Genetics, Archaeology and the Wider World

Article excerpt

Molecular biology is prompting a renewed interest in genetic histories of ancient peoples. What are the old 'ethnic units' of these modern studies?

In her recent review (1995), Erika Hagelberg referred to Cavalli-Sforza, Menozzi & Piazza's enormous book, The history and geography of human genes (1994), as having the 'feel and authority' of a Bible. There may, unfortunately, be further parallels: the Bible has been the cause of many arguments as well as rather more damaging clashes, most of which derive from differing interpretations as well as disputed authority. Modern academic research into genetics has become part of a revitalized debate by a variety of people about the relevance of evolutionary theory and the relationship of genetic data to behaviour, culture, identity, and race. Although Cavalli-Sforza et al. are clearly at the responsible end of the spectrum of debate, the 'dismay of scholars in less "trendy" subjects than genetics' at the direction of much funding is caused by more than mere jealousy over research money.

While part of the field certainly includes the discussion of DNA evidence in a murder trial, in other contexts Zhirinovsky's supporters in Russia are calling for new research - by anthropologists and geneticists among others - to 'prove' the disadvantages of racial impurity. The interpretation of the mass of genetic material is certainly 'not without its problems', when Robert Sokal, whom Hagelberg mentions approvingly, is also publishing articles such as Genetic relationships of European populations reflect their ethnohistorical affinities (Sokal et al. 1993). Those authors have 'employed a European ethnohistory database, developed in our laboratory' which 'documents the known locations and movements of 891 ethnic units over the past 4,000 years' (1993: 56). The data-base contains records which 'list the name of a "gens" or tribe (or that of an archaeological horizon in the case of prehistorical records)' [my emphasis] (1993: 57).

The genetic researcher has to pretend that some assigned or claimed identity in the present relates to some constant which can be extrapolated back into the distant past. But as Moore (1995: 30) has also pointed out, Cavalli-Sforza et al. (not to mention Sokal and his colleagues) seem unaware of the 'transitory nature of ethnic identity', and happily revive the old culture=people hypothesis. Archaeological assemblages are treated as if defining people in a way archaeology has found unreasonable for decades. Apart from such historical and archaeological naivete, the point is that this genetic data and these interpretations are not being presented in a political vacuum, however much people might wish them to be.

A second problem derives from the lack of time resolution inherent in genetic studies of modern populations. Take this example from the same authors discussing their genetic maps of Europe (Cavalli-Sforza et al. 1993: 642-3):

The expansions of pastoral nomads . . . may well explain the migrations of people speaking Indo-European languages not only to India but also to Europe, as suggested by Gimbutas but rejected by other archaeologists including Renfrew. The synthetic maps based on the third . . . and sixth PCs [Principal Components] of Europe indicate expansions that correspond geographically to two of the three origins of Kurgan expansions suggested by Gimbutas [between 4000 and 2500 BC]. On the other hand, these may be partially confused with the later expansions of, for example, the Scythians and of barbarians who infiltrated or conquered the Roman Empire before and after its fall.

In other words, modern genetic studies are at present unable to distinguish on genetic grounds between possible movements of people and consequent distribution of genes over a period of four millennia. Much of the genetic information can only be used to suggest population processes with genetic consequences in earlier prehistory by assuming coarse and extreme models of 'demic diffusion'. …