Descent of Man, Pt. II

Before the Dawn by Nicholas Wade, chapters 4 & 5

I am going to keep my promise to keep my initial summary of these chapters very short in the hope that contributors to this discussion, more learned in evolutionary theory than I, will share much of the burden. The story Wade wishes to tell in these chapters is how humanity developed in Africa and how, some 50,000 years ago, our ancestors made their way out of Africa and spread across the face of the earth.

Chapter IV: Eden

Wade bases his genetic argument on research done on the Y chromosome and mitochondrial DNA, “the only two parts of the human genome that escape th shuffling of genetic material between generations.” The Y chromosome is carried by all men, and mitochondrial DNA by all humans. Mutations in the Y chromosome make it possible to divide men into groups. Since the form M168 occurs mostly in Africa, and since it is tentatively dated to 44,000 years ago, that gives a date before which the Exodus should have taken place. Parallel work on the click languages of Africa, which some linguists assign to a single family, tends to confirm the hypothesis. It seems a reasonable, though hardly a conclusive argument.

The San (people like the present Bushmen of the Kalahari) are, along with Pygmies and some other groups that have disappeared, perhaps the most primitive human ethnic groups, and Wade is hardly the first to suggest that they are closer to the human aboriginal population than any other group. Anthropologists have, however, pointed out that even conservative human groups are not entirely static, and it is possible that the San have degenerated.

Wade discusses Donald Brown’s concept of Universal People, an analogy with Chomsky’s (always Chomsky) Universal Grammar. This is really just a different way of talking about quasi-universal characteristics of human society, a subject pioneered in modern times by George Murdoch. In other words, the mother-child bond, male dominance, reciprocity and barter, belief in the supernatural and the practice of some kind of religion. There is a long line of studies, including my own The Politics of Human Nature, and Wade does not seem to realize that the recent works he is citing are hardly path-breaking. One older piece of information is that observation that the San typically work 40 hours a week or less to provide for necessities, make tools, etc.

He quite properly dismisses Elizabeth Marshall Thomas’s characterization of the !kung san as “harmless,” but he readily accepts the other erroneous term, egalitarian. While it is true that there is not much status to be had in a nomadic group of hunter-gatherers, men still dominate over women, adults over the immature, and parents over children. Since there is no need, at their primitive level of existence, for organized social structures, and since any family is free to wander off whenever it feels like it–fission being the normal way of resolving tensions–the !kung have nothing in the way of hierarchy. But, in a society based on the family, the father possesses considerable authority. In other words, one might just as well say that the !kung represent in embryonic form the patriarchal authority that develops into kingship and the state, just as they also represent most social institutions in embryonic form.

Chapter V: Exodus

Roughly 50,000 years ago, so his story goes, a small group of humans left Africa, perhaps in one wave, and made their way to India and eventually, as they split up, to Australia and Europe. They were not the first hominids to leave Africa, and they encounter opposition, particularly from the stocky, barrel-chested Neanderthals who live in Europe. Neanderthals had a large enough brain, but their behavior was not much advanced from their ape-like ancestors. Boys being boys, the groups may have interbred, but the Neanderthals’ mitochondrial DNA, if it has been properly recovered and interpreted, is quite different from the modern humans’. The assumption is–and it can be no more than that–the superior toolkit, weaponry, and organization of the moderns wiped out their primitive competitors.

When a species spreads around the globe, the groups at extreme distances from each other develop distinctive traits. The classic case is the coloration of the herring gull, which goes from white to gray to black. The human extremes are perhaps the Australian aboriginals (and their New Guinea cousins) and European man. The aboriginals’ culture was still paleolithic when Europeans arrived some 45,000 years later, while in Europe, cave paintings show a remarkable artistic sense very early on. Wade accepts the genetic explanation that an allele of the microcephalin gene developed about 37,000 years ago. This allele occurs in about 70% of individuals in Europe and East Asia, but it is rare (25%) in Africa. There are other genes associated with cultural development and intelligence, and Wade seems to be suggesting here–though he admits he is playing with fire–that the differences between, say, the Bushmen of the Kalahari and the ancient Sumerians is rooted in a genetically based difference of intelligence.

Chapter VI: Stasis

Wade wonders why it took 35,000 years, from the time he defeated the Neanderthals, for man to settle down and form permanent settlements. The scene is Europe, the best studied habitat of paleolithic man. Archaeologists define a series of periods.

The Aurignacian, from 45,000 to 28,000 years ago, was a period of pugnacious weapon-users who also decorated the Chauvet cave in France.

The Gravettian, from 28,000 to 21,000, is defined by a new set of stone tools, the invention of the bow, and by crude female figurines with overdeveloped breasts and buttocks suggestive of a fertility cult.
The Solutrean, 21,00 to 16,500 years ago, came after the “Last Glacial Maximum,” which must have made global warming a welcome change. Some long thin tools, it is suggested, might have been made for ceremonial purposes.

The Magdalenian, 18,000-11,00 years ago, developed a lighter toolkit and continued to paint caves.

Obviously some of these cultures overlap in different parts of Europe, and archaeologists, on the basis of a few shards, weapon fragment, and paintings, have not explained the transition from one to another. Wade cites geneticists, however, who have looked at the distribution of sublineages of mitochondrial DNA. Comparing clusters found in Europe and the Middle East, they found that 11 clusters containing 40 lineages account for three fourths of the present European population. They could deduce, they believe, that 87% of Europeans are descended from ancestors “who arrived before the end of the Pleistocene ice age.” The other 13%, it is believed, represent the later arrivals who brought a higher culture with them and led the move to the Neolithic Age. Since Basques have a higher percentage of older clusters, their region is assumed to have been the source of recolonization as the glaciers retreated. Thus, in this account, most modern Europeans are descended from palaeolithic inhabitants and not from the later Middle Eastern immigrants, as had been previously believed. This also implies that the ascent of Europeans to Neolithic culture was not the direct result of a genetic/ethnic shift but of cultural transmission.

As a sidelight, he takes up the taming of the wolf-dog, which may have taken place about 15,000 years ago in Siberia, about the time man was settling down and would have found these rare night-barking wolves useful. A lot of work on this has been done in recent years and it has made the popular media in the past few months. Some small percentage of wolves is able to get along with man and must have, more or less, domesticated themselves. These same creatures, domesticated dogs and tamable wolves, can apparently read human intentions better even than chimpanzees.

People from roughly Siberia also colonized the Americas, but I do not know what to make of the tissue of arguments to prove either the date or the waves (1) in which they came. I simply do not think that anything like proof can be established with such slippery variables.  I am also less than enthusiastic about the attempts to trace the development of Mongoloid and Caucasoid races, in this chapter and elsewhere, on the basis of skin-pigmentation adaption to sunlight, absorbtion of Vitamin D and Folic acid.  If the nature of modern science is bound up with testing hypotheses, I’d like to see, for example, some evidence that people with black skin have high rates of birth defects, miscarriage, etc., when they move to Scandinavia or Canada.  Perhaps I am missing something.

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