Society · By Amaya Kavya · 2026-07-14 · 12 MIN

Us and Them: Why Humans Invented Race

Every people on earth has, at some point, looked at itself and decided it was the standard by which everyone else falls short. That instinct is ancient and universal. But the idea of a few ranked biological races is neither. It is recent, it was built on purpose, and the science does not support it. This is where discrimination by race actually comes from, and why understanding it is the thing that undoes it.

Split a room of strangers into two teams by the flip of a coin, tell them nothing else about each other, and within minutes they will start to favour their own side. This is not a guess. In a famous set of experiments in the 1970s, the psychologist Henri Tajfel sorted people into groups on the flimsiest possible basis, once by asking which of two abstract painters they preferred. The people never met, never spoke, had nothing to gain personally. And still, when asked to hand out small rewards, they gave more to their own group and less to the others, sometimes even choosing a worse deal for their own side just to keep the gap between the two. All it took to switch on the bias was a label.

That experiment holds the first half of the answer to a hard question: why did human beings ever start dividing themselves up and deciding their own kind was better. The instinct to split the world into "us" and "them" turns out to be built in, cheap to trigger, and found everywhere. But it also holds a trap, because it makes racism feel natural and permanent, like weather. It is not. The instinct is old and universal. The thing we call race is young, and it was made. Telling those two apart is the whole point.

The old part: us and them

Start with the bit that really is ancient. For almost all of the human story, people lived in small groups where survival depended on trusting the people around you and being wary of the ones you did not know. A band that cooperated tightly on the inside and kept its guard up against outsiders tended to last. So we are the descendants of world-champion group-formers, wired to read who is in and who is out, and to feel warmer towards our own.

You can see the result in the fact that so many peoples, all over the world and with no contact between them, gave themselves names that simply translate as "the people" or "the human beings", quietly implying that everyone else is something a bit less. This habit of treating your own group as the measure of normal, and everyone else as a deviation from it, has a name: ethnocentrism. Anthropologists find it almost everywhere they look. It is not a white thing or an Asian thing or an African thing. It is a human thing. Every group that has ever felt superior on its own ground was running the same ordinary software.

Here is the part that matters, though. That instinct does not care about race. It will happily attach itself to anything: your village against the next one, your religion against theirs, your football club, your school, two painters you were asked to choose between. The machinery is general. It just needs a line to defend. Race is one line it can grab, but for most of history it was not even the obvious one.

Race was not the original dividing line

We tend to assume people have always sorted each other by skin colour into a handful of big races. They have not. For most of recorded history the lines that mattered were religion, language, tribe, city and class. The ancient Greeks split the world into Greeks and "barbarians", but a barbarian was anyone who did not speak Greek, whatever they looked like. The Romans enslaved people from every corner of their empire, pale and dark alike, and an enslaved person who was freed could become a citizen. Slavery was ancient and brutal, but it was not yet organised around the idea that humanity comes in a few colour-coded kinds, some born to rule and others born to serve.

That idea, the one we now mean by race, is only a few centuries old. And once you see when and why it appeared, the whole thing starts to make a grim kind of sense.

Where the idea of race was built

From the 1500s onwards, European powers spread across the Americas, Africa and Asia, and built an economy on an enormous scale of forced labour, above all the transatlantic slave trade that shipped around twelve million Africans across the ocean in chains. This created a problem that was not military or practical but moral. The very same centuries produced the Enlightenment, with its ringing talk of liberty, natural rights and the equality of all men. It is hard to declare that all men are created equal in the morning and run a slave plantation in the afternoon. Something had to give.

What gave was the definition of "all men". If the people being enslaved and dispossessed could be defined as a different, lesser sort of human, then the contradiction dissolved. You were not denying liberty to your equals. You were dealing with a lower order of being. The hierarchy did not come from careful study of human beings. It was worked backwards from what powerful people were already doing and wanted to keep doing.

Then came the scientists to make it look respectable. In 1735 the great classifier Carl Linnaeus, the man who organised all of life into neat categories, split humans into four types by continent and colour, and could not resist tacking a personality onto each, calling Europeans inventive and Africans lazy, with no evidence beyond his own prejudice. In 1795 Johann Blumenbach went further, naming five races, inventing the word "Caucasian" for Europeans, and arranging the five with Caucasian as the original and most beautiful and the others as degraded departures from it. He added skull measurements and Latin names, and suddenly a ranking that was really about power looked like biology. In the next century Arthur de Gobineau spun it into a full myth of a master "Aryan" race, an idea that would eventually help carry Europe into the gas chambers.

None of this was neutral discovery. It was a story written to justify a system, and it is worth being honest that Europeans do not hold a monopoly on the underlying impulse. Plenty of societies have ranked people by descent and shade, from caste systems to the idea that one's own civilisation sits at the centre of the world. The instinct to build a pecking order and call it natural is widespread. But the specific machinery of modern race, the small set of colour-coded biological ranks, was assembled and exported during the age of European empire, because that is who was doing the conquering and needed the excuse.

What the science actually found

Here is where the story turns, because the biology those men reached for to prop up the ranking eventually knocked the whole thing down.

In 1972 the geneticist Richard Lewontin measured how human genetic variation is actually distributed. If races were real biological divisions, most of our genetic differences should sit between them. He found the opposite. More than 85 percent of all human genetic variation is found within any single population, and less than 15 percent lies between the big groups we call races. In plain terms, two random people from the same so-called race are almost as different from each other, genetically, as two people from opposite sides of the planet. There is more genetic diversity inside Africa alone than in all the rest of the world combined, because that is where our species spent most of its existence before a small group wandered out and populated everywhere else.

Skin colour, the thing the whole hierarchy was hung on, turns out to be one of the thinnest differences of all. It is mostly an adaptation to sunlight. Nearer the equator, darker skin protects the body from strong ultraviolet radiation. Further from it, lighter skin lets the body make enough vitamin D in weaker light. It is sunscreen and vitamin management, it has evolved separately more than once, and it tells you almost nothing about the rest of a person's biology. Judging human worth by it is like sorting books by the colour of their covers.

This is now the settled view of the people who study it. A survey in 2017 of more than three thousand anthropologists found near-total agreement that biological races do not exist in the human species. Any two human beings, whatever they look like, share about 99.9 percent of their DNA. Race is real in the way that borders are real, as a powerful social fact with enormous consequences for people's lives. It is not real in the way gravity is real. It was drawn, not found.

Why it holds on, and how it loosens

If race is invented and the science is this clear, why does it grip so hard. The answer goes back to the beginning. The ancient us-and-them machinery is still humming away inside us, and race gives it an unusually sticky handle to grab: it looks visible, it looks inherited, and children are taught the categories young, before they can question them. A made-up line, drawn often enough and enforced long enough, starts to feel like part of the landscape.

But the same research that shows how easily we form groups also shows how easily the lines can be redrawn. Give two hostile groups a shared problem that neither can solve alone, and the hostility drains away as a bigger "us" forms over the top of the old split. The circle of who counts as our people is not fixed. It has widened many times in history, from the family to the tribe to the nation, and there is nothing in our wiring that stops it widening again. The instinct is permanent. Its target is a choice.

That is the part worth holding on to. The reflex to favour your own is the single most universal thing about human beings, which means it is, absurdly, one of the few things that every race truly has in common. The pecking order laid over the top of it was invented a few centuries ago by people who needed an excuse, and dressed in a lab coat by people who mistook their prejudice for measurement. Seeing that clearly does not switch the old instinct off. But it does something quieter and more useful. It shows you the line for what it is, a thing somebody drew, on a single species, on a small blue planet, that from far enough away has no lines on it at all.

Sources

Delvewire