Prehistoric migration at Nebira, South Coast of Papua New Guinea: New insights into interaction using isotope and trace element concentration analyses

Migration is a commonly used explanation for cultural change in world prehistory, and is also a central theme in the prehistory of the Pacific Islands. However it is rarely subject to direct archaeological research. This paper applies strontium and oxygen radiogenic/stable isotope (⁸⁷Sr/⁸⁶Sr, δ¹⁸O), and trace element concentration (Ba/Sr) analyses to 27 individuals buried at the archaeological site of Nebira (ca.720–300 BP), located inland on the South Coast of Papua New Guinea. The analyses seek to identify non-local individuals within the population and provide a more in-depth understanding about the social identity of the possible migrants in this community.The strontium isotope data indicates that five individuals were non-local to Nebira, having possibly come from a coastal location. Correlation with biological data, such as age and sex, also indicates that the pattern of migration at Nebira was not sex or age specific. The results support the archaeological findings that suggest the inhabitants from Nebira were in contact with coastal communities during a period in prehistory of increased cultural interaction. However, despite the considerable isotopic variation identified in the Nebira sample, it is also demonstrated that more research is needed to identify the possible origins of these non-local individuals.     

Carbon and nitrogen isotope composition of natural pastures in the dry Puna of Argentina: a baseline for the study of prehistoric herd management strategies

This study represents an isotopic survey of modern plants developed to establish baseline isotopic values in order to explore prehistoric herd management strategies employed by the South American camelid herders that occupied the southern Andean highlands during the past 3000 years. We present carbon (δ¹³C) and nitrogen (δ¹⁵N) isotopic compositions of natural pastures collected from different plant communities along an altitudinal gradient in the dry Puna of Argentina. Our results show that C₃ plants are the most abundant along the whole altitudinal gradient and that C₃ and C₄ plants exhibit a differential distribution, the latter being less abundant in those sites located above 3900?meters above sea level (masl). At the same time, plants growing at low-altitude sites with low water availability exhibit higher δ¹⁵N values than plants growing at high-altitude sites with higher water availability. These results explain the negative correlation found between altitude and South American camelid bone collagen δ¹³C and δ¹⁵N values published in previous studies. This work represents a fundamental step towards the building of an isotopic ecology for the dry Puna area with the ultimate goal to explore herd management strategies employed by human groups in the past. In this sense, modern plant and South American camelid tissue isotopic compositions would provide a frame of reference to interpret isotopic compositions measured on archaeofaunal remains recovered at pastoral sites, with the aim to explore mobility and pastureland use by prehistoric herders.     

Stable isotopes and diet at Ancient Kerma,Upper Nubia (Sudan)

Carbon and nitrogen stable isotope values were measured from bone collagen extracted from archaeological Nubian human (n = 54) and faunal (n = 61) populations from the site of Kerma, Sudan. Collagen suitable for isotopic analysis was extracted from 22 faunal and 48 human samples from the Eastern cemetery site, dated to the Middle Kerma (c. 2050–1750 BC) and Classic Kerma (c. 1750–1500 BC) periods respectively. The isotopic data indicate that the human dietary regimen included a mix of C₃ and C₄ plant-derived components, with a larger C₄ component than previously reported in archaeological Egyptian Nile Valley populations. Elevated δ¹⁵N values are attributed to consumption of dietary resources from a ¹⁵N-enriched terrestrial ecosystem. The faunal isotope data also indicate the consumption of C₃ and C₄ plants. The large range of δ¹³C values measured in both the human and faunal samples supports previous work suggesting that a significant portion of the populations buried at Kerma may have originated elsewhere, further confirming the Nile Valley as a major corridor for population movement in the region.     

A palaeodietary investigation of carbon (C/C) and nitrogen (N/N) in human and faunal bones from the Copper Age cemeteries of Varna I and Durankulak,Bulgaria

Stable isotope analyses have been applied to human and faunal bone collagen from the Varna I and Durankulak cemeteries to explore palaeodietary adaptations in the Neolithic and Eneolithic (Copper Age). The results suggest both populations primarily utilised terrestrial, C₃-based diets, despite their proximity to the Black Sea. The wider δ¹⁵N range of the Durankulak humans likely indicates the differential utilisation of terrestrial meat sources, which is probably related to the degree to which primary and/or secondary ovicaprid products were consumed, particularly since ovicaprid δ¹⁵N values differ from other herbivores. The isotopic distribution of Varna I reflects a linear relationship between δ¹⁵N and δ¹³C, suggesting that a minority of individuals enriched in both isotopic parameters supplemented their diets with marine resources. These burials include the well known ‘chieftain’ (burial 43) and show notable material wealth by way of grave goods. At the population level, however, there is no significant correlation between stable isotope values and material wealth at Varna I, a fact with implications for theories regarding emergent social/economic hierarchies in Balkan prehistory. Five burials at Durankulak were found to have relatively enriched δ¹³C and δ¹⁵N values with respect to the rest of the population. These burials reflect a prominently marine-based or mixed terrestrial C₃-based diet that included C₄ inputs, possibly from millet, for which the limitations of stable isotope analysis on bulk collagen are not able to differentiate. AMS dating has shown that these burials belong to a much later period.     

Distinguishing sheep and goats using dental morphology and stable carbon isotopes in C4 grassland environments

Distinguishing between sheep and goats in C₄ grass environments using new dental morphology criteria and enamel bioapatite stable carbon isotope ratios (δ¹³C) was tested on 35 modern individuals from the Central Rift Valley of Kenya. Two morphological criteria on the second and third lower molars, one of which had been previously partially described by Halstead et al. [Journal of Archaeological Science 29 (2002) 545], were found to be highly reliable in this population. Identification of species using carbon isotope ratios is made possible in some circumstances by differences in the feeding behavior of sheep, which are mainly grazers, and goats, which are mainly browsers. In environments where C₄ grasses predominate, sheep include a higher proportion of C₄ plants in their diet, and thus have higher δ¹³C values than goats. In the present study, the annual range and seasonal variation of carbon isotope ratio of diet of sheep and goats was measured from intra-tooth sequential analysis. Although the ranges of goat and sheep δ¹³C values overlap, those higher than −3.4‰ all belong to sheep; values lower than −5.2‰ all belong to goats. There is no overlap of the mean δ¹³C values by tooth, which range from −11.8‰ to −4.2‰ for goats, and from −3.1‰ to −1.3‰ for sheep. These results suggest that carbon isotope analysis of bone collagen and/or apatite will also distinguish sheep from goats in tropical C₄ grasslands. Application of the δ¹³C criteria to archaeological material must be restricted to C₄-dominated environments, and where potential access to C₃ plants (mobility, foddering) can be assessed. The utility of these morphological and isotopic criteria for differentiating sheep and goat breeds in other regions remains to be evaluated.     

Patterns of Resource Use and Isotopic Niche Overlap Among Guanaco (Lama guanicoe), Pampas Deer (Ozotoceros bezoarticus) and Marsh Deer (Blastocerus dichotomus) in the Pampas. Ecological,Paleoenvironmental and Archaeological Implications

ABSTRACT

In this paper, we analyze the isotopic niche and resource use of the guanaco (Lama guanicoe), pampas deer (Ozotoceros bezoarticus) and marsh deer (Blastocerus dichotomus) on the temperate plain of the northern Pampa region in the southeast of South America. The measured stable isotope compositions in bone tissue are δ¹³C, δ¹⁵N and δ¹⁸O. All the analyzed samples were recovered from different archaeological sites from the late Holocene. According to the results, the guanaco was strictly confined to the Pampa plain environment, developing a broad niche based on C₃ plants and a variable contribution of C₄ grasses within a grazing trend. The pampas deer preferentially used the Pampa plain, but also the prairies on the borders of the wetland, showing eurioic characteristics and a narrower niche based on C₃ plants. In turn, the marsh deer was strictly confined to wetland environments, developing a C₃ diet–base, within a narrow isotopic niche and stenoic characteristics. The three mammals showed a wide range of intraspecific variability, which was a key factor in their adaptability to spatial and temporal changes in the vegetation coverage. In fact, the temporal trends of their isotopic values were concurrent with the major climatic variations of the Holocene. Differences in the correlations between the values of both carbon sources in both deer species compared with the guanaco suggest a distinct chemical composition of their diet and/or differences in the allocation of nutrients. The isotopic values of nitrogen and spacing of the carbon sources in guanaco (pseudoruminant) and both deer species (ruminants) show no significant differences between them, thus establishing the values for local large herbivores. Significant correlations between δ¹³C and δ¹⁵N were found in the guanaco and marsh deer. The regional and extra–regional variability in the guanaco's δ¹³C_collagen and δ¹⁵N probably reflect the clinal variations in the vegetation coverage and the amount of rainfall. The collagen isotope values in the guanaco throughout the entire Holocene show that the humid Pampa would have shifted between being a more recurrent mesic and temperate plain with minor phases of dry–mesic conditions like during the Little Ice Age, and a humid and warm one at the peaks of the Holocene Thermal Maximum and the Medieval Climatic Anomaly. The guanaco and the pampas deer adapted to all the climatic changes that happened on the humid Pampa until the biological invasions of large European mammals changed the herbivores’ guild composition of this vast plain, pushing them into peripheral habitats due to competition. The within–species variability in isotopic signals through time and space make it necessary to carry out adequate sampling before reconstructing the diets of local past populations.     

Migration and mobility at the Late Lapita site of Reber–Rakival (SAC), Watom Island using isotope and trace element analysis: a new insight into Lapita interaction in the Bismarck Archipelago

This paper uses strontium isotope (⁸⁷Sr/⁸⁶Sr), oxygen isotope (δ¹⁸O) and Ba/Sr trace element data in archaeological tooth enamel samples to investigate migration and mobility at the Late Lapita site of SAC, Watom Island in the Bismarck Archipelago. Previous archaeological models have identified Lapita mobility at a community level using obsidian distribution patterns and changes in ceramic design, whereas isotope and trace element data can potentially reconstruct prehistoric mobility on an individual level. Human and pig teeth were sampled from SAC and a selection of human teeth were included from the Late–Post Lapita site of Lifafaesing, Tanga Islands as a geographic/geological comparison.The results indicate that there is a large amount of isotopic variation in the Bismarck Archipelago which is useful for identifying non-local individuals and possibly determining their origins. One human individual and several pigs were suggested as coming from elsewhere in the region. Three potentially separate locations were identified for the non-local pigs. It is argued, using the data from SAC, that Late Lapita communities in the Bismarck Archipelago were more mobile than previously assumed. The potential for identifying individual migrants in a Lapita context are discussed in terms of assessing the more subtle aspects of Lapita society in the Southwest Pacific Islands.     

Strontium and stable isotope evidence for diet and mobility in Roman Gloucester,UK

This paper presents the results of a multi-isotopic (oxygen, strontium, carbon and nitrogen isotopes) investigation of population and dietary diversity in Roman Gloucester, focusing on individuals found in a late 2nd century AD mass burial pit at London Road, and comparing them to those found in the nearby cemetery. There were no statistical differences in isotopic composition between mass grave and cemetery burials, suggesting, in agreement with the osteological evidence, that the mass burial was the result of a catastrophic event, probably an epidemic disease. Strontium and oxygen isotope analysis demonstrated considerable diversity in the origins of the Gloucester population, with evidence for both UK and non-UK individuals. Diet was predominately terrestrial and similar to that of other Romano-British populations. Elevated δ¹³C_dentine ratios in some individuals are correlated with raised δ¹⁸O_p values and are therefore probably due to childhoods spent in warmer climates, rather than dietary variation.     

Stable Isotopic Analysis of Human Skeletons from the Sunhung Mural Tomb,Yeongju, Korea: Implication for Human Diet in the Three Kingdoms Period

This study reports the results of stable isotope analyses (carbon, nitrogen and sulphur) of human bone collagen from the Sunhung mural tomb from the Three Kingdoms Period of Korea (AD 300–668). The stable isotope data indicate that the main source of protein in the diet of the interred seven Sunhung individuals came from C₃‐based terrestrial resources, and there was an isotopic variation between individuals at this site. To investigate dietary patterns in the Three Kingdoms period, we compared our results with reported isotopic data from other southeastern Three Kingdoms sites (Imdang‐dong, Songhyeon‐dong and Yean‐ri). We found that the Sunhung individuals had similar isotope ratios to the people from these other sites. However, there was noticeable isotopic difference among individuals from each study site, although much of the dietary protein in each site was mainly from terrestrial sources. We propose that the most parsimonious explanation for this isotopic pattern is variation in social status during this time period. Copyright © 2012 John Wiley & Sons, Ltd.     

Stable isotope evidence for dietary and cultural change over the Holocene at the Sabana de Bogotá region,Northern South America

The Sabana de Bogotá in the northern Andes is an interesting region to investigate temporal patterns of dietary variation because it counts with a vast archeological and osteological record for the last 10,000 years. In this paper, stable isotope data of human archeological bone collagen and apatite were used to study the evolution of diet and major subsistence transformations taking place during the Holocene (～9000–600 cal BP). Paleoenvironmental reconstructions and the isotopic ecology of the Sabana de Bogotá were used as an interpretative baseline. Stable isotope measurements (δ¹³C_col, δ¹³C_ap, δ¹⁵N, and Δ¹³C_col-ap) representing hunter-gatherers, horticulturalists, and agriculturalists (N = 134 individuals) were analyzed by using bivariate, regressional, and discriminant statistical techniques. Results show that early Holocene hunter-gatherers (9000–7000 cal BP) consumed mostly C₃ vegetal resources locally available. In contrast, animal protein was less important. Middle Holocene hunter-gatherers (6000–4500 cal BP) continued with the food foraging pattern observed in the earlier counterparts and presented a slight increase in C₃ animal protein intake. During the initial late Holocene ca. 4000 cal BP, important shifts in subsistence strategies occurred when populations presented a trend toward mixed C₃/C₄ diets, and by ca. 3500 cal BP, there is a clear signal of C₄ crops (i.e., maize) consumption concomitant with the introduction of ceramic technology. During the final late Holocene (last 2000 cal years BP), intensive agriculture was adopted and humans presented relatively diverse diets integrated by C₄ and C₃ crops, C₃-C₄ feeding animals, and freshwater resources. Such dietary change coincides with an increase in sociopolitical complexity, population size, and a general decline in health.     

Stable Isotope Analysis of Diet‐based Social Differentiation at Late Prehistoric Collective Burials in South‐Western Portugal

In the Neolithic and Copper Age collective burials of the Portuguese Estremadura, the majority of material culture and skeletal remains are highly commingled, making it difficult for archaeologists to evaluate social status by linking individuals with specific grave goods. In these circumstances, bio‐anthropological data about individual life histories offer an additional avenue of investigation into social complexity among prehistoric communities practising collective burial. In this study, stable isotope data were gathered from 81 individuals from seven collective burial sites and one settlement, the fortified site of Zambujal, in order to determine if significant dietary differences exist within or between burials that may point to patterns of social differentiation, both at individual sites and across the region. While in general all of the sampled individuals consumed fairly homogeneous diets based on terrestrial animal proteins and C₃ plants, this study found that statistically significant differences in δ¹³C_ap and δ¹⁵N values exist between several sites, which may indicate socially differentiated consumption of meat and plants. Additionally, statistically significant differences were found in δ¹⁵N values between adults and juveniles, which may either be attributable to protein‐restrictive child‐feeding practices or physiological processes related to skeletal growth and development.     

Sensitivity of bulk sedimentary stable carbon isotopes to prehistoric forest clearance and maize agriculture

The stable carbon isotope compositions (δ¹³C) of tropical lake sediments and soils have been used to reconstruct the occurrence of prehistoric maize cultivation and its relative importance through time. This study assesses some of the possible variables affecting the response of lake sediment bulk organic carbon isotope (δ¹³C_TOC) values to variations in the scale of prehistoric maize cultivation and the potential of this proxy to yield quantitative estimates of the scale of prehistoric maize agriculture in small tropical watersheds. High resolution analyses of δ¹³C_TOC values, maize pollen concentrations, and mineral influx were conducted on sediments deposited during a ∼220 year period of prehistoric maize agriculture in the watershed of Laguna Castilla, a small lake in the mid-elevations of the Cordillera Central, Dominican Republic. Close correspondence between δ¹³C_TOC values and maize pollen concentrations in the Laguna Castilla sediment record indicates a close relationship between the isotopic values and the scale of prehistoric maize cultivation. Correlations between the δ¹³C_TOC signature and mineral influx indicate that the isotope record is also sensitive to variations in allochthonous carbon delivery. This study establishes that sedimentary δ¹³C_TOC values can provide a highly sensitive proxy of the spatial scale of prehistoric maize agriculture in small tropical watersheds, but emphasizes the need for a better understanding of sediment dynamics and carbon cycling in anthropogenically modified landscapes before this proxy can be widely employed in diverse archaeological settings.     

Macronutrient-based model for dietary carbon routing in bone collagen and bioapatite

Carbon stable isotope ratios (??¹³C), measured in human bone collagen (??¹³C_collagen) and bioapatite (??¹³C_bioapatite), are commonly used indicators in ancient human diet reconstruction. The underlying assumption is that human tissues broadly reflect the ??¹³C signal of dietary food sources (??¹³C_diet) plus an isotopic offset. However, interpretation of results may be confounded by the differentiated routing of macronutrients (energy, that is carbohydrates and lipids, and protein) having associated different isotopic signals (??¹³C_energy, ??¹³C_protein). Multiple regression analyses were conducted on data from controlled animal feeding experiments compiled by Froehle et al. (J Archaeol Sci 37:2662?C2670, 2010). We derived a simple algebraic macronutrient-based model with ??¹³C_bioapatite?=?10.1?+???¹³C_diet (??) and ??¹³C_collagen?=?4.8?+?0.74 ??¹³C_protein?+?0.26 ??¹³C_energy (??). While the established relationship for ??¹³C_bioapatite is similar to previously known results, the model also suggests that ??¹³C_collagen signal contributions originate from surprisingly consistent proportions of protein and energy macronutrients. Given that feeding experiments explore extreme variations in the proportion of diet macronutrients, the applicability of the proposed model and its predictions were tested in a variety of well-known, wild animal and human, natural contexts. Possible biochemical mechanisms explaining these empirical results are discussed.     

Stable isotopic analysis of human bones from Jiahu site,Henan, China: implications for the transition to agriculture

We have investigated change in subsistence during the transition to agriculture in the site of Jiahu, Henan Province, China, using stable isotopic analysis of collagen and apatite in human bones. Millet agriculture is well documented at drier high latitudes of the Yellow River Valley, while rice agriculture predominated at wetter lower latitudes of the Yangtze Valley region. The early Neolithic site of Jiahu lies near the boundary between the drier north and wetter south. Archaeobotanical evidence shows that rice was a significant component of diet at Jiahu, but its δ¹³C value is similar to that of other foods, and therefore cannot be conclusively identified by carbon isotope analysis. Foxtail and broomcorn millets are the only C₄ crops known for the Chinese Neolithic. Because of their high δ¹³C values, their consumption can be evaluated by stable carbon isotope analysis of human bone. Collagen reflects mainly the δ¹³C value of dietary protein, and apatite accurately records that of the whole diet. Isotopic analysis of 15 well-preserved samples from three periods shows that collagen δ¹³C values were very low for almost all individuals, suggesting C₃-based foods dominated their diets. However, apatite carbonate δ¹³C values and δ¹³C spacing between collagen and apatite (Δ¹³C_ap-co) indicate that millet may have been a minor component of the diet in this region. Individuals, who consumed the smallest amounts of animal protein, as indicated by low δ¹⁵N, generally had the highest apatite δ¹³C values. Archaeobotanical evidence for millet at Jiahu is needed to support this interpretation.     

Responding to the second ghetto: Chicago's Joe Smith and Sin Corner

World War Two and its aftermath transformed Chicago's African American community. The Great Migration entered a second and more intense phase as black migrants flooded into Northern cities. This massive relocation of Southern blacks resulted in the expansion and reformulation of Chicago's ghettoes on both the West and South Sides of the city. The question of a response to this Second Ghetto from African Americans themselves presents itself. White politicians, cultural elites and businessmen still controlled the city and could impose their will on its neighborhoods simply redrawing ghetto boundaries to reflect the new realities of the postwar era. The strange case of Joe Smith and Sin Corner sheds some light on black agency in the 1950s. The African American middle class had resources it commanded to try and protect itself from racial injustice. These resources, however, were based on class privileges not enjoyed by most in the African American community.     

Reconstructing faunal migrations using intra-tooth sampling and strontium and oxygen isotope analyses: a case study of modern caribou (Rangifer tarandus granti)

Isotopic analyses of incrementally developed dental tissues can be used to reveal patterns of movement and diet in animals. However, the suitability of these methods for the reconstruction of herd movements has not yet been demonstrated. Inter-individual behavioural and isotopic variability at the herd scale, and the implications for archaeological and palaeocological applications, can only be demonstrated through the testing of modern animals. In this pilot study, dual-element isotopic profiles were created from incrementally developed dental tissues of five individuals selected from a modern herd of migratory Alaskan caribou (Rangifer tarandus granti). Enamel from second and third molars from the individuals was sequentially sampled in order to reconstruct time-series isotopic profiles. Variation in the strontium (⁸⁷Sr/⁸⁶Sr) and oxygen (δ¹⁸O_CARB) isotope ratios of sequentially sampled enamel were compared to documented herd movement patterns and local geological and environmental conditions. Four individuals displayed the same general trends, although absolute isotopic values varied. One individual displays a very different trend and may represent a behavioural outlier or an immigrant from a semi-domesticated reindeer herd. The implications of this study to herd movement reconstruction in the past are discussed.     

Human Response to Climate Change during the Umm an‐Nar/Wadi Suq Transition in the United Arab Emirates

Stable oxygen isotope ratios in archaeological human dental enamel represent an under‐utilised tool in the examination of changing climatic patterns in the ancient world. In the Oman Peninsula at the end of the third millennium bc , rapid aridification was accompanied by a breakdown in interregional trade relations; however, the human response to these changes is poorly understood. At the Bronze Age necropolis at Shimal in the United Arab Emirates, dental enamel from individuals interred in both Umm an‐Nar (ca 2700–2000 bc ) and Wadi Suq (ca 2000–1300 bc ) tombs underwent oxygen, strontium and carbon isotope analyses to examine how local inhabitants of southeastern Arabia responded to both environmental and socioeconomic change. While individuals from Shimal exhibit a clear shift in mean δ¹⁸O_c(VPDB) values from the Umm an‐Nar (−3.5 ± 0.6‰, 1σ) to the Wadi Suq (−2.4 ± 0.9‰, 1σ), corresponding ⁸⁷Sr/⁸⁶Sr and δ¹³C_ap signatures display homogeneity indicative of continuity in Bronze Age lifeways. Together, these data highlight the ability of local communities to successfully adapt to their changing environs (in lieu of societal collapse or a shift to a more mobile lifestyle) in an effort to maintain their way of life. Copyright © 2014 John Wiley & Sons, Ltd.     

Strontium isotopic reconstruction of the composition of an urban free black population from the 19th century United States

The Industrial Revolution in the United States had a tremendous impact on society, altering not only economics but also the distribution of it population. It was also during this period that increasing numbers of African Americans gained their freedom from slavery. Released from overt bondage, free African Americans sought the opportunities denied to them for over two centuries, initiating a large scale movement of people to the burgeoning urban centers of industry. The individuals interred in the Newburgh Colored Burial Ground (1830–1870) represent one small segment of this process. Strontium isotopic analyses are utilized in order to discuss the demographic composition of Newburgh’s free black population during this time period. In particular, we examine the relative contribution of migration and natural increase, and whether there are significant sex-specific differences in the formation of the population. The results suggest that Newburgh’s free black population was composed predominantly of individuals born in the immediate region. Additionally, there were a greater percentage of non-local males than females. While historical data suggests that females had greater job opportunities in the north relative to males, the growing industrial economy Newburgh may very well have fostered greater male mobility.     

The Seasonal Mobility Model for Prehistoric Herders in the South-western Cape of South Africa Assessed by Isotopic Analysis of Sheep Tooth Enamel

A pattern of seasonal mobility between the coast and the hinterland by Khoekhoe pastoralists in the south-western Cape of South Africa was documented at the time of European contact. Because the region is characterized by a mosaic of geological substrates of various ages and vegetation types with different proportions of C₃ and C₄ plants, this mobility model for prehistoric herders can be tested by analysis of carbon, oxygen and strontium isotope ratios in domestic bovid tooth enamel. Isotopic analysis was performed on archaeological sheep, cattle, eland and steenbok teeth from the Late Stone Age site of Kasteelberg on the Vredenburg Peninsula. Sequential sampling of enamel provided a chronological record of the isotopic composition of diet during tooth formation. Results from carbon and oxygen isotope analysis of archaeological and modern steenbok teeth show seasonal variation in the δ¹³C of local pastures in the vicinity of the site (up to 2·9‰ in a single individual), which could be due to seasonal change in proportions of C₃ and C₄ plants and/or seasonal variation in the δ¹³C of C₃ plants. A pattern of seasonal change of 0·9–3·5‰ in the δ¹³C of tooth enamel is also observed in the sheep teeth. This amplitude of variation could be due to local seasonal changes, thus it is not possible, from the δ¹³C values, to infer whether the sheep were moving seasonally. Results from ⁸⁷Sr/⁸⁶Sr analysis of two sheep suggest that one individual stayed all year round on the coast, whereas the other had grazed in the interior for part of its life. Both δ¹³C and ⁸⁷Sr/⁸⁶Sr values measured in a cow tooth suggest that this animal spent part of its life in the interior, even though it died at Kasteelberg. Results on this cow also suggest longer residence within habitats rather than seasonal mobility. A clear pattern of seasonal mobility between the coast and the interior has not been shown for prehistoric pastoralists. However, the pattern of mobility attested in historical times might have developed only later in prehistory, when cattle pastoralism developed in the region.     

Isotopic dietary reconstruction of humans from Middle Bronze Age Lerna,Argolid, Greece

This study presents the results of a carbon and nitrogen stable isotope analysis of 39 human bone and 8 animal samples from Middle Bronze Age (or Middle Helladic, MH, ca. 2100–1700 BC) Lerna, Greece. The isotopic data indicate that the humans had a C₃ terrestrial diet while certain individuals appear to have significant amounts of animal protein in their diet. With regard to weaning age, the isotopic values and the estimated age of early enamel disruptions suggest that solid foods were starting to be used as a substitute for breast milk at or before the ages of 2.5 and 3 years old.