Provenancing antiquarian museum collections using multi-isotope analysis.

Many of the most significant archaeological sites in Europe were excavated by antiquarians over one hundred years ago. Modern museum collections therefore frequently contain human remains that were recovered during the nineteenth and early twentieth centuries. Here we apply multi-isotope analysis (87Sr/86Sr, δ 18O, δ 13C, δ 15N) and 14C dating to evaluate the provenance of human remains within a collection that is thought to have been recovered from one of the most important archaeological sites in Britain. Excavated in 1910, the site of Coldrum in Kent is a megalithic burial monument that may be one of the earliest sites associated with the transition to farming in Britain. The interpretation of this site is therefore key to understanding how agriculture began. Using isotope analysis we show that although the human skeletal collections attributed to Coldrum do contain some of the earliest dated Neolithic human remains in Britain, they also contain the remains of individuals of fifth to seventh centuries AD date. We evaluate subsistence and mobility patterns of early Neolithic populations and provide new information about the origins of those individuals in the collection that date to the fifth to seventh centuries AD. We demonstrate the utility of employing isotope analysis to provide direct and independent information about the provenance of human remains in museum collections.

Tracking natural and anthropogenic Pb exposure to its geological source.

Human Pb exposure comes from two sources: (i) natural uptake through ingestion of soils and typified by populations that predate mining activity and (ii) anthropogenic exposure caused by the exposure to Pb derived from ore deposits. Currently, the measured concentration of Pb within a sample is used to discriminate between these two exposure routes, with the upper limit for natural exposure in skeletal studies given as 0.5 or 0.7 mg/kg in enamel and 0.5/0.7 µg/dL in blood. This threshold approach to categorising Pb exposure does not distinguish between the geological origins of the exposure types. However, Pb isotopes potentially provide a more definitive means of discriminating between sources. Whereas Pb from soil displays a crustal average 238U/204Pb (µ) value of c 9.7, Pb from ore displays a much wider range of evolution pathways. These characteristics are transferred into tooth enamel, making it possible to characterize human Pb exposure in terms of the primary source of ingested Pb and to relate mining activity to geotectonic domains. We surmise that this ability to discriminate between silicate and sulphide Pb exposure will lead to a better understanding of the evolution of early human mining activity and development of exposure models through the Anthropocene.

Land use and mobility during the Neolithic in Wales explored using isotope analysis of tooth enamel.

OBJECTIVES: The nature of land use and mobility during the transition to agriculture has often been debated. Here, we use isotope analysis of tooth enamel from human populations buried in two different Neolithic burial monuments, Penywyrlod and Ty Isaf, in south-east Wales, to examine patterns of land use and to evaluate where individuals obtained their childhood diet. MATERIALS AND METHODS: We employ strontium (87 Sr/86 Sr) and oxygen (δ18 O) and carbon (δ13 C) isotope analysis of enamel from adjacent molars. We compare strontium isotope values measured in enamel to locally bioavailable 87 Sr/86 Sr values. We combine discussion of these results with evaluation of new radiocarbon dates obtained from both sites. RESULTS: The majority of enamel samples from Penywyrlod have strontium isotope ratios above 0.7140. In contrast, the majority of those from Ty Isaf have 87 Sr/86 Sr values below 0.7140. At Penywyrlod oxygen isotope ratios range between 25.9 and 28.2 ‰ (mean 26.7 ± 0.6 ‰, 1σ, n = 15) and enamel δ13 Ccarbonate values range between -18.0 and -15.0 ‰ (mean -16.0 ± 0.8 ‰, 1σ, n = 15). At Ty Isaf oxygen isotope ratios exhibited by Neolithic individuals range between 25.4 and 27.7 ‰ (mean 26.7 ± 0.6 ‰, 1σ, n = 15) and enamel δ13 Ccarbonate values range between -16.9 and -14.9 ‰ (mean -16.0 ± 0.6 ‰, 1σ, n = 15). DISCUSSION: The strontium isotope results suggest that the majority of individuals buried at Penywyrlod did not source their childhood diet locally. One individual in this group has strontium isotope ratios that exceed all current known biosphere values within England and Wales. This individual is radiocarbon dated to the first few centuries of the 4th millennium BC, consistent with the period in which agriculture was initiated in Wales: the results therefore provide evidence for migration during the transition to farming in Wales. In contrast, all individuals sampled from Ty Isaf post-date the period in which agriculture is considered to have been initiated and could have sourced their childhood diet from the local region in which they were buried.

Isotopic evidence for residential mobility of farming communities during the transition to agriculture in Britain.

Development of agriculture is often assumed to be accompanied by a decline in residential mobility, and sedentism is frequently proposed to provide the basis for economic intensification, population growth and increasing social complexity. In Britain, however, the nature of the agricultural transition (ca 4000 BC) and its effect on residence patterns has been intensely debated. Some authors attribute the transition to the arrival of populations who practised a system of sedentary intensive mixed farming similar to that of the very earliest agricultural regimes in central Europe, ca 5500 BC, with cultivation of crops in fixed plots and livestock keeping close to permanently occupied farmsteads. Others argue that local hunter-gatherers within Britain adopted selected elements of a farming economy and retained a mobile way of life. We use strontium and oxygen isotope analysis of tooth enamel from an Early Neolithic burial population in Gloucestershire, England, to evaluate the residence patterns of early farmers. Our results are consistent with the hypothesis that early farming communities in Britain were residentially mobile and were not fully sedentary. Results highlight the diverse nature of settlement strategies associated with early farming in Europe and are of wider significance to understanding the effect of the transition to agriculture on residence patterns.