Bronze- and Iron-Age Celtic-Speakers: What Don't We Know, What Can't We Know, and What Could We Know? Language, Genetics
Total Page:16
File Type:pdf, Size:1020Kb
The Antiquaries Journal, 92, 2012,pp427–49 r The Society of Antiquaries of London, 2012 doi:10.1017⁄s000358151200011x. First published online 23 August 2012 BRONZE- AND IRON-AGE CELTIC-SPEAKERS: WHAT DON’T WE KNOW, WHAT CAN’T WE KNOW, AND WHAT COULD WE KNOW? LANGUAGE, GENETICS AND ARCHAEOLOGY IN THE TWENTY-FIRST CENTURY Patrick Sims-Williams Patrick Sims-Williams, Department of Welsh, Aberystwyth University, Aberystwyth SY23 2AX, Wales, UK. E-mail: [email protected] In 1998 the author published ‘Genetics, linguistics and prehistory: thinking big and thinking straight’, a critique of late twentieth-century attempts to synthesize the disciplines of genetics, linguistics and archaeology. This paper assesses subsequent progress, using examples from various parts of the world, including Britain, Denmark, Finland, France, Frisia, Germany, Hungary, Ireland, Italy, Micronesia, Portugal, Spain and the Canary Islands. The growing importance of mitochondrial DNA and the Y chromosome, rather than classical population genetics, is emphasized. The author argues that ancient DNA and early linguistic data should be used more. Languages mentioned include Aquitanian, Basque, Celtiberian, Etruscan, Finnish, Hungarian, Iberian, Lepontic, Lusitanian, Pictish, Raetic, ‘Tartessian’, Thracian and the Ladin dialect of the Italian Alps. Aspects of the ancient linguistic geography of Scotland and the Iberian peninsula are discussed, as is the difficulty of deciding the direction of spread of Indo-European and non-Indo-European languages. The potential of ancient place and personal names is illustrated from Celtic. In this article I revisit a topic on which I published a paper, ‘Genetics, linguistics and prehistory: thinking big and thinking straight’, in Antiquity in 1998.1 The Antiquity paper was a critique of what was being hailed as a ‘new synthesis’ of archaeology, population genetics and historical linguistics. By the end of the twentieth century, these three disciplines had each produced vast data sets with some bearing on prehistory. It seemed that they might be combined, especially as two of them, genetics and linguistics, had a superficial similarity. Neither cast much direct light on prehistory; ancient DNA and ancient texts were in short supply and, when available in Eurasia, came from different latitudes, DNA happening to survive better in the colder climates which literacy reached later. Yet genetics and linguistics both worked with ‘family tree’ models by which inter- esting ancient branches and trunks might be inferred from a comparison of the visible ‘leaves’ of modern data. The branches of genetic trees were reconstructed on the basis of genetic mutations in one branch rather than another, while the language trees were best reconstructed on the basis of shared linguistic innovations. Some geneticists and linguists confidently estimated the rates of the relevant mutations, and if they were right we would 1. Sims-Williams 1998a. That paper included some Celtic examples, but on Celtic, see further Sims-Williams 1998b. For an update on the latter, see Rodway 2010. Downloaded from https://www.cambridge.org/core. University of Athens, on 26 Sep 2021 at 11:36:58, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S000358151200011X 428 THE ANTIQUARIES JOURNAL be able to date the prehistoric branchings. Linguists, however, remain sceptical about all types of ‘glottochronology’,2 and mutation rates even in mitochondrial DNA (mtDNA) are still under discussion3 – the Y chromosome is still more problematical.4 Certainly, so far, neither discipline has attained anything so precise as radiocarbon dating.5 If linguistic and genetic nodes are not securely fixed in time, neither are they easily fixed in space. At one time linguists used to argue that the original locus of a mother language could be deduced from the location of its daughter languages, but this was shown to be fallacious.6 A similar sort of problem arises in genetics: while the ancestor or ancestress of a particular patrilinear (Y chromosome) or matrilinear (mtDNA) lineage might be located at the epicentre of his or her most diverse surviving descendants, nevertheless (to quote Bryan Sykes) ‘the mother of a clan which is twenty thousand years old cannot have lived in the north of Scotland, even if that might be where the clan is most varied today, for the very practical reason that Scotland was covered in ice at the time’.7 Here is a question that can be tested: how often does the modern genetic data, unaided, point to environmentally and archaeologically credible epicentres? We all know how the fashion swings between assuming population replacement and population continuity. Only under the latter hypothesis does the use of modern data become attractive. What is badly needed is more ancient DNA (aDNA), problematic and expensive though this may be to analyse.8 Even from a thousand years ago, aDNA is worth its weight in gold. For example, analysis of mtDNA from nine skeletons in a Christian cemetery at Kongemarken, in Denmark, has shown that they were not the homogenous little community that might have been expected; in one case the closest modern relatives were mostly in Siberia and India.9 This could be exceptional, owing to the proximity to the port of Roskilde, but more such work is needed before such a result can be explained away. In favourable circumstances, isotope analysis could shed light on exogamy in such communities.10 More interesting still are the mtDNA analyses of prehistoric remains from the Italian Alps. The sole Mesolithic sequence, from Villabruna (c 14,000 BP), has not been observed in any living person, whereas the two Neolithic sequences (c 6,000 BP, from Mezzocorona and Borgo Nuovo), like that of the famous Tyrolean ‘ice man’ (c 5,300 BP), all resembled modern sequences throughout Europe and were at the same time as diverse among the 11 three of them as any three random modern Europeans. From Neolithic sites (c 7,500 BP) from slightly further north, the mtDNA of all twenty-four individuals also resembled that 2. Renfrew et al 2000; Mallory and Adams 2006, 94; Holm 2007; cf Heggarty et al 2010, 3831. 3. Mishmar et al 2003, 176; Ho and Endicott 2008; Henn et al 2009; Soares et al 2009 and 2010; Kondrashov and Kondrashov 2010, 1171; cf Forster et al 1996; Saillard et al 2000. 4. Wilson et al 2001, 5081; cf Xue et al 2009; Busby et al 2012. 5. Gamble et al 2005, 194, 206. Although I sympathize with Mike Richards’s negative remarks about DNA evidence (Richards 2004), the whole field is in its infancy, as he indicates, and it must be remembered that radiocarbon dating too had its infancy. We are all priceless walking libraries of genetic (and linguistic) prehistory; the challenge is how to read the contents. A century of prehistorians misinterpreting biological evidence (Sims-Williams 2004) suggests that many errors are still to be made. 6. Dyen 1956. See Nichols 1997, 130; Sims-Williams 1998a, 510; McMahon 2004, 8. 7. Sykes 2001, 200; cf Bandelt et al 2002, 102. 8. O’Rourke 2007. 9. Rudbeck et al 2005. 10. Cf Bentley et al 2003 and 2008. 11. Di Benedetto et al 2000. Downloaded from https://www.cambridge.org/core. University of Athens, on 26 Sep 2021 at 11:36:58, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S000358151200011X LANGUAGE, GENETICS AND ARCHAEOLOGY IN THE TWENTY-FIRST CENTURY 429 of modern Europeans, according to Haak et al.12 OneMesolithicsampleversustwenty- seven Neolithic ones is not enough to prove a discontinuity between Mesolithic Europe versus Neolithic and modern Europe. Indeed, Haak et al suggestthatsixoftheirtypes have few living parallels because they were swamped by Palaeolithic survivors. But we are at least dealing with solid data here. We just need more of it so as to know whether it is representative or merely anecdotal, a familiar predicament for prehistorians. In August 2008 there was a media frenzy about the successful DNA analysis of forty Bronze Age skeletons of c 3000 BP from the Lichtenstein cave in the Harz Mountains. The media were interested in two local gentlemen who seem to be direct descendants of the cave dwellers; prehistorians may be more interested in contrasting as well as comparing the ancient DNA with that of modern and ancient Europeans. Most recently, analysis of Y-chromosome DNA from Neolithic caves at Treilles near Aveyron (Midi-Pyre´ne´es), France (c 5000 BP), and Avellaner, Cogolls, Catalonia (c 7000 BP), showed more affinities with Neolithic DNA from Germany and the Tyrolean ‘ice man’ than with typical modern European males. The mtDNA, however, resembled typical modern European populations.13 Since I wrote the 1998 paper, geneticists have concentrated less on classical popula- tion genetics, which presented historically ambiguous composite clines, and more on mtDNA and the Y chromosome, which have the advantage of being passed down exclusively through the female and male lines respectively, offering the hope of unique historical explanations,14 possibly involving separate female and male histories (eg indi- genous Mesolithic females marrying incoming Neolithic farmers).15 Clearly there is plenty of relevant genetic data surviving in modern populations. But if you want to use it to get back to a complete view of prehistory, it has a serious limitation. The mathematical reason was shown by the Revd H W Watson in 1875 in his classic paper ‘On the prob- ability of the extinction of families’.16 He dealt in surnames, but the same process applies to Y chromosomes, and mtDNA too.17 By what is now known as a ‘power law’,18 Watson found that if you start with, say, a million surnames, and (say) one man in three has no sons, one has one, and one has two, even within five generations you expect to lose two-thirds of the surnames.