Many AIMs have already been found. For some of them, the reasons for their presence on one continent but absence on another is readily apparent. One variant of the FY gene is ubiquitous in Africans but extremely rare among everyone else. The African variant is odd insofar that it prevents the protein that FY encodes from being made. Everyone else makes the protein, though its exact form can vary too. The FY protein is a growth-factor receptor found on blood cells, one that the malaria parasite seems to use as well, and its absence in Africans is almost certainly the result of long-standing natural selection for resistance to the disease. The absence of FY in Africans and its presence everywhere else has been known for decades. Many other differences are now being found – although they are usually not as dramatic as FY’s. No one knows what most AIMS do or why they are there.
Somewhere among all those AIMs, however, will be the genes that give a Han Chinese child the curve in her eyelid and a Solomon Islander his black-, verging on purple-, coloured skin. Among them, too, will be the genes that affect the shape of our skulls. Skull measuring has a long history in anthropology. One of the first really assiduous skull measurers was a Dutchman, Petrus Camper, who in the 1700s invented the ‘facial angle’ – essentially an index of facial flatness. In his most famous diagram, Camper shows a series of heads and skulls – monkey, orangutan, African, European, Greek statue – with ever-declining facial angles. Camper himself was no racist. In his writings he emphasised repeatedly the close relationship between all humans no matter what their origins. ‘Proffer with me,’ he urged in 1764, ‘a fraternal hand to Negroes and recognise them for veritable descendants of the first man, to whom we all look as our common father.’ To which he added that the first man may have been white, brown or black, and that Europeans are really just ‘white Moors’ – and did so at a time when Linnaeus was carving up our species.
Sadly, Camper’s iconography spoke louder than his words, and his diagram with its implicit demonstration of a hierarchy from ape to Apollo (with Africans rather closer to apes than to gods) became a staple of nineteenth-century anthropology. There is no need to recap and critique the craniometric studies carried out in the nineteenth and early twentieth centuries that sought to demonstrate that one subset of humanity was more or less intelligent than another – others have done so with a thoroughness that their scientific influence scarcely merits. But it is worth noting that modern physical anthropologists remain keen on describing skull shape, though nowadays they tend to do so with 3-d laser scanners and multivariate statistics. They find, perhaps unsurprisingly, that for all the variety within populations, people from different parts of the world have different-shaped heads.
Much as Camper claimed, the jaws of sub-Saharan Africans do protrude, on average, further from their foreheads than do the jaws of Europeans – an attribute known as ‘prognathism’. Melanesians and Australian Aborigines are also more prognathic than Europeans. Contra Camper, however, this does not make African (or Aborigine) skulls more like ape skulls than European ones. The facial angle is a rather crude way of capturing an exceedingly complex aspect of skull shape. It does not discriminate between different ways of being prognathic. A chimpanzee has a high facial angle because its whole face and forehead slope; Africans and Aborigines have slightly higher facial angles than Europeans because of a jut in the jaw alone. Besides, Europeans do not even have the flattest faces. That honour – if honour it is – must go to the Inuit of northern Canada.
Human skulls are wonderfully diverse. The Inuit are also notable for the largeness of their eye orbits and the massiveness of their cheekbones. Compared to everyone else, the Khoisans of southern Africa have bulging foreheads (frontal bossing); Australian Aborigines have massive brows (supra-orbital ridges); some sub-Saharan Africans have widely set eyes (large inter-orbital distances); Andaman Islanders (negritos) have small, round skulls – the list of differences could be extended indefinitely. Few of these differences are absolute. Just as most of the variance in gene frequency is found within, rather than among, populations (nations, continents), so too is most of the variance in skull shape. And the differences among populations are all subtle. Australian Aborigines and Inuit differ in prognathism by only 6 per cent. Small differences, then, but differences that, given the attention we devote to each other’s faces, strike us immediately.
VARIATION IN HUMAN SKULLS: LEFT TO RIGHT: AUSTRALIAN ABORIGINE, CHINESE, EUROPEAN AND KHOISAN. FROM ARMAND DE, QUATREFAGES 18822 Crania ethnica: les cranes des races humaines.
My claim that we will soon be able to identify the genes responsible for all this diversity in skull shape suggests an important question: namely, do such genes exist? In 1912 the American anthropologist Franz Boas set out to demonstrate that they do not. A humane and tolerant man, he was an implacable opponent of those who sought to make invidious distinctions between humanity based on the shapes of their skulls. The following passage, taken from a serious anthropological article written in 1905 by a German dentist called Rose, gives a flavour of what he was up against: ‘The long heads of German descent represent the bearers of higher spiritual life, the occupants of dominant positions, to which they are destined by nature, the innate defenders of the fatherland and the social order. Their whole character predetermines them to aristocracy.’ And so on, to the detriment of the more democratically minded and un-German ‘round heads’.
The ‘long’ and ‘round’ heads refer to the value of the ‘cephalic index’, the ratio of skull breadth to width (expressed as a percentage, long heads or dolichocephalics have a cephalic index below seventy-five, while round heads or brachycephalics have a cephalic index above eighty; mesocephalics are somewhere in between). Noting that the immigrants who arrived at Ellis Island – Bohemians, Slovakians, Hungarians, Italians, Scots and Eastern European Jews – varied somewhat in their cephalic indexes, Boas asked whether these differences were due to genetic (to use his terminology, ‘racial’) or environmental causes. He reasoned, soundly, that if the skulls of the American-born children of all these various groups were more similar to each other than those of European-born children, then environment rather than ancestry must be the cause of the differences. Boas measured some thirteen thousand heads – a vast undertaking that left him, in the absence of computers, overwhelmed by numbers. Nevertheless, he managed to produce a graph that seemed to show that the cephalic indices of the US-born children of Sicilians and Eastern European Jews (both rather dolichocephalic to begin with) were, indeed, converging. It was a case of new heads for the New World.
Boas’s study dealt a near-fatal blow to craniometry. Over the last ninety years it has been cited innumerable times – not least by the late Stephen Jay Gould – as proof that skull shape is ‘plastic’, that is, caused by non-genetic differences. Boas, however, was wrong. His data have recently been comprehensively re-analysed using modern statistical techniques. The skulls of American-born children do indeed differ from those of their parents, but they do so inconsistently. Indeed, had Boas chosen to compare the children of Scots and Hungarians, rather than those of Sicilians and Eastern European Jews, he could have shown that America causes skulls to diverge rather than converge in shape. But he was wrong in a deeper sense than this. Re-analysis of his data also shows that the changes in skull shape caused by American birth, whatever their direction, are trivial compared to the differences that remain and that are due to ancestry and family – or, to put it more succinctly, to genes. Indeed, looking beyond European immigrants, this is hardly surprising. Forensic anthropologists in the United States and Britain are quite adept at telling whether a given skull, perhaps evidence of some foul deed, once belonged to someone of African or European ancestry. That they can do so after decades, even centuries, of co-existence, not to mention generous amounts of admixture, suggests that our differences are not, as is often said, merely skin deep, but extend to our skulls – if not to what they contain.
So, genetic differences exist among all sorts of people. Should we try to find out wh
at they are? Many scientists think not. Some find it enough to dismiss such physical diversity as exists among human populations as ‘uninteresting’ – not worthy of study. Others concede that it may be interesting, but that it should not be studied, since even to contemplate doing so is to engender social injustice. They fear a revival of not merely racial, but racist, science.
For my part, I should love to know the genes responsible for human diversity; the genes for the differences – be those differences between men and women who live in the same village or those who have never trodden on each other’s continents. In part this is simply for the pleasure of knowing. This the pleasure that comes from looking at Gabriel Dante Rossetti’s painting La Ghirlandata and knowing that his model, Alexa Wilding, had two loss-of-function MC1R mutations that gave her such glorious red hair. This pleasure of knowing is partly that which all science gives, but to which is added the pleasure that comes from understanding the reason for something that has been hitherto at once familiar but completely mysterious.
The view that human diversity is dull seems to me excessively Olympian. After all, if population geneticists have ignored human variety, they have for decades lavished their (seemingly inexhaustible) energies studying variety in the colours of garden-snail shells and the number of bristles that decorate the backs of fruit flies – problems that are intellectually much like those presented by human variation.
The claim that human genetics is morally dangerous is a more serious one. One can certainly, given the history of racial science, see where such a claim originates. Nevertheless it is misplaced. Reasonable people know that the differences among humans are so slight that they cannot be used to undermine any conceivable commitment to social justice. ‘Human equality,’ to borrow a slogan of Stephen Jay Gould’s, ‘is a contingent fact of human history.’ What is true, however, is that as long as the cause of human variety remains unknown – as long as the 7 per cent of genetic variance that distinguishes people from different parts of the world remains obscure – there will always be those who will use that obscurity to promote theories with socially unjust consequences. Injustice can sometimes be the consequence of new knowledge, but more often – far more often – it slips in through the cracks of our ignorance.
Perhaps the most compelling reason that we should once again turn our attention fully to the study of human physical diversity is that it is disappearing. In South-East Asia the negritos, those enigmatic pygmy-like people, are in decline. They are hunter-gatherers. Overrun by Austronesian-speaking farmers in the Neolithic, they mostly persist on remote islands. Now, modernity threatens. On Lesser Andaman, the remaining Onge live in reservations. On Greater Andaman, a few hundred Jarawas survive by virtue of having fended off the curious with bows and arrows (in the last fifty years they have killed or injured more than a hundred people), but they too have now emerged from the forest, attracted by baubles offered by Indian officials. It is feared that they will soon succumb to tuberculosis, measles and culture shock as their predecessors have.
They are only the latest casualties of Austronesian and European (not to mention Chinese, Bantu and Harappan) expansion. In 1520 Ferdinand Magellan, arriving at the straits that today bear his name, reported the existence of a race of giants that lived in the interior of Tierra del Fuego. He called them the Pataghoni, after a giant in a Spanish tale of chivalry. Subsequent travellers embroidered the account; by 1767 these giants, a wild and brutal people, had grown to about three metres (ten feet) tall. Today, the giants of Tierra del Fuego are as forgotten and fantastical as Pliny’s Arimaspeans. And yet the Pataghoni existed. They called themselves the Selk’nam or Ona, and they had an average adult-male height of 178; centimetres (five feet ten inches) – giant, then, but only to sixteenth-century Spanish sailors. But if their stature was not that remarkable, their skulls certainly are. They have a strength and thickness, a robustness, which other human skulls don’t, and this is true of their skeletons as a whole. Some photographs of the Selk’nam exist. They depict a handsome and physically powerful people who wore cloaks made from the pelts of the guanacos that they hunted on foot using bows as tall as themselves. Argentine sheep ranchers killed the Selk’nam off in a genocidal slaughter, and the last one died some time around 1920.
GROUP OF SELK’NAM, TIERRA DEL FUEGO C.1914
There is one more thing I should like to know about. And it is a phenomenon more general and nearly as contentious as race. It is beauty. Beauty is that which we see (or hear or touch or smell) that gives us pleasure, and as such its forms are, or at least seem to be, infinitely various. Here I am concerned with physical beauty alone.
‘Beauty,’ says the philosopher Elaine Scarry, ‘prompts the begetting of children: when the eye sees something beautiful, the whole body wants to reproduce it.’ Plato, she points out, had the same idea. In The symposium, Socrates tells how he was instructed in the arts of love by Diotima, a woman of Mantinea, and how they spoke of the nature of love and beauty. ‘I will put it more plainly,’ says Diotima. ‘The object of love, Socrates, is not what you think, beauty.’ ‘What is it then?’ ‘Its object is to procreate and bring forth beauty.’ ‘Really?’ ‘It is so, I assure you.’
Darwin could not have put it better himself. Much of his The descent of man and selection in relation to sex is devoted to investigating the presence, perception and purpose of beauty. ‘The most refined beauty,’ he wrote, ‘may serve as a charm for the female, and for no other purpose.’ He was thinking of the tail feathers of the male Argus pheasant with its geometrical arrays of ocelli. But the psychologies of pheasants and Fijians are really much the same. For Darwin, the love of beauty is a very general evolutionary force, second only to natural selection itself in power. Creatures choosing beauty for generation upon generation have given the natural world much of its exuberance. Sexual selection has given the Madagascar chameleon its horns; it has given the swordtail fish its sword and Birds of Paradise and Argus pheasants their tails; it has given the human species its variety.
One of the fascinating things about Darwin’s account of beauty is that without reference to philosophers or artists he stakes out a position on the great issues of aesthetics. He wants to know whether or not beauty is universal or particular, whether it is common or rare, and whether or not it has meaning. To all of these questions Darwin has an unequivocal answer. Physical beauty, he asserts, is not universal, but rather particular. Different people in different parts of the world each have their own standard of beauty. And it is rare. To be beautiful is to be a little different from everyone else around us. It is also meaningless. Our brains, for whatever reason, perceive some things as beautiful, and do so regardless of the other qualities that those things may have. Beauty does not signify anything. It exists for its own sake.
Darwin’s views on beauty are characteristically, effortlessly, original. The descent of man contains nothing, for example, about the classical ideal of beauty – the ideal that, from Archaic kouros to Antinous’ scowl, was replicated across the Mediterranean for centuries as if there were a formula for it; which there was, one that by the Renaissance had become a theory of human beauty in which proportions were divine, a theory that in the eighteenth century turned into the standard by which all humanity was judged. It was this ideal that caused Winckelmann to assert that the ancient Greeks were the most beautiful of all people (though he thought modern Neapolitans comely as well); that caused Camper to place the head of a Greek statue at one end of his continuum of facial angles; Buffon to identify a ‘beauty zone’ between 20 and 35 degrees north that stretched from the Ganges to Morocco and took in the Persians, Turks, Circassians, Greeks and Europeans; and Bougainville, when he arrived in Tahiti in 1768, to eulogise its inhabitants in terms of a classical idyll painted by Watteau. Darwin avoids all this. He does not tell us what he thinks is beautiful; instead he attempts to find out what other people think. He collects travellers’ reports. American Indians, he is told, believe that female beauty consists of a broad, flat fa
ce, small eyes, high cheekbones, a low forehead, a broad chin, a hook nose and breasts hanging down to the belt. Manchu Chinese prefer women with enormous ears. In Cochin China, beauties have round heads; in Siam, they have divergent nostrils; Hottentots like their women so immensely steatopygous that, having sat down, they cannot stand up again.
Darwin does wonder about the quality of his data – and rightly so. But in general he is quite convinced that different people perceive beauty in different ways. His vision is an appealing one. Per molto variare la natur è bella – nature’s beauty is its variety; it could be Darwin’s slogan and it could be Benetton’s (though it was Elizabeth I’s). Indeed, when we consider the whirlwind of fashion it is impossible to doubt that the love of beauty is frequently the particular love of rare and meaningless things. Among scientists who study beauty, however – and the study of beauty is itself increasingly fashionable – Darwin’s views are seen as rather quaint. These days, most research on the subject begins with the notions that the standard of beauty is universal, that the presence of beauty is rather common, and that far from being meaningless, it has a great deal to say.
The universality of beauty’s standard is as self-evident as its particularity. The apparent contradiction is resolved if we simply recognise that there are some things about which tastes differ, and some about which they do not. Tastes in hairiness (cranial, facial, bodily), pigmentation (eye, hair and skin colour) and perhaps even body shape (hip–waist ratio) all seem to differ quite a lot from person to person, place to place, time to time. But the taste for relative youth – at least when men judge women – does not. Nor, it seems, does the taste for certain kinds of faces. Average faces seem to be universally more attractive than most, but not all, variant faces. Symmetry is preferred over asymmetry. These are some of the results of a large literature devoted to finding out who finds what beautiful when. Much of it demonstrates the obvious. After all, were a Papua New Guinea tribesman brought to London’s National Gallery and offered the choice of Botticelli’s Venus (she of Mars and Venus) and Massys’s Grotesque Old Woman as a mate, he might well be unimpressed by either, but we can be sure which one he’d choose.
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