Monthly Archives: April 2020

Human remains from Dunragit

Iraia Arabaolaza is an osteoarchaeologist at GUARD Archaeology Ltd, whose primary research interests are human pathologies and in particular childhood pathologies. Iraia is one of the principal co-authors for the A75 Dunragit Bypass post-excavation works and is this month’s guest contributor to the blog.

I have always believed that the study of human remains provides a direct link to our prehistoric ancestors. As archaeologists we generally rely on features (pits, structures, post-holes) and artefacts to try and reconstruct a history of how people lived in the past. The study of human remains offers an insight into a person’s biological sex, age, possible diseases that they suffered during their lifetime and even in some rare cases the cause of their death. It also provides an opportunity to better understand their belief system and associated burial rituals.

Urn SF61 during excavation

All the human remains recovered and studied from Dunragit were cremated and came from two sites, mainly Boreland Cottage Upper (27 cremations) with further three cremation remains from the Drumflower site. The cremations were either placed in urns (the minority) or in pits as a cremation deposit (the majority). No remains of pyres were encountered in the excavated areas; however, charcoal remains recovered from the cremation deposits indicated that it was mainly oak and alder that were used during the cremation rite. The earliest cremations dated to the Early Bronze Age (approximately 2000 BC) and were cremated using oak charcoal while the Middle Bronze Age cremations (approximately 1500 BC) used alder and other species including oak as fuel for their pyre.

Cremation pit 531 during excavation

The cremated remains were fully calcified, as they were white in colour, which indicates that the bones were subjected to a high temperature between 645 -<940ºC. The surface texture of the bones, cracks and warping suggests that most bodies were not de-fleshed prior to burning, and that the bodies were burnt soon after death. A skull fragment recovered from an urn cremation showed green/blue staining which might indicate that the bone was in contact with a grave good with copper content. However, no grave goods were found within this particular cremation, apart from the urn that contained the remains, which indicates that the metal item was not deposited within the cremation burial.      

Plan of Boreland Cottage Upper cemetery complex

Most of the earlier cremation burials were small in weight and rather fragmented. This together with the lack or under representation of certain skeletal elements (i.e. shoulder, pelvis, rib cavity) suggests that most of the remains were possibly deposited as tokens in pits and were not representing a complete burial. Analysis based on the relative size of the bones indicated that most of the cremation deposits included the remains of at least one adult person. At Boreland Cottage Upper there was a clear change in the burial rite from a more clustered distribution in the earlier Bronze Age to more evenly distributed depositions concentrated around three ring ditches during the Middle Bronze Age. Moreover, multiple collective cremation burials were identified during this period. One urn cremation revealed two adults, one of them aged between 40-44 years and remains of a female while sub-adults or individuals younger than 18 years old were also identified buried together with an adult in three other burials. This is quite common in prehistory and could suggest they were cremated and deposited at the same time.  

Several pathological conditions were noted in some of the human remains recovered from Dunragit. The pathologies included an unidentified healed infection/trauma and small bony growth, osteoarthritis on the spine and a possible sharp trauma/dismembering cut mark. Schmorls nodes, also known as intervertebral disc herniation, was also apparent – this is a lesion that appears in the vertebral body but usually causes no symptoms.  Most of these are relatively easy to diagnose even on small fragments of archaeological bone and are common within the archaeological record.  However, the cause of the possible infection/healed trauma remains unknown as its causes can be varied and are difficult to interpret without assessing the full skeleton.  The possible cut marked bone is slightly more unusual although not unheard of from archaeological assemblages.   The discovery of the cremation cemetery complex at Dunragit is of national significance. The quantity of cremations encountered in Dunragit (30), as well as the extensive use of the site for over 500 years has provided a rare insight into the Bronze Age burial practice in southwest Scotland. Although burial rites during the Bronze Age are characterised by their variety, there was clear distinction between the Early and Middle Bronze Age cremations found across the Dunragit site. While the earlier cremations were token symbolic depositions in pits, some of them with associated grave goods, the latter cremations were by and large the full remains, were associated with the ring ditch structures and were often contained in urns. Variations between these two populations in terms of their use of, and mobility within, the landscape were also apparent from the stable isotopes analysis on the cremations, but that will be another blog, while another forthcoming blog will cover the grave goods associated with these burial rites….

Share this page

Luminescence dating of Iron Age roundhouses at Myrtle Cottage, Dunragit

Alan Cresswell is a Research Associate at the Scottish Universities Environmental Research Centre, University of Glasgow, whose primary research interests are luminescence analysis and dating of sediments in archaeological and geomorphological investigations and wider interests in environmental radioactivity and dosimetry. Alan is one of the specialist authors for the A75 Dunragit Bypass post-excavation works and is this month’s guest contributor to the blog.

Optically Stimulated Luminescence (OSL) is an approach that can precisely date the deposition of sedimentary layers on archaeological sites. It utilises signals that develop in mineral grains in response to exposure to natural sources of ionising radiation from the surrounding sediments and cosmic rays. When radiation interacts with mineral grains, electrons within the mineral are excited into high energy states, some of which are metastable allowing this charge to be trapped. This trapped charge can be released by exposure to light or heat, emitting light, and with suitable equipment these photons can be counted. The number of photons counted can be related to the radiation dose the mineral had received by calibration in the laboratory using known radiation doses. The combination of received dose and the radiation dose rate gives a time since the trapped electrons in the mineral had last been released, which for materials deposited in many settings would correspond to the time that these minerals had been buried.

Investigations by GUARD Archaeology along the route of the A75 bypass at Dunragit included a set of roundhouses within a former dune system at Myrtle Cottage, with accumulated sand layers within and between these structures. As the Iron Age settlement unearthed at Dunragit was situated in an aeolian environment and as some deposits showed a paucity of organic material this method provided an opportunity for dating that would not otherwise be possible. Thirteen samples of sand were collected during the excavations from layers under structures 1 and 2, between the two structures, within the two structures and from the wall cuts. Quartz grains from these sands were analysed using OSL to determine whether the structures were contemporary, or if not, may indicate a sequence of construction for these two nearby structures.

The layers beneath the structures consist of a natural layer dated to 3100 ± 650 BC, consistent with the mid Holocene tidal high stand for this section of the Solway coast, and an occupation layer dated to 1540 ± 290 BC suggesting human activity on the site significantly before the Iron Age. The wall cut for structure 2 is dated to 350 ± 240 AD, and cuts through occupation layers dated to 400-100BC and into the natural materials. Occupation layers outside structure 2 are approximately contemporary with the wall cut, potentially produced from material excavated from this ditch. The wall cut for structure 1 is dated to 400 ± 190 AD but cuts through the layers outside structure 2, suggesting that the construction of structure 1 slightly post-dates the construction of structure 2.

Overall, this dating evidence confirms the material culture that was recovered from the Iron Age settlement, which included an unusual Roman copper alloy brooch, an Iron Age iron penannular brooch and a rare, curved iron leatherworking knife of likely Roman Iron Age date. The Iron Age settlement at Dunragit, now dated to the centuries around the turn of the First Millennia BC/AD, is a welcome addition to a suite of settlements in Galloway that date to this specific period. These include the variety of settlements around Cults Loch, the large enclosed settlement at Rispain Camp and the promontory fort at Carghidown. These settlements provide useful dating, structural and material culture comparisons with the Iron Age settlement at Myrtle Cottage.

Share this page