Periodic Reporting for period 3 - COMMIOS (Communities and Connectivities: Iron Age Britons and their Continental Neighbours)
Reporting period: 2022-10-01 to 2024-03-31
Recent breakthroughs in ancient DNA and isotope analysis are transforming our understanding of diversity, mobility and social dynamics in the human past. COMMIOS integrates these cutting-edge methods on a scale not previously attempted, to provide a radically new vision of Iron Age communities in Britain (800 BC – AD 100) within their wider European context. At the broad scale, we will conduct the first concerted programme of genome-wide ancient DNA analysis on Iron Age populations anywhere in the world. Along with isotope analysis, underpinned by both osteoarchaeological and cultural archaeological approaches, this will enable us to address issues of population movement and inter-regional connectivity. We will use these new scientific methods to examine the structure and social dynamics of Iron Age societies, including household and kin-group composition, the identification of familial relationships, gender-specific mobility, and the development of social inequalities.
Why is it important for society?
COMMIOS represents a collaboration between archaeologists, geneticists and the wider heritage sector represented by museums and commercial archaeological organisations. As such, it forms a powerful vector for the dissemination of knowledge and understanding of cutting-edge scientific approaches to the human past. Our work on long-term population history gives new insights into the complex inter-relationships between past communities in Europe, prompting fresh perspectives on national identities and new understandings of the fluidity, diversity and mobility of European populations.
What are the overall objectives?
1: To establish the patterning of genetic diversity across Iron Age Britain and to examine the extent to which this corresponds with (a) traditional cultural boundaries, identified through settlement patterns, material culture and linguistic evidence, and (b) genetic clusters identified from analyses of modern DNA.
2: To examine the degree of mobility and connectivity within Iron Age communities in Britain through a suite of isotopic analyses.
3: To characterise the composition of Iron Age cemetery populations in Britain (as a proxy for living communities) in relation to age, sex, diet, health, disability and social inequality.
4: To identify familial relationships within Iron Age funerary contexts in Britain and the degree to which Iron Age communities practiced matrilocal or patrilocal marriage patterns.
Why is it important for society?
COMMIOS represents a collaboration between archaeologists, geneticists and the wider heritage sector represented by museums and commercial archaeological organisations. As such, it forms a powerful vector for the dissemination of knowledge and understanding of cutting-edge scientific approaches to the human past. Our work on long-term population history gives new insights into the complex inter-relationships between past communities in Europe, prompting fresh perspectives on national identities and new understandings of the fluidity, diversity and mobility of European populations.
What are the overall objectives?
1: To establish the patterning of genetic diversity across Iron Age Britain and to examine the extent to which this corresponds with (a) traditional cultural boundaries, identified through settlement patterns, material culture and linguistic evidence, and (b) genetic clusters identified from analyses of modern DNA.
2: To examine the degree of mobility and connectivity within Iron Age communities in Britain through a suite of isotopic analyses.
3: To characterise the composition of Iron Age cemetery populations in Britain (as a proxy for living communities) in relation to age, sex, diet, health, disability and social inequality.
4: To identify familial relationships within Iron Age funerary contexts in Britain and the degree to which Iron Age communities practiced matrilocal or patrilocal marriage patterns.
During the period of the mid-term scientific report (months 1-30), the project team has:
- Obtained samples of prehistoric human remains for aDNA, isotope and osteoarchaeological analysis and AMS dating from institutions and heritage organisations across Britain.
- Implemented integrated sampling protocols for aDNA and isotope sampling of human remains.
- Conducted aDNA analysis on 685 prehistoric individuals from archaeological sites in Britain.
- Obtained aDNA and isotope samples from 50 individuals from the major French Iron Age site of Urville-Naquevllle (Normandy).
- Collaborated with overseas partners to analyse aDNA from 390 prehistoric individuals from archaeological sites in Continental Europe.
- Conducted isotope analyses (including carbon, nitrogen, strontium, oxygen, sulphur and lead) on 74 individuals, as well as 28 animal baseline samples.
- Obtained 96 AMS radiocarbon dates on prehistoric human remains from archaeological sites in Britain.
- Presented 23 conference and seminar papers to a range of academic and non-academic audiences.
- Held an international conference session on ‘Understanding Prehistoric Demography’ at the European Association of Archaeologists Annual Conference, August 2021, including contributors from the UK, Netherlands, Romania, Norway, Spain, France, Austria, Denmark, Slovenia, Belgium, Czechia and USA.
- Disseminated our work to a non-specialist UK audience through an eight-page feature in the popular magazine British Archaeology.
- Disseminated our work to the French archaeological community through a paper in Bulletin de l’Association française pour l’étude de l’âge du Fer.
- Published paper on ‘Large-scale migration into Britain during the Middle to Late Bronze Age’ in the journal Nature.
- Obtained samples of prehistoric human remains for aDNA, isotope and osteoarchaeological analysis and AMS dating from institutions and heritage organisations across Britain.
- Implemented integrated sampling protocols for aDNA and isotope sampling of human remains.
- Conducted aDNA analysis on 685 prehistoric individuals from archaeological sites in Britain.
- Obtained aDNA and isotope samples from 50 individuals from the major French Iron Age site of Urville-Naquevllle (Normandy).
- Collaborated with overseas partners to analyse aDNA from 390 prehistoric individuals from archaeological sites in Continental Europe.
- Conducted isotope analyses (including carbon, nitrogen, strontium, oxygen, sulphur and lead) on 74 individuals, as well as 28 animal baseline samples.
- Obtained 96 AMS radiocarbon dates on prehistoric human remains from archaeological sites in Britain.
- Presented 23 conference and seminar papers to a range of academic and non-academic audiences.
- Held an international conference session on ‘Understanding Prehistoric Demography’ at the European Association of Archaeologists Annual Conference, August 2021, including contributors from the UK, Netherlands, Romania, Norway, Spain, France, Austria, Denmark, Slovenia, Belgium, Czechia and USA.
- Disseminated our work to a non-specialist UK audience through an eight-page feature in the popular magazine British Archaeology.
- Disseminated our work to the French archaeological community through a paper in Bulletin de l’Association française pour l’étude de l’âge du Fer.
- Published paper on ‘Large-scale migration into Britain during the Middle to Late Bronze Age’ in the journal Nature.
Our aDNA analysis has already led to the discovery of a major period of population movement into southern Britain during the Middle-Late Bronze Age (representing approximately 50% genetic turnover within the population of that region), followed by a period of genetic stability during the Iron Age. This marks a highly significant discovery in the field of British prehistory and a major advancement in the study of British population history. One of the most significant findings of our work so far is that a rise in lactase persistence (the ability of adults to digest milk) started around 1,000 years earlier in Britain than it did in Continental Europe. This ability must have conferred some evolutionary advantage, and thus suggests either, (i) a greater reliance on dairy products in Britain during the Bronze and Iron Ages than was the case across the Channel, or (ii) cultural differences in the ways in which dairy products were processed. This rise in lactase persistence began during the Early Bronze Age and was thus independent of the population movements also revealed by our aDNA research. This discovery opens an entirely new avenue of research into the nature of the subsistence economy of later prehistoric Britain, and gives new insights into natural selection for complex genetic traits in later prehistory. We anticipate further progress beyond the state of the art as the project moves forward, especially in relation to kinship and family structure within Iron Age populations, and in the delineation of genetic structure within Iron Age Britain.