why do we still believe in race?

cheltenham festival of science, 6 june 2003

Why do we still believe in race? There are two common answers, depending on side of the fence you stand on the meaning of race. Those who believe the race is a real biological entity argue that we still believe in it - well, because it's a real biological entity. For such so-called race realists, race describes the way the world is organised. Those who view race, not as a biological entity but as a social construction, argue that race is a figment of racist imaginations. Science, they claim, has disproved the reality of race, and only prejudice gives it validity.

I want to suggest that both arguments are wrong. First, the question of whether race is a biological reality or a social construction is not one that science can answer. Science can provide us with data about differences between human populations, but how we interpret that data - and whether we believe that the data points to the reality or otherwise of race - is beyond the domain of science. Second, underlying the idea of race today is not so much a belief in the inequality of human groups as a vaguer sense of the importance of human differences. And this sense of the importance of human differences, as opposed to human commonalities, is something common to both sides of the race debate. What maintains a belief in race today, I want to argue, is not a residual attachment to ideas of racial science, but the contemporary desire to celebrate difference - together with the belief that we should look to science (rather than to, say, politics) for answers to questions of who we are.

Ironically, the more we find out about human biology, the more uncertain scientists appear to be about the meaning of race. The Human Genome Project was supposed to settle the question of race once and for all, by allowing us to compare the genomes from individuals belonging to different 'races'. But when scientists did just that, they came up with very different answers about the biological meaning of race. According to Craig Venter who led the private sector assault on the human genome, 'The Human Genome Project shows there is no such thing as race'. Venter's company Celera used DNA from three females and two males who identified themselves as Hispanic, Asian, Caucasian or African American. 'In the five genomes, there is no way to tell one ethnicity from another', Venter told a press conference in the White House.

Not all scientists agreed. In a major paper in the journal Genome Biology, the geneticist Neil Risch and his colleagues dissented from the party line, arguing that 'from a scientific perspective', racial categories have 'great validity'. 'A decade or more of population genetics research', they insisted, 'have documented biological differences between the races.'

Why such confusion about the meaning of race? Why can't geneticists agree among themselves whether the Genome Project shows racial differences to be a biological reality or a social myth? Science provides us with objective data about human differences. The genetics of population differences is a biological reality, not a social construction. But the interpretation of such differences is deeply shaped by social and political trends. Another way of putting this is that science can neither confirm nor disconfirm race as a biological reality, because race is a not scientific category.

To see this more clearly, I want to look at both the traditional liberal arguments against the idea of race as a biological category and the arguments of those who insist that racial differences are rooted in scientific evidence. Both sets of arguments, I want to suggest, are found wanting - because the debate about race cannot be settled as a scientific issue.

Is race a social construction?

The scientific consensus today is that race is meaningless as a biological category. Three main arguments are used to justify this belief. First, that more than 90% of human genetic variation exists within populations; less than five per cent distinguish what are commonly called 'races'. Second, that all human populations merge into each, ensuring that there are no sharp distinctions between human groups. And third, that Homo sapiens is too young a species for racial differentiation to have deep evolutionary roots. Let us look at these arguments in turn.


'Ninety per cent of variation exists within populations'

Imagine that some nuclear nightmare wiped out the entire human race apart from one small population - say, the Masai tribe in East Africa. Virtually all the genetic variation that exists in the world today would still be present in that one small group. That's a dramatic way of expressing the results of a landmark analysis conducted by the geneticist Richard Lewontin in 1972. From a study of variation in human blood types, Lewontin showed that virtually all of the difference - 85 per cent - occurred between individuals within single populations. A further 7 per cent differentiated populations within a race. Only 8 per cent of total variation distinguished the major races. Lewontin's paper caused a sensation, and remains to this day one of the most frequently cited academic papers. In a stroke, Lewontin seemed to have demolished any scientific rational for the idea of race.

The results from a recent study by Noah Rosenberg and his colleagues published in Science are even more striking. They show that differences among individuals account for a staggering 93-95 percent of all genetic variation. About 2 per cent is taken up by differences between populations within a race. And race accounts for just 3-5 per cent of all human difference. The Rosenberg study is the largest of its kind and these figures are now widely accepted as the most accurate.

All this seems to back up the argument very strongly that race has no biological meaning. We know, however, that tiny genetic differences can have huge physical or behavioural impacts. From a genetic point of view poodles and greyhounds are almost identical, as are dachsunds and St Bernards. Humans and chimpanzees share 99.4 per cent of functional genes, but we're different species. Tiny genetic differences, in other words, can lead to major phenotypical changes. The fact that race accounts for only 4 per cent of genetic variation among humans does not necessarily mean that race has no biological validity.


'There are no sharp distinctions between populations'

The people of China look very different from those of Kenya. But there is no point between Nairobi and Beijing at which the race to which Kenyans belong ends and those to which Chinese belong begins. Every population shades imperceptibly into another. Since there are no clearcut divisions between populations, many geneticists suggest, so race cannot exist in any meaningful sense.

Even race realists acknowledge the difficulty of defining races. 'The precise number and grouping of races will always be somewhat arbitrary', Jon Entine writes. Dividing humans into races 'is akin to wrestling an octopus into a shoe box: no matter how hard you fight with it, you still have something dangling out somewhere. Modern typologists cannot even agree whether it is more meaningful to lump races into large fuzzy groups or split them into smaller units of dozens or even hundreds of populations.'

When even a strong proponent of the race concept admits that it is next to impossible to divide humans into a clean set of races, perhaps it is time to give up on the idea. The fuzziness of boundaries between races, however, does not necessarily mean that races don't exist. Many real categories have fuzzy boundaries. Among non-human animals, for instance, subspecies are often separated by a continuous gradation rather than by a sharp boundary.

Recent genetic studies suggest that it is indeed possible to divide up humanity into a number of major groups which closely correlate with classical concepts of race. Consider, for instance, the study by Noah Rosenberg and his colleagues that I mentioned earlier and which showed that the difference between races accounts for as little as about 4 per cent of total human variation. The same study also showed that despite the fact that most variation occurs among individuals, it is nevertheless possible - in fact quite easy - to distinguish genetically between races.

The scientists studied 377 microsatellite sequences from 1056 individuals from 52 populations worldwide. They fed the data to a computer programme called structure which takes any set of data and attempts to find a rational way of dividing it into as many groups as it is asked to. The number of groups into which the data set is broken down is denoted by the letter K.

In this study, structure was asked to divide up the populations of the world (represented by the 52 DNA samples) into two, three, four and five groups according to how similar or dissimilar were their DNA sequences. When the scientists set asked the programme to divide the population of the world into two groups, one group comprised of Africa, Europe and western Asia and the second group of eastern Asia, Australia and the Americas. When K=3, the group consisting of populations from Eastern Asia and the Americas remained unchanged. But the populations of sub-Saharan Africa were separated from those of Europe and Western Asia. In other words, the three groups were the populations of sub-Saharan Africa, those of Europe and Western Asia, and those of Eastern Asia, Australia and the Americas. When asked to create four groups, structure created a new group by separating the populations of eastern Asia and the Americas. And when asked to break the data into five groups, structure kept all the other groups as they were but separated off the populations of Austral ia from the rest of Asia.

There are two things remarkable about these findings. First, the computer programme divides the population of the world according to the continent on which they live, and as we move from K=2 to K=5 the boundaries of the continents become ever more distinct. Second, when the world's populations are divided into five groups, those five groups correlate closely with what we call 'races': Africans, Caucasians, Orientals, Australasians and Native Americans. And all this from DNA sequences in which only 4 per cent of total human variation is apportioned out among the races. Rosenberg's study seems to suggest that, however small the differences between races, they are nevertheless sufficient to pick them out.


'Homo sapiens is too young species for race to have any meaning'

As a species, Homo sapiens emerged from the East African savannah some 150,000 years ago. The first bands of modern humans did not leave their African home until around 60,000 years ago. Any differences between races, therefore, must be at most 60,000 years old. For many, there simply has not been sufficient time for deep divisions to develop between races. As the late Stephen Jay Gould put it, 'Homo sapiens is a young species, its division into races even more recent. This historical context has not supplied enough time for the evolution of substantial differences... Human equality is a contingent fact of history.'

We know, however, of many mutations that have spread rapidly in a short space of time. The gene for lactose tolerance, for example, which allows human adults to digest milk became dominant in those communities that started practicing agriculture around 10,000 years ago. Today, lactose tolerance is widespread among people who come from areas that have a long history of agriculture - including Europe, the Middle East and South Asia - or who rely extensively on milk in the diets, such as the Fulani in West Africa. But people from other areas - such as East Asia - remain lactose intolerant, and find it difficult to digest milk.

Similarly, genes that confer protection against malaria are also thought to spread through particular populations - that is, those populations under threat from malaria - in the space of a few thousand years. The quickness with which such mutations can spread, and allow one population to be distinguished from another, have led some race realists to query the received wisdom that Homo sapiens is too young a species for races to have properly developed.

In any case, genetic differences between races are unlikely to be the product solely, or even primarily, of natural selection. They are rather likely to be the consequence of two other evolutionary forces, whose impact is less time-limited - genetic drift and the founder effect.

Genetic drift refers to the random changes to gene frequencies that can occur over time, especially in a small population. The most extreme case of genetic drift is called the 'founder effect'. Suppose a small number of people leave their community to form a new one. The people who make up the new community are unlikely to have exactly the same genetic profile as the original population. The smaller the new community, the more likely it will have a distinct genetic profile.

All the people in the world today are descended from small bands of Africans - perhaps no more than a few hundred in each band - who moved out of that continent some 60,000 years ago. Each group would have had a genetic profile slightly different from that of the African population whence they originated. Some genes would have been more common, others less common than in the mother population. Along the way, as they journeyed out of Africa, these small bands of original explorers would have picked up new genetic mutations. And thanks to genetic drift, the genetic profiles of the new and the old populations would have continued to move apart.

The combination of genetic drift and the founder effect, race realists argue, together with genetic mutations that these early migrants would have picked up on their journeys, would be sufficient to explain major differences between the races. Humans may be a young species, they say, but that does not deny the biological reality of race.


Is race a biological reality?

So, does science really tell us that race is a biological fact? Despite what I've just argued, it does not. For while science does not absolutely close the door on the idea of race, it certainly does not open it either.

The debate about race is not a debate about whether differences exist between human populations. Jon Entine, a staunch defender of the idea of race, defines race as 'human biodiversity'. That's meaningless. No one, on either side of the debate, would deny that there are a myriad of differences between different human populations. The real debate about race is not whether there are any differences between populations, but about the significance of such differences.

The fact that a BMW is a different colour from a Boeing 747 is of little significance to most people. The fact that one has an internal combustion engine and the other a jet engine is of immense significance if you want to travel from London to New York. But if you are a Yanomami Indian living in the Amazon forest, even this difference may not be of that great a significance, since it's unlikely that you will be able - or need - to use either form of transport.

If we want to understand the significance of any set of differences, in other words, we have to ask ourselves two questions: Significant for what? And in what context? One of the problems of the contemporary debate about race is that these two questions get too rarely asked.

In the nineteenth century races were seen as fixed groups, almost akin to distinct species, each with special behavioural and physical characteristics that distinguished one from the other. The races could be ranked on an evolutionary hierarchy, with whites at the top and Negroids at the bottom.

Today, with a few exceptions, race realists reject the idea that there are essential differences between human populations, or that differences signify inferiority or superiority. But that's made race a very flaky concept. No one knows quite how to define it. The problem for race realists today is the very opposite of that for nineteenth century racial scientists. Racial scientists 'knew' the significance of race but could find no way of truly defining differences. Today, as the study by Rosenberg and his colleagues clearly reveals, we can define differences between Continental populations. But the significance of such differences no longer seems clear.

To understand this better, I want to look at one area in which the biological concept of race does seem relevant - medicine. We know that many diseases are colour-coded. In Britain there is particular concern about diabetes among Asian men. In America, African-Americans suffer disproportionately from hypertension. Tay-Sachs disease is found particularly among Jews.

Many doctors and geneticists have suggested that medicine shows up the reality of race. As a doctor, Sally Satel, put it in a widely-reported essay in the New York Times,

In practicing medicine, I am not colorblind. I always take note of my patient's race. So do many of my colleagues. We do it because certain diseases and treatment responses cluster by ethnicity... When it comes to practicing medicine, stereotyping often works.

At the Washington drug clinic where she works, Satel prescribes different amounts of Prozac to black and white patients because African Americans seem to metabolise antidepressants more slowly than Caucasians.

Yet, though different populations exhibit distinct risk profiles for diseases and disorders, we should be wary before suggesting that this establishes the reality of race. Sally Satel tells us that 40 per cent of African Americans metabolise anti-depressants more slowly than do Caucasians. That means that the majority of black Americans respond in the same manner as do Caucasians. There might be medical advantages in treating blacks and whites differently with respect to anti-depressant uptake, in other words, but such differential treatment tells us nothing about racial differences except in a most superficial sense.

The real medical advantage would come from being able to genotype each individual, and hence be able to create a risk profile for each one. Such a project is currently unfeasible for both practical and financial reasons. Therefore doctors often resort to using surrogate indicators of an individual's risk profile - such as race. Knowing the continent from which an individual's ancestors originally came can provide clues as to what genes that individual might be carrying. It's what Sally Satel calls a 'poor man's clue'.

But a poor man's clue in medicine is often a very poor clue to race. We all know, for instance, that sickle cell anaemia is a black disease. Except that it isn't. In the USA, the presence of the sickle cell trait can help distinguish between those with, and without, African ancestry. But not in South Africa. In South Africa, neither blacks nor whites are likely to possess the trait. That's because sickle cell is not a black disease, but a disease of populations originating in areas with high incidence of malaria. Some of these populations are black, some are not. The sickle cell gene is found in equatorial Africa; in parts of southern Europe; in southern Turkey, parts of the Middle East; and in much of central India. Four distinct types of sickle cell genes have been discovered, relating to different populations.

So, given the diversity of populations suffering from the sickle cell trait, why do we think of sickle cell anaemia as a black disease? Because most people know that African Americas suffer disproportionately from the trait. And, given popular ideas about race, most people automatically assume that what applies to black Americans also applies to all blacks. It is the social construction, not the biological reality, of race that turns sickle cell into a black disease.

There's a similar picture with diabetes. In the USA, Hispanics are nearly twice as likely to have diabetes than whites. Hispanic, however, is not a biological category. The Hispanic population is made up three Continental groups - Caucasian, African and Native American. It has become a population group only because of the peculiarities of immigration into the USA.

If we break down the Hispanic population into its three main sub groups by country of origin - Mexicans, Puerto Ricans and Cubans - we see that the incidence of diabetes is much lower in Cuban Americans than in the other two groups. Some have suggested that this is because Cuban Americans have a much lower African and Native American ancestry than do Mexicans or Puerto Ricans - and that both Africans and Native Americans have greater predisposition to diabetes. But if we look at the genetic origins of the three main Hispanic groups we find that Cuban Americans have a percentage of Native American genes no different to Puerto Ricans, while when it comes to their African heritage they stand in between Mexicans and Puerto Ricans:

Genetic origins of the Hispanic subgroups in the USA

(in per centage terms)

  Caucasian African Native American



It is difficult, in other words, to explain the lower incidence of diabetes among Cuban Americans in terms of their distinct racial ancestry. The biology of race, can tell us little about the differences between the incidence of diabetes either within the Hispanic community, or between Hispanics and whites.

Population differences are clearly important in medicine. But we should not confuse these with racial differences. The boundaries of a population, and the differences that matter, vary depending on the question we are asking. Do we want to know about sickle-cell anaemia, diabetes or Tay-Sachs disease? Are we concerned with population differences in Britain or the USA? And so on.

Sally Satel called race a 'Poor man's clue' in medicine. It's a telling phrase. Race provides a clue because there are clearly genetic and social differences between population groups that have medical consequences. But it's a poor clue because the way we divide up society into different groups is not necessarily the most useful way to understand a disease or disorder.

So, we return to the question: is race a biological category? What the 4 per cent of variation that marks the difference between races tells us is the continent whence your ancestors originated. The 4 per cent comprises largely of genes responsible for relatively superficial features, such as skin colour, bodyform or certain physiological functions like drug uptake. It has been estimated, for instance, that skin colour, accounts for more than half the measured genetic difference between Continental groups. Virtually no expressed genes have been identified that are shared by all members of one race and are not also present at substantial levels in other races. There is no evidence that races exist in the old-fashioned sense of clearly delineated groups of people each with a special, essential quality. Not even race realists believe that these days. Which makes it hard to know what they do believe.

What race expresses today is a much vaguer belief about the importance of human differences, a sense that what matters are our particular identities, that these are in some sense fixed and inviolable, and that preserving and celebrating such differences and identities is essential to the healthy functioning of human societies.

Looked at in this fashion, the division between the two sides in the race debate is actually far less than might otherwise appear. For the celebration of difference has become the hallmark, not of racists, but of modern, liberal democracies. 'It's good to be different' might well be the motto of our times. The celebration of difference, the promotion of a pluralist society, tolerance for a variety of cultural identities - these are seen as the hallmarks of a decent, liberal, democratic, non-racist society.

From this perspective, modern race realism is not a throwback to nineteenth century racism, but an expression of the contemporary embrace of pluralism. To be sure race realists stress the importance of biological diversity, anti-racists of cultural diversity. But the real division, I want to argue, is no longer between those who see the world through racialeyes and those who see see it through cultural eyes. It is rather between what the anthropologist Leonard Lieberman has called 'lumpers' and 'splitters' - between those who stress the importance of human commonalities and those who stress the importance of human differences.

The political debate about race has always involved two distinct arguments: one about equality, the other about universality. The first is an argument about whether human beings possess a fundamental sameness by virtue of being human. The second is an argument about whether or not what humans have in common is more important than our differences. The relationship between these two arguments has changed over time.

In the nineteenth century, most people accepted that different races were real entities and that different races were unequal. The main debate was about whether or not they were different species - in other words, were non-whites human? By the beginning of the twentieth century, the main debate revolved around whether races were unequal or just different. In the postwar world, most (though not all) anthropologists came to accept that humanity had a common origin and that races did not express unequal endowment. The debate now was whether the concept of race had any validity at all.

In this process, the relationship both between lumpers and splitters, and between the debate about equality and that about universality, also changed. In the nineteenth century splitters believed in the inequality of races and often claimed, too, that different races had distinct evolutionary origins; lumpers, on the other hand, believed not just in a common origin for humanity, but denied that different groups could be ranked on a scale of intelligence and civilisation. Lumpers, in other words, believed in both universality and equality. Splitters were hostile to both. Today, however, this clean distinction between lumpers and splitters is no longer easy to make - because, by and large, both lumpers and splitters now profess a belief in the equality of human groups. Nor is there any longer a straightforward association between equality and universaility. Many of those who today subscribe to the idea of human equality also deny the idea of human universals. Indeed, 'anti-racism' has today come to mean hostility to the idea of universality and the advocacy of cultural, and sometimes moral, relativism.

All of which brings us to another transformation in the postwar understanding of human differences. Increasingly, people have come to view differences not so much a function of biology as of culture. The denial of the importance of racial divisions has gone hand in hand with the acceptance of the idea that cultural divisions are deep, ingrained and necessary. By the beginning of the twenty-first century, we have come to view cultural differences in much the same way as people had viewed racial differences at the end of the nineteenth.

To understand all this better, I want to take a historical detour, to look at how the idea of race developed over the past three centuries, and at the relationship between ideas of racial and cultural differences.


A brief history of race

People have always recognised differences between populations. But they have not always viewed those differences as racial. The modern idea of race is relatively recent - no more than three centuries old. Before the modern concept of race could develop, the modern concepts of equality and humanity had to develop too. Racial difference and inequality can only have meaning in a world which has accepted the possibility of social equality and a common humanity.

It was through the Enlightenment, the intellectual transformation of Europe in the eighteenth century, that such ideas became firmly established in the modern imagination. Whatever their other differences most Enlightenment thinkers held that humans were by nature rational and sociable, and that there existed a common human nature. Implicit in these beliefs was the idea that all humans were potentially equal. Through Enlightenment philosophy humanity had for the first time a concept of universality that could transcend perceived differences.

What is striking about Enlightenment discourse is the lack of any discussion of race. Compared to writings both before and after, eighteenth century writings show a remarkable disdain for racial arguments. When in 1800, the French anthropologist Joseph-Marie Degerando wrote a methodological text for the Société des Observateurs de l'Homme, the principal anthropological society of its time, he did not think it necessary to deal with the question of race. Of course Enlightenment thinkers clearly held racist views, some very openly and overtly. It would have been astonishing if it had been otherwise. But what was absent at this time was any sustained discourse of race.

Enlightenment thinkers believed that all humans were potentially equal, and that social progress would overcome divisions. But by the early decades of the nineteenth century such optimism seemed misplaced. Far from healing social divisions, industrialisation and progress appeared to exacerbate them. Within European nations, there developed a yawning gulf between the advancing middle classes and the working class and rural poor, who, to middle class eyes at least, seemed shackled to ignorance and poverty. An equally deep chasm had opened up between European nations and those of Africa or Asia, which Europeans increasingly thought of as incapable of civilisation.

Many prominent thinkers became convinced that certain types people were by nature incapable of progressing beyond barbarism. They were naturally inferior. The idea of race developed as a way of explaining the persistence of social divisions in a society that had proclaimed a belief in equality. From the racial viewpoint, inequality persisted because society was by nature unequal. The destiny of different social groups was shaped by their intrinsic properties.

Racial thinkers divided humanity into discrete groups, each with particular properties, and the divisions between which seemingly being immutable and unchanging. Racial ideology was the inevitable product of the persistence of differences of rank, class and peoples in a society that had accepted the concept of equality. People came to understand the world in racial terms because there seemed to be no other way through which to make sense of the world around them.

Key to this process was the emergence of the Romantic movement. The Romantics rejected what they saw as the abstract nature of Enlightenment universalism, and championed instead particularist accounts of human difference. They considered every people to be unique, and that such uniqueness was expressed through its volksgeist, the unchanging spirit of a people refined through history. The idea of volksgeist became transformed into the concept of racial make-up, an unchanging substance, the foundation of all physical appearance and mental potential and the basis for division and difference within humankind. At the roots of modern racism, therefore, lie Romantic visions of human differences.

Ironically, though, Romantic notions of human differences also lie at the heart of contemporary visions of cultural pluralism. Following the experience of Nazism, the Holocaust and the Final Solution, biological theories of human differences became discredited. But while the biological arguments for racial superiority were thrown into disrepute many of the assumptions of racial thinking were maintained intact - in particular the belief that humanity can be divided into discrete groups, that each groups should be considered in its own terms, and that differences, not commonalities, shaped human interaction. These assumption, however, were cast not in biological terms but in the language of cultural pluralism.

Pluralism took the Romantic idea of human differences and refashioned in a non-racist way. It effectively turned on its side the evolutionary ladder of Victorian racial theory, conceiving of humanity as horizontally, rather than vertically, segmented. Humanity was not arranged at different points along an ever-rising vertical axis, as the racial scientists had believed, but at different points along a stationary horizontal axis. Humanity was composed of a multitude of peoples each inhabiting their own symbolic and cultural worlds. Pluralism provided a vocabulary with which to articulate particularist identities without having to refer to the discredited discourse of race. And in the 60 years since the Second World War, it has become a key way of thinking about human societies - especially for anti-racists.

What pluralism does is to disconnect the relationship between universalism and equality. All people are equal - but only because every group is different. As the sociologist and feminist Sonia Kruks put it in a recent book:

The demand is not for inclusion within the fold of 'universal humankind' on the basis of shared human attributes; nor is it for respect 'in spite of one's differences'. Rather, it what is demanded is respect for oneself as different.

Such 'identity politics' is clearly rooted in Romantic views of human difference. And through such identity politics, the celebration of difference, which once was at the heart of racial science, has become a key plank of the anti-racist outlook. The result has been an increasing convergence in recent years between anti-racist and race realist views.

On the one hand, race realists now portray themselves as pluralists. Charles Murray and Richard Herrnstein, for instance, authors of the notorious The Bell Curve, claim that they are simply making a case for 'conservative multiculturalism':

It is possible to look ahead to a world in which the glorious hodgepodge of inequalities of ethnic groups - genetic and environmental, permanent and temporary - can be not only accepted but celebrated...
Each clan will add up its accomplishments using its own weighting system will encounter the world with confidence in its own worth and, most importantly, will be unconcerned about comparing its accomplishments, line by line with those of any other clan. This is wise ethnocentrism.

Or, as Sonia Kruks would put it, 'What is demanded is respect for oneself as different.'

And on the other hand, anti-racists have increasingly begun to view cultural identity in natural terms. You might have seen Motherland, the BBC documentary last year in which three black Britons traced their genetic ancestry. Bristol youth worker Beula McCalla was told that was told that her gentic lineage traced back to the tiny island of Bioko, off the coast of Cameroon. The next thing, she was off on a plane to be reunited with her long-lost relatives, the Bubis. 'I've found who I am', she sobbed. 'I've found my home.'

Ten years ago, black identity might have been seen as cultural or political expression. Now it's increasingly seen as genetic heritage, inextricably linking race, culture and identity. According to Joseph Harker, former editor of the Voice, Britain's leading black newspaper, genetics provides black people with 'a route to a new identity', a reconnection with 'their own brothers sisters and cousins' and the possibility of 'a whole new history and culture'.

Genetics cannot, of course, do any such thing. But it's not just black Britons who nowseek their history and culture in their biological past. Jews, Icelanders, Macedonians - everyone, it seems, is looking to genetics as the soil in which to root their culture and sustain their identity.

Superficially, all this might seem like a throwback to nineteenth century racial science. But it is very much a 21st century phenomenon. As societies become more fragmented, as social bonds seem ever more fragile, and as social emancipation more and more seems a mirage, so there is a desperate search for meaning in ever-narrower and seemingly more foxed identities. And as the sphere of politics visibly shrinks by the day, so people increasingly look to science to answer the kinds of questions that science simply cannot answer. And that is why I think we still continue to believe in race. It's an attempt to find in the past and in science the certainties we can no longer find in the present and in society.