Stable isotope analysis of Pacific rat (Rattus exulans) from archaeological sites in Mangareva (French Polynesia): The use of commensal species for understanding human activity and ecosystem change

Stable carbon and nitrogen isotope analysis was applied to archaeological specimens of the commensal Pacific rat (Rattus exulans) to investigate nutrient fluxes in prehistoric socio-ecosystems on Mangareva (Gambier Islands) and their implications for anthropogenic environmental change. The Pacific rat – ubiquitous in Polynesian archaeological sites – is characterised by low dietary selectivity and a limited home range, making it an ideal candidate for assessing changes in island food webs. Temporal trends in diet-derived bone collagen δ¹³C and δ¹⁵N values are assessed from three sites: The Onemea Site, Taravai Island (TAR-6), Nenega-iti Rockshelter, Agakauitai Island (AGA-3) and Kitchen Cave Rockshelter, Kamaka Island (KAM-1). An overall trend of decreasing δ¹⁵N values in rat bone collagen over time reflects archipelago-wide changes to island socio-ecosystems most likely resulting from seabird population declines. Differences in site function and human activity may have also influenced local rat dietary patterns. Stable isotope analysis of the Pacific rat provides a low-impact line of evidence towards the reconstruction of human-centred food webs and the flow of nutrients within island socio-ecosystems.     

Stable Isotope Analysis of Human and Faunal Remains from the Anglo-Saxon Cemetery at Berinsfield,Oxfordshire: Dietary and Social Implications

Stable carbon and nitrogen isotope values were obtained from human and faunal bones from the Early Anglo-Saxon cemetery site at Wally Corner, Berinsfield, Oxfordshire, U.K. These values were used to characterize the diet of the burial community as a whole and to analyse dietary patterns within sub-groups determined by sex, age, grave goods, and possible household arrangement. While dietary variability is observed in all sub-groups tested, we identify an apparent distinction between the average diets of individuals classified as “wealthy” and “intermediately wealthy” and those classified as “poor”. A similar dietary difference indicates a status-based age differential between males under and over 30 years old, also reflected in the archaeological record. A notable absence of dietary differentiation was noted between males and females at Berinsfield, indicating that sex-based societal classification did not significantly influence an individual's access to the various food sources available to the Berinsfield community. Conclusions drawn from these isotopic data are of use in adding to the picture of daily life and social structure in early Anglo-Saxon Britain.     

Domestic dog (Canis familiaris) diets among coastal Late Archaic groups of northeastern North America: A case study for the canine surrogacy approach

The Canine Surrogacy Approach (CSA) is a form of analogy in which stable isotope information from dog remains is used as a proxy for associated human keepers. The approach has garnered increasing attention in recent years due to its capacity to provide information on human diets in contexts where human remains are limited or unavailable. CSA applications have often been conducted on an ad hoc basis and rarely has the human–dog analogy been treated systematically or cohesively. This case study aims to remedy this issue. Using a recently developed CSA interpretive framework (Guiry, 2012), we test the feasibility of using dog bone collagen stable carbon and nitrogen isotope signatures as a proxy for their human keepers among two similar marine oriented Late Archaic populations that occupied the northeastern coast of North America. After characterizing the feasibility of CSA applications in these archaeological contexts, the CSA is then used to reconstruct diet at a culturally related site at which no human remains have been recovered.     

Dogs as Analogs in Stable Isotope-Based Human Paleodietary Reconstructions: A Review and Considerations for Future Use

In contexts where human remains are scarce, poorly preserved, or otherwise unavailable for stable isotope-based paleodietary reconstruction, dog bone collagen as well as other tissues may provide a suitable proxy material for addressing questions relating to human dietary practices. Inferences drawn from applications of this ??canine surrogacy approach?? (CSA) must be made with caution to ensure the accuracy and transparency of conclusions. This paper shows that CSA applications are essentially analogical inferences which can be divided into two groups that provide specific types of information and may require different levels of substantiation. A framework of three categories of factors is outlined to aid in establishing positive, negative, and neutral elements of comparison of dog and human diets. CSA applications may benefit from explicitly detailing the type and nature of the analogical reasoning employed and from providing a systematic assessment of the degree to which stable isotope values of dogs and humans under comparison are thought to be like, unlike, or of unknown likeness.     

The fish of Lake Titicaca: implications for archaeology and changing ecology through stable isotope analysis

Research on past human diets in the southern Lake Titicaca Basin has directed us to investigate the carbon and nitrogen stable isotopes of an important dietary element, fish. By completing a range of analyses on modern and archaeological fish remains, we contribute to two related issues regarding the application of stable isotope analysis of archaeological fish remains and in turn their place within human diet. The first issue is the potential carbon and nitrogen isotope values of prehistoric fish (and how these would impact human dietary isotopic data), and the second is the observed changes in the fish isotopes through time. Out of this work we provide quantitative isotope relationships between fish tissues with and without lipid extraction, and a qualitative analysis of the isotopic relationships between fish tissues, allowing archaeologists to understand these relationships and how these values can be applied in future research. We test a mathematical lipid normalization equation to examine whether future researchers will need to perform lipid extraction procedures for Lake Titicaca fish. We also analyze a number of aquatic plants to better understand the range of isotopic signatures of the Lake Titicaca ecosystem. We use these data to better understand prehistoric human diet and the role that fish may have played in the past as well as potential changes in local lake ecology through time.     

Diet Variability and Stable Isotope Analyses: Looking for Variables Within the Late Neolithic and Iron Age Human Groups from Gougenheim Site and Surrounding Areas (Alsace,France)

Several human groups (from the Neolithic to the Bronze Age) have been analysed in France during the past decade (mainly for C and N stable isotope) as part of research programmes focusing on prehistoric dietary variability. The environment, cultural/social choices or even biological characteristics are among the parameters influencing food acquisition and consumption. This short report presents the first diachronic isotopic results on the palaeodiet in northeastern France. Because of the exceptional archaeological characteristics (human deposits in various positions in pits) of the bone collection from the site of Gougenheim and the surrounding areas (Late Neolithic‐Iron Age, Alsace, France), this assemblage provides a new isotopic dataset to study diet and the potential relationship with social elements or other factors involved in food choices. In order to obtain individual palaeodietary information, carbon and nitrogen stable isotope analyses were performed on 23 adults and 20 immature human bone collagen samples as well as on 25 animal remains. Data were then combined with zooarchaeological and anthropological/archaeological results to reconstruct part of the dietary pattern (i.e. protein consumed) and to detect possible links between the deposit and individual or group social status, defined here by specific mortuary practices. For the Late Neolithic period, isotopic values show, among other things, a wide δ¹³C range within the female human group, which is statistically lower than the male one. Women probably consumed more diversified food sources, suggesting increased residential mobility. Although body deposits point to the presence of two distinct subgroups, no relationship with animal protein intake was identified. Moreover, the comparison with Iron Age individuals brought to light different dietary patterns between the two periods, indicating that stable isotope values were affected throughout time either by increased millet/legume consumption or environmental/anthropic changes. Copyright © 2014 John Wiley & Sons, Ltd.     

What's in a bone? Recent advances in archaeological bone chemistry

This paper focuses on advances in archaeological bone chemistry since 1989. At that time studies generally shifted from development and application of techniques in bone chemistry to more experimental approaches. In stable isotope studies, controlled feeding experiments have been carried out to determine the routing of various dietary components into bone tissues. Biological apatite has been added to collagen as a tissue of study for stable carbon isotope analysis, providing the ability to study much older remains. Other elements have been added such as hydrogen for the study of paleoclimate and oxygen and strontium isotopes to study life history. Trace element studies have focused on methods of detecting and controlling for diagenesis, and barium has been added to the list of useful dietary indicators. Attempts to extract DNA from archaeological bone have been successful, however, this field is still in its early stages in terms of applications to understanding prehistoric biological relationships.     

FOCUS: effect of diet and protein source on carbon stable isotope ratios in collagen: follow up to

We analyzed carbon stable isotope data from bone collagen of animals consuming varied experimental diets, including recently published data from Warinner and Tuross [Warinner, C., Tuross, N., 2009. Alkaline cooking and stable isotope tissue–diet spacing in swine: archaeological implications. Journal of Archaeological Science 36, 1690–1697; this journal]. Comparing regression lines for the relationship between collagen and diet δ¹³C, we show that protein source, and not physiology, explains the apparent taxonomic difference between swine and rodents reported in that paper. Our results reveal a complex relationship between whole diet and dietary protein in determining collagen δ¹³C values, such that in many cases, collagen alone may not provide reliable reconstructions of paleodiet. We advocate the simultaneous use of both collagen and apatite δ¹³C, whenever possible, to assess the diets of prehistoric peoples.     

Sulphur isotope evidence for freshwater fish consumption: a case study from the Danube Gorges,SE Europe

To explore the use of sulphur isotopes as an indicator of the consumption of freshwater fish, we undertook sulphur isotope analysis on bone collagen extracted from humans and animals from five archaeological sites from the Danube Gorges region dating from the Mesolithic to the middle Neolithic periods. The results show a difference in the sulphur isotope values between freshwater and terrestrial ecosystems of 8.7‰. To reconstruct human diets, bone collagen from 24 individuals was analysed for carbon, nitrogen and sulphur isotopic values. The nitrogen isotope ratios ranged from 10.3 to 16.5‰ and the carbon isotope ratios ranged from −20.8 to −18.3‰. Low nitrogen isotope values were found for individuals with low sulphur isotope ratios reflecting the low sulphur isotopic values of the terrestrial animals. The highest human nitrogen isotope values coincided with higher sulphur isotope ratios, which are related to the higher sulphur isotope values of the freshwater fish. Intermediate human sulphur isotopic ratios between these two extremes showed mixed diets of both terrestrial and freshwater resources.     

A Simple(R) Model to Predict the Source of Dietary Carbon in Individual Consumers

Quantitative individual human diet reconstruction using isotopic data and a Bayesian approach typically requires the inclusion of several model parameters, such as individual isotopic data, isotopic and macronutrient composition of food groups, diet‐to‐tissue isotopic offsets and dietary routing. In an archaeological context, sparse data may hamper a widespread application of such models. However, simpler models may be proposed to address specific archaeological questions. As a consequence of the intake of marine foods, individuals from the first century ad Roman site of Herculaneum showed well‐defined bone collagen radiocarbon age offsets from the expected terrestrial value. Taking as reference these radiocarbon offsets and using as model input stable isotope data (δ¹³C and δ¹⁵N), the performance of two Bayesian mixing model instances (routed and concentration‐dependent model versus non‐routed and concentration‐independent) was compared to predict the carbon contribution of marine foods to bone collagen. Predictions generated by both models were in good agreement with observed values. The model with higher complexity showed only a slightly better performance in terms of accuracy and precision. This demonstrates that under similar circumstances, a simple Bayesian approach can be applied to quantify the carbon contribution of marine foods to human bone collagen.     

The consilience of historical and isotopic approaches in reconstructing the medieval Mediterranean diet

During the Middle Ages, the economies of Europe, the religious directives involving dietary requirements, and the general human subsistence base were transformed. These complicated and intertwined issues are starkly revealed in an isotopic study of two inland Italian human populations that are separated by approximately 850 years in time. Stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotopic values observed in human dentin and bone collagen from the sites of early medieval Castro dei Volsci and late medieval Rome are consistent with diets that differed substantially. As the North Atlantic opened to fishing and food preservations methods improved, Mediterranean peoples increased their fish consumption dramatically, and in doing so, met the religious directives of the Catholic Church. By analyzing both teeth and bone collagen within individuals, long-term feeding behaviors are documented, and the utility of last erupted teeth collagen as sources of adult dietary information is established. This study offers the first physical evidence of this new economic reality linking the Atlantic and Mediterranean economies at the end of the Middle Ages.     

Reassessing the diet of Upper Palaeolithic humans from Gough's Cave and Sun Hole,Cheddar Gorge,Somerset, UK

Richards et al. (2000) reconstructed the diet of the human remains found in Gough's and Sun Hole Cave through isotope analysis. They concluded that these people consumed an entirely terrestrial-based diet. Their reconstruction was based upon comparison of the results from human bones with those from a very small number of associated animals. The diets of the Gough's and Sun Hole Cave human were different from the other six Upper Palaeolithic humans from the British Isles for which dietary information has been obtained through isotope analysis. The work of Richards et al. (2000) suggests that they were the only ones for whom marine or freshwater resources did not play a significant role in their diets. We test this through further analyses of faunal remains from Gough's Cave, Sun Hole and other contemporary sites (Kent's Cavern, Aveline's Hole, Kendrick's Cave). Despite the limited faunal sample, the original palaeodietary reconstruction is broadly consistent with our findings. The isotope values of the main protein sources consumed by the humans from both sites are consistent with those of red deer and bovines, and, for a single individual, with that of horse and red deer. Reindeer was postulated in the original reconstruction as a potential food source, but this seems very unlikely based on our isotope reconstruction and the archaeological remains.     

Stable isotope analysis of humans from Xiaojingshan site: implications for understanding the origin of millet agriculture in China

Millet agriculture originated in Northern China in the early Neolithic period (ca. 8000 BP), however, the actual importance of millet in human diets is still not clear. To determine the relative contribution of millet in human diets in this period we undertook stable isotope analysis of humans from Xiaojingshan site and fauna from Yuezhuang site, both of which are attributed to the Houli Culture and date to about 8000 years ago. The carbon isotope values of human bone collagen showed that millet (as a C₄ plant) only contributed approximately 25% of dietary protein, with the rest from C₃ based plant and animal sources, if a simple mixing model is used. We did not observe any statistical dietary difference between males and females at the site, although it has been argued that the Houli Culture was a matriarchal society. Finally, we compared our data with other published isotopic data from the contemporary Jiahu site and Xinglongwa site and a number of sites from the subsequent Yangshao Culture and found that millet only became a significant source of dietary protein approximately 1000 years later, as human carbon isotope values from these later sites indicated that almost all of dietary protein came from C₄ (i.e. millet) sources.     

Evaluation of carnivory in inland Jomon hunter–gatherers based on nitrogen isotopic compositions of individual amino acids in bone collagen

Archaeological studies including stable carbon and nitrogen isotope analyses of bone collagen from human remains have suggested their heavy dependence on terrestrial foods during the Jomon period in the inland central region in Japan. However, it is not easy to quantitatively evaluate the extent of carnivory for archaeological human remains based on the bulk collagen chemistry, because of variable ¹⁵N-enrichment factor along the trophic step and background isotopic variations in ecosystems. In order to overcome these problems and more precisely evaluate diets of prehistoric humans who strongly adapted to terrestrial environment, in this study we applied nitrogen isotope analysis of individual amino acids in bone collagen to two inland human populations in the Jomon period. Our results suggest that the two populations were predominantly dependent on the C₃-plant-based terrestrial ecosystem and consumed little aquatic resources. Furthermore, their mean trophic positions (2.7 for both cases) are closer to that of the fox (2.8–3.0) rather than those of pure herbivores (2.0–2.2), and show little change over time. These results are the first evidence that inland Jomon populations may have had more carnivorous diets than is traditionally considered.     

The distinction between freshwater- and terrestrial-based diets: methodological concerns and archaeological applications of sulphur stable isotope analysis

Sulphur isotopes in archaeological bone collagen are not routinely analysed in palaeodietary studies. Here we investigate the potential contribution that sulphur isotope analysis can provide toward the study of ancient human diet and economy, with particular emphasis on the distinction between freshwater and terrestrial consumers. For material from the Late Bronze Age site of Chicha in the south-western Eurasian forest-steppe, sulphur isotopes effectively separate freshwater and terrestrial animal food resources. The sulphur isotope data coupled with nitrogen isotope values from Chicha reflect a dietary reliance upon freshwater animal protein (fish) for the Late Bronze Age inhabitants. In contrast, sulphur isotope values for freshwater and terrestrial potential food species from the Eneolithic site of Bil'shivtsi in western Ukraine were indistinguishable, demonstrating that δ³⁴S values cannot always be relied upon to identify freshwater and terrestrial consumers. The data from this study support the adoption of δ³⁴S analysis as a standard component of palaeodietary studies; apart from its potential to distinguish freshwater from terrestrial consumers, it can provide supplementary dietary information not evident from the carbon and nitrogen isotope data. In addition, certain indices are considered that may be used to assess the validity of sulphur isotope data, as currently exist for carbon and nitrogen. According to the analysis of modern collagen samples, N:S appears to be a broad indicator of collagen sulphur isotope quality. However, more work needs to be done to establish an effective means by which highly-altered sulphur isotope values can be identified and thereby removed from consideration.     

Kana Tamata or Feasts of Men: An Interdisciplinary Approach for Identifying Cannibalism in Prehistoric Fiji

By integrating osteological, taphonomic, archaeological and stable isotopic data, we test for cannibalism in the Lau Group, Fiji and discuss the potential underlying cause(s) and context(s) of this behaviour. First, we compare taphonomic and element representations of human skeletal material from two contexts in Fiji, examining human bone fragments from archaeological sites, including middens and burials in the Lau Island Group. Fourteen sites produced human remains. Only two of those sites included distinct human burial contexts, but in the remaining 12 sites, the human bone was recovered from middens or contexts where midden was mixed with possible secondary burials. A total of 262 number of identified specimens per species, representing an estimated 15 minimum number of individuals make up the Lau human assemblage. Second, we analysed bones contained in 20 individual human burials from four different sites that are housed at the Fiji Museum for comparative purposes. Third, we examine previously published stable isotopic (δ¹³C, δ¹⁵N) analysis of bone collagen to gauge protein consumption of likely cannibalised humans in midden contexts and potential cannibals from primary burials. We model a cannibalistic diet category within the context of isotopically measured Pacific Islands food groups and apply an isotopic mixing model to gauge plausible dietary contributions from six sources including human flesh. Isotopic mixing models of the Lauan samples illustrate a high diversity in reconstructed diets. The percent contribution of human flesh is low for all individual Lauans. We conclude that mortuary rituals evidenced by sharp‐force trauma may suggest non‐nutritive and non‐violent practices that may have included the consumption of small amounts of human flesh. Copyright © 2012 John Wiley & Sons, Ltd.     

Assessing the life history of an andean traveller through biogeochemistry: Stable and radiogenic isotope analyses of archaeological human remains from Northern Chile

Bioarchaeology and biogeochemistry can elucidate aspects of individual life histories that are often lost in the archaeological record. Here, we use stable and radiogenic isotope analyses of enamel, bone and hair to reconstruct paleodiet and paleomobility in an adult male interred along a pre‐Columbian route connecting the northern Chilean coast to the inland Loa River Valley. Although this well‐preserved burial included mortuary goods typical of coastal cultures, it was discovered in a vast, uninhabited part of northern Chile's hyper‐arid Atacama Desert. Variation in carbon and nitrogen isotopes reflects dietary differences, while strontium and oxygen isotopes vary geologically and geographically. We use these data to examine paleodiet and paleomobility and to assess whether this was a coastal traveller seeking provisions from the interior or vice versa. Enamel stable isotope analysis is consistent with the consumption of a mixture of terrestrial and marine resources during the first years of life. Bone stable isotope analyses indicate habitual consumption of marine foodstuffs over the last 10–30 years of this individual's life. Interestingly, stable isotope analysis of hair samples provides more fine‐grained information on this individual, suggesting movements between the coast and highlands in the months before his death. Radiogenic strontium isotope data are consistent with residence on the coast or in the Atacama Desert, but are lower than strontium isotope values from higher altitudes. These dietary and geological patterns are reconcilable with coastal residency; the isotopic data are consistent with foodstuffs and textiles found with the burial. Therefore, we argue that this individual was regularly moving from the coast to inland areas, crossing the hyper‐arid Atacama Desert by following strategic interzonal routes that provided access to particular resources. Copyright © 2010 John Wiley & Sons, Ltd.     

Funeral practices and foodstuff behaviour: What does eat meat mean? Stable isotope analysis of Middle Neolithic populations in the Languedoc region (France)

The aim of this study is to reconstruct the dietary patterns and economic behaviours of Neolithic populations in the Northwestern Mediterranean using isotopic and archaeological data. Burials come from four sites located in Languedoc–Roussillon region in French Mediterranean area. These sites are dated from the Middle Neolithic period (ca. 4500–3500 BC). They represent the Chasséen culture, characterized by regional features, such as economy management, resulting from territorial control. For this investigation, a stable isotopes (δ¹³C and δ¹⁵N) method has been used on 50 human bone collagens and 28 associated animal bones. This method provides direct dietary information on the protein consumed including the relative amounts of marine vs. terrestrial and animal vs. plant proteins in diets. Isotopic results are mainly compared to archaeological data to understand economic distinctions and potential social status variations between different groups using specific funeral practices, i.e. lithic chamber graves vs. domestic/funeral pits. Results show that individuals buried in lithic chamber graves and those buried in pits did not have the same dietary pattern. This result suggests a possible differentiation between two socio-economic groups, i.e. consumers of resources from herding and from farming. No aquatic food appeared to be routinely consumed by these individuals despite a relative close proximity to sea and freshwater sources. Moreover, these outcomes lead us to hypothesize that: (1) funeral practices could be linked to specific economies and/or (2) to different social status and that (3) burial type and foodstuff could be an expression of religious worship. Further research could include data from other areas, such as Spanish Catalonia where there are funeral structures similar to Languedoc lithic chamber graves.     

Carbon and nitrogen stable isotope analysis on the diet of Jomon populations from two coastal regions of Japan

We report on a stable isotope paleodietary reconstruction of Jomon populations in Japan during the Middle to Final Jomon period (ca. 5000–2300 years BP), focusing on dietary differences within and among populations and between regions. Carbon and nitrogen isotope analysis was performed on human and faunal bone collagen from six coastal sites along the Inland Sea in the Sanyo (Ota, Funamoto, and Tsukumo) region and along Mikawa Bay and the Pacific Ocean in the Tokai (Kawaji, Yoshigo, and Inariyama) region. We found that carbon and nitrogen isotope ratios were positively correlated, indicating that the Jomon people consumed a mixed diet of marine (shellfish and marine fish) and terrestrial (C₃ plants and terrestrial mammals) protein. In the Ota samples (n = 25, during the Middle Jomon period, 5000–4000 years BP), sex was one of the main reasons for the intra-population dietary variation. Ota males consumed greater amounts of marine food, while Ota females consumed greater amounts of terrestrial food; these dissimilar diets may have been related to the sexual division of labor. Significant inter-population dietary differences were found, which may have been related to differences in age or site location. Notably, the two coastal regions showed clear isotopic differences. Nitrogen isotope ratios of individuals from the Sanyo region were significantly higher than ratios of individuals from the Tokai region. The individuals in the Sanyo region might have consumed a diet high in aquatic foods, particularly high trophic level marine fish, whereas the individuals in the Tokai region might have consumed a lot of marine shellfish. Another possible reason for the regional isotopic difference might have been different baseline of nitrogen isotope ratios of the marine ecosystems.     

Evaluation of bone strontium as a measure of seafood consumption

The recognition that bone strontium/calcium ratios reflect dietary levels of strontium and that seawater has a high strontium content led some archaeologists to infer that seafood consumption produces high Sr/Ca ratios in bone. Analyses of seawater and of marine organisms reveal, however, a marine trophic effect comparable to the trophic effect seen in terrestrial food chains. This marine trophic effect reduces the Sr/Ca levels in seafood such that marine dietary resources have Sr/Ca levels comparable to those of terrestrial resources. Thus, bone Sr/Ca ratios can not differentiate consumption of marine and terrestrial resources. Also, Sr/Ca of bones from archaeological sites where seafood was an important component of diet were found to be within the range of entirely terrestrial diets. Copyright © 1999 John Wiley & Sons, Ltd.