When Donald Trump invoked genetics at a campaign rally in Minnesota in September 2020, commentators were quick to connect his language to the eugenics and Nazi science of the early 20th century. “You have good genes, you know that, right?” Trump asked his nearly all-white audience. “You have good genes. A lot of it is about the genes, isn’t it, don’t you believe?” The implication was that—by dint of its race—his crowd was genetically distinct from, and superior to, the Black and brown immigrants that Trump consistently disparaged and targeted with his administration’s policies.
This perspective, explicitly endorsed by some on the political far right today, was once the mainstream scientific view. Today, however, most scientists don’t take the idea of biological races seriously—partly thanks to Richard Lewontin, a Harvard University evolutionary biologist who died in July at age 92. Lewontin made his name in the 1960s, when he demonstrated, using populations of wild fruit flies, that individuals of a species are far more genetically diverse than scientists had previously imagined.
In 1972, Lewontin took his interest in genetic diversity in an explicitly political direction when he published a paper demonstrating that only about 6 percent of human genetic variation exists between conventionally defined racial groups; the rest can be found within those groups. By surveying how alternative versions of particular blood proteins—coded for by subtle variations of the same genes—were distributed throughout the human population, he was able to figure out just how much genetic overlap exists among racial groups.
If, for example, all white people had turned out to have type A blood and all Black people type B, the idea of genetically distinct racial groups would have been partly validated. But if half of people in both groups had type A blood and half had type B, all of the genetic variation would exist within the groups, not between them. Reality, Lewontin found, was far closer to the latter scenario. More recent experiments surveying a much wider variety of genes have validated Lewontin’s findings.
He concluded the 1972 paper with a statement that would look shockingly political in the scientific journals of today. “Human racial classification is of no social value and is positively destructive of social and human relations,” he wrote. “Since such racial classification is now seen to be of virtually no genetic or taxonomic significance either, no justification can be offered for its continuance.” The paper was seminal—according to Google Scholar, it has been cited more than 3,000 times—and constitutes a major pillar of support for the aphorism “race is a social construct.”
“The idea that there was more variation within a group than across groups is an old one. That had been there for decades,” says Jonathan Marks, professor of anthropology at the University of North Carolina at Charlotte. “What Lewontin did was put numbers on it. And that was very powerful.”
Since the 1970s, new technologies have changed the landscape of genetics markedly: Large-scale genomic studies have shifted the way that scientists understand the relationship between genes and behavior. “Lewontin was prescient in anticipating that, with the major public investment in genomics, genetics would take a primary seat in terms of trying to explain disease—as well as, increasingly so, social behavioral traits,” says Sandra Lee, professor of medical humanities and ethics at Columbia University. As the power and sophistication of genetic technologies continue to grow, Lewontin’s work remains remarkably current.
One of Lewontin’s great bugbears was his Harvard colleague E. O. Wilson, who held strong and influential opinions about the role of genetics in determining social behavior in animals and humans alike. With his 1975 book Sociobiology: The New Synthesis, Wilson popularized the idea that behaviors ranging from altruism to aggression to sexual mores can best be explained by reference to evolutionary pressures. Lewontin believed that Wilson unjustifiably assumed—largely on the basis of animal research—that many human behaviors and characteristics, from creativity to conformity, must have been selected for during the evolutionary history of the species. Lewontin argued that this idea represented just one more resurgence of the regressive conviction that biology was destiny, which, he said, had been used to shore up social hierarchies for centuries.
Lewontin criticized Wilson so sharply that Wilson would refuse to enter the elevator in the Harvard’s Museum of Comparative Zoology when Lewontin was already in it, according to Steven Rose, a professor emeritus of neurobiology at the Open University in London who fought genetic determinism alongside Lewontin. “Dick certainly collected his muster of enemies,” Rose says.
(As of press time, Wilson had not responded to emailed requests for an interview.)
To Lewontin, scientists who focused solely on genetics ignored not only the profound role that environment plays in shaping behavior but also the complexity of the interactions among genes and the environment. In a world in which every child received an identical education and experienced an identical home situation, for example, genes would probably play a major role in explaining differences in IQ scores. But in the real world, where children attend schools of vastly different qualities, come from a rich variety of cultures, and experience varying degrees of challenge in their home lives, environment almost certainly plays a much larger role.
Lewontin “caution[ed] against a rush to find a genetic explanation at the expense of understanding genes as only one part of an explanatory model,” Lee says. Today, when scientists can use genome-wide association studies to detect minuscule associations between genes and particular traits or behaviors—IQ, depression, criminality—Lee says this caution is particularly essential. A statistical association between a gene and a trait does not imply that the gene caused that trait: Some genes may be correlated with factors like socioeconomic status or place of residence that could play a far more important role. For example, a gene that appears more commonly in a particular region of the world might be associated with speaking a particular language, but the gene certainly does not cause an individual to start speaking that language.
Yet in its attachment to genetics, biology has not entirely left behind the idea of race, especially when it comes to medicine. In 1993, recognizing the substantial health disparities that exist in the US between people of different racial groups, the government required that all National Institutes of Health–funded clinical research include minorities as subjects. Though well intentioned, Lee says, this directive also came with risks. Differences in, say, the average rates of heart disease or diabetes between white and Black people could be explained with reference to social and environmental factors—or they could be attributed to genetic differences between the races. “In this call for more diversity, there’s a real responsibility to ensure that that race does not become the primary dimension by which we understand difference,” Lee says. “We always stop at race instead of really trying to understand race as a social process.”
Race, construed as a biological variable, already factors into the prescription decisions that doctors make—at least for one medication. In 2005, the US Food and Drug Administration approved the drug BiDil, a treatment for heart failure, specifically for use in Black patients—based on results from a trial that had enrolled only Black individuals. The approval sparked a major controversy: Numerous academics spoke out against the idea of racially specific drugs, given that race is not a coherent biological category. Today the drug is still specifically approved for Black users, although doctors can prescribe it off-label to others.
Granted, some diseases caused by single genes are much more common in particular ethnic groups—Tay-Sachs disease in Ashkenazi Jews or sickle cell disease in people of African descent, for example. But such associations don’t imply that race is always an important factor in the genetics of health, Marks says. Statistically speaking, “if you’re Black, you have a lot more reason to worry about your neighborhood’s health risks than about whether you have sickle cell anemia,” he says, referring to factors like air quality and access to nutritious food.
Outside of the health care domain, Americans are generally hesitant to associate race with genetics, at least publicly. Although far-right politicians might openly endorse links among race, genetics, and social success, “most people understand that they’re not supposed to say that,” says Jennifer Hochschild, professor of government and African and African American studies at Harvard University. However, she says, “many scholars think there are probably more people who agree with some version of genetic determinism than are willing to say so.” One 2019 study found that around one in five non-Black Americans believe that genetics partially explains income inequality between Black people and white people. But to get around “social desirability bias,” or respondents only saying what they think others want them to say, the researchers cleverly avoided asking the participants to make statements themselves about race—instead, they asked them to report how many statements on a given list they agreed with.
Presumably, this 1-in-5 figure would be far lower among scientists, who largely recognize the enormous role each person’s environment plays in determining the contours of the social world. But “that view has not filtered through to the general public, who still talk quite contentedly about ‘genes for this’ and ‘genes for that,” Rose says. “Simplicity is much easier than complexity to deal with.”
These days, there’s a new, major source of messaging about the relationship between genes and race: genetic ancestry testing. Companies like 23andMe and Ancestry purport to tell clients about the ethnicities that make up their backgrounds, down to the percentage point. But inferring where someone’s great-great-great-great-great-grandparents lived is a far less precise process than marketing materials suggest. “The thing I like to say about genetic ancestry testing is that it’s about as reliable as a good look in the mirror,” Marks says. “And [it’s] a very expensive mirror.” Nevertheless, as of 2019, 26 million people had sent their saliva to be tested by these companies.
Lewontin was notable for engaging directly with the general public—he wrote a regular column in the New York Review of Books, and much of his writing is accessible to people with little or no scientific background. He wrote broadly on the intersections between science and society, covering topics from genetically-modified foods to biological conceptions of gender to sex research. “He was a scientist that felt that it was a responsibility to communicate with the public,” Lee says.
And today, some scientists do follow in his footsteps: When the former New York Times journalist Nicholas Wade published a book linking genes, race, and IQ in 2014, nearly 140 geneticists cosigned a letter to the editor objecting to Wade’s misuse of genetics to defend the idea that human racial groups evolved different abilities after some migrated from Africa to other parts of the world. “That’s progress,” Marks says. “That is the genetics community taking a stand against the socially irresponsible invocation of the field of genetics, and I think it was Lewontin who really put that on the table.”
But not all scientists will be willing to take the stands that Lewontin did. Unlike many scientists, in the ’70s and today, Lewontin was open about his politics—he was an avowed Marxist, and his political commitments motivated him to address the racism, sexism, and imperialism that he saw in science. His openness may have worked to his disadvantage—Wilson, for example, dismissed Lewontin’s criticisms of sociobiology on the basis of his politics. “Lewontin was always very upfront about his ideology,” Marks says. “Other geneticists would go, ‘Oh, look, he has an ideology. That’s a problem.’ They wouldn't say, ‘Gee, what’s my ideology? Is that a problem?’”
In 1971, Lewontin resigned membership from the National Academy of Sciences because of its willingness to furnish classified reports for the Department of Defense. (The Vietnam War was still raging at the time.) “That’s a huge step to take. It’s practically like declining a Nobel Prize,” Rose says.
Joseph Graves, a professor of biological sciences at North Carolina Agricultural and Technical State University, says that the resignation is one of the deeds for which he most respects Lewontin. Combating the misuse of science, for racism or other purposes, has substantial consequences, he says: “There are real costs to standing up and fighting back. You really have to be willing to accept the animosity and the lack of professional opportunities that result from taking a stand on a matter of principle.”
Rose worries that taking such controversial stands may be more difficult for scientists today than it was in Lewontin’s time. Many scientists, particularly those early in their careers, work on short-term contracts and don’t have the security of tenure. “The Academy has not become a place for easy critical thinking at the moment, especially if you’re a young scientist trying to make your career,” Rose says.
But because he was so open about his politics, says Graves, Lewontin was not only a uniquely political scientist but also a uniquely honest one. “The simple fact of the matter is that political positions have always been part of science,” Graves says. “People who say they aren’t are just lying.”