Until recent times, most people made their living growing crops, tending gardens, and raising animals. Some owned their own land, whereas others were tenant farmers or farmworkers, working on land that belonged to someone else. Whether wealthy or impoverished, most people were familiar with farm animals and were well aware of different types of these animals, which they often referred to as belonging to different races. For example, Charles Darwin uses the term race forty-three times in chapter 1 of his best-known book, On the Origin of Species, first published in 1859. On a few occasions he writes of racehorses, but in every other instance, his use of the word race denotes a genetically distinct group of animals or plants. The following sentence is a case in point: “When we look to the hereditary varieties or races of our domestic animals and plants, and compare them with species closely allied together, we generally perceive in each domestic race, as already remarked, less uniformity of character than in true species.”6
Interestingly, only three times throughout the entire book does Darwin refer to humans with the word race. In one instance, for example, he recognizes the ignorance in his day regarding the cause of human variation: “But we are far too ignorant to speculate on the relative importance of the several known and unknown laws of variation…. I might have adduced for this same purpose the differences between the races of man, which are so strongly marked.”7
In the nineteenth century, race denoted a broad grouping of related types of animals, whereas the term breed designated a more specific subgrouping, although there was much overlap between these two terms in practical use. For example, bulldogs, poodles, shepherds, hounds, terriers, and retrievers might be considered different races of dogs, whereas distinct subgroups within a race, such as bloodhound, coonhound, basset hound, greyhound, dachshund, and beagle, were (and are) considered different breeds of hounds. In modern usage, the term race has mostly disappeared as a designation for animals. The American Kennel Club, for instance, refers to hounds collectively as a group, not a race.8
The key distinguishing feature of both breed and race in animals is the ability to breed true, which means that individuals of the same breed or race consistently and predictably produce, generation after generation, offspring of the same type. For example, when two basset hounds mate, all their offspring consistently and predictably have the characteristics of basset hounds, such as long floppy ears, loose sagging skin, short legs, a relatively long body, short hair, and a baying bark typical of hounds. The term purebred is used to denote animals certified as members of a particular breed who do not have any recent ancestry from another breed, as documented by well-kept pedigree records. Animal keepers often take great care to ensure that the animals they raise are purebred, and that these animals mate only with members of the same breed, because purebred individuals typically command higher prices at market. A purebred horse with a known pedigree is much more valuable than one without. For dogs, pedigreed purebred puppies command high prices, whereas it is often difficult to find homes for mixed types.
When members of different breeds mate, their first-generation offspring often have a uniform appearance intermediate between their parents for some traits but more closely resemble one parent for other traits. These offspring are known biologically as hybrids, and when two hybrids mate, they often do not breed true. Instead, their offspring tend to vary in the traits they display. Darwin noted this phenomenon in the Origin of Species when he wrote, “The slight degree of variability in hybrids from the first cross or in the first generation, in contrast with their extreme variability in the succeeding generations, is a curious fact and deserves attention.”9 He recounted in this passage a phenomenon that animal and plant breeders had known for centuries: the uniformity of hybrids and the variability of their offspring, or, in other words, the inability of hybrids to breed true.
It is no surprise that throughout the past several centuries, people have used the term race to describe groups of people in much the same way it was used in past centuries to describe groups of animals. People with ancestry from a particular region of the world tend to share certain inherited physical characteristics, such as similar facial features and eye, hair, and skin pigmentation. The children of parents with similar regional ancestry typically inherit similar features, resembling their parents. However, the children of parents with substantially different ancestral backgrounds often have an appearance that is intermediate between that of their two parents. And in subsequent generations, the offspring may vary.
In part because of the obvious similarities between animals and humans for how traits are inherited, and in part because of cultural, political, and religious traditions, notions of racial purity and superiority have surged and ebbed yet persisted, crossing the boundaries of culture, geography, politics, and time. They are still with us today, and some of the most insidious actions based on notions of racial supremacy happened not long ago. They were the foundation of two related movements that became codified into law in various places and times: the eugenics movement and antimiscegenation.
In 1883, Francis Galton coined the term eugenics to denote the intentional genetic improvement of humans, much like the intentional breeding of animals and plants. The idea of direct selective breeding of humans was appalling to most, but discouraging or legally preventing people from procreating who were considered genetically unfit seemed much more acceptable. The eugenics movement thrived on a universal undercurrent of the supposed inherent superiority of the “white race”—people whose ancestry was northern European, British, or Scandinavian. Books and articles endorsing eugenics proliferated. For instance, Reginald Punnett, a famous British geneticist, wrote in 1913, “By regulating their marriages, by encouraging the desirable to come together, and by keeping the undesirable apart we could go far towards ridding the world of the squalor and the misery that come through disease and weakness and vice.”10
The first eugenics laws in the United States requiring mandatory sterilization of people considered unfit to reproduce were implemented in 1907, and between 1910 and 1930, many US states and European countries instituted laws mandating involuntary sterilization of people in prisons and mental institutions. Along with mandatory sterilization laws came antimiscegenation laws prohibiting interracial marriages, usually defined as marriages between “whites and nonwhites” or “whites and coloreds,” in an attempt to maintain the purity of the so-called white race. Under the guise of eugenic improvement and racial purity, and what the implementation of eugenic measures could supposedly do to improve human society, notions of racial superiority continued in popularity, but with a purported scientific foundation.
The worldwide popularity of the eugenics movement expanded during the first decades of the twentieth century, reaching its climax under the Nazi regime in the 1930s and ‘40s. A fundamental tenet of Nazism was the superiority of the so-called Nordic class of the Aryan master race, typified by light skin and hair, blue or green eyes, and Germanic origins, presumed to be associated with superior intellect and physical prowess. The Nazi regime exterminated millions of people because their genetic background was classified as subhuman (Untermenschen, literally “under-men”) and they were deemed a threat to the Aryan race. The majority of those who were killed were European Jews, approximately six million, although Roma (gypsies) and Slavic people, mostly Polish and Russian, were also killed, as well as people designated as homosexual and those with mental disabilities.11
Lesser known, but likewise intended to preserve and increase genetic integrity and superiority, were the Nazi antimiscegenation laws and the Lebensborn program. The antimiscegenation laws were part of the Nuremberg laws, which initially were anti-Semitic, defining people with four German grandparents as German, those with three or four Jewish grandparents as Jewish, and those with one or two Jewish grandparents as Mischling, meaning mixed or half-breed. The laws were complex but essentially required racial classification of people and discriminated against those considered non-Aryan. These laws were event
ually extended to discriminate against gypsies and black Africans as unsuitable for marriage with a person defined as German.
The Lebensborn (wellspring of life) program was a secretive Nazi effort to develop a superior human race through direct and intentional human breeding. Instituted at the same time as the Nuremberg laws in 1935 and managed by Heinrich Himmler, the program aimed to identify women and men considered to be racially pure Nordic Aryans—mostly young women who applied to the program and passed the racial superiority screening test and SS soldiers who served as the biological male parents. Himmler decreed that SS soldiers should father as many Lebensborn children as possible; marriage was not required. The children were to be raised in Lebensborn homes, furnished with loot from Jewish homes. As many as 17,500 children were born under the program, most placed with adoptive families after the war.12
As these secret actions were uncovered after World War II, eugenics laws fell into disrepute and were eventually repealed or left unenforced. By then, however, more than sixty thousand people had been involuntarily sterilized in the United States under such laws.13 Although some antimiscegenation laws were repealed, many remained in force well after the end of World War II, a result of belief that racial purity should be maintained. In the United States, the legality of those laws came to a dramatic and definitive end in the Supreme Court case Loving v. Virginia, recounted at the beginning of this chapter.
Antimiscegenation and eugenics laws stem from the notion that superior racial purity should be preserved, similar to maintenance of genetic purity in breeds of domesticated animals. Although similar patterns of inheritance are evident in animals and humans, there are some crucial flaws in assuming that breeds of animals equate to so-called human races. First, humans have intentionally bred domesticated animals to achieve the true-breeding characteristics that purebred animals have, resulting in extremes of variability among breeds—and uniformity within them—that vastly exceed the extremes of natural variation in humans. In dogs, for example, Chihuahuas and Great Danes differ by extremes in size, variation that far outweighs the outward variation among humans, and those extremes are a direct result of intensive breeding. Although restrictions on mating have been a part of various human cultures for most of history, humans have never been subjected to the type of intense selection for extreme types that is typical in animal breeding. Geographic proximity and cultural traditions—not intentional breeding—have historically been the most powerful factors influencing choice of mates in humans.
A second flaw in equating human races to animal breeds is that, historically and especially in modern times, humans have been a highly mobile species. Although some degree of historic reproductive isolation is responsible for part of the geographic distribution of genetic diversity in humans, there is evidence in our DNA that major and complex human migrations have dispersed, and continue to disperse, much of the genetic diversity in our species.14
These and other factors have ensured that the lines separating the worldwide geographic groups of humans are so blurred they are impossible to define. Harvard professor and geneticist Richard Lewontin describes his perception of the situation quite succinctly:
Racial classification is an attempt to codify what appear to be obvious nodalities in the distribution of human morphological and cultural traits. The difficulty, however, is that despite the undoubted existence of such nodes in the taxonomic space, populations are sprinkled between the nodes so that boundary lines must be arbitrary.15
The article by Lewontin from which this quote is extracted bears the title “The Apportionment of Human Diversity,” and it is one of the most foundational and misconstrued articles ever published on the biological basis of race in humans. Before the 1960s and ‘70s, scientists had few methods available to confidently examine genetic diversity among people. They based estimates of diversity largely on appearance, making assumptions about how much diversity was inherited and how much was a consequence of nongenetic, often termed environmental, variation. Moreover, much of the assessment of human diversity was biased, as Lewontin puts it, by “those characters to which human perceptions are most finely tuned (nose, lip, and eye shapes, skin color, hair form and quantity).”16 Variation for such traits represents only a small subset of overall human genetic diversity, and they are used for classification largely because they are the varying characteristics our brains are attuned to most readily recognize—and those we consciously or unconsciously associate with the geographic ancestries of different people. Other outward characteristics that vary among people do not fall neatly within traditional racial categories.
Adult body height, for example, is genetically determined to a large extent, and it varies considerably among people from all regions of the world. If we were to segregate people by height, there would be little association along traditional lines of racial classification. The tallest people in the world, on average, are the Dutch, and among the tallest are the Masai of East Africa. Several indigenous groups living in tropical regions of the world are substantially shorter on average, including the Mbenga, Mbuti, and Twa of Africa; the Andamanese, Aeta, Batak, Rampasasa, Semang, and Taron of south and Southeast Asia; the Djabugay of Australia; and the Yąnomamö of Amazonian South America. The genetic basis for some of these extremes in stature has been well documented and is likely a consequence of natural selection.17 Clearly, these variations in height do not mirror traditional racial or geographic classification schemes.
As another obvious example, pattern baldness is a common inherited trait that varies among people (mostly in men and to a lesser extent in women) whose ancestries trace to various parts of the world. Although readily visible, and less prevalent in certain regions of the world than in others, variation for pattern baldness has never been a criterion for racial classification. It makes no sense to lump those with pattern baldness into one racial classification and those without it into another. Only a subset of genetically determined traits that vary in humans is correlated with geographic regions of ancestry.
Other inherited characteristics that are not outwardly apparent, such as blood types and other biochemical traits, vary among people. It is, of course, impossible to tell simply by looking at someone what her or his blood type is, but it is possible to precisely identify blood types and other inherited biochemical traits through laboratory analysis. By the 1970s, scientists had developed methods that allowed them to quantify some of this unseen genetic diversity with exceptionally high accuracy. Lewontin asked whether such biochemical diversity was correlated with traditional racial classifications. In other words, were the physical variations people tend to associate with different races borne out in the precise genetic variations scientists could measure in the laboratory?
His conclusion was shocking—unexpected in its magnitude—and has shaken the foundation of racial classification ever since its publication. Lewontin examined data from seventeen different genes in people classified into seven groups by geographic origin, as named in his article: Amerinds, Australian Aborigines, Black Africans, Caucasians, Mongoloids, Oceanians, and South Asian Aborigines. He found that the degree of genetic variation within each group exceeded that between different groups. In other words, people within a particular racial group varied more among themselves than their overall group varied from other groups. On average, according to his calculation, 85 percent of overall genetic diversity fell within groups, whereas only 15 percent could be attributed to between-group differences. He also noted that “the difference between populations within a race accounts for an additional 8.3%, so that only 6.3% is accounted for by racial classification.”18
As an example, A, B, AB, and O blood types vary within the groups identified by Lewontin, albeit not in the same proportions within each group. For instance, all four types are present within the European group and the African group, with type O being the most prevalent within both groups, albeit more prevalent within the African group. Because all four types are present within both groups, a person w
hose ancestry is European might be incompatible as a potential blood donor for another person with European ancestry, whereas a person with African ancestry may be a compatible donor. In fact, blood banks in hospitals currently identify blood based only on biochemical blood typing, with no reference to racial identification of donors (although this has not always been the case).19
Lewontin's analysis rapidly gained popularity, for it seemed to provide a scientific case against a biological basis for racial inequality, and the political timing was right. When Lewontin's article was published in 1972, the civil rights movement in the United States had by then gained considerable political support and was a frequent issue in the news. Lewontin's article was often cited then, as it is now, as evidence that there is scant scientific basis for racial classification. Such classification was said to be more social than biological.
Thus, it was quite a turnaround in 2003 when Cambridge University professor A. W. F. Edwards, one of the world's foremost statisticians and population geneticists, published a counter-article titled “Human Genetic Diversity: Lewontin's Fallacy.” Edwards makes it clear that “there is nothing wrong with Lewontin's statistical analysis of variation, only with the belief that it is relevant to classification.”20 Edwards points out that Lewontin examined each of seventeen genes independently, but that an assumption of independence was unwarranted; variation for one gene may be correlated with variation for another, and such correlations must be taken into account when using such data for classification. As a simple example, Edwards points to a common practice in anthropology of measuring the length (back to front) and breadth (side to side) of skulls. It is possible to focus on length and breadth independently and determine variation for each among human skulls without reference to the other. But doing so misses the important point that the two are correlated; an increase in overall skull size results in a concomitant increase in both length and breadth. Edwards then highlights a number of studies of human genetic diversity that take such correlation into account. The correlation is essential for describing human genetic diversity and systems intended to classify such diversity.
Everyone Is African Page 2
