Everyone Is African (20 page)

The westward expansion of European settlement in nineteenth-century North America rapidly accelerated with construction of the US Transcontinental Railroad, accompanied by a major influx of east Asian immigrants to the shores of California to work on the railroad and in mining, agriculture, and other forms of hard labor. Notions of white supremacy were so pervasive at the time that the large number of east Asian immigrants became known as the “yellow menace,” “yellow terror,” and “yellow peril.” National laws in the United States restricting or prohibiting immigration of people with Asian ancestry began with the Page Act of 1875 and continued with the Chinese Exclusion Act of 1882, the Geary Act of 1892, and the “Asiatic Barred Zone” of the Immigration Exclusion Act of 1917.
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By the end of the nineteenth century, the United States had sizable populations of people descended from African and European immigrants as well as
smaller populations descended from east Asian immigrants. By then, Native Americans had been greatly reduced in number, and many were living on reservations. Although all people at the time were technically free and supposedly equal under the law, the vast majority remained segregated into their particular ethnic groups, with most of the wealth and power concentrated in the European American population.

The westward expansion of people with predominantly European ancestry entered regions that had been part of the Spanish conquest of North America, in a broad region encompassing what is now Texas, California, and the western states. Much of this region had previously been Mexican territory. Several states today retain their Spanish names, such as Colorado (colored), Nevada (snow covered), Montana (mountain), and Arizona (arid zone). Mating of Spanish colonists with Native Americans had been common, and their descendants generations later had settled throughout much of this part of North America. Today, most people with diverse ancestry that includes Native American and Spanish ancestry classify themselves as Hispanic or Latino.

Similar histories could be told for European colonialism nearly everywhere it happened. The perception of discrete races was the overall pattern because distinct populations of people were juxtaposed as a consequence of immigration. When viewed from a worldwide perspective, immigrants did not come from distinct races. However, when viewed from the limited vantage of newly established immigrant colonies, slaves transported from their homelands, and native populations that originally occupied the regions, the presence of distinct races seemed obvious, particularly to colonizers whose preconceived notions of their inherent racial supremacy were embedded in their worldviews, their religious beliefs, and their traditions.

The legacy of this sort of racial categorization remains today. One of the most important points that emerges from that legacy is the distinction between race as a social construct and race as a supposed genetic construct. As we've seen, racial classification makes little sense when viewed in a worldwide genetic context. DNA analysis has confirmed in abundant detail what was partially known from historical and archaeological evidence, which is that complex and massive migration events over the past four thousand years have spread DNA variants in a complex and diverse way throughout most of the
people of the world.
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The overwhelming majority of people on Earth have inherited a mix of variants tracing to major migration events such as these. As one anthropologist put it, “We're all mongrels, we've always been mixing,”
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Race as a set of social constructs, however, carries a very different meaning and importance than the notion of races as discrete genetic entities. The social constructs of race differ among nations as political categories because they are based more on the immigration histories of those nations than on worldwide genetic diversity. Recall the statement uttered in 1959 by the judge in the
Loving v. Virginia
antimiscegenation case cited in
chapter 1
: “Almighty God created the races white, black, yellow, malay and red, and he placed them on separate continents…. The fact that he separated the races shows that he did not intend for the races to mix.”
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Such a statement reflects more the perception of race as influenced by US immigration history than the complex genetic histories of people in Europe, Africa, Asia, and the Americas.

A good example of how racial classification is more social than genetic is the racial classification scheme of the US Census. The 2010 census first separated Hispanic classification from race by asking people to classify themselves as Hispanic or non-Hispanic. It then asked all respondents—regardless of their self-classification as Hispanic or non-Hispanic—to further classify themselves into one of the five following racial categories:

White – A person having origins in any of the original peoples of Europe, the Middle East, or north Africa.

Black or African American – A person having origins in any of the Black racial groups of Africa.

American Indian or Alaska Native – A person having origins in any of the original peoples of North and South America (including Central America) and who maintains tribal affiliation or community attachment.

Asian – A person having origins in any of the original peoples of the Far East, Southeast Asia, or the Indian subcontinent including, for example, Cambodia, China, India, Japan, Korea, Malaysia, Pakistan, the Philippine Islands, Thailand, and Vietnam.

Native Hawaiian or Other Pacific Islander – A person having origins in any of the original peoples of Hawaii, Guam, Samoa, or other Pacific Islands.
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People who classified themselves into the American Indian or Alaska Native, Asian, and Native Hawaiian or Other Pacific Islander categories were further asked to subclassify themselves. American Indian or Alaska Native respondents were asked to name their tribal affiliation, Asian respondents were asked to name the country of their ancestral origin, and Native Hawaiian or Other Pacific Islander respondents were asked to name the island of their ancestral origin. No such subcategorization was requested for the White and Black categories.

This lack of subcategories for Black and White does not reflect a lack of genetic diversity; people who self-categorize as Black and White ethnic groups in the United States are genetically diverse. Subcategorization in these groups, however, is mostly impossible and has little meaning. Large proportions of people who self-classify into these groups cannot identify a specific country or a specific region for their ancestry, often because some of their immigrant ancestors entered the Americas many generations ago, and their lines of ancestry often trace to various countries. In other categories, however, a relatively large number of people are themselves immigrants or are the recent descendants of immigrants and can thus trace their ancestry to a particular location.

During the twentieth century and into the twenty-first, worldwide immigration from various parts of the world has vastly diversified the populations of many nations. Diversity in the United States, for instance, is far greater now than it was a century ago. And diversity continues to increase. Taboos against antimiscegenation have lost the prominence they once had, although they most certainly have not disappeared. The once-distinct lines of segregation have gradually started to blur.

Race as a social construct is real and meaningful. According to Pilar Ossorio, professor of law and bioethics at the University of Wisconsin and an expert on both social and biological aspects of race,

Race is deeply rooted in the consciousness of individuals and groups, and it structures our lives and our physical world in myriad ways. It is a strong predictor of where people live, what schools they attend, where and how their spirituality is practiced, what jobs they have, and the amount of income they will earn. Race is real because human beings continually create and recreate it through the process of racialization.
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However, race as a social construct is neither universal nor constant. It varies depending on historical, social, and political norms. For instance, apartheid laws in South Africa classified Bantu and Khoisan people into different categories (Black and Coloured, respectively), whereas the US Census defines all people “having origins in any of the Black racial groups of Africa” simply as Black. The social constructs of race can also change over time and across different contexts. As Ossorio explains,

There is no unitary definition of race, no definition that applies in all places, at all times, and for all purposes. Scholars who include race as a variable in their studies must operationalize the concept of race in a manner that meets the needs of their study, while acknowledging that such “working definitions” merely “fulfill the need for an analytical strategy, they do not reflect a fixed social or biological reality.”
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Though it may be tempting to promote the utopian ideal of a truly “colorblind” world where race has nothing to do with social, political, or economic status, such an ideal is unrealistic—at least, in today's world and in the foreseeable future. The legacy of past and current racism is powerful and overwhelming. Though enforced racial segregation is no longer legal in the United States, racial distinctions for neighborhoods remain evident in every major US city, and such distinctions are often correlated with economic status. The fact that public schools in the United States are governed and funded largely by geographic location ensures that racial inequality in basic education will persist in spite of efforts targeted at its mitigation. Inequality in employment, public services, healthcare, and many other aspects of society persist and are strongly correlated with racial classification, often as a remnant of past discrimination.

Recognizing how modern perceptions of race arose as artifacts of immigration history, rather than as any sort of definable genetic boundaries or biological basis for race, is essential for understanding what race is and what it is not. Shifting the perception of race away from the notion of a genetic construct and toward the reality of a social construct is critical for what will continue to be a long battle toward eventually defeating racism and purging its legacy.

The evidence we've discussed reveals how the human species has evolved since our African origin and how people ultimately spread to occupy the habitable world. The evidence in our DNA shows that genetically we all are strikingly similar to one another. The common chimpanzee, though its natural range covers just a small part of west-central Africa, is genetically more diverse among its populations than are human populations spread across the continents of the world.
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As humans, we are all closely related—members of the same family, tracing our origins to a common homeland in Africa.

Because its focus is on science, this book has touched only briefly on the history of racism. A full exploration of that history chronicles some of the most unspeakable acts of mass torture and cruelty ever inflicted upon people. The atrocities of centuries-long racial persecution have for too long been sanitized from histories, and many people are unaware of this horrific side of human behavior during the past five centuries. The tide has turned, and a number of well-written, candid, and detailed accounts of the history of racism are now available as books, websites, and documentaries. They deserve a prominent place in historical accounts, complemented by scientific evidence of the type presented here. The history of racism must never be forgotten and should be a principal motivation for the ongoing battle to overcome its legacy.

That history includes a period when proponents of white supremacy used supposed science to promote their cause. A movement now called “scientific racism” was most influential during a period lasting from the mid-nineteenth to the late twentieth century, lingering to some degree even today. Part of its purpose was to preserve the view that nonwhite people were members of distinct races, separate and subordinate to the white race, even to the point where, according to some, nonwhite races did not merit inclusion within the human species. Hypotheses collectively known as
polygenism
posited separate biological origins of different races, an extreme and early version of the multiregional
hypothesis of human origins. To some, each race was considered as a separate and distinct species, with only the white race classified as human. Often, proponents mixed Christian theology with their supposedly scientific speculations to claim that Adam and Eve were the original parents of only the white race, other so-called races having allegedly evolved from animals. Under such a scheme, nonwhite people were legally classified as property, just as domestic animals were regarded as property under the law.
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This belief was one of several used to justify slavery and to deny human rights, and it supported an economic empire of slavery and racial subjugation. Eugenic and antimiscegenation laws, promoted as science, outlasted slavery by a century and often longer, persisting even into the late twentieth century in some places. There are those who still believe that notions of racial purity are biologically and theologically sound, and therefore desirable, in spite of the fact that current genetic evidence has obliterated all justification for such notions.

Some argue that DNA evidence of the type highlighted in this book reinforces rather than invalidates traditional racial classifications. As a recent example, Nicholas Wade, in his book
A Troublesome Inheritance: Genes, Race and Human History
, writes,

Even when it is not immediately obvious what race a person belongs to from bodily appearance, as may often be the case with people of mixed-race ancestry, race can nonetheless be distinguished at the genomic level. With the help of ancestry informative markers,…an individual can be assigned with high confidence to the appropriate continent of origin. If of admixed race, like many African Americans, each block of the genome can be assigned to forebears of African or European ancestry. At least at the level of continental populations, races can be distinguished genetically, and this is sufficient to establish that they exist.
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The ability to distinguish African and European DNA segments in African Americans does not imply the existence of discrete races when the distribution of human genetic diversity is considered on a worldwide basis. It reflects, instead, the historical juxtaposition of people whose ancestral backgrounds trace to the discontinuous places of western Africa and northern Europe as a consequence of European colonization and the Atlantic slave trade in North America.

Given the vast amount of human genetic information currently available, traditional racial classifications constitute an oversimplified way to represent the distribution of genetic variation among the people of the world. Mutations have been creating new DNA variants throughout human history, and the notion that a small proportion of them define human races fails to recognize the complex nature of their distribution. A large proportion of variants are very ancient, having arisen more than one hundred thousand years ago in Africa when all people lived there, and are now spread throughout the worldwide human population. These variants have been dispersed over tens of thousands of years as people migrated in myriad ways within Africa, out of Africa, back into Africa, and across the other habitable continents. Other variants display clinal patterns, gradually decreasing in prevalence from a central region. They originated in that region and then were dispersed in people who, over generations, migrated away. Yet other variants tend to be clustered in particular regions, often when barriers such as oceans or mountain ranges inhibited their dispersal during periods of history when people were unable or unlikely to migrate across those barriers. Furthermore, natural selection has resulted in increased prevalence of particular variants in certain parts of the world when those variants conferred an advantage for survival and reproduction. Variants influencing pigmentation or resistance to infectious diseases are prominent examples. In addition, the degree of human genetic diversity varies throughout the world and thus cannot provide a reliable way of classifying humans into particular races on the basis of how much or how little diversity is present. Not surprisingly, genetic diversity is highest by far in sub-Saharan Africa where humans originated. Last, widespread human mobility over the past several millennia has reshuffled the world's genetic diversity in complex ways, negating simplistic preconceptions of so-called pure and mixed races.

The concept of distinct human races as biologically valid groupings was widely accepted prior to the latter part of the twentieth century. It is now outdated, replaced by the more complex and scientifically reliable characterization of genetic ancestry. Some who still cling to the idea of genetically defined races cite evidence that some ancestry informative markers tend to cluster with one another in correlation with geography. Noah Rosenberg of the University of Michigan and his colleagues have conducted some of the
most extensive research on such clustering and have made it clear that “our evidence for clustering should not be taken as evidence of our support for any particular concept of ‘biological race.'”
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Notably, some of the world's most prominent human population geneticists have publicly criticized the people who claim genetic research supports the notion of biological races, and the unfounded inferences derived from that notion.
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Why should an accurate understanding of our genetic unity and diversity matter? First, there are practical reasons. Variations in health are, in part, a consequence of variations in our DNA. The tendency, however, to associate particular medical conditions with race is often overly simplistic and scientifically flawed. A number of genetic conditions, such as cystic fibrosis and sickle cell anemia, are more prevalent in people whose ancestry traces to particular parts of the world, but conditions such as these are not confined to a particular group, and they are rare in all groups. They should never be labeled as racial diseases.

Dealing with health-related susceptibilities is complex. Genetically inherited differences in skin pigmentation, for example, are inversely correlated with susceptibility to malignant melanoma, the most deadly form of skin cancer. Those with less skin pigmentation are more susceptible than those with greater skin pigmentation. Seemingly racial differences for other susceptibilities, however, may have a much greater social than genetic foundation. Susceptibility to alcoholism in Native Americans, for instance, may have more to do with poverty and poor living conditions than with genetic ancestry.

In this context, race or ethnicity as a social construct can have medical significance. Differences in socioeconomic status, education, quality of healthcare, health practices, substance abuse, infectious disease, and other nongenetic factors may be responsible for at least some of the difference in health conditions among socially defined ethnic groups. In such cases, efforts to overcome poverty, unemployment or underemployment, and educational inequalities are likely to have a commensurate effect on improving overall health.

The same can be said for educational attainment. So-called racial differences in IQ scores are more a consequence of disparities in socioeconomic status and the quality of education than of any genetic differences between ethnic groups. Efforts to improve educational quality and opportunity can increase the economic benefits associated with increased educational achievement.
As an educator who often works with first-generation college students, I have seen firsthand the transformation that a well-designed education can generate for those who are economically disadvantaged or lack an adequate educational background.

Beyond the practical reasons, there are perhaps equally important reasons why a scientifically based understanding of human diversity matters. It dispels notions of racial superiority and evokes a sense of wonder and respect for the variety, both genetic and cultural, of the world's human population, from our African origins to the present. Perhaps most important, it tells us who we are and how we originated.

Unfortunately, many people find it difficult to accept what current science tells us about the myth of race. It runs counter to what seem to be obvious racial distinctions, mostly in parts of the world where immigration history has juxtaposed people with discontinuous ancestral backgrounds in the same place. The racial categorizations that many of us have experienced throughout our lives have likewise inculcated a sense of racial division that is not easy to abandon. Regardless of what the scientific evidence shows, the perception of race and the associated racial discrimination are unlikely to disappear anytime soon. Furthermore, a scientific understanding of human evolutionary history challenges commonly held religious beliefs that are based on literal interpretations of biblical history. Everything we have discussed in this book, and everything related to human genetic diversity, is a consequence of our evolutionary history, supported by abundant evidence. Just as geneticist Theodosius Dobzhansky famously affirmed that “nothing in biology makes sense except in the light of evolution,” nothing we know about human genetic diversity makes sense except in the light of human evolution.
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Yet a significant minority of people (42 percent in the United States, according to the most recent Gallup poll) fully reject human evolution, opting instead for the belief that humans were specially created with no prior evolutionary ancestry less than ten thousand years ago.
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Such beliefs are often infused with a nonscientific perception of different races and how they supposedly originated. And, in spite of overwhelming scientific evidence and changing social norms, a relatively large proportion of people still cling to past traditions of white supremacy and racism.

To understand who we are as a species, and why we vary as we do, we must examine our genetic diversity in the context of a common African origin, followed by intra- and intercontinental diasporas that transpired over a period of tens of thousands of years, culminating in an era of major migrations that reshuffled the worldwide human genetic constitution over the past several thousand years and is still underway. Last, we must recognize that today's human population is far larger, more diverse, and more complex than it ever has been. We are all related, more than seven billion of us, distant cousins to one another, and, ultimately, everyone is African.