A multi-isotope investigation of diet and subsistence amongst island and mainland populations from early medieval western Britain

Objectives: This is the first investigation of dietary practices amongst multiple early medieval populations (AD 500–1000) from Wales and the Isle of Man using carbon, nitrogen, and sulphur isotope analysis. The analysis will illuminate similarities or differences between the diets and subsistence strategies of populations occupying different geographical regions, specifically those living in marginal coastal regions in comparison to inland populations well-connected to ecclesiastical centres and high-status settlements. Materials and Methods: One hundred and two human skeletons were sampled for carbon and nitrogen isotope analysis, and 69 human skeletons were sampled for sulphur isotope analysis from nine cemetery sites from western Britain (Isle of Man = 3, southwest Wales = 4, southeast Wales = 2). Thirteen faunal skeletons from St Patrick's Chapel (southwest Wales) were sampled for carbon, nitrogen, and sulphur isotope analysis. Results: Human δ13C values range from −19.4‰ to −21.2‰ (δ13C mean=−20.4 ±0.4‰, 1σ, n = 86), and δ15N values range from 9.1‰ to 13.8‰ (δ15N mean = 10.8 ± 0.9‰, 1σ, n = 86). δ34S values range from 1.2‰ to 18.4‰ (δ34S mean = 11.6 ± 4.5‰, 1σ, n = 66). Significant differences were noted between the mean δ13C, δ15N and δ34S values according to geographic region: Isle of Man (δ13C = −20.7 ± 0.4‰, δ15N = 11.4 ±0.6‰, n = 13/86; δ34S mean = 17.1 ±0.6, n = 4/66), southwest Wales (δ13C = −20.5 ± 0.4‰, δ15N = 11.0 ±1‰, n = 32/86; δ34S = 16.1 ± 2.1, n = 21/66), and southeast Wales (δ13C =−20.3 ±0.4‰, δ15N = 10.4 ±0.7‰, n = 41/86; δ34S= 8.8 ±3‰, n = 41/66). Faunal δ13C values range from −23.1‰ to −21.2‰ (δ13C mean= −22.1 ±0.5‰, 1σ, n = 13), and δ15N values range from 6.3‰ to 9.8‰ (δ15N mean = 7.3 ± 1.1‰, 1σ, n = 13). δ34S values range from 4.7‰ to 18.4‰ (δ34S mean= 16.3 ± 3.6‰, 1σ, n = 13). Conclusions: The data reveal a reliance on terrestrial protein, however differences are observed between the resource consumption of populations from southwest Wales and the Isle of Man in comparison to the populations from southeast Wales. Populations from the west coast have a marine sulphur signature that reflects their coastal proximity and may also include a reliance on seaweed as a fertiliser/food source. Populations in the southeast were connected to ecclesiastical centres and high-status settlements and had access to inland-grown produce. The data add support to the suggestion that δ34S can be used as a mobility indicator

Evidence of early medieval trade and migration between Wales and the Mediterranean Sea region

Imported Mediterranean pottery recovered from 5th-7th century settlement sites along the south Wales coast indicates that trade and contact between Wales and Byzantium continued following the collapse of the Roman Empire in the early-5th century. It is hypothesised that people as well as pottery continued to travel to Wales from Byzantium, some of whom subsequently settled amongst the local communities. Strontium and oxygen isotope analysis was undertaken on human remains (n=33 individuals) from four early medieval cemeteries from south Wales. The study identified individuals who may not have been local to the British Isles, thus demonstrating that the isotopic analysis of human remains from Wales can further our understanding of migration to Britain during the early medieval period

No man is an island: evidence of pre-Viking Age migration to the Isle of Man

The Isle of Man occupies a central position in the Irish Sea, in close proximity to the coasts of Ireland, north Wales, northwest England and southwest Scotland. The island's location means it presents an ideal stopping point for seafarers navigating the Irish Sea ‘trade highway’, and consequently, during the early medieval period, the island was the focus of power struggles between British and Irish elites, and eventually became the target of attack and subsequent settlement of people from Scandinavia during the Viking Age. It is the Viking-Age evidence that has been central to the discussion of migration to the Isle of Man to date, whilst less consideration has been given to population mobility to the island prior to the 10th century. This paper seeks to address this by presenting strontium and oxygen isotope data for a sample (n = 12) of two pre-10th century cemetery populations from the Isle of Man: Balladoole and Peel Castle. This study highlights evidence for mobility to the island prior to the advent of Viking-Age migrations, and consideration is given to the possible motivations for this early medieval mobility

Biogeochemical tags in fish: predicting spatial variations in strontium and manganese in Salmo trutta scales using stream water geochemistry

Fish scales of Salmo trutta exhibited regional patterning in Sr and Mn concentrations in major third-order tributaries in a small upland catchment (the Dee catchment in Wales, United Kingdom; drainage area �1800 km2) that appeared to reflect regional variability in catchment geology and stream water chemistry. When baseline signatures in scale element concentrations were established at a number of sites (n = 12) among the upper, middle, and lower regions of the Dee catchment, 73% of fish were classified to their region of capture based on Sr and Mn in scales. However, the regional patterning in scale chemistry was degraded when high-resolution catchment-wide variability in scale element concentrations was predicted using element concentrations in stream water as a proxy for Sr and Mn in scales at 792 sites in first-, second-, and third-order tributaries in the catchment (mean distance between neighbouring sites = 738 m, range = 41�3634 m). This analysis indicated that many locations throughout the catchment could be potential source locations and demonstrates that the initial classification accuracy was artificially inflated. We have illustrated limitations of the site-based study design commonly employed in biogeochemical tagging studies. Future studies should take account of potential variation in baseline signatures at fine geographical scales when determining the accuracy of stock discrimination using biogeochemical tags

Modern macaque dietary heterogeneity assessed using stable isotope analysis of hair and bone.

Dietary variability might have been a major factor in the dispersal and subsequent persistence of the genus Macaca in both tropical and temperate areas. Macaques are found from northern Africa to Japan, yet there have been few systematic attempts to compare diets between different modern populations. Here we have taken a direct approach and sampled museum-curated tissues (hair and bone) of Macaca mulatta (rhesus macaques) for carbon and nitrogen stable isotope dietary analyses. Samples from India, Vietnam, and Burma (Myanmar) were taken, representing both tropical and temperate populations. The δ13C values obtained from hair show that the temperate macaques, particularly those from Uttar Pradesh, have a δ13C signature that indicates at least some use of C4 resources, while the tropical individuals have a C3-based diet. However, δ13C values from bone bioapatite indicate a C3-based diet for all specimens and they do not show the C4 usage seen in the hair of some animals, possibly because bone represents a much longer turnover period than that of hair. The results of δ15N analyses grouped animals by geographic region of origin, which may be related to local soil nitrogen values. The greatest variation in δ15N values was seen in the specimens from Burma, which may be partly due to seasonality, as specimens were collected at different times of year. We also investigated the relationship between the hair, bone collagen, and bone bioapatite δ13C results, and found that they are highly correlated, and that one tissue can be used to extrapolate results for another. However, our results also suggest that hair may pick up discrete feeding traces (such as seasonal usage), which are lost when only bone collagen and bioapatite are examined. This has important implications for dietary reconstructions of archaeological and paleontological populations

Elemental composition of aquaculture fish from West Bengal, India: nutrition versus food safety

Aquaculture production continues to grow in West Bengal, where on average people consume 8.2 kg capita−1 of fish each year, and an extensive mosaic of aquaculture ponds has developed along the River Hugli as clay pits are repurposed. The adjacent brickworks and industry (especially tanneries) are a source of environmental pollution, with potential for bioaccumulation of potentially harmful elements (PHEs) in fish farmed in these ponds. Fish from aquaculture present an opportunity to meet food sufficiency in West Bengal; however, an investigation to assess their effectiveness for micronutrient supply balanced against food safety is required. Five ponds close to industrial brick manufacture (urban) and three from rural areas were assessed for the degree of pollution within their pond sediments and waters. Fish were also sampled from each location including a subset from the market in Kolkata to determine the concentrations of PHEs in their fish muscle tissue. Dietary intake and PHE loading were calculated for four fish species to evaluate their nutrient content with respect to recommended daily intakes for adults, e.g. calcium (Ca), potassium (K), magnesium (Mg), iron (Fe), zinc (Zn) and selenium (Se), and to establish whether the provisional maximum tolerable intakes (PMTIs) are exceeded for PHEs, e.g. aluminium (Al), arsenic (As), mercury (Hg), chromium (Cr), tin (Sn), copper (Cu) and lead (Pb). Preliminary results suggest that aquaculture is making an important contribution to nutrition, with fish being a good source of Se. However, in contrast to small wild-caught fish, aquaculture fish in the present study were poor sources of Fe, Ca and Zn. The fish also made substantial contributions (> 10%) to the PMTI of Hg and As. Therefore, there is an urgent need for ongoing monitoring and an expanded sampling programme, as well as research into approaches which might improve the nutritional quality of the farmed fish

Inflammasome-independent role for NLRP3 in controlling innate antihelminth immunity and tissue repair in the lung

Alternatively activated macrophages are essential effector cells during type 2 immunity and tissue repair following helminth infections. We previously showed that Ym1, an alternative activation marker, can drive innate IL-1R-dependent neutrophil recruitment during infection with the lung-migrating nematode, Nippostrongylus brasiliensis, suggesting a potential role for the inflammasome in the IL-1-mediated innate response to infection. Although inflammasome proteins such as NLRP3 have important proinflammatory functions in macrophages, their role during type 2 responses and repair are less defined. We therefore infected Nlrp3-/- mice with N. brasiliensis Unexpectedly, compared with wild-type (WT) mice, infected Nlrp3 -/- mice had increased neutrophilia and eosinophilia, correlating with enhanced worm killing but at the expense of increased tissue damage and delayed lung repair. Transcriptional profiling showed that infected Nlrp3 -/- mice exhibited elevated type 2 gene expression compared with WT mice. Notably, inflammasome activation was not evident early postinfection with N. brasiliensis, and in contrast to Nlrp3 -/- mice, antihelminth responses were unaffected in caspase-1/11-deficient or WT mice treated with the NLRP3-specific inhibitor MCC950. Together these data suggest that NLRP3 has a role in constraining lung neutrophilia, helminth killing, and type 2 immune responses in an inflammasome-independent manner.Alistair L. Chenery, Rafid Alhallaf, Zainab Agha, Jesuthas Ajendra, James E. Parkinson, Martha M. Cooper, Brian H.K. Chan, Ramon M. Eichenberger, Lindsay A. Dent, Avril A.B. Robertson, Andreas Kupz, David Brough, Alex Loukas, Tara E. Sutherland, Judith E. Allen, and Paul R. Giacomi