Race and Physical Differences

Everyone recognizes race. Africans, Europeans, and Asians can be distinguished at a glance because the races differ so obviously from each other. Although the differences are popularly referred to as “skin color,” as if this were where they began and ended, color is one of the least important ways in which the races differ.

Although many physiological differences are well established and easy to measure, they are often completely unknown to the general public. Perhaps this is because the cumulative effect of a list of physical differences can give an impression of alienness even more powerful than do assertions about mental differences.

Just as it was once universally accepted that races differ in intelligence, so the study of physical differences was once entirely respectable. Some 19th century investigators, however, hoped to find justifications for slavery and not all were good scientists. Therefore, in the revolt against “racism,” good data from the past has been thrown out along with the bad, and the study of physical differences has languished.

The modern data now becoming available confirm many 19th century views. The best evidence suggests that races differ markedly in such things as maturation rate, brain size, bone density, susceptibility to disease, and perhaps even personality.

The races differ in skin color because of different levels of melanin production. All races have approximately the same number of melanocytes, or melanin-making cells, but they differ in how actively the cells make melanin.

Anyone who has seen an albino African knows how trivial a racial difference skin color really is. The albino may actually seem more strange to a European than a normal African, because negroid features and tightly curled hair seem incongruous in a light-skinned person. No one would mistake the albino for a European. Likewise, West Africans, Dravidian Indians, and Australian aborigines are all “black,” but they are racially very different.

Color does have one physiological effect: three and a half times as much ultraviolet light from the sun passes through the skin of whites as through that of blacks. Light skin is beneficial in the northern regions where whites evolved, since ultraviolet light converts ergosterol in the body into vitamin D. Dark skin protects against the tropical sun.

Adaptation to Climate

There are other racial characteristics that are obviously adaptations to the climates in which the races evolved. Many East African peoples have elongated limbs and bodies that easily dissipate heat. North Asians, on the other hand, have evolved in a cold climate. Their bodies are more squat, they have thick, dark hair, and the epicanthic fold that gives Asians almond-shaped eyes is thought to reduce glare from snow and ice. A flat nose is less exposed to cold, and the virtual absence of facial hair means that condensation from a man’s breath will not freeze on his beard and chill his face. All of these characteristics are most obvious in the Asians who live in the coldest climates.

Some racial differences are not so easily explained. Phenylthiocarbamide (PTC) is a chemical that can be synthesized in the laboratory. To some people, it has a strong, bitter flavor, but to others it has no flavor at all. Seventy percent of Australian aborigines can taste PTC, but only 13 percent of Navaho Indians can. Fifty percent of whites and about 38 percent of Japanese can taste it.

For whatever reasons, the races do not smell the same. Blacks and whites have strong, but differing smells, and many Asians have scarcely any smell. Koreans often have no odor-producing glands in their arm-pits at all and Japanese have very few. Nineteenth-century Japanese found Europeans so foul-smelling that even today, a common Japanese expression for anything Western means “stinking of butter.”

Though they may not always be willing to say so, sports physicians have found physical differences that give different races advantages in different sports. Whites and West Africans, for example, differ in proportions of body fat, width of hips, thickness of thighs, bone density, and proportion of fast- and slow-twitch muscle. Even East and West Africans differ in important ways that explain why they excel in different sports.

Because blacks have such dense bones, they are less buoyant and less likely to be swimming champions. However, their bones are more resistant to aging. After their mid-30s, white men lose about 2.5 percent of their bone mass every year. Blacks lose less than one percent. Loss of bone mass speeds up greatly under conditions of weightlessness, so blacks could probably survive longer space voyages than whites.

Studies have repeatedly found that black men have more of the male hormone testosterone in their blood than whites do. Testosterone is directly related to physical and sexual aggressiveness, but it also combines significantly with intelligence. Men who are intelligent but who have high testosterone levels are likely to be more successful, socially and professionally, than intelligent men with low testosterone levels. Men who are unintelligent but who have high testosterone are more likely to be criminals than unintelligent men with low testosterone. High crime rates among blacks are consistent with low intelligence and high testosterone.

Although egalitarian partisans — most notably Steven Jay Gould in his 1981 book, The Mismeasure of Man — have tried to discredit the evidence, it is well established that average brain size differs from race to race. A study by K. L. Beals, published in Current Anthropology in 1984, reported that a survey of 20,000 skulls shows that the average size of the brain case in Asia is 1380 cc, while in Europe it is 1362 cc and in Africa 1276 cc. Other studies have found that the brains of American blacks are approximately eight percent lighter than those of American whites.

Studies of brain size and weight can be difficult to replicate because researchers do not often have access to enough skulls or cadavers and may use different measuring techniques. A 1989 study overcame these difficulties by using magnetic resonance scanning to determine skull capacity. Brain size was found to have a positive correlation of about 0.3 with intelligence.

Not surprisingly, the bones within which brains reside can be markedly different. A child could distinguish between the skulls of Eskimos and Laplanders as easily as he could tell cucumbers from zucchinis. The skulls of Australian aborigines have characteristics not found in any other race, but common in fossils of pithecanthropus. The bones of the skull are twice as thick as those of any other race (10 mm v. 5 mm), and the skull has heavy frontal and parietal ridge lines typical of pithecanthropus. The teeth and lower jaws of aborigines are also larger than those of other races, and more similar to those of our remote ancestors.

It is little known that Africans have identical twins twice as frequently as Europeans — who in turn have them twice as frequently as Asians. Some African populations have identical twins seven times as frequently as whites. Blacks also have shorter gestation periods than whites or Asians. By the 39th week, 51 percent of black babies have been born but only 33 percent of whites. By the 40th week, the figures are 70 percent and 55 percent. Shorter gestation seems to be a characteristic of blacks that is independent of social status or access to medicine.

Prof. J. Philippe Rushton of the University of Western Ontario, who has probably studied maturation rates more extensively than anyone else, reports that rapid development of blacks continues after birth. Many African and black American newborns can hold their heads up whereas white and Asian newborns almost never can. The average age at which black children walk is 11 months, compared to 12 months for whites and 13 months for Asians.

Prof. Rushton has found that blacks reach sexual maturity earlier than whites. By age 12, 19 percent of black girls have full development of breasts and pubic hair, whereas only two percent of white girls do. Black American women menstruate at an earlier age than white women. They then go on to have sexual intercourse for the first time at an average age that is two years younger than that of whites.

Although it has long been the subject of ribald speculation, the races do appear to differ in the size of their sex organs. The best data seems to have been gathered in 1979 by P. H. Gebhard and A. B. Johnson. They actually took measurements and found that popular myths are correct: blacks are better endowed than whites. In extensive interviews, they also found that black men at least report themselves to be less restrained than whites in their willingness to commit adultery, likelihood of frequenting prostitutes, and number of sexual partners.

Somewhat comparable differences have been found between whites and Asians. Even after controlling for body size, Danes have testes that are proportionately twice the size of those of Chinese. Whites are also estimated to produce twice the number of spermatozoa per day as Asians.

Earlier maturation and early sexual activity among blacks may have a biological price. In the United States, blacks, on average, can expect to die six years sooner than whites. Higher homicide, accident, and disease rates contribute to this difference, but it is entirely possible that blacks may also have a naturally shorter life span.

Medical Differences

Our society generally keeps quiet about physical differences between the races, but information about them occasionally surfaces in news stories about disease. Alcoholism, for example, appears to strike different races at different rates. Asians (and American Indians to whom they are related) react more strongly than whites to alcohol. More Asians than whites show an allergic reaction to alcohol and therefore do not drink, whereas many American Indians seem to have a biological predisposition to alcoholism. Curiously, Asians are twice as likely as whites to suffer from motion sickness.

In the United States, the most frequently reported medical differences concern blacks and whites. It is well known that only blacks suffer from sickle-cell anemia, for example, a condition that helps the body resist malaria, and is therefore a benefit in the African jungle.

Most of the known medical differences, however, seem to disadvantage blacks. Black women are twice as likely to have strokes as white or Hispanic women, and they suffer more damaging aftereffects. Blacks are three to four times more likely to have dangerously underweight babies. This could be due to bad diet, poor general health, or scant medical care, but some studies indicate that even when these factors are equalized, black babies are more likely to be underweight.

Kidney disease is eighteen times more common among blacks than whites. Left untreated, AIDS kills blacks more rapidly than it does whites or Hispanics, and blacks do not respond as well to the drug AZT as do patients of other races. Glaucoma strikes blacks five times more often than it does whites. It sets in earlier, and the likelihood of getting the disease does not appear to be affected by social status or availability of medical care.

Blacks are also twice as likely as whites to have high blood pressure, and five to seven times more likely to have dangerously high blood pressure. This is often attributed to the pressures of “racism,” but physiology is certainly part of the cause.

A study at the University of Maryland found that when black and white students were paired for age, diet, fitness, and medical history, and given a mild stress — their hands were put in ice for 30 seconds — blacks reacted by constricting their blood vessels (a hypertensive reaction) for at least ten times longer than whites. Research in Barbados has shown that mixed-race blacks are more likely to have high blood pressure if their maternal rather than paternal ancestors were African; genes passed down from the mother seem somehow to be involved. One reason for high blood pressure among blacks may be their relative inability to secrete sodium, so a salty diet can be more dangerous for blacks than for whites.

It has long been known that blood transfusions and organ transplants work best between people of the same race. Until the Second World War, stocks of blood were routinely segregated by race for this reason. Classification by race was ended when it was discovered to be “racist,” but blood banks are re-instituting segregation.

The distribution of the common blood types is different from race to race, and some rare types are unique to certain races. Only blacks have U negative blood; only whites have Vel negative or Lan negative blood. Dr. W. Laurence Marsh of the New York Blood Center justifies racial classification: “It makes no sense to screen 100,000 whites for U negative when no U negative white person has ever been found.”

Kidneys and other organs are classified by race for similar reasons. About 20 percent of blacks are so genetically incompatible with whites that they reject organs from all white donors.

Origin of Species

Clearly, all these differences cannot be dismissed with the fashionable notion that race is nothing more than a matter of skin color. No one knows for how long the different races have been evolving independently, but it might be necessary to go back one million years or more to find an ancestor common to all races. Clearly, a great deal of divergence has taken place during that time.

In his magisterial work, Race, John Baker suggests that certain racial groups are already so different from each other that they are not, technically speaking, the same species. Certain matings between extremely unrelated stocks — Bushmen and Europeans, for example — are thought to have produced only female children, or in some cases hybrids that could not mate successfully among themselves. These are well-known signs of an unrelatedness that is so vast as to be verging on separation into different species.

Indeed, according to Dr. Baker, in the prehistoric past different races and sub-races probably avoided cross-breeding and behaved as if they were different species. He points out that in nature, animals that are no more different from each other than northern Europeans and southern Europeans never breed with each other. It is only in domestication that a horse, for example, can be made to mate with a donkey. Man is, of course, the most domesticated of animals. As the French anthropologist Paul Broca remarked, “Man, especially civilized man, is of all the animals the least exclusive in his amours.”

Separate development is, to use Charles Darwin’s phrase, the origin of species. Apes and humans once had a common ancestor but are now distinct species. Likewise, racial differences are nature’s first steps towards the creation of new species. Left to themselves for long enough, the different races of man would have become so different that they could no longer produce fertile young. This might well have happened if the domesticating effects of civilization had come later, or if discovery and travel had not brought isolated peoples into contact with each other.

One of the great ironies of today’s quest for “diversity,” — the forcible mixing of peoples as unlike each other as possible — is that it is a destroyer of diversity. It is only through separation that nature can produce that culmination of true diversity: a new species.

Editor’s Note: This is the second essay in a series. We recommend Part I: Race and Intelligence: The Evidence and Part III: Racial Differences — Why They Matter.