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Race? It's a myth, scientists say Biological, genetic research undercuts the idea, experts insist

WASHINGTON -- Thanks to spectacular advances in molecular biology and genetics, most scientists now reject the concept of race as a valid way to divide human beings into separate groups.

Contrary to widespread public opinion, researchers no longer believe that races are distinct biological categories created by differences in the genes that people inherit from their parents. Genes vary, they say, but not in ways that correspond to the popular notion of black, white, yellow, red or brown races.

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"Race has no basic biological reality," said Jonathan Marks, a Yale University biologist. "The human species simply doesn't come packaged that way."

Instead, a majority of biologists and anthropologists, drawing on a growing body of evidence accumulated since the 1970s, have concluded that race is a social, cultural and political concept based largely on superficial appearances.

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"In the social sense, race is a reality; in the scientific sense, it is not," said Michael Omi, a specialist in ethnic studies at the University of California in Berkeley.

Luigi Cavalli-Sforza, an eminent professor of genetics at Stanford University, agreed. "The characteristics that we see with the naked eye that help us to distinguish individuals from different continents are, in reality, skin-deep," he said. "Whenever we look under the veneer, we find that the differences that seem so conspicuous to us are really trivial."

Scientists concede that people do look different, primarily because of the varied environments in which their ancestors lived. And they agree that as a social concept, race matters a great deal. The color of a person's skin, the texture of his hair, or the shape of her eyes can be sources of love, pride and partnership - or fear, hatred and injustice.

Many government policies - such as housing, schools and voting rights - treat "minorities" differently than whites. Resentment over "affirmative action" is a burning political issue in this year's elections. Educators, police and the military routinely ask for racial identification. The Census Bureau officially classifies every American by race, although its categories are widely criticized.

The idea that races are not the product of human genes may seem to contradict common sense.

"The average citizen reacts with frank disbelief when told there is no such thing as race," said C. Loring Brace, an anthropologist at the University of Michigan. "The skeptical layman will shake his head and regard this as further evidence of the innate silliness of those who call themselves intellectuals."

The new understanding of race draws on work in many fields.

"Vast new data in human biology, prehistory and paleontology ... have completely revamped the traditional notions," said Solomon Katz, an anthropologist at the University of Pennsylvania.

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This is a switch from the prevailing scientific dogma of the 19th and much of the 20th century. During that period, most scientists believed that humans could be sorted into a few (usually three, four or five) inherited racial types distinguished primarily by skin color.

Government policies were based on alleged racial inequalities, including U.S. immigration laws designed to screen out "inferior" foreign stocks, bans on interracial marriage and the genocidal horrors of Nazi Germany.

As recently as 1985, anthropologists split 50-50 when one of their number, Leonard Lieberman of Central Michigan University, asked in a survey if they believed in the existence of separate biological races.

A dwindling number of scholars still cling to notions of gene-based racial superiority. In his controversial 1994 book, "The Bell Curve," Charles Murray, a political scientist, asserted that African-Americans inherit lower intelligence than persons of Asian or European descent.

In response to the uproar over "The Bell Curve," the American Anthropological Association adopted a statement declaring that "differentiating species into biologically defined 'races' has proven meaningless and unscientific as a way of explaining variation, whether in intelligence or other traits."

A leading holdout is Philippe Rushton, a Canadian geneticist who continues to claim that crime and violence are biologically determined tendencies.

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"Among humans, three major races of Mongoloids, Caucasoids and Negroids are typically considered," Rushton wrote in the February 1996 Journal of Current Anthropology. "Genetic research has built a strong case for the importance of heritable factors [meaning genes] in personality, psychopathology, violent crime and other social variables."

"Rushton is dead wrong," snapped John Moore, chairman of the anthropology department at the University of Florida, reflecting the majority view.

As a sign of the change, Lieberman said, most anthropology textbooks published in this decade have stopped teaching the concept of biological race.

In part, the new consensus is an effort by scientists to stop the misuse of race to justify the evils of racism.

"Misconceptions about race have led to forms of racism that have caused much social, psychological and physical harm," said Katz. "These misconceptions have their origin in various papers and books that depend heavily on old and outmoded biological concepts of race."

But the revised concept of race also reflects recent scientific work with DNA, the complex molecule that contains the genes in every living cell.

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"We are beginning to get good data at the DNA level," said Kenneth Kidd, a Yale geneticist who studied minute variations in the genes of people from 42 different population groups around the globe. "The DNA data support the concept that you can't draw boundaries around races."

Kidd said there is actually more genetic variation within a single African population - which can be anything from a tribe to a nation - than in all non-African peoples put together.

That is because those Africans who stayed in place gradually accumulated tiny variations in their DNA over thousands of generations. About 100,000 years ago, a few tribes emigrated to Europe, the Middle East and Asia, taking only a small subset of those genes with them. Since the migration, these travelers have not developed as many variations out of their smaller gene pool.

"Genetically, I am more similar to someone from China or the Amazon Basin than two Africans living in same village are to each other," Kidd said. "This substantiates the point that there is no such thing biologically as race."

Researchers say differences in skin color - the most common marker for race - arose from a combination of environmental pressures and random genetic mutations.

Most scientists have come to accept the evolutionary theory, based on DNA evidence, that modern humans (the species homo sapiens) originated in equatorial Africa about 200,000 years ago.

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Our primitive ancestors' genes were programmed to produce dark skin. Their pigment protected them from the tropical sun's ultraviolet rays, which can cause cancer.

The group of Africans who later migrated north into Europe benefited from more sunlight, rather than less, because ultraviolet rays also make vitamin D, preventing rickets and other diseases.

By a flip of the genetic dice, some of the newcomers had a variant gene that gave them slightly lighter skin. These lucky ones tended to get more vitamins, live longer and have more children, who in turn passed the trait on to their descendants.

The trend continued for generation after generation, eventually producing Anglo-Saxons, Swedes and other fair-skinned northern Europeans.

"Skin color genes are turned off and on very quickly in evolution," Moore explained. "People can go from black to white, or white to black, in 10,000 years."

Significantly, populations who live near the equator - in southern India, New Guinea or northern Australia - are just as dark as natives of West Africa, demonstrating that black skin depends more on environment than heredity.

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The farther you go from the equator, north or south, the paler people look. The Bushmen of southern Africa have quite light complexions. Africans from north of the Sahara Desert resemble southern Europeans.

"From one end of this range to the other, there is no hint of a skin-color boundary," said Brace. "The spectrum runs from the lightest in the world at the northern edge to as dark as it is possible for humans to be at the equator."

Meanwhile, controversy continues over the possible link between race and intelligence.

Brace, who is writing a book on the subject, contended that intelligence is the only human trait that does not seem to vary from one population to another. Instead, he said, basic intellectual capacity is distributed equally among all peoples, regardless of their skin color.

"We do get race differences in intelligence tests," Brace conceded, "but that is social, not biological in origin." Environmental and cultural factors - such as poor nutrition, poverty and bad schools - affect IQ scores, but not inherited intellectual capacity, he said.

The clash between laymen's and scientists' concept of race was the subject of a panel discussion sponsored by the American Association for the Advancement of Science last year.

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"The word 'race' has many meanings and many uses, some reputable, some quite disreputable," said John Ladd, a Brown University philosophy professor, who chaired the panel. "We must try to sort out the difference."

Robert S. Boyd wrote this article for Knight-Ridder News Service.

Pub Date: 10/13/96



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