Case Study: Unusual Medieval Burials from Tarbat: the evidence from aDNA

Cecily Spall

The Tarbat Discovery Programme is best known for the excavation of an 8th-century Pictish monastic settlement which lay around and beneath the Church of St Colman, Tarbat (Portmahomack), Easter Ross, (MHG8475). The results of the 20-year research programme also identified exceptional archaeology belong to a later medieval settlement of the 13th to 16th centuries. Evidence for housing and craft-working was excavated, as well as over 80 medieval burials from the nave (Carver et al 2016). Following the publication of the monograph, the research programme focussed on further work on the Medieval phases of activity. As part of that initiative a recent scientific enquiry was undertaken into a group of highly unusual burials, including a grave that contained six skulls.

Figure 1: Six-headed burial. ©FAS Heritage/University of York

This grave, positioned in the central part of the nave of the church, was dug to receive an oak coffin containing the body of an adult male, bearing signs of perimortem sharp force injuries. The man was buried with a group of four skulls around his head. Sometime later, the grave was reopened for the burial of a second man, an event accompanied by the rearrangement of the skull of the grave’s earlier occupant. Close by a further grave was dug to the north and contained the body of a younger man and beyond him the body of a man buried clothed wearing woollen leg hose and leather ankle boots. As a group these burials dominate the head of the nave and congregate close to the entrance to the crypt.

Figure 2: Leather boots and hose under block lifted excavation © FAS Heritage/University of York

These highly unusual burials have been the subject of a multi-proxy approach, combining detailed osteological study, radiocarbon dating including Bayesian analysis, multi-isotope analysis, facial reconstruction and ancient DNA analysis. Dating places the skulls and bodies within the six-headed grave and the adjacent burial to the late 13th to early 15th century.

Ancient DNA analysis was undertaken at the Reich Laboratory, Harvard University and targeted nine samples from the four skulls and five burials, of which eight yielded genome-wide data. Results highlight that seven of the individuals are males, with one female identified largely confirming osteological identification with the exception of two of the four extra skulls which identified a skull recorded as female as male and vice versa. The results also show a high diversity of mitochondrial DNA and a relatively low diversity of the Y chromosome which may reflect patrilineal practices, although the data group is too small to confirm this (Dr Claire-Elise Fischer pers comm).

Kinship analysis performed on the six-headed burials indicates a family group composed of five individuals, including a woman. The first and second occupants were probably first cousins once-removed, but other family tree combinations are possible. The four skulls were identified as the paternal grandfather and parents of the second occupant. The grave to the immediate north was that of his son. The fourth skull dated to the 8th to 10th century and was probably a male member of the Pictish monastic community. The selection of this skull is likely to have been intentional and may have been considered a holy relic.

This broad date bracket for this unusual group of burials coincides with a period of political, social and environmental upheaval (Oram 2014c); factors which are inextricably linked. The rise of militarised kindreds, the impact of famine, murraine, plague and growing competition for fertile land are all likely to have influenced the behaviours and social stress manifest in these unorthodox burials. The unusual curation of ancestral skulls may have its origins in prehistoric practice and further research is required. The potential for better understanding medieval funerary behaviour in church and churchyard burials through kinship analysis has clear potential for the Highlands as well as ancient pathogen analysis. The results of the multi-proxy analysis are being prepared for publication and further research is also planned (Spall et al forthcoming).

Further information

Carver, Martin, Garner-Lahire, Justin, and Spall, Cecily 2016 Portmahomack on Tarbat Ness. Changing ideologies in north-east Scotland, sixth to sixteenth century AD, Society of Antiquaries of Scotland: Edinburgh.

Spall, C A, Carver, M, Reich, D, Curtis-Summers, S, Hamilton, D, Olalade, I and Fischer, C forthcoming ‘Skullduggery at Portmahomack, symbolic interment of eight interrelated individuals from the clan period in North-East Scotland’.