Early Colonial Diet in El Japón, Xochimilco, Mexico: Examining dietary continuity through stable isotope analysis of bone collagen and bioapatite.

OBJECTIVES: Early colonial documents from central Mesoamerica detail raising and planting of European livestock and crops alongside native ones. The extent to which Indigenous people, especially of the rural commoner class, consumed newly introduced foods is less known. This gap in knowledge is addressed through stable isotope analysis and comparison to published archaeological botanical, human, and faunal data. MATERIALS AND METHODS: Stable isotope analysis of bone collagen and bioapatite is applied to 74 skeletal samples of Indigenous human remains representing Colonial period individuals from El Japón-a farming hamlet in the Xochimilco area-to provide insight into long-term individual dietary practices in the context of a rapidly transforming Mesoamerican world. RESULTS: Carbon isotope ratios in collagen (δ13Ccollagen) average -8.10/00 VPDB (SD 0.55), while δ15N averages 8.90/00 AIR (SD 0.50). δ13Cbioapatite averages -2.90/00 VPDB (SD 0.60). Modest increase in carbon isotopic diversity is observed among more recent males from El Japón when compared to earlier males and females. DISCUSSION: Based on the isotopic results, it is estimated that the individuals of El Japón consumed maize or other C4 plants as a central source of carbohydrates. Dietary protein was largely supplied through domestic maize-fed fauna but potentially supplemented by wild terrestrial and aquatic fauna and fowl. Similarity in skeletal isotopic composition between precontact Mesoamericans from other sites and El Japón individuals of both earlier and later stratigraphy is interpreted as continuity in local diets and foodways despite potentially available European alternatives. Colonial taxation demands on preexisting agricultural regimes may have incentivized maize production, thus indirectly contributing to the maize-centered aspect of local foodways.

OBJETIVOS: Los textos de la época colonial temprana del centro de México documentan la producción de cultivos y ganado europeo a la par de los productos agropecuarios nativos. La magnitud a la cuál las comunidades indígenas consumieron estos productos se conoce con menos certeza en especial dentro de los asentamientos rurales. En este trabajo, se analiza la variabilidad de datos de isótopos estables en el sitio El Japón, Xochimilco y los resultados se comparan con respecto al sexo biológico y la cronología; así como también con datos publicados de muestras humanas y faunísticas. MATERIALES Y MÉTODOS: Se aplican los estudios de isotopos estables en colágeno y bioapatita a 74 muestras esqueléticas de El Japón de la época colonial temprana, una aldea agrícola del área de Xochimilco, con tal de abordar las practicas dietéticas en el contexto de un mundo Mesoamericano en transformación tras el contacto europeo. RESULTADOS: Los isótopos estables de carbono en colágeno (δ13Ccollagen) producen un promedio de −8.10/00 VPDB (DE 0.55), mientras tanto los isótopos estables de nitrógeno en el mismo tejido producen un promedio de 8.90/00 AIR (DE 0.50). Los isótopos estables de carbono en la bioapatita (δ13Cbioapatite) producen un promedio de −2.90/00 VPDB (DE 0.60). Se observa un incremento mínimo en la diversidad isotópica entre los individuos de sexo masculino en comparación a los individuos de sexo femenino de la etapa temprana y tardía del sitio. DISCUSIÓN: Con base en los resultados isotópicos, y con base en comparación a muestras humanas de contextos arqueológicos europeos y norteamericanos se estima que los individuos de El Japón consumieron maíz u otros cultivos tipo C4 como fuentes principales de carbohidratos. Las fuentes de proteína dietética posiblemente fueron fauna alimentada con maíz, pero también se pudieron haber suplementado con alimentos silvestres incluyendo aves silvestres, y fauna terrestre o acuática. La similitud en variación isotópica entre sitios mesoamericanos que preceden el contacto europeo y El Japón de ambas etapas (temprana y tardía) se interpretan como persistencia en fuentes de alimentación y tradiciones culinarias a pesar de las posibles alternativas europeas. Las demandas tributarias coloniales sobre la producción agrícola chinampera pudiesen haber contribuido indirectamente a la continuidad del maíz como fuente alimenticia principal.

Exploring the effects of weaning age on adult infectious disease mortality among 18th-19th century Italians.

OBJECTIVES: The developmental origins of health and disease (DOHaD) hypothesis describes how early childhood stress affects morbidity and mortality later in life. The role of early childhood stress in mortality from infectious disease is understudied. Stressors in early childhood that weaken the immune system may result in increased susceptibility to infectious disease in adulthood. Weaning is one of the earliest potential periods of significant stress in early childhood. This research investigates the effect of weaning after ~6 months of age on cholera mortality among 18th-19th-century Italian populations by determining if earlier breastfeeding cessation is associated with earlier mortality, analyzing childhood dietary variation and physiological stress markers, and determining if age-at-weaning completion differs between catastrophic and attritional populations. METHODS: Serial dentin stable carbon and nitrogen isotope analyses from canines are compared between catastrophic (n = 45) and attritional groups (n = 23). Canines are sectioned serially from crown to apex, and the increment's δ15 N and δ13 C are used to estimate age-at-weaning completion. RESULTS: Catastrophic and attritional groups exhibit similar age-at-weaning completion (~2.8 years). Seventy-four percent of individuals lack elevated δ15 N values in dentin that formed during infancy. CONCLUSIONS: Age-at-weaning completion was not a predisposing factor in cholera mortality in adulthood in this sample. Age-at-weaning completion may not be significantly associated with infectious disease mortality because weaning completion likely occurred after infants had adapted to consuming contaminated weanling foods. Individuals without detectable weaning curves may represent infants who received supplementary foods since birth or were weaned before the age of 6-9 months.

The diverse genetic origins of a Classical period Greek army.

Trade and colonization caused an unprecedented increase in Mediterranean human mobility in the first millennium BCE. Often seen as a dividing force, warfare is in fact another catalyst of culture contact. We provide insight into the demographic dynamics of ancient warfare by reporting genome-wide data from fifth-century soldiers who fought for the army of the Greek Sicilian colony of Himera, along with representatives of the civilian population, nearby indigenous settlements, and 96 present-day individuals from Italy and Greece. Unlike the rest of the sample, many soldiers had ancestral origins in northern Europe, the Steppe, and the Caucasus. Integrating genetic, archaeological, isotopic, and historical data, these results illustrate the significant role mercenaries played in ancient Greek armies and highlight how participation in war contributed to continental-scale human mobility in the Classical world.

Isotopic evidence for geographic heterogeneity in Ancient Greek military forces.

Increased mobility and human interactions in the Mediterranean region during the eighth through fifth centuries BCE resulted in heterogeneous communities held together by political and cultural affiliations, periodically engaged in military conflict. Ancient historians write of alliances that aided the Greek Sicilian colony Himera in victory against a Carthaginian army of hired foreign mercenaries in 480 BCE, and the demise of Himera when it fought Carthage again in 409 BCE, this time unaided. Archaeological human remains from the Battles of Himera provide unique opportunities to test early written history by geochemically assessing the geographic origins of ancient Greek fighting forces. We report strontium and oxygen isotope ratios of tooth enamel from 62 Greek soldiers to evaluate the historically-based hypothesis that a coalition of Greek allies saved Himera in 480 BCE, but not in 409 BCE. Among the burials of 480 BCE, approximately two-thirds of the individuals are non-local, whereas among the burials of 409 BCE, only one-quarter are non-local, in support of historical accounts. Although historical accounts specifically mention Sicilian Greek allies aiding Himera, isotopic values of many of the 480 BCE non-locals are consistent with geographic regions beyond Sicily, suggesting Greek tyrants hired foreign mercenaries from more distant places. We describe how the presence of mercenary soldiers confronts prevailing interpretations of traditional Greek values and society. Greek fighting forces reflect the interconnectedness and heterogeneity of communities of the time, rather than culturally similar groups of neighbors fighting for a common cause, unified by "Greekness," as promoted in ancient texts.

Bioarchaeological reconstruction of physiological stress during social transition in Albania.

OBJECTIVE: We test the hypothesis that physiological stress increased in response to increasing social turmoil following waves of colonization and social transition. The ways local conditions, including variation in geography, environment, and levels of urbanization impact physiological stress are also explored. MATERIALS: In Albania, the historic period is a sequence of different waves of colonization. Skeletal data come from three Albanian archaeological sites: Apollonia (n = 231), Durrës (n = 246), and Lofkënd (n = 129). METHODS: Prevalence of cribra orbitalia, porotic hyperostosis, linear enamel hypoplasia, and periosteal new bone formation are analyzed using chi-square and logistic regression tests. RESULTS: We observe increased skeletal manifestations of physiological stress between prehistoric and historic groups, but physiological stress is generally consistent through time. CONCLUSIONS: General increase in skeletal pathology between prehistoric and historic periods corresponds to broad increases in political unrest associated with colonization spanning the entire historic period. However, little difference in physiological stress across colonization episodes (Greek, Roman, Byzantine, Bulgarian, Ottoman) suggests skeletal health is affected similarly by colonization, regardless of particularities in method and type of colonial control. SIGNIFICANCE: Examining human response to social change across broad time scales is useful in identifying broad patterns in the human experience. LIMITATIONS: Exploring variation across broad time scales and multiple sites is potentially problematic because confounding factors could impact results and interpretations. SUGGESTIONS FOR FURTHER RESEARCH: Environmental, social, and geographic differences, likely impacted the lives and lifestyles of individuals living in the past and should be explored further to understand the nuances in local response to colonization.

Isotopic and elemental corroborates for wild bearded capuchin (Sapajus libidinosus) omnivorous dietary adaptation at Fazenda Boa Vista, Brazil.

RATIONALE: This study analyzes variability in the diets of wild bearded capuchin monkeys, Sapajus libidinosus, by analyzing stable carbon (δ13 C) and nitrogen (δ15 N) isotope ratios and elemental concentrations (%C and %N) of fecal samples and food items. Developing isotopic and elemental correlates for diets of habituated subjects is a necessary step towards applying similar methods to interpret diets of unhabituated or cryptic subjects. METHODS: Fecal samples from wild capuchins and their foods were collected at Fazenda Boa Vista, Brazil. Fecal samples from laboratory-housed Sapajus spp. and their foods were analyzed to establish diet-feces offsets for δ13 C, δ15 N, %C, and %N. Samples were dried, powdered, and measured for isotopic and elemental values. A Bayesian mixing model commutes isotopic and elemental data from wild capuchins into likely proportions of different food categories. RESULTS: The captive study shows small diet-feces spaces for Sapajus spp. of -0.8 ± 0.7‰ for δ13 C, -0.2 ± 0.4‰ for δ15 N, -6.1 ± 1.7% for %C, and -1.0 ± 0.6% for %N. The wild study shows omnivorous diets based on C3 , C4 , and CAM plants, and fauna. Subject diets are highly varied within and between days. Fecal data show age-related differences in diet and crop-raiding. There is no consistent isotopic or elemental difference between mothers and infants. CONCLUSIONS: Fecal stable isotope and elemental evidence employed in a Bayesian mixing model reflects the highly varied diets of capuchin monkeys in an isotopically heterogeneous environment. The isotopic and elemental variability reported here will aid similar diet reconstructions among unhabituated subjects in the future, but precludes tracking weaning isotopically among capuchins in this environment.

Examining the osteological paradox: Skeletal stress in mass graves versus civilians at the Greek colony of Himera (Sicily).

OBJECTIVES: Bioarchaeologists interpret skeletal stress as evidence of resilience or frailty, where absence of lesions might result from lack of exposure to pathogens (i.e., good health) or extreme vulnerability (i.e., selection). We examine physiological stress in two skeletal series from Greek Himera: (1) nine mass graves from the battles of Himera (480 and 409 BCE) and (2) Himeran civilians (648-409 BCE). Civilians are assumed to have died from multiple causes, including ill health leading to their deaths. Individuals from the battles presumably died while in relatively good health, in battle. More skeletal stress among civilians than battle casualties would support the idea that skeletal stress is a sign of frailty at Himera. We compare variation in skeletal stress between and among civilians and battle casualties. MATERIALS AND METHODS: Cribra orbitalia, porotic hyperostosis, linear enamel hypoplasia (LEH), and sub-periosteal new bone formation, were examined in 474 individuals (mass graves n = 64; civilians n = 410). RESULTS: Chi-square tests showed significantly higher prevalence of LEH (p = 0.04) and sub-periosteal new bone formation (p = 0.05) among young and mid-aged adult male civilians than mass grave casualties. Skeletal stress was also lower in the earlier battle, and varied among civilians with burial style. DISCUSSION: Our findings generally support the hypothesis that skeletal stress is evidence of frailty (i.e., leading to greater risk of mortality). However, the relationship between stress and frailty is complicated by social factors, when considering historical context. In particular, a possible "soldier-class" may have experienced less stress than the overall civilian population.

Subadult dietary variation at Trino Vercellese, Italy, and its relationship to adult diet and mortality.

OBJECTIVES: Early-life nutrition is a predisposing factor for later-life outcomes. This study tests the hypothesis that subadults from medieval Trino Vercellese, Italy, who lived to adulthood consumed isotopically different diets compared with subadults who died before reaching adulthood. We have previously used a life history approach, comparing dentine and bone of the same adult individuals ("subadults who lived"), to elucidate dietary variation across the life span. Here, we examine diets of "subadults who died" from the same population, estimated from subadult rib collagen, to explore whether dietary behaviors of subadults who lived differed from those of subadults who died. METHODS: Forty-one subadults aged six months to 14.5 years were studied through stable carbon and nitrogen isotope analysis of collagen. RESULTS: Individuals were weaned by age 4 years, with considerable variation in weaning ages overall. Post-weaning, diets of subadults who died comprised significantly less animal protein than diets of subadults who lived. Isotopic values of the two oldest individuals, 13.5 and 14.5 years, show the same status-based variation in diet as do adults from the population. CONCLUSIONS: Our results suggest that incorporating animal protein in diet during growth and development supported medieval subadults' ability to survive to adulthood. Isotopic similarities between adults and older subadults suggest "adult" dietary behaviors were adopted in adolescence. Stable isotope evidence from subadults bridges a disparity between ontogenetic age categories and socioculturally meaningful age categories in the past, and sheds light on the underpinnings of health, mortality, growth, and disease in the bioarchaeological record. Am J Phys Anthropol 160:653-664, 2016. © 2016 Wiley Periodicals, Inc.

Inter-individual variation in weaning among rhesus macaques (Macaca mulatta): Serum stable isotope indicators of suckling duration and lactation.

Weaning is a transition in early development with major implications for infant survival and well-being, and for maternal lifetime reproductive success. The particular strategy a primate mother adopts in rearing her offspring represents a negotiation between her ability to invest and her need to invest, and can be considered adaptive and influenced by biological and social factors. Any investigation into how and why maternal weaning strategies differ among non-human primates is limited by the precision of the measurement tool used to assess infants' weaning ages. Stable carbon and nitrogen isotope analysis of soft tissues (e.g., hair, nails, feces, urine, blood) offers an objective means of monitoring the weaning status of infants. In this study, we assess stable isotope ratios in blood serum from 14 captive rhesus macaque dyads (Macaca mulatta) at infant ages 2, 5, 6, 7, 8, and 10 months to estimate the timing of weaning events. Male infants wean earlier than female infants. Infants with the lowest birth weights wean latest. Most infants wean upon reaching 2.5 times their birth weights, sooner than when weaning elsewhere has been predicted for captive cercopithecine primates. The longest weaning periods (ca. 10 months) are observed among infants of small mothers. The shortest weaning period, between 2 and 5 months, was among the lowest ranking dyad. Parity and mothers' ages had no discernible effect on the timing of weaning events. The stable carbon and nitrogen isotope values of dams during lactation are significantly different than those of a non-lactating adult female outgroup, raising questions about the suitability and selection of adult comparative baselines in studies where lactating mothers cannot be sampled longitudinally (e.g., bioarchaeology; paleontology). Am. J. Primatol. 78:1113-1134, 2016. © 2015 Wiley Periodicals, Inc.

Advances in primate stable isotope ecology-Achievements and future prospects.

Stable isotope biogeochemistry has been used to investigate foraging ecology in non-human primates for nearly 30 years. Whereas early studies focused on diet, more recently, isotopic analysis has been used to address a diversity of ecological questions ranging from niche partitioning to nutritional status to variability in life history traits. With this increasing array of applications, stable isotope analysis stands to make major contributions to our understanding of primate behavior and biology. Most notably, isotopic data provide novel insights into primate feeding behaviors that may not otherwise be detectable. This special issue brings together some of the recent advances in this relatively new field. In this introduction to the special issue, we review the state of isotopic applications in primatology and its origins and describe some developing methodological issues, including techniques for analyzing different tissue types, statistical approaches, and isotopic baselines. We then discuss the future directions we envision for the field of primate isotope ecology. Am. J. Primatol. 78:995-1003, 2016. © 2015 Wiley Periodicals, Inc.

Laboratory and field methods for stable isotope analysis in human biology.

Stable isotope analysis (SIA; carbon, hydrogen, nitrogen, sulfur, and oxygen) of human tissues offers a means for assessing diet among living humans. Stable isotope ratios of broad categories of food and drink food vary systematically, and stable isotope ratios in consumer tissues represent a composite of the isotopic ratios of food and drink consumed during an individual's life. Isotopic evidence for diet is independent of errors in informant recall, and accrues during time periods when researchers are absent. Beyond diet reconstruction, tissue stable isotope ratios are sensitive to excursions from homeostasis, such as starvation and rapid growth. Because of their relationship to diet, geographic location, hydration, and nutritional status, stable isotope signatures in human tissues offer a window into human biocultural adaptations, past and present. This article describes methods for SIA that may be usefully applied in studies of living humans, with emphasis placed on carbon and nitrogen. Some of the ecological, physiological, and evolutionary applications of stable isotope data among living humans are discussed. By incorporating SIA in research, human biologists facilitate a productive dialog with bioarchaeologists, who routinely use stable isotope evidence, mingling different perspectives on human biology and behavior.

Growth velocity and weaning δ(15)N "Dips" during ontogeny in Macaca mulatta.

OBJECTIVES: A "dip" in the stable nitrogen isotope ratios (δ(15)N) of subadults in the late weaning/early post-weaning phase of growth and development has been observed. Speculatively, this is the mechanism of positive nitrogen balance operating among rapidly growing subadults. An alternate hypothesis for δ(15)N dips is that during weaning, subadults eat lower-(15)N foods than adults. METHODS: This study explores the role of positive nitrogen balance in affecting δ(15) N variation of growing subadults by comparing growth velocity with stable carbon isotope (δ(13)C) and δ(15)N ratios of blood serum from captive rhesus macaques (Macaca mulatta) (n = 14) with controlled diets during the first 10 months of life. RESULTS: During the first six months, δ(15)N values are inversely correlated with growth in some of the anthropometrics (weight and sagittal circumference). Dips in some infants' δ(15)N values below their mothers' values are observed at the end of the weaning period. However, during this time frame, δ(15)N values of the infants are not correlated with anthropometric indices. Serum stable isotope ratios of lactating and non-lactating adult females differ significantly. CONCLUSIONS: Growth in body mass and size explains some of the variation in infant δ(15)N values, but are not responsible for dips in the late weaning/early post-weaning phase. It is advised that future research evaluate the extent to which growth in other body systems affects nitrogen balance and δ(15)N dips during ontogeny, and expand on isotopic differences between lactating and non-lactating females.

Reconciling "stress" and "health" in physical anthropology: what can bioarchaeologists learn from the other subdisciplines?

The concepts of "stress" and "health" are foundational in physical anthropology as guidelines for interpreting human behavior and biocultural adaptation in the past and present. Though related, stress and health are not coterminous, and while the term "health" encompasses some aspects of "stress," health refers to a more holistic condition beyond just physiological disruption, and is of considerable significance in contributing to anthropologists' understanding of humanity's lived experiences. Bioarchaeological interpretations of human health generally are made from datasets consisting of skeletal markers of stress, markers that result from (chronic) physiological disruption (e.g., porotic hyperostosis; linear enamel hypoplasia). Non-specific indicators of stress may measure episodes of stress and indicate that infection, disease, or nutritional deficiencies were present in a population, but in assessing these markers, bioarchaeologists are not measuring "health" in the same way as are human biologists, medical anthropologists, or primatologists. Rather than continue to diverge on separate (albeit parallel) trajectories, bioarchaeologists are advised to pursue interlinkages with other subfields within physical anthropology toward bridging "stress" and "health." The papers in this special symposium set include bioarchaeologists, human biologists, molecular anthropologists, and primatologists whose research develops this link between the concepts of "stress" and "health," encouraging new avenues for bioarchaeologists to consider and reconsider health in past human populations.

Beyond diet reconstruction: stable isotope applications to human physiology, health, and nutrition.

Analysis of stable carbon and nitrogen isotopes from soft or mineralized tissues is a direct and widely-used technique for modeling diets. In addition to its continued role in paleodiet analysis, stable isotope analysis is now contributing to studies of physiology, disease, and nutrition in archaeological and living human populations. In humans and other animals, dietary uptake and distribution of carbon and nitrogen among mineralized and soft tissue is carried out with varying efficiency due to factors of internal biology. Human pathophysiologies may lead to pathology-influenced isotopic fractionation that can be exploited to understand not just skeletal health and diet, but physiological health and nutrition. This study reviews examples from human biology, non-human animal ecology, biomedicine, and bioarchaeology demonstrating how stable isotope analyses are usefully applied to the study of physiological adaptation and adaptability. Suggestions are made for future directions in applying stable isotope analysis to the study of nutritional stress, disease, and growth and development in living and past human populations.

Introducing fecal stable isotope analysis in primate weaning studies.

This research investigates the potential of a new, noninvasive method for determining age of weaning among primates using stable carbon and nitrogen isotope ratios in feces. Analysis of stable isotope ratios in body tissues is a well-established method in archeology and ecology for reconstructing diet. This is the first study to investigate weaning in primates using fecal stable isotope ratios. Diets of a single François' langur (Trachypithecus francoisi) mother-infant pair at the Toledo Zoo are reconstructed using this technique to track changes in infant suckling behavior over the weaning period. Stable isotope ratios in feces are sampled instead of more traditional samples such as bone or hair to enable daily, noninvasive snapshots of weaning status. Isotopic assessments of weaning status are compared to visual assessments to identify any discordance between the two. Three measurements documented the transition from breast milk to solid foods: stable carbon isotope ratios (δ(13)C), stable nitrogen isotope ratios (δ(15)N), and nitrogen content of feces (%N). It appears that solid foods were introduced at approximately 2 months of infant age, but that nursing continued into the 12th month, when sample collection ceased. Stable isotope data exposed a much longer weaning period than what was expected based on previously published data for captive langurs, and clarified visual estimates of weaning status. This reflects the method's sensitivity to suckling at night and ability to distinguish actual nursing from comfort nursing. After testing this method with zoo animals, it can readily be applied among wild populations. An isotopic approach to weaning provides a new, accurate, and biologically meaningful assessment of interbirth intervals, and facilitates a better understanding of mother-infant interactions. Both of these outcomes are critical for developing successful conservation strategies for captive and wild primates.

Stable isotope evidence for sex- and status-based variations in diet and life history at medieval Trino Vercellese, Italy.

The medieval period in Europe was a time of unprecedented social complexity that affected human diet. The diets of certain subgroups-for example, children, women, and the poor-are chronically underrepresented in historical sources from the medieval period. To better understand diet and the distribution of foods during the medieval period, we investigated stable carbon and nitrogen isotope ratios of 30 individuals from Trino Vercellese, Northern Italy (8th-13th c.). Specifically, we examined diet differences between subgroups (males and females, and high- and low-status individuals), and diet change throughout the life course among these groups by comparing dentine and bone collagen. Our results show a diet based on terrestrial resources with input from C(4) plants, which could include proso and/or foxtail millet. Diets of low-status males differ from those of females (both status groups) and of high-status males. These differences develop in adulthood. Childhood diets are similar among the subgroups, but sex- and status-based differences appear in adulthood. We discuss the possibility of cultural buffering and dietary selectivity of females and high-status individuals.

Brief communication: oxygen isotopes as a biomarker for sickle-cell disease? Results from transgenic mice expressing human hemoglobin S genes.

The origins of sickle-cell disease (SCD) are well understood, as are its evolutionary pressures on humans and pathological presentation. However, because it has not been possible to identify SCD in archaeological contexts, its biocultural effects on past populations are unknown. Previous research investigating oxygen isotope fractionation during respiration among anemics suggests that oxygen isotopes in bone apatite may provide a biological marker for SCD in skeletal remains. This pilot study reports δ(18) O ratios in bone apatite of transgenic laboratory mice expressing human SCD globins and compares them to healthy control mice. The δ(18) O ratios of sick mice are significantly lower than those of healthy mice (-5.6‰ vs. -4.5‰; P = 0.002), and the sickest mice exhibit the lowest ratios of all (mean δ(18) O = -5.8‰). These preliminary results suggest that this method may be usefully applied to skeletal materials of past human populations whose diets and water sources do not differ substantially.