‘Rid grasse of bones’: A taphonomic study of the bones from midden deposits at the Neolithic and Bronze age site of Runnymede,Surrey, England

Runnymede has large samples of Neolithic and Late Bronze Age animal bones, with contrasting preservation conditions in both periods. The bone evidence has been used to interpret the formation of the site deposits. There are few articulated bones, and no joins were found in butchered bone, indicating that the area studied did not contain primary refuse. Various aspects of bone alteration have been analysed: (i) the proportion of bones with very good surface preservation was high in the in situ Neolithic excavation units and the basal Bronze Age midden, but bones in the upper units were mostly eroded. These units are reworked flood deposits. The greater degree of fragmentation of the bone in the reworked units has been quantified, using a system of recording the ‘zones’ present on each bone, which allows calculation of the fraction present. It is also demonstrated that the reworked units contain a lower proportion of identified bones and a higher proportion of teeth and iaws than the units with well-preserved bone, (ii) Quantification of canid gnawing shows, unexpectedly, that more was recorded on well-preserved bone. Thus recognition of gnawing depends on bone condition. This also confirms that most of the erosion of the bone surface is a post-depositional phenomenon. The sequence of activities is therefore interpreted as follows: meat was cooked and consumed, and the bones discarded for the dogs. At a later stage, larger bones were picked up and thrown away in the river or midden. Some ethnographic examples of periodic cleaning of farming settlements are cited.     

Molecular and morphological analyses of avian eggshell excavated from a late thirteenth century earth oven

Using ancient DNA (aDNA) extracted from eggshell of the extinct moa (Aves: Dinornithiformes) we determined the species composition and number of eggs found in a late thirteenth century earth oven feature at Wairau Bar (South Island, New Zealand) – one of New Zealand’s most significant archaeological sites. Mitochondrial and nuclear DNA signatures confirmed this oven feature contained fragments of at least 31 moa eggs, representing three moa genera: Emeus; Euryapteryx; Dinornis. We demonstrate through the genetic identification of 127 moa eggshell fragments that thickness is an unreliable character for species assignment. We also present a protocol for assessing the preservation likelihood of DNA in burnt eggshell. This is useful because eggshell fragments found in archaeological contexts have often been thermally modified, and heat significantly increases DNA fragmentation. Eggshell is widely used in radiocarbon dating and stable isotope research, this study showcases how aDNA can also add to our knowledge of eggshell in both archaeological and palaeoecological contexts.     

Palynological study of a Mi'kmaw shell midden,Northeast Nova Scotia,Canada

Before now, no palynological studies were made on shell midden deposits in Nova Scotia, despite a long history of archaeological research. A test study of samples taken from the shell midden at Maligomish (Indian Island) on the Northumberland Strait was conducted to determine if sufficient pollen, fern and moss spores, and other non-pollen palynomorphs (NPP's, including fungal remains, algal spores) could be recovered to allow interpretation of environmental conditions at the time of deposition. Several pollen processing methods were tested: sieving and swirling, chemical treatment with cold HCl, 5% KOH and brief exposure to 5% NH₄OH, and treatment with acetolysis solution. We recovered variable amounts of pollen, spores and NPP's from samples taken at 3–5 cm, 5–15 cm and 15–25 cm below surface. Abundant microcharcoal fragments prevented effective use of the swirling technique, but sufficient palynomorphs were recovered by chemical treatments to allow assessment of down-section changes in assemblages. Three radiocarbon ages from Mya arenaria and Crassostrea sp., and measurements of sediment grain size, moisture, organic and inorganic carbon, provide a framework for analysing palynological assemblage changes and context for interpreting differential palynomorph preservation. Despite some oxidation and microbial degradation of palynomorphs in the time interval (ca. 380–1600 cal yr BP), the midden assemblages correlate with pollen zones from marine and lake core sites within ca. 50 km of Maligomish. Shifts in abundances of algal spores, testate amoebae and aquatic plant pollen also indicate changes in depositional conditions during the time of midden use. The study provides the first reference for archaeologists attempting to use palynology for analysis of samples from Nova Scotian shell-bearing contexts.     

Biomolecular and micromorphological analysis of suspected faecal deposits at Neolithic Çatalhöyük,Turkey

Suspected coprolites from midden, burial and room fill contexts at Çatalhöyük were analysed by GC/MS and thin section micromorphology. Assessment of sterol biomarkers enabled a distinction between faecal and non-faecal sources for the deposits to be made, with bile acid biomarkers indicating that many of the faecal deposits are human coprolites. The relative lack of ruminant faeces could be due to this material being used as a fuel source. Deposits in burials were observed to contain soil and plant derived sterols rather than their faecal counterparts. Further analysis in thin section enabled identification of associated materials and contents. Diagnostic inclusions such as bone and plant fragments were only present in some of the human coprolites, which were observed to have a very similar morphology to decayed plant remains. This study illustrates the difficulties in distinguishing coprolites in the field and under the microscope, and demonstrates the importance of integrating biogeochemical methods, particularly when such deposits are used as the basis for interpreting human health and diet, and use-of-space in settlements.     

Determining the habitats of mollusk collection at the Sapelo Island shell ring complex, Georgia, USA using oxygen isotope sclerochronology

Sequential oxygen isotope analysis was performed on Mercenaria spp. (n = 41) and Crassostrea virginica (n = 17) valves excavated from the Sapelo Island Shell Ring complex, coastal Georgia, USA. The data were analyzed to determine the habitats in which the mollusks were harvested in order to gain insight into the subsistence practices of the site occupants. The rationale for this study is based on the observation that temperatures are similar in all of the habitats surrounding the island, but the δ¹⁸O_water trends across the habitats co-vary with salinity. Accordingly, the shells grown in these habitats contain sinusoidal oscillations in δ¹⁸O through ontogeny due primarily to seasonal temperature variation, but the absolute values reflect the salinity ranges of each habitat. Assuming a relatively constant oxygen isotope/salinity gradient since the time of site occupation, it appears that both of these mollusks were exploited over nearly the full range of their salinity tolerances. While a precise estimate of travel distance during collection cannot be made, these data suggest that mollusks were harvested at distances from the site greater than would be predicted using terrestrial foraging models. In addition to providing insight into past subsistence strategies in this region, this research establishes a new method of assessing catchment area and mobility practices.