Race: Classification and Biological Significance in Human Populations

Say the word “race” and most people picture skin colour, hair texture, or facial features. Anthropologists have spent nearly a century trying to pin this idea down scientifically, and the story of that effort tells you more about how science works than it does about human bodies. From Earnest Hooton’s tidy 1920s definition to Ashley Montagu’s outright rejection of the term, the concept of race has been debated, redefined, and largely dismantled within biological anthropology itself. Here’s how that debate unfolded, and why it still matters for how we think about human diversity today.

How early anthropologists defined race 🔗

In the early twentieth century, physical anthropologists tried to classify humans the way naturalists classified other species: by grouping people according to shared physical traits passed down through generations. American anthropologist E.A. Hooton offered one of the most cited definitions in 1926, describing race as a major division of humankind whose members, while varying individually, share a combination of physical and measurable features that are largely non-adaptive and inherited from common ancestors, as outlined in anthropology teaching material from IGNOU.

Two details in this definition mattered a great deal to Hooton and his contemporaries. First, the traits used to define a race had to be non-adaptive, meaning features like head shape or nose form rather than traits shaped directly by climate or diet. Second, these traits had to be traceable to a shared line of descent. Building on this framework, Hooton went on to classify humanity into broad categories such as Caucasoid, Mongoloid, and Negroid, a scheme that built on earlier typologies from scholars like Johann Blumenbach, who had proposed similar racial categories more than a century earlier.

Why this approach ran into trouble 🔗

The typological method assumed that humanity could be neatly sorted into a handful of discrete boxes. In practice, physical traits like skin tone, hair form, and head shape vary gradually across geography rather than breaking into clear boundaries. Populations living between two “typical” racial zones often show a blend of features, not a clean split. This gradual, overlapping pattern of variation is what anthropologists call clinal variation, and it made the older typological system increasingly difficult to defend on its own terms.

The subspecies argument in biology 🔗

A more recent attempt to rescue the race concept borrows from population genetics. In this view, races are treated as biological subspecies: groups within a species whose members share closer ancestry with each other than with populations classified into other groups. This framing shifts the basis of race from visible anatomy to shared gene pools shaped by geographic isolation.

The trouble is that human populations rarely meet the criteria biologists use to define subspecies in other animals. A genuine subspecies usually shows a long period of geographic isolation, limited gene flow with neighbouring groups, and a consistent, diagnosable set of genetic markers unique to that population. Human groups, by contrast, have a long history of migration, contact, and interbreeding, which keeps gene flow between populations relatively high and blurs any sharp genetic boundary.

What the genetic data actually shows 🔗

The clearest evidence against treating races as biological subspecies came from population geneticist Richard Lewontin’s landmark 1972 study. Analysing genetic variation across populations that had historically been grouped into races, Lewontin found that roughly 85 percent of human genetic variation exists within so-called racial groups, while less than 15 percent accounts for differences between them. In other words, two people from the same “race” can be as genetically different from each other as either one is from someone in a different racial category.

This finding has been revisited and largely confirmed by later researchers using modern DNA sequencing, as detailed in a retrospective marking fifty years since the original study was published. The pattern makes sense once you consider human evolutionary history: our species is comparatively young, has never been split into long-isolated breeding populations, and has always exchanged genes across neighbouring groups through migration and intermarriage.

Ashley Montagu’s alternative: ethnic group 🔗

Not every anthropologist accepted the race concept even in its more cautious, genetic form. British-American anthropologist Ashley Montagu (1905-1999) became one of the most vocal critics of racial classification from the 1940s onward. Montagu argued that the term “race” carried so much social and political baggage, and rested on such shaky biological ground, that it should be dropped from scientific use altogether.

In its place, Montagu proposed the term ethnic group, a label he felt better captured the reality of human variation: populations that differ somewhat in gene frequencies and physical traits due to geography and history, without implying the fixed, hierarchical divisions that “race” had come to suggest. Montagu didn’t invent the phrase “ethnic group,” but his sustained argument for replacing race with it, developed most fully in his book on the subject, pushed the debate into the mainstream of anthropology. His critique was partly scientific and partly historical, drawing on how the concept of race had been used to justify colonialism, slavery, and discrimination, a connection explored in detail by later historical analyses of his work.

Why the distinction matters 🔗

Montagu’s shift in terminology wasn’t just semantic. Calling human groups “ethnic groups” rather than “races” reframes variation as a matter of shared culture, language, and geographic history rather than fixed, inherited biological categories. This distinction has practical consequences. Medical research, for instance, has increasingly moved away from using broad racial categories as stand-ins for genetic risk, since ancestry-informed and population-specific data tend to be far more accurate predictors of health outcomes than race-based groupings.

Where anthropology stands today 🔗

The consensus among biological anthropologists today reflects Montagu’s scepticism more than Hooton’s typology. The American Association of Biological Anthropologists, the largest professional body in the field, issued a formal statement declaring that race does not provide an accurate representation of human biological variation, adding that humans are not divided into distinct genetic clusters that correspond to continents or popular racial categories. The statement also acknowledges the discipline’s own history of using flawed racial science to support discriminatory ideologies, a history that shaped colonial-era anthropology across the world, including in India.

This doesn’t mean human biological variation isn’t real. Populations do differ in the frequency of certain traits and genes, often shaped by adaptation to local environments, such as skin pigmentation varying with sun exposure or blood-related traits varying with historical exposure to particular diseases. What the evidence rejects is the idea that this variation sorts neatly into a small number of discrete, biologically bounded “races.” India itself is a useful illustration: its population shows enormous physical and genetic diversity across regions and communities, variation that historical racial schemes tried and failed to fit into a handful of fixed types.

A useful distinction for students 🔗

For anyone studying this topic, it helps to separate three things that often get conflated: physical variation (which is real and well documented), race as a rigid biological category (which most contemporary anthropologists reject), and ethnicity or ancestry (which describes shared cultural, linguistic, or geographic history without assuming fixed biological boundaries). Keeping these separate makes it much easier to read both historical anthropological texts and current scientific literature without confusion.

What do you think? 🔗

Given how much genetic variation exists within any single population, does the term “race” still serve any useful purpose in science, or has it outlived its original function? And when you look at India’s own regional and community-level diversity, does thinking in terms of “ethnic groups” rather than “races” change how you’d explain that diversity to someone unfamiliar with it?

References

1. https://egyankosh.ac.in/bitstream/123456789/73689/1/Unit-7.pdf
2. https://egyankosh.ac.in/bitstream/123456789/65800/1/Unit12.pdf
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9014184/
4. https://royalsocietypublishing.org/rstb/article/377/1852/20200405/108841/Celebrating-50-years-since-Lewontin-s
5. https://www.journals.uchicago.edu/doi/10.1086/687748
6. https://bioanth.org/about/aaba-statement-on-race-racism/