Genetic basis for race

It is obvious that humans vary tremendously in physical appearance. Other biological features such as blood type and enzyme production are equally diverse. Many people, if asked, would probably claim that these differences are profound and consistent enough to allow for categorizing humans into various distinct racial categories. A “race” might be defined as an isolated population within a species that has little or no gene flow with other members of that species. After a substantial period of time, this subgroup may take on numerous physical characteristics that are slightly different from the others of the species.

Although there might be some human populations that could be called races, the way that the term is commonly used is simply not scientifically justifiable and has little value. In short, for all practical purposes, “races” do not exist as a natural biological category in the way that “species” do. The “races” of human beings are all of the same species and, biologically, are essentially identical. To be sure, as many people can personally attest, races do exist as social categories (discrimination being just one manifestation). However, these social categories are no more real or natural than any other arbitrary cultural construct (such as having to wear ties to work in an office).

Historical Racial Typologies and Explanations

The most common way of dividing the world racially has been the tripartite “White” (Caucasian), “Black” (Negroid), and “Asian” (Mongoloid), using the vernacular and pseudoscientific terms respectively. Since the days of naturalist Charles Darwin, who developed the theory of evolution, natural selection has often been the primary explanatory device to account for the great physical diversity seen in the world’s people. For example, the tall and thin East African Dinka have bodies that radiate heat, an obvious advantage in an equatorial environment. People living in the Andes or near the Arctic Circle are short and squat for the opposite reason: Their bodies have less surface area to radiate heat, a useful trait for living in the extreme cold. However, such explanations are not completely compelling, as not everyone living in a warm climate is lean and tall, nor are all peoples in cold climates heavier and small. Likewise, consider skin pigmentation as an adaption to varying exposures to sunlight. Although darker skins are believed to protect against sunburn, and white skin allows for easier absorption of necessary ultraviolet light in places with long winters, some of the darkest-skinned people in the world are the Tasmanians, who lived in an area receiving only moderate sunlight. Attributes such as eye color and hair color and texture seem to have no genetic adaptive advantage whatsoever.

Racial Criteria, and Some “New” Races

If adaptive or environmental explanations of racial variation are lacking, so are the definitions of race. There are thousands of ways to define a race. In recent times in Western countries, skin color has been the primary way to classify people; however, this has not always been the case, nor is this the only characteristic that can be used to separate people. For example, if classification were made by the epicanthic fold (which covers the inner edge of the eyes and is typically found among people in East Asian countries), Japanese, Chinese, Koreans, and the Kung San of Africa would fall into the same “race.” The former emperor of Japan Akihito and former South African leader Nelson Mandela share this feature. If blood typology were used, hundreds of different races could be constructed. For instance, Scots, central Africans, and Australian aboriginals could be placed together in the same biological (racial) category, because about 75 percent of their populations have O-type blood. Using the presence or absence of the sickle-shaped red blood cell, most Africans and African Americans would be placed in the same race along with Greeks and Italians. If dentition were used, East Asians, Native Americans, and Swedes could form a race, as they all share incisors (eyeteeth) that are “scooped out” in the back.

Problems with Definitions

Inherent in every definition of race are at least four major problems involving clines, covariation, randomness, and arbitrary or self-definitions. Although clines, or gradations, of skin color and other traits exist, people do not fall into clear-cut, distinct categories. Even if skin color, the most common measure, is used as the primary racial criteria, no clear or natural separations exist between peoples. There are groups of light-skinned Black people and populations of swarthy White people; people exist in every skin shade from light to dark.

Traits do not covary. If races were indeed real categories, different features should vary together. For example, all members of a particular race (White, Black, or Asian) should have the same hair texture, facial features, blood type, eye and hair color, and other inheritable characteristics. However, among the world’s peoples are populations of blond-haired “lack” Australian aboriginals, “White” people who typically have flat “Asian” noses, and “Asians” with textured hair. The features used to classify people according to “race” do not always occur as sets, which would be the case if true biological categories existed. In addition, biological anthropologists have long known that, using measurements of almost any physical criteria, just as much random variation exists within a so-called racial category as between “races.” This calls into question the notion of race as a useful, or even valid, category.

Racial designations—especially legal ones—are basically arbitrary. One Jewish grandparent was enough to make an individual a Jewish person in Nazi Germany. In many southern states in the United States, if a person had any Black ancestors, according to the one-drop rule, that individual was Black, regardless of appearance. In the 1990s, because of increasing diversity and interracial marriage in the American population, the question of racial designations became more complex. What should a person with a “White” grandfather, “Black” grandmother, and Asian mother be called? Often, this is something that people decide for themselves. Professional golfer Tiger Woods, for example, says that when filling out forms, he checks every racial category that applies to make certain all of his ancestries are represented. The U.S. government is also aware of the arbitrariness of the racial and ethnic categories it uses to classify people, including those used in the census. For example, in 1997, federal agencies debated whether native Hawaiians, when filling out census questionnaires, should remain grouped with Asians and Pacific Islanders or be placed in the category with Alaskans and Native Americans. The 2000 census included one category for Asians and another group for native Hawaiians and Pacific Islanders.

Between 50,000 and 100,000 pairs of genes are required to make a human being, and perhaps 75 percent of these are the same for everyone in the world. Only a small fraction of these genes—perhaps less than a dozen pairs—might account for skin pigmentation. The genes of White and Black Americans are probably about 99.9 percent alike. There is simply no way to put five million Americans into three, six, or even a hundred racial categories that makes biological sense or has any scientific validity.

Bibliography

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Gould, Stephen Jay. The Mismeasure of Man. Rev. and expanded ed. New York: Norton, 1996.

Herrnstein, Richard, and Charles Murray. The Bell Curve. New York: Free, 1994.

Jacoby, Russell, and Naomi Glauberman. The Bell Curve Debate. New York: Random, 1995.

Sussman, Robert Wald. The Myth of Race: The Troubling Persistence of an Unscientific Idea. Harvard University Press, 2016.