Results Of Stable Isotope Analyses Research Articles

Parasite Dynamics: One Pattern and Multiple Possible Causes

How is parasitism likely to respond to anthropogenic global change? Digenean trematode prevalence among bivalve mollusk hosts in multiple coastal environments has been linked to sea-level rise on centennial and millennial time scales. Previous efforts have ruled out the influence of changing diversity, community structure, taphonomy, and salinity (fossil-based proxy) on this pattern but, until recently, we have not been able to address the role of other abiotic environmental factors. Here we present the results of stable isotope analyses (δ18O and δ13C) of the shallow marine bivalve Chamelea gallina from the Holocene and modern northern Adriatic (Italy) and trace element analysis of the estuarine bivalves Potamocorbula amurensis and Corbicula formosana from the Holocene Pearl River (China) delta using Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). Generalized Linear Models (GLM) of 1,297 δ18O and δ13C analyses from 57 C. gallina valves derived from 11 modern death assemblages and four Holocene core samples reveal that elevated trematode prevalence is associated with relatively negative δ18O values, relatively positive δ13C values, and a high correlation between δ18O and δ13C values. We interpret this to mean that trematode prevalence is higher during warm temperatures with minimal freshwater influence. GLMs of 3,295 LA-ICP-MS spot analyses on 48 valves from the two estuarine species (a separate GLM for each taxon), derived from 12 cored samples from Pearl River deposits, reveal a strong association between trematode prevalence and elevated Ba/Ca ratios and low species richness, which we interpret as high parasitic infestation of an oligotypic community in hypoxia-dominated environments. Taken together, the results suggest that parasitic patterns are linked to sea-level rise and geochemical insights point toward case-specific causal factors that are going to be more widespread due to anthropogenic climate change.

Scotland's first farmers: new insights into early farming practices in North-west Europe

Thirty years after the discovery of an Early Neolithic timber hall at Balbridie in Scotland was reported inAntiquity, new analysis of the site's archaeobotanical assemblage, featuring 20 000 cereal grains preserved when the building burnt down in the early fourth millennium BC, provides new insights into early farming practices. The results of stable isotope analyses of cereals from Balbridie, alongside archaeobotanical and stable isotope results from three other sites, indicate that while cereals were successfully cultivated in well-established plots without manuring at Balbridie, a variety of manuring strategies was implemented at the other sites. These differences reinforce the picture of variability in cultivation practices across Neolithic North-west Europe.

The first data on the human diet in Late Roman and Early Migration period western Lithuania: Evidence from stable isotope, archaebotanical and zooarchaeological analyses

This study presents the results of stable isotope analyses performed on human tooth enamel (δ13C), bone collagen (δ13C and δ15N), and animal bone and tooth dentine collagen (δ13C and δ15N). We sampled archaeological material from Late Roman and Early Migration period settlement and burial sites in western Lithuania. Stable isotope analysis of human teeth demonstrated that human diet was primarily based on herbivorous and omnivorous domestic animals and C3 plants. Also, we established that social stratification was not reflected in the isotopic data. Finally, the data presented in this paper revealed that human diet remained extremely uniform during the Late Roman and Early Migration periods.

Trophic ecology of elasmobranch and teleost fishes in a large subtropical seagrass ecosystem (Florida Big Bend) determined by stable isotope analysis

Carbon and nitrogen stable isotope analyses were used to infer relative trophic structure and examine regional variation in trophic dynamics of fishes in the Florida Big Bend, an approximately 300 km stretch of relatively pristine coastline in the eastern Gulf Of Mexico that contains over 250,000 ha of seagrass. The Florida Big Bend is home to a diverse assemblage of fauna; and the ecosystem is regionally important through its support of robust fishing (recreational and commercial) and eco-tourism industries. Stable isotope analyses suggest assemblages of fishes in the Florida Big Bend are trophically diverse, with considerable isotopic overlap across many taxa. Patterns of trophic structure corroborated the results of similar studies of these and related taxa and in other seagrass ecosystems, and there appear to be multiple channels of primary production. Large elasmobranch fishes were most enriched in δ 15N with values well above the teleost fishes sampled, while smaller and demersal elasmobranchs had δ 15N signatures comparable to several species of predatory teleosts. Results of stable isotope analyses suggested high trophic redundancy and overlap in resource use among both teleost and elasmobranch fishes. Comparisons of regional stable isotope values revealed some spatial variability and indicated the southern Big Bend is isotopically distinct, suggesting a distinct regional faunal zone in this region, potentially due to greatly reduced river influence in the southern portion of the system.

Multi-isotopic analysis of dietary habits and mobility at third millennium BC Bakla Tepe, West Anatolia

This paper examines the dietary habits and mobility of an Early Bronze Age (3000–2000 BCE) population from Bakla Tepe (West Anatolia in the Izmir region). The research utilises the results of stable isotope analyses of carbon (δ13C), nitrogen (δ15N), and sulphur (δ34S) from human bone collagen in conjunction with published archaeological data. Intra-population issues of dietary habits such as possible social divisions (e.g. between sexes, ages, and socio-economic status) were addressed. The sample population from Bakla Tepe consists of 19 adults and no subadults. In total, there are 8 males (42.1%) and 11 females (57.9%). There are two distinct and separate period cemeteries; from the Early Bronze Age I period, 7 individuals were sampled, with 12 individuals sampled from the Early Bronze Age II/III period. The results show that during the 3rd millennium BCE, dietary habits were generally homogeneous and became more so in the latter part of the millennium. Diets were predominantly terrestrial C3 based. There is one individual whose δ34S value suggests that she moved to the settlement from a location further inland and another whose δ34S value suggests that she may have moved to the settlement from nearer the coast.

Analysis of dietary habits in a prehistoric coastal population from İkiztepe, North Turkey, using stable isotopes of Carbon, Nitrogen, and sulphur

This paper examines the dietary habits of a Late Chalcolithic-Early Bronze Age (ca. 3200–2800 BCE) population from İkiztepe. Intra-population issues of dietary habits such as possible social divisions (e.g. between sexes, ages, and socio-economic status) were addressed.The research utilises the results of stable isotope analyses of carbon (δ13C), nitrogen (δ15N) and sulphur (δ34S) from human and animal bone collagen in conjunction with published archaeological data. Analysis of sulphur was conducted to investigate possible marine and freshwater resource consumption. The sample population from İkiztepe consists of 38 adults: 19 males and 19 females. A total of 20 (12 males and 8 females) adult individuals were sampled for the δ34S analysis.For sulphur (δ34S) the range in the sampled adult population is from 6.8‰ to 11.5‰. The respective means for δ13C and δ15N are −20 ± 0.3‰ and 8.9 ± 0.5‰. There is a greater range in the values of δ13C (1.4‰ compared to 0.9‰) and δ15N (2.6‰ compared to 1.9‰) for females, and males predominantly have δ15N values above 9.3‰.The dietary habits of the population were terrestrial C3 based and lacked significant marine or freshwater input despite the proximity of the settlement to the Black Sea and estuary of the Kızılırmak River. Furthermore, males had a slightly greater protein input than females in their diet. Animal management strategies and the exploitation of secondary products are also suggested.

Dietary habits in the Early Bronze Age (3rd millennium BC) of Anatolia: A multi-isotopic approach

This paper presents the results of isotopic analysis for dietary reconstruction of humans and animal remains from several prehistoric (3500–2000 BCE) populations in Anatolia. The investigated sites are İkiztepe (north Anatolia, Samsun region, on the Black Sea coast), Titriş Höyük (south east Anatolia, Urfa region), Bademağacı (south Anatolia, Antalya region), and Bakla Tepe (south west Anatolia, in the İzmir region). This research utilises the results of stable isotope analyses of carbon (δ13C), nitrogen (δ15N), and sulphur (δ34S) in bone collagen from over 200 human and animal samples in conjunction with published archaeological, archaeobotanical, and archaeozoological data (where present) to address this issue. This study, for the first time, has permitted a wider observation of Early Bronze Age dietary habits and subsistence strategies across the region, as well as examining the nature of dietary habits on an intra- and inter-site level, and temporally across the 3rd millennium BC. The results show that during the EBA in Anatolia there was a general degree of homogeneity in dietary habits at an intra- and inter-site and regional level and across the millennium of the EBA with diets being predominantly terrestrial C3 based.

Hydrodynamic and isotopic niche differentiation between juveniles of two sympatric cryptic bonefishes, Albula vulpes and Albula goreensis

We employed numerical wave models, GIS, and stable isotope analyses of otolith material to identify interspecific differences in habitat and resource use among juveniles of two sympatric and morphologically indistinct bonefishes, A. goreensis and A. vulpes in littoral zones of The Bahamas. Both species occurred in similar water temperatures; however, A. goreensis juveniles occupied habitats characterized by greater wave-driven flow velocities and closer proximity to coral reefs than A. vulpes. Likewise, A. goreensis was present across a broader range of flow environments and sampling stations than A. vulpes, which was typically confined to sheltered, low-flow habitats. The results of stable isotope analyses were consistent with the species’ relationships with environmental parameters, providing support for differential habitat and/or resource utilization. Otolith δ18O did not differ significantly between species, suggesting they experience comparable thermal regimes. However, δ13C varied substantially, with the otoliths of A. goreensis depleted in 13C relative to A. vulpes by approximately 1‰, potentially signifying a greater reliance on pelagic carbon sources by the former, in agreement with observed distinctions in habitat use. In linear models, otolith δ13C was negatively correlated with ambient flow velocity and positively related to distance from coral reef habitats, and these relationships did not vary across species. After accounting for the effects of these variables, species-specific differences in otolith δ13C remained, indicating that other unknown factors contributed to the observed disparities. Collectively, our findings suggest that niche partitioning between A. goreensis and A. vulpes is likely mediated by their differential abilities to compete across various flow environments, likely as a result of divergent behavioral and/or physiological adaptation.

The use of hydrogeochemical analyses and multivariate statistics for the characterization of thermal springs in the Constantine area, Northeastern Algeria

This paper deals with the results of a hydrogeochemistry study on the thermal waters of the Constantine area, Northeastern Algeria, using geochemical and statistical tools. The samples were collected in December 2016 from twelve hot springs and were analyzed for physicochemical parameters (electric conductivity, pH, total dissolved solids, temperature, Ca, Mg, Na, K, HCO3, Cl, SO4, and SiO2). The waters of the thermal springs have temperatures varying from 28 to 51 °C and electric conductivity values ranging from 853 to 5630 μS/cm. Q-mode Cluster analysis resulted in the determination of two major water types: a Ca–HCO3–SO4 type with a moderate salinity and a Na–K–Cl type with high salinity. The plot of the major ions versus the saturation indices suggested that the hydrogeochemistry of thermal groundwater is mainly controlled by dissolution/precipitation of carbonate minerals, dissolution of evaporite minerals (halite and gypsum), and ion exchange of Ca (and/or Mg) by Na. The Gibbs diagram shows that evaporation is another factor playing a minor role. Principal Component Analysis produced three significant factors which have 88.2% of total variance that illustrate the main processes controlling the chemistry of groundwaters, which are respectively: the dissolution of evaporite minerals (halite and gypsum), ion exchange, and dissolution/precipitation of carbonate minerals. The subsurface reservoir temperatures were calculated using different cation and silica geothermometers and gave temperatures ranging between 17 and 279 °C. The Na–K and Na–K-Ca geothermometers provided high temperatures (up to 279 °C), whereas, estimated geotemperatures from K/Mg geothermometers were the lowest (17–53 °C). Silica geothermometers gave the most reasonable temperature estimate of the subsurface waters overlap between 20 and 58 °C, which indicate possible mixing with cooler Mg groundwaters indicated by the Na–K–Mg plot in the immature water field and in silica and chloride mixing models. The results of stable isotope analyses (δ18O and δ2H) suggest that the origin of thermal water recharge is precipitation, which recharged from a higher altitude (600–1200 m) and infiltrated through deep faults and fractures in carbonate formations. They circulate at an estimated depth that does not exceed 2 km and are heated by a high conductive heat flow before rising to the surface through faults that acted as hydrothermal conduits. During their ascent to the surface, they are subjected to various physical and chemical changes such as cooling by conduction and change in their chemical constituents due to the mixing with cold groundwaters.

A genetic model based on evapoconcentration for sediment-hosted exotic-Cu mineralization in arid environments: the case of the El Tesoro Central copper deposit, Atacama Desert, Chile

Although the formation of exotic-Cu deposits is controlled by multiple factors, the role of the sedimentary environment has not been well defined. We present a case study of the El Tesoro Central exotic-Cu deposit located in the Atacama Desert of northern Chile. This deposit consists of two mineralized bodies hosted within Late Cenozoic gravels deposited in an arid continental environment dominated by alluvial fans with sub-surficial ponded water bodies formed at the foot of these fans or within the interfan areas. Both exotic-Cu orebodies mostly consist of chrysocolla, copper wad, atacamite, paratacamite, quartz, opal, and calcite. The most commonly observed paragenesis comprises chrysocolla, silica minerals, and calcite and records a progressive increase in pH, which is notably influenced by evaporation. The results of stable isotope analyses (δ13C and δ18O) and hydrogeochemical simulations confirm that evapoconcentration is the main controlling factor in the exotic-Cu mineralization at El Tesoro Central. This conclusion complements the traditional genetic model based on the gradual neutralization of highly oversaturated Cu-bearing solutions that progressively cement the gravels and underlying bedrock regardless of the depositional environment. This study concludes that in exotic-Cu deposits formed relatively far from the source, a favorable sedimentary environment and particular hydrologic and climatic conditions are essential to trap, accumulate, evapoconcentrate, neutralize and saturate Cu-bearing solutions to trigger mineralization. Thus, detailed sedimentological studies should be incorporated when devising exploration strategies in order to discover new exotic-Cu resources, particularly if they are expected to have formed relatively far from the metal sources.

Social status in late medieval and early modern Brittany: insights from stable isotope analysis

We document for the first time the diet of a privileged French population from Brittany, a region that was the center of battles between the Kingdoms of England and France until the end of the fifteenth century. We present here the results of stable isotope analyses of carbon, nitrogen, and sulfur of human and animal bone and tooth collagen for a late medieval to early modern Breton population. The isotopic values observed for the Dominican convent of Rennes, Brittany, are very similar to those reported for medieval archaeological populations in Great Britain, namely they have enriched δ15N values combined with almost entirely terrestrial carbon signals. We discuss the consumption of young animals in a diet made up of terrestrial, marine, and freshwater resources. We report dietary differences between socio-economic groups and gender, with women and nobles (male and female) showing patterns consistent with high animal product consumption and lower mobility. The S isotope ratios of both humans and fauna are very homogeneous and generally have coastal δ34S values. The convent is known to have been an interregional pilgrimage site during the early modern period, but the isotope values indicate that the identified migrants were not pilgrims. Stable isotope analysis therefore complements the available historical information on human diets and mobility.

Diet composition changes in tigerfish of Lake Kariba following an invasion by redclaw crayfish

The present study used a combination of stable isotope techniques and stomach content analyses to examine the diet and ontogenetic diet shifts of tigerfish, Hydrocynus vittatus , in the Sanyati basin of Lake Kariba, Zimbabwe. We compared tigerfish diet shifts in the presence of an invasive crayfish, Cherax quadricarinatus , with previous studies before invasion. Here, we assessed whether tigerfish now had a preference for C. quadricarinatus leading to a shift in its main dietary food sources from cichlids to crayfish. The dominance of cichlids has remained generally high when compared with historical assessments. Stable isotope analyses showed that tigerfish fed on a variety of food sources including those that may be temporarily unavailable. Results of stable isotope analyses also highlighted that C. quadricarinatus was now becoming an important food source across all tigerfish size classes. In conclusion, tigerfish in Lake Kariba showed remarkable dietary plasticity and ontogenetic shifts, identified by both stomach content and stable isotope analyses.

Child Health in Five Early Medieval Irish Sites: A Multidisciplinary Approach

AbstractWith the aim to reconstruct child health in five early medieval (5th–12th c. CE) Irish sites, an osteoarchaeological study of three biological stress indicators – cribra orbitalia, linear enamel hypoplasia (LEH) and periostitis – has been conducted on 229 skeletons. In addition, Irish early medieval written sources testifying on child health during this period were consulted. These data were furthermore combined with the results of stable isotope analyses (nitrogen and carbon) conducted on subadult bone specimens. Cribra orbitalia was found in 27.5% of the studied individuals (48.6% of subadults were affected), with only two cases active at the time of death. The prevalence of LEH per individual is 63.5% (78.9% in subadults and 59.7% in adults). The age ranges of LEH formation vary between 1.9 and 4.8 years for the maxillary teeth and between 1.8 and 6.2 years for the mandibular teeth. Periosteal inflammations were recorded in over one third of the studied subadults (36.2%) with six cases active at the time of death. The stable isotope results suggest a diet based on terrestrial food sources, with little or no marine input. The presented data strongly suggest that most of the individuals were exposed to a high level of physiological stress during their childhood, and as such does not support the so called ‘osteological paradox’ hypothesis. The observed disturbances were probably caused by a synergistic effect of various biological and socio‐cultural factors. Although the historical records indicate certain differences in diet and lifestyle between social classes and the sexes, this study showed that the children of all ages had poor health in all social classes across a wide geographical location for the full time period of the early medieval. Copyright © 2016 John Wiley & Sons, Ltd.

Isotopic and chemical composition of precipitation in Riyadh, Saudi Arabia

Only limited data on the isotopic and chemical composition of Riyadh rain are currently available. In this study, we complement these data by analyzing integral samples covering 28 precipitation events between 2009 and 2013. Results of stable isotope analyses are used to establish a Local Meteoric Water Line: δ2H=5.22(±0.38)·δ18O+14.8(±0.9) ‰. Moisture source-related isotopic fingerprints are masked by the continental effect, the altitude effect, sub-cloud evaporation, and moisture recycling. The study of one event for intra-storm variability revealed strong isotopic depletion due to rainout and Rayleigh distillation processes, thus highlighting the general need for integral samples. Tritium analyses of grab samples from 12 events yielded concentrations between 2.8 and 6.4tritium units (TU), which are close to the natural background of a few TU.Major ion concentrations and ratios indicate that solutes are predominantly derived from atmospheric dust originating from limestone outcrops and sabkha deposits. The latter play a role with respect to the elevated Cl−and Na+ contents, but are probably also responsible for the SO42−and a part of the Ca2+ found in Riyadh rain. Observed intra- and inter-storm variabilities of major ion levels necessitate the collection of integral samples and the calculation of precipitation-weighted means, respectively.The obtained isotopic signatures and the precipitation-weighted mean Cl−concentration (9.5mgL−1) may be useful in groundwater assessments, e.g., for the identification of modern recharge and quantification thereof by means of the Chloride Mass Balance method.

Stable isotope evidence for diet in early medieval Great Moravia (Czech Republic)

The 9th–early 10th century AD witnessed the rise and fall of the first Slavic proto-state formation, Great Moravia, centered largely in the Morava River basin in today's Czech Republic. Archaeological evidence demonstrates that this early medieval polity depended on an intensive agricultural base, but we know relatively little about the diets actually consumed by the Great Moravian people. Here we report the results of stable isotope analyses of carbon (δ13C) and nitrogen (δ15N) on bone collagen from 33 human and 18 faunal remains from the Kostelisko cemetery, located within the sub-castle sector of the Mikulčice settlement agglomeration along the lower Morava River valley. Results indicate that the Mikulčice–Kostelisko diet was based largely on terrestrial resources, including both plant-derived and animal-derived protein. Elevated δ13C values for humans suggest that millet was an important dietary resource, while elevated δ15N values suggest that animal-derived products also contributed to dietary protein.

Provenancing of unidentified corpses by stable isotope techniques – presentation of case studies

Stable isotope methods can be used to determine the provenance of unidentified corpses. Body tissue materials such as teeth, bone, hair and nail taken from mortal remains provide information of different time periods of an individuals' life from childhood to death. Tissues of newborns contain provenance information of different time periods during pregnancy of the child's mother.The results of stable isotope analyses of body residues of two adults and a newborn found in Germany between 2010 and 2012 are presented. To determine the geographic origin and movements of unknown individuals, stable isotopes of hydrogen, carbon, nitrogen and sulphur were analysed in hair and bone collagen samples. Amino acid composition and, as a consequence, δ2H, δ13C, δ15N, and δ34S values in human keratin and bone collagen are different. Consequently correction factors were determined to compare isotopic data of bone collagen with those of an extensive worldwide reference hair collection. The isotopic signatures in hair and in bone collagen samples were compared to geographical groups of reference hair samples by canonical discriminant analysis. The results served as the basis for providing provenance constraints for the unidentified persons as requested by the police and prosecution. Ultimately the individuals were identified; hence the isotopic provenance interpretations can be critically evaluated and are shown to be successful.

Isotope record of environmental changes at the Skaliska Basin during the Late Glacial and Holocene

ABSTRACT The results of isotopic investigations of the Skaliska Basin sediments are presented. Stable isotope analyses were done for authigenic carbonates from three profiles: W1 - Piotrowo-Ławniki, W2 - Sąkieły Małe, and W4 - Budzewo. The profiles contain carbonate silts at the bottom, then calcareous detritus gyttja and organic silts and peat at the top. Palynological data indicate that sediment were accumulated in the Skaliska Basin from the final phase of the Younger Dryas to the Subboreal period. The values δ18O change from ca −9.4 to −4.5‰, and δ13C values varies from −5.1 to +0.1‰. Such a large range of isotopic data reflects changing conditions in the basin during accumulation of deposits (different water levels, water temperatures, and bioproduction). Based on the results of stable isotope analyses of the carbonates, isotopic zones (Is) were defined and characterized for each profile. The results of isotopic analysis enabled reconstruction of varying environmental conditions connected with lake deepening and/or influx of water enriched in light isotopes, climatic warming, and increase of biological activity. The Late Glacial deposits are characterized by δ18O values of ca −6.5-6‰ and δ13C of ca −1‰. In the transitional time between the Late Glacial and the Holocene, δ18O systematically falls below −8‰, reflecting a substantial change in the isotopic composition of the lake water, likely caused by to inflow of melt water. During the Preboreal period the δ18O as well as the δ13C values systematically decrease and reach minima (−8.4-9.4‰ for δ18O and ca −3.5-4.7‰ for δ13C). At the beginning of the Boreal period, an increase of ca 2‰ in δ18O is noted and is associated with climatic warming. During the Atlantic period the varying trends in the δ18O record are likely connected with changing precipitation/evaporation ratios, causing changes in the isotope composition of the water. The fluctuations of the isotopic values in the upper parts of the successions probably point to shallowing of the lake due to sedimentary infill.

Hydrochemical and stable isotopic characterization of shallow groundwater system in the crystalline basement terrain of Ekiti area, southwestern Nigeria

Assessments of hydrochemical quality and recharge source are critical components of sustainable groundwater resources evaluation and management, especially in complex weathered/fractured crystalline bedrock terrains. Assessment of the weathered/fractured basement aquifer of Ekiti area, SW-Nigeria was undertaken with emphasis on hydrochemical quality and stable isotope characterization of shallow groundwater system. The study approach involved field sampling and in situ measurements of physico-chemical parameters followed by hydrochemical and stable isotope analyses of the water samples. In situ measurements revealed EC value of 43–995 μS/cm (av 431.96 μS/cm) and total hardness of 31.3–295.1 mg/L. The pH of the water sample ranged from 7.0 to 8.9 (av 8.00). The concentrations of the major cations are in the order of Ca2+ > K+ > Na+ > Mg2+ with their respective average values of 33.35, 25.61, 24.91 and 8.7 mg/L respectively while that of the anions are in the order of HCO3− > Cl− > SO42− > NO3− with their respective average values of 165.44, 31.85, 21.27 and 5.44 mg/L respectively. However, the results of stable isotope analyses revealed δ18O value of −4.2 to −2.1 ‰ and δD of −22.3 to −10.2 ‰, suggesting meteoric water source (recent precipitation water recharging the associated shallow basement aquifer) while the estimated deuterium excess of 6.80–11.00 ‰ (av 9.6 ‰) suggested little or no imprint of kinetic evaporation. Furthermore, the overall hydrochemical profiles revealed the main hydrochemical facies as Ca(Mg)-HCO3 (dominant) and Na(K)-HCO3 (minor) water types which can be attributed to dissolution of minerals in the various rock units in the study area. Conclusively, the overall hydrochemical and stable isotope evaluations revealed a recharge predominantly derived from meteoric (rainfall) source while the corresponding low TDS is a reflection of low water–rock interaction and limited migratory history of the shallow groundwater system in the study area.

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.

The Oxfordian stable isotope record (δ18O, δ13C) of belemnites, brachiopods, and oysters from the Kachchh Basin (western India) and its potential for palaeoecologic, palaeoclimatic, and palaeogeographic reconstructions

The study combines the results of stable isotope (δ13C, δ18O) analyses of 187 belemnites, brachiopods, and oysters from the Middle to Upper Jurassic (Upper Callovian to Kimmeridgian) of the Kachchh Basin in western India. Generally, belemnites show lower δ13C and higher δ18O ratios than the benthic fauna. It is proposed that this discrepancy is caused by different life habitats of both groups with belemnites spending major parts of their life in deeper water outside the Kachchh Basin and entering shallow areas only occasionally (e.g., during seasonal migrations to spawning grounds). A mode of life as fast-swimming, nektonic predators similar to many modern squid species seems plausible. The study emphasises that results of stable isotope analyses should be evaluated separately for each fossil group. In addition to the influence of diagenetic alteration, weathering, salinity changes, and sea-level fluctuations, the ecology of the analysed fossil taxa has to be considered. Temperatures calculated from δ18O ratios point to relatively warm conditions around the Middle to Late Jurassic transition with no evidence for a glacial phase which had been proposed for this boundary. A distinct fall in temperatures is observed during the Middle Oxfordian reaching a minimum in the early Late Oxfordian. It is tempting to connect this event with the break-up of Gondwana causing stronger upwelling in the northwestern Tethys or alternatively the influx of polar water by the opening of the Transgondwanan Seaway. However, such connections cannot be verified without further data, preferably from localities in the southern Malagasy Gulf (e.g., Madagascar) and from younger horizons (Kimmeridgian–Tithonian).