Ancient DNA suggests that artificial islands were party spots for the elite

New integrated molecular approaches for investigating lake settlements in north-western Europe. Antony G. Brown et al. Antiquity, Sep 28 2022. https://www.cambridge.org/core/journals/antiquity/article/new-integrated-molecular-approaches-for-investigating-lake-settlements-in-northwestern-europe/7A0304934781CF67D37DF76FCC87C54B

Abstract: Lake settlements, particularly crannogs, pose several contradictions—visible yet inaccessible, widespread yet geographically restricted, persistent yet vulnerable. To further our understanding, we have developed the integrated use of palaeolimnological (scanning XRF, pollen, spores, diatoms, chironomids, Cladocera, microcharcoal, biogenic silica, SEM-EDS, stable-isotopes) and biomolecular (faecal stanols, bile acids, sedaDNA) analyses of proximal and through-crannog cores in south-west Scotland and Ireland. Both can be effective methods sets for revealing occupation chronologies and identifying on-crannog activities and practices. Strong results from sedaDNA and lipid biomarker analyses demonstrate probable on-site animal slaughter, food storage and possible feasting, suggesting multi-period, elite site associations, and the storage and protection of valuable resources.

Context and discussion

The scientific techniques outlined here can provide sophisticated insights into the lifeways of societies ranging from the Neolithic to the post-medieval periods (AD 1603–present), even if via the cultural filter of wetland site activities. A key task for future work is to integrate these environmental methods with the more representative evidence generated by excavation of crannog settlements and associated dryland sites, and their wider cultural contexts. Focusing more specifically on crannogs, the frequent identification of ‘high-status’ activities and goods on some of these sites not only supports their role as places for the protective custody of valuable resources, but also suggests a degree of social exclusion combined with the display of power and wealth (O'Sullivan Reference O'Sullivan2004). Although seemingly low-status crannogs have been recorded, such as Sroove in Ireland (Boyle Reference Boyle2004), this impression may be the result of later reuse and disturbance, as the scale of resources required for crannog construction implies considerable investment. Indeed, biomolecular (and geochemical) methods may also be able to identify earlier activities that have left no trace in the on-site material culture, particularly as this could include infrequent events, such as feasting or ceremonial activities.

Shelley (Reference Shelley2009) has shown that for the medieval period in Scotland, crannogs can be regarded as watery lodges or palaces, which later went out of fashion as display became increasingly mediated through estates, mansions and gardens. The royal association of many crannogs suggests that this status display may also have been a factor during earlier periods in both Scotland and Ireland. Similarly, there was ecclesiastical use of some crannogs—especially in the early medieval period (AD 410–1066), following the model of ascetic monasticism whereby a central monastery was surrounded by satellite hermitages in remote locations and, particularly, on islands—although this was far more variable in Ireland (Bitel Reference Bitel, Alison and Bitel2020). An additional element here is the early Christian tradition of islands as places of holiness, retreat and redemption—a practise which can also have practical advantages through a degree of protection and self-sufficiency. Religious associations are visible through artefacts, such as crosses, and the later documented use of crannogs by the Church (Shelley Reference Shelley2009; Stratigos & Noble Reference Stratigos and Nobel2015). All of these considerations imply that the use and importance of crannogs were highly variable in different periods and places. One implication is that there is a fundamental limit to what we can discover about crannogs by studying them in isolation. A key insight comes from their changing use over time, but this relies entirely on increasing the number of dated crannogs, dating their construction and reuse, and comparing these dates to nearby dryland sites (e.g. settlements, raths and ringforts).