reasonably well-defined clusters when analyzed statistically, and these clusters generally correspond to continent of origin. In this statistical sense, races are real.

Coyne adds:

This is what I also claimed, and of course got slammed by the race-denialists who are motivated largely by politics.  To a biologist, races are simply genetically differentiated populations, and human populations are genetically differentiated.  Although it’s a subjective exercise to say how many races there are, human genetic differentiation seems to cluster largely by continent, as you’d expect if that differentiation evolved in allopatry (geographic isolation).

Relatedly, Razib Khan argues that “the modern American consensus that race is a social construct is true but trivial”:

It’s true because a de facto race such as “Latinos/Hispanics” were created in the 1960s by the American government and elite for purposes of implementing public policies such as affirmative action. Obviously this is a classic case of a social construct, as the quasi-racial category is based upon social, not biological, factors (Latinos/Hispanic can explicitly be of any race, though implicitly it’s transformed into a non-white class in the United States). A group like “black Americans” ranges from people with considerably less than 50% African ancestry to more than 90% African ancestry (though almost always black Americans who are not immigrants from Africa or first generation offspring of those immigrants have some segments of European ancestry). The problem is that people move from this non-controversial point, that some racial categories are social constructs, to the assertion that all racial categories are social constructs, and that phylogenetic clustering of human populations is irrelevant or impossible. It is not irrelevant, or impossible. Human populations vary, and that variation matters. Human populations have specific historical backgrounds, and phylogenetics can capture that history through methods of inference.

I disagree with Khan calling “phylogenetic clustering of human populations” races, but Razib is far more intelligible here than Wade is in most of his book. Nevertheless, the biological definitions of race outlined above are problematic because they are not the same as the social definitions of race. There is significant overlap between the biological and social definitions but defining “race” two ways only confuses matters. In an interview, Wade offers an explanation for why he uses the term “race” as he does:

It seems that the problem might be, as you said, that there is so much historical baggage associated with the term race. Is there a way to get around that? Do we just need a different term than race to talk about these genetic differences?

I’m not sure how that will play out. The geneticists, if you read their papers, have long been using code words. They sort of dropped the term “race” about 1980 or earlier, and instead you see code words like “population” or “population structure.” Now that they’re able to define race in genetic terms they tend to use other words, like “continental groups” or “continent of origin,” which does, indeed, correspond to the everyday conception of race. When I’m writing I prefer to use the word race because that’s the word that everyone understands. It’s a word with baggage, but it’s not necessarily a malign word. It all depends on the context in which it’s used, I guess.

Wade says that “everyone understands” the word race. But what everyone understands are the social definitions of race: White, Black, Latino, Asian, Native American, Samoan, and so on. Wade dismisses geneticists who use terms like “population structure,” “population stratification,” “ancestry” and “ancestry informative markers.” But those terms are useful when discussing genetics because they allow for far more complexity and specificity than our social definitions of race do.

Obviously, skin color and the other physical characteristics society uses to categorize individuals racially are biological. But skin color and other physical traits are not the same as race. And, as Khan noted recently, one “of the ironies of traits which we use to differentiate populations, such as skin color and facial features, is that these might actually have relatively shallow time depth within a given lineage.” So prioritizing skin color above all other ancestry informative markers finds little basis is biology. In a 2012 post, Fuentes argued against a biological understanding of race for related reasons:

Even something thought to be so ubiquitous as skin color works only in a limited way as dark or light skin tells us only about a human’s amount of ancestry relative to the equator, not anything about the specific population or part of the planet they might be descended from.

There is not a single biological element unique to any of the groups we call white, black, Asian, Latino, etc. In fact, no matter how hard people try, there has never been a successful scientific way to justify any racial classification, in biology. This is not to say that humans don’t vary biologically, we do, a lot. But rather that the variation is not racially distributed.

Alfred W. Clark, a strong defender of Wade’s book, has a useful round-up of commentary on A Troublesome Inheritance. In it, he dismisses Fuentes by arguing that he is suffering from a “slightly more sophisticated version of Lewontin’s Fallacy.” What is Lewontin’s Fallacy? In a 2005 NYT article arguing that race is biological, Armand Marie Leroi explained it:

The dominance of the social construct theory can be traced to a 1972 article by Dr. Richard Lewontin, a Harvard geneticist, who wrote that most human genetic variation can be found within any given “race.” If one looked at genes rather than faces, he claimed, the difference between an African and a European would be scarcely greater than the difference between any two Europeans. A few years later he wrote that the continued popularity of race as an idea was an “indication of the power of socioeconomically based ideology over the supposed objectivity of knowledge.” Most scientists are thoughtful, liberal-minded and socially aware people. It was just what they wanted to hear.

Three decades later, it seems that Dr. Lewontin’s facts were correct, and have been abundantly confirmed by ever better techniques of detecting genetic variety. His reasoning, however, was wrong. His error was an elementary one, but such was the appeal of his argument that it was only a couple of years ago that a Cambridge University statistician, A. W. F. Edwards, put his finger on it.

The error is easily illustrated. If one were asked to judge the ancestry of 100 New Yorkers, one could look at the color of their skin. That would do much to single out the Europeans, but little to distinguish the Senegalese from the Solomon Islanders. The same is true for any other feature of our bodies. The shapes of our eyes, noses and skulls; the color of our eyes and our hair; the heaviness, height and hairiness of our bodies are all, individually, poor guides to ancestry.

But this is not true when the features are taken together. Certain skin colors tend to go with certain kinds of eyes, noses, skulls and bodies. When we glance at a stranger’s face we use those associations to infer what continent, or even what country, he or his ancestors came from – and we usually get it right. To put it more abstractly, human physical variation is correlated; and correlations contain information.

Genetic variants that aren’t written on our faces, but that can be detected only in the genome, show similar correlations. It is these correlations that Dr. Lewontin seems to have ignored. In essence, he looked at one gene at a time and failed to see races. But if many – a few hundred – variable genes are considered simultaneously, then it is very easy to do so.

But this still fails to prove that races are biological. Calling these populations “races” is a semantic rather than a scientific decision. Wikipedia provides useful context on this front:

Philosophers Jonathan Kaplan and Rasmus Winther have argued that while Edwards’s argument is correct it does not invalidate Lewontin’s original argument, because racial groups being genetically distinct on average does not mean that racial groups are the most basic biological divisions of the world’s population. Nor does it mean that races are not social constructs as is the prevailing view among anthropologists and social scientists, because the particular genetic differences that correspond to races only become salient when racial categories take on social importance. From this sociological perspective, Edwards and Lewontin are therefore both correct.[13][14][15]

Similarly, biological anthropologist Jonathan Marks agrees with Edwards that correlations between geographical areas and genetics obviously exist in human populations, but goes on to note that “What is unclear is what this has to do with ‘race’ as that term has been used through much in the twentieth century – the mere fact that we can find groups to be different and can reliably allot people to them is trivial. Again, the point of the theory of race was to discover large clusters of people that are principally homogeneous within and heterogeneous between, contrasting groups. Lewontin’s analysis shows that such groups do not exist in the human species, and Edwards’ critique does not contradict that interpretation.”[6]