Isotopic Analysis

SUMMARY: Chapter 9, in Renfrew & Bahn's textbook (Archaeology: Theories, Methods, and Practice), covers the various types of trade and exchange in past societies, and how one may assess it, including different types of interactions (e.g., gift exchange), various scientific techniques (e.g., microscopic examination of materials; trace-element analysis; isotopic analysis), studying material and/or artifact distributions, assessing production and consumption, and analyzing the various means of exchange and interaction.  In my view, this is one of the best college textbooks available, and is invaluable for students, archaeologists, and the public in general, to obtain a top notch overview of approaching and interpreting the archaeological record. UPDATED/REVISED March, 2021, some editing and new formatting, minimal new materials.

We present a novel method for nitrogen and oxygen natural isotopic abundance analysis of nitrate and nitrite of seawater and freshwater at environmental concentrations. The method involves the reduction of nitrate to nitrite using spongy cadmium with further reduction to nitrous oxide using sodium azide in an acetic acid buffer. For separate nitrite analysis, the cadmium reduction step is simply bypassed. Nitrous oxide is purged from the water sample and trapped cryogenically using an automated system with subsequent release into a gas chromatography column. The isolated nitrous oxide is then analyzed on a continuous flow isotope ratio mass spectrometer via an open split. This paper describes the basic protocol and reaction conditions required to obtain reproducible natural abundance level nitrogen and oxygen isotopic ratios from nitrate, nitrite, or both, and the results obtained to support these conclusions. A standard deviation less than 0.2‰ for nitrogen and 0.5‰ for oxygen was found for nitrate samples ranging in concentration from 40 to 0.5 µM (better for nitrite), with a blank of 2 nmol for 50-mL samples. Nitrogen and oxygen isotopic fractionation and oxygen atom exchange were consistent within each batch of analysis. There was no interference from any seawater matrixes. Only one other method published to date can measure the nitrate oxygen isotopic abundance in seawater and none that do so for nitrite alone in the presence of nitrate. This method may prove to be simpler, faster, and obtain isotopic information for lower concentrations of nitrate and nitrite than other methods.

1] Abstract: Molybdenum isotopic compositions are precisely determined by MC-ICP-MS measurements using a Mo double spike. The double spike is added prior to chemical purification, so that laboratory and instrumental mass fractionations are separated from natural mass-dependent fractionation. Fractionation is determined on four Mo mass ratios, providing an internal consistency check. The external standard reproducibility is at 0.06 per mil on the 98 Mo/ 95 Mo ratio (2 standard deviation)). Using a normal microconcentric nebuliser with a cyclonic spray chamber, the minimum quantity of Mo is $1 mg for high-precision results. A hydrothermal molybdenite shows fractionation of À0.3 per mil on the 98 Mo/ 95 Mo ratio relative to our standard (Johnson Matthey, 1000 mg/mL (0.3%) ICP standard solution, lot 602332B). Fine-grained sediments show fractionation of 0.1 and À0.3 per mil on the 98 Mo/ 95 Mo ratio. The observed Mo isotope fractionation is small but resolvable with the presented high-resolution technique. , 2001. Determination of molybdenum isotope fractionation by doublespike multicollector inductively coupled plasma mass spectrometry,

Chara hispida forms dense beds (0.78-0.95 kg DW m À2 ) in Colgada Lake. The ability of Chara meadows to act as a nitrogen source or sink was evaluated by the following methods: (1) investigating Chara growth, (2) nitrogen incorporation and decomposition laboratory experiments and relating experimental results to field conditions. Sediment oospores were germinated in large aquaria and observed growth rates were 0.001 m day À1 (shoot length) and 0.0002 g day À1 (dry weight). Nitrogen uptake rates were determined by addition of K 15 NO 3 during two different periods of Chara growth and the rates were 1.21 and 3.86 mM g DW À1 h À1 when charophytes were 166 days old (not sexually mature) and 323 days old (sexually mature), respectively. After the uptake experiments, the same charophytes were allowed to decompose within two types of litter bags (3 mm-pore litter bags and entire, non-porous plastic litter bags). Decomposition rates of Ch. hispida were 0.016 and 0.009 day À1 in perforated and non-perforated bags, respectively, and fit a negative exponential model. The nitrogen release rate, calculated as the disappearance of N content from Chara tissues, was 0.012 day À1 and there were no statistically significant differences between the values from the two different bag types. The dissolved organic nitrogen concentrations in aquarium and non-perforated litter bags waters increased linearly with time due to the leaching of soluble compounds from Chara. The rate of N loss from Chara tissues, total nitrogen and dissolved organic nitrogen release rates and the decrease in initial dry weight rate were all lower than the daily rate of Chara N uptake. By extrapolating laboratory data to field situations, we determined that approximately 38% of the N taken up by charophytes in Colgada Lake during the growth period is retained. Given the high charophyte biomass in the lake, its ability to incorporate nitrogen, its low decomposition rate and its ability to over-winter, we conclude that Chara beds could be acting as nitrogen sinks in this ecosystem. #

This article is of the earliest metal daggers, which in some cases are hardly distinguishable from knives, is compiled in the area between southern Bulgaria (Rohdope mountains), the western Ukraine and Upper Austria (Mondsee). They can be dated to the so called transitional phase between the Eneolithic and the Early Bronze Age according to current Bulgarian terminology. The oldest examples can be placed in the earlier part of the 4th millennium B. C. and are associated with the Bodrogkeresztur Culture. An analysis of the formal aspects of these daggers allows them to be divided into 12 types (with variants), which only partially show genetic connections. The distributions of the individual dagger types do not necessarily correspond to the areas occupied by archaeological cultures defined by pottery. Groupings based on spectral analysis result two main geographic concentrations. Daggers made with arsenic alloys are found in the western Pontic area where as west Carpathian and central Danubian examples show no arsenic inclusions. Interestingly, some Bodrogkeresztur type daggers in Transylvania are made with arsenic alloys, others are not (Arıuşd, Mereşti and Mastacän). Therefore we assume that the daggers first spread from west to east and later dispersed in the opposite direction. The earliest dagger horizon dealt with here, is seen as being a fundamental part of the deep seated changes which lead to the formation of the Early Bronze Age after Aegean terminology.

Post-collisional volcanism in northwestern Iran is represented by the Saray high-K rocks including leucite-bearing under-saturated and leucite-free silica saturated rocks. We report Ar–Ar age data which constrain the age as ca. 11 Ma (late Miocene). Most of clinopyroxene phenocrysts from the volcanic rocks have complex oscillatory zoning, with high Ti and Al cores, low Ti and high Al mantled clinopyroxenes, grading into low Ti and Al outer rims. All the rocks are highly enriched in incompatible trace elements and have identical Sr–Nd–Pb isotopes. Enrichment in incompatible elements and other geochemical features for the Saray lavas suggest a metasomatized sub-continental lithospheric mantle (SCLM) as the magma source. The negative Nb–Ta–Ti anomalies for the Saray lavas compare with the features of subduction-related magmatism with negligible contamination with ancient crustal components. The highly radiogenic 87 Sr/ 86 Sr and 207 Pb/ 204 Pb isotopic values of the Saray lavas imply the involvement of slab terrigenous sediments and/or a continental lithosphere. Isotopically, the volcanic rocks define a binary trend, representing 5–8% mixing between the primary mantle and sediment melts. Our melting models suggest residual garnet in the source and are incompatible with partial melting of amphibole and/or phlogopite bearing lherzolites, although the complex geochemical features might indicate the result of mixing between melts produced by different sources or a homogenous melt passing through a compositionally-zoned mantle during multiple stages of partial melting and melt migration. The geochronological, geochemical and isotopic data for the Saray rocks suggest that these Late Miocene magmas were derived from a small degree of partial melting of subduction-metasomatized (subcontinental) lithospheric mantle source in a post-collisional setting.

1. We assessed the impacts of deforestation on the energy base of headwater food webs in seven headwater streams in the Upper Chattahoochee basin, GA, U.S.A where percentage forest in catchments ranged from 82 to 96%. We measured terrestrial organic matter standing crop and determined consumer (crayfish and insectivorous fish) dependence on terrestrial versus aquatic energy sources via gut content and stable isotope analyses. 2. Standing crop of coarse particulate organic matter (CPOM) declined with deforestation at large scales (i.e. catchment deforestation and riparian deforestation at the entire stream network scale). Terrestrial plant matter, the dominant component of crayfish guts, declined in crayfish guts with reductions in CPOM standing crop and with deforestation. 3. Crayfish and insectivorous fish d 13 C showed enrichment trends with deforestation, indicating isotopic divergence from CPOM, the most 13 C-depleted basal resource, with reductions in catchment and riparian forest cover. Crayfish d 13 C also exhibited enrichment with decreased instream CPOM standing crop. 4. A concentration-dependent mixing model was used to calculate the relative dependence of crayfish and fish on terrestrial versus aquatic basal resources. Results suggested that both allochthonous CPOM and autochthonous production were important basal resources. Consumer dependence on CPOM decreased with reductions in canopy cover. 5. Our data suggest the importance of forest cover to headwater food webs at multiple scales, and that relatively low levels of riparian deforestation along headwater streams can lead to reductions in stream food web dependence on terrestrial subsidies.

The cargo of marble blocks off Capo Bianco was dated to the Roman period. New sampling and analysis has identified Carrara marble, and also Rosso di Francia (Rouge Languedoc) and Portargento, which strongly suggests a post-medieval date. This leads to the suggestion
that nearby finds dating between the second half of the 18th century and the first half of the 19th may come from the same ship, perhaps sailing from France and Liguria to deliver stone in southern Italy. This is rare evidence of the post-medieval marble trade and demonstrates the importance of archaeometric analysis for the interpretation of wrecked cargos.

To honor Aren Maeir on the occasion of his 60th birthday, we present and discuss recently analyzed zooarchaeological data from the Early Bronze Age (EB) IIIB horizon at Tell eṣ-Ṣâfī/Gath (Israel) as a case study. The thoughtful integration of scientific techniques to address a variety of archaeological questions at the site is a key strength of our site director, Prof. Aren Maeir. This work could not have happened without Aren’s strong support and enthusiasm. Our analysis documents how domestic animals were reared, processed, and consumed within an early urban center in the Near East and the relationship of these patterns to the establishment of social and economic hierarchies within the region.

This paper presents a historiographical critique of Hyksos scholarship and the impact of Imperialism and Orientalism on the foundations of such studies. I trace the creation and maintenance of the misconception of the Hyksos as a race through the scholarship, examining the context and influences behind the research, and discuss the appeal of new scientific techniques for question of Hyksos origins.

Trechispora (Hydnodontaceae) is considered as a soil-inhabiting fungus. However, some species in the genus are frequently forming basidiomes on soil, a typical feature of ectomycorrhizal fungi. Ectomycorrhizal basidiomes are found in neotropical and subtropical region, but taxonomical information and DNA sequences of root fungi and basidiomes from native Atlantic Rainforest are poorly reported. Basidiomes and soil samples including roots, humus layer, and mineral soil were collected in the Atlantic Rainforest, in Florianópolis (South of Brazil). Sequences of the ITS region were obtained from all sample types and subjected to phylogenetic reconstruction. Two sequences amplified from apparently ectomycorrhizal roots belonged to Trechispora and suggested a root-associated ecology, at least biotrophic and possibly ectomycorrhizal. The analysis of isotope abundance in the same Brazilian site and in French Guiana showed that Trechispora thelephora has high 15 N abundance and is often intermediate between ectomycorrhizal and saprotrophic species in 13 C abundance. This is congruent with a plant biotrophic ecology, perhaps ectomycorrhizal. Future investigations in subtropical regions are needed to determine whether such a mode of nutrition is widespread among Trechispora.

This article is a little addition to the study of the earliest metal daggers "Die frühesten Metalldolche Südost-und Mitteleuropas. - Praehistorische Zeitschrift 68, 1993/1, 103-145." It is addressed mainly to the dagger from the tomb № 982 of the prehistoric necropolis in Durankulak (Northeastern Bulgaria). Investigations of this dagger is of great importance to the prehistory of Europe. The period in which it occurs is associated with the collapse of one of the most powerful cultural system in Europe, that of late Eneolithic cultures in Bulgaria (about 4200 years BC). Long hiatul chronologically in the second half of IV millennium BC Dobrogea (Northeastern Bulgaria) is again inhabited by tribes coming from Nord Pontic steppes. These people are already aware of an entirely new, progressive method for enrichment of copper ores with a mixture of arsenic (As). This is a completely new technology for Europe and is essential to the Bronze Age.Discovered in a tomb 982 from Durankulak (Northeastern Bulgaria) is discussed in the broader context in reflecting the turbulent historical processes in the second half of IV millennium BC. Arsenic-bronze (As) of which the earliest daggers and axes of the fourth millennium BC, have the same production technology. This progressive technology happens after "hunger for metal," typical of Europe in IV millennium BC and a new "know-how", reached Europe through the migration of northern nomads. The introduction of this technological revolution, which eventually paved the way for the emergence of classical bronze metallurgy.

Stable-carbon and nitrogen isotopic compositions (d 13 C, d 15 N) of baleen plates of two juvenile and four adult gray whales (Eschrichtius robustus) were examined. High variance in isotopic composition of baleen plates was detected among individuals and, unlike other migratory species of baleen whales examined isotopically, d 13 C and d 15 N values of most whales showed no regular oscillations. Only one baleen plate reflected the assumed principal Arctic prey (ampeliscid amphipods) during growth on the summer grounds. The rate of baleen growth inferred for one of the juveniles in the last 5 months of life (4.7 mm/week) was similar to the rate calculated previously for a rehabilitating gray whale calf. Autumn corresponded to the timing of the formation of lowest d 15 N values measured along plates. We estimate that the baleen length in all adult gray whales recorded around a year of information (1.3 ± 0.3; Mean ± SD). This short period of dietary integration precludes long time series analyses in this species and reflects the extensive wear on baleen plates due to benthic foraging.

To evaluate metallurgical processing as a source of Zn and Cd isotopic fractionation and to potentially trace their distribution in the environment, high-precision MC-ICP-MS Zn, Cd and Pb isotope ratio measurements were made for samples from the integrated Zn-Pb smelting and refining complex in Trail, B.C., Canada. Significant fractionation of Zn and Cd isotopes during processing of ZnS and PbS ore concentrates is demonstrated by the total variation in δ 66/64 Zn and δ 114/110 Cd values of 0.42‰ and 1.04‰, respectively, among all smelter samples. No significant difference is observed between the isotopic compositions of the Zn ore concentrates (δ 66/64 Zn = 0.09 to 0.17‰; δ 114/110 Cd = −0.13 to 0.18‰) and the roasting product, calcine (δ 66/64 Zn =0.17‰; δ 114/110 Cd= 0.05‰), due to ∼100% recovery from roasting. The overall Zn recovery from metallurgical processing is ∼98%, thus the refined Zn metal (δ 66/64 Zn = 0.22‰) is not significantly fractionated relative to the starting materials despite significantly fractionated fume (δ 66/64 Zn = 0.43‰) and effluent (δ 66/64 Zn=0.41 to 0.51‰). Calculated Cd recovery from metallurgical processing is 72-92%, with the majority of the unrecovered Cd lost during Pb operations (δ 114/110 Cd= −0.38‰). The refined Cd metal is heavy (δ 114/110 Cd =0.39 to 0.52‰) relative to the starting materials. In addition, significant fractionation of Cd isotopes is evidenced by the relatively light and heavy isotopic compositions of the fume (δ 114/110 Cd= −0.52‰) and effluent (δ 114/110 Cd =0.31 to 0.46‰). In contrast to Zn and Cd, Pb isotopes are homogenized by mixing during processing. The total variation observed in the Pb isotopic compositions of smelter samples is attributed to mixing of ore sources with different radiogenic signatures.

Vegetation inherited from a Pliocene subtropical climate evolved through obliquity oscillations and global cooling leading to modern conditions. An integrated, highly time-resolved record of pollen and stable isotopes (δ 18 O and δ 13 C of Globigerina bulloides) was obtained to understand vegetation responses to Early Pleistocene climate changes. Continental and marine responses are compared in the Central Mediterranean region with a particular consideration of environmental changes during anoxic events.

The stable isotope ratio and seasonal changes in diet of two indigenous (Oreochromis mossambicus, Tilapia rendalli) and one exotic (Oreochromis niloticus) tilapiine cichlids in the subtropical Limpopo River, South Africa were investigated to determine patterns of resource partitioning. Stomach contents of O. niloticus and O. mossambicus indicated high dietary overlap across size class, habitat and season, with both species primarily feeding on vegetative detritus. However, stable isotope analysis revealed that the two Oreochromis species had different stable isotope ratios derived from different food sources. The relatively δ13C-depleted O. niloticus indicates a phytoplankton-based diet, while the δ13C-enriched O. mossambicus indicates a macrophagous diet dominated by vegetative detritus and periphyton. The high similarity in stomach contents and the interspecific differences in isotopic composition reveal fine-scale patterns of food resource partitioning that could be achieved through selective feeding. Tilapia rendalli was largely macrophagous and fed mainly on aquatic macrophytes and had a low dietary overlap with both O. niloticus and O. mossambicus. In the Limpopo River, detritus and algae are probably the most abundant food resources and the causal factors responsible for the observed patterns of resource partitioning among the tilapiines are usually difficult to ascertain. Fish may be able to perceive food resources in terms of the dynamics that determine their availability. Detailed studies of variation in food resource availability and fish habitat use within the system are needed to evaluate this hypothesis.

Stable isotope studies of food webs in floodplains, large rivers, mangroves, and seagrasses have shown that, although a large proportion of the biomass may come from higher plants, microalgae provide a disproportionate amount of carbon assimilated by metazoan consumers. Evidence is building that this may also be the case for streams, especially those in the tropics. At the level of individual consumer species we also see that the apparent diet may not be reflected in the carbon assimilated. Tropical streams commonly have omnivoredetritivore species that potentially show this phenomenon. We tested these concepts in four moderately shaded sites in a stream in well-preserved Atlantic rainforest at Ilha Grande, Rio de Janeiro. We sampled aquatic insects, shrimps and fish as well as potential terrestrial and aquatic primary food sources. Carbon stocks from terrestrial sources predominated over carbon of algal origin (>99% of total). The primary sources of carbon showed distinctly different isotopic signatures: terrestrial sources had δ 13 C values close to −30‰, microalgae were −20‰ and macroalgae were −25‰. All fauna had δ 13 C values consistent with a carbon source derived from microalgae. Baetid mayflies and atyid shrimps exert a strong grazing pressure on periphyton and organic sediments but appear to assimilate predominantly microalgae. The palaemonid shrimp Macrobrachium olfersi also ingests large amounts of detritus of terrestrial origin, but apparently assimilates animal prey with algal δ 13 C signatures. These results support the growing view that tropical stream food chains are primarily algal based.

Excellent dolomite exposures are observed in the eastern Salt Range (Pakistan), where the Cambrian Jutana Formation consists of two distinct units (i.e. oolitic – pisolitic unit and massive dolomite unit). Field observations revealed that the lower, oolitic-pisolitic unit mostly comprises medium to thick bedded, interlayered brown yellowish dolostone containing ooids/pisoids and faunal assemblages, and grey whitish sandstone with distinct depositional sedimentary features (i.e. trough-, herringbone- and hummockycross bedding). The upper massive dolostone unit consists of thick bedded to massive dolostone. These two units are separated by shale. Petrographic studies identified three dolomite types, which include: fine crystalline dolomite (Dol. I), medium-coarse crystalline dolomite (Dol. II) and fracture associated, coarse crystalline dolomite (Dol. III). Stable isotope studies indicate less depleted δ18O values for Dol. I (-6.44 to -3.76‰V-PDB), slightly depleted δ18O values for Do...

Neolithic burials rich in grave goods, referred to as "princesses burials", were excavated in the Kuyavia Lowland, central Poland, Central Europe. The most common elements of grave equipment recorded in these burials were ornaments composed of disc beads made of freshwater bivalve (Unio spp.) shells. Our study was aimed at determining the origin of the shells in question by analysing, for the first time, carbon and oxygen stable isotope compositions (δ 13 C and δ 18 O) of the beads and comparing the results with C and O isotope ratios in modern shells sampled in central Poland. In the research, the isotope values of modern shells were grouped into two data sets representing riverine and lacustrine endmembers. Unio spp. shells sampled from rivers were isotopically lighter (i.e. isotope values were more negative) compared with the shells collected from lakes. The range of δ 13 C and δ 18 O values in the beads was similar to the one observed in modern Unio spp. shells. However, the isotope values differed within and between the archaeological sites studied. In Krusza Zamkowa and Osłonki, two distinct isotopic groups of beads were recognised-riverine and lacustrine-suggesting changes in the shell source in time. The C and O isotope values of beads sampled from Brześć Kujawski indicated the lacustrine origin of the shells used for their production. Also, it was confirmed that shells used to produce one ornament were derived from a single source, and the choice of sources changed in time. Our research revealed that the selection of specific local sources of shells was important for the prehistoric communities under study, and it may be considered the evidence of the existence of a regional exchange network.

This paper is a preliminary investigation into the use of a thermal desorption-gas chromatography-isotope ratio mass spectrometry (TD-GC-IR-MS) method to determine stable carbon isotopic compositions (d 13 C) of low molecular-weight volatile organic compounds (VOCs) in airborne samples (e.g. industrial and car exhaust emissions) as a means of differentiating their sources in the environment. A TD-GC-IR-MS method for obtaining d 13 C of VOCs (benzene, toluene, chlorobenzene, ethylbenzene, m-xylene and propylbenzene) in air samples has been optimised, and is proven to be both reproducible and linear. The d 13 C of the VOC standards was found to be comparable (within analytical error) to that obtained from direct GC-IR-MS analysis. This novel method of VOC analysis is valuable in environmental and forensic investigations.

The stable lead (Pb) isotope ratios and the concentrations of 23 elements, including heavy metals and toxic elements, were measured in the PM 10 airborne particle samples collected at seven monitoring sites in Shanghai, China, to evaluate the current elemental compositions and local airborne Pb isotope ratio characteristics. Some source-related samples, such as cement, coal and oil combustion dust, metallurgic dust, vehicle exhaust particles derived from leaded gasoline and unleaded gasoline, and polluted soils were analyzed for their Pb content and isotope ratio and compared to those observed in PM 10 samples. Airborne Pb concentration ranged from 167 to 854 ng/m 3 in the seven monitored sites with an average of 515 ng/m 3 in Shanghai, indicating that a high concentration of Pb remains in the air after the phasing out of leaded gasoline. Lead isotopic compositions in airborne particles ( 207 Pb/ 206 Pb, 0.860870.0018; 208 Pb/ 206 Pb, 2.10570.005) are clearly distinct from the vehicle exhaust particles ( 207 Pb/ 206 Pb, 0.885470.0075; 208 Pb/ 206 Pb, 2.14570.006), suggesting that the automotive lead is not currently the major component of Pb in the air. By using a binary mixing equation, a source apportionment based on 207 Pb/ 206 Pb ratios, indicates that the contribution from automotive emission to the airborne Pb is around 20%. The Pb isotope ratios obtained in the source-related samples confirmed that the major emission sources are metallurgic dust, coal combustion, and cement. r

Broomcorn millet is one of the most important plants species in pre-history. It was first domesticated in China and subsequently spread across Eurasia becoming a significant staple crop. For a long time, the arrival of millet into Europe was assumed to have taken place in the Neolithic. However, this has recently been challenged, with new direct radiocarbon measurements on reportedly Neolithic charred millet grains in fact dating to the Middle Bronze Age. To aid in understanding the timing of millet’s spread across East-Central Europe in the Bronze Age we present the results of over 120 new paired radiocarbon dates and stable isotope (δ13C and δ15N) measurements on human bone collagen from individuals across 33 archaeological sites in Poland and western Ukraine. In doing so we directly assess millet’s role in the Bronze Age diets. Our results show a clear increase in bone collagen δ13C values from the middle 15th century BC onwards. This increase is rapid across the whole study area...

1. Individual variability in prey preferences can have marked effects on many demographic parameters from individual survival and fecundity to the vital rates of entire populations. A population level response is ultimately determined by individual prey choices; however, the effect of individual dietary choice is often overlooked. 2. We determined prey choice by individual consumers, light-bellied Brent geese Branta bernicla, during the overwintering period. Two hundred and eighty-one individuals were sampled at distinct temporal points over two winters. Stable isotopic ratios of carbon and nitrogen for blood cells and blood plasma, from each sampled individual were measured. Isotopic ratios for potential prey items were also measured. 3. Delta15N and delta13C for blood samples were both significantly different between sample months. Generally we found a decrease in both isotopic ratios during the course of the winter. All potential prey items were also isotopically distinct. Multis...

Mugilidae saltmarsh diet stable isotope analysis stomach content food web European Atlantic coasts a b s t r a c t Mullet populations are abundant in littoral waters throughout the world and play a significant role in organic matter fluxes. Mullets are opportunistic feeders: adults have frequently been shown to feed on primary producers (e.g. fresh or detrital plant material, microphytobenthos) but they may also feed on meiofauna. The population structure and stomach contents of mullets that colonize saltmarsh creeks in Aiguillon Bay (French Atlantic coast) were studied to determine if they use saltmarshes as a feeding ground in spring. Stable isotope analyses were carried out on mullets sampled to assess their diet during their spring migration. The mullet population was primarily composed of young-of-the-year (G0), 1 yearold (G1) of both Liza ramada and Liza aurata species and 3 year-old or older (G3þ) L. ramada individuals. G0 and G3þ population densities increased during the spring period: catch per unit effort (CPUE) increased from 0.22 to 1.49 ind min À1 for the G0 age group; but stomach content analyses revealed that only G1 and G3þ feed in the saltmarsh. Isotopic signatures of G1 (spring: d 13 C: À14.8&, d 15 N: 14.1&) and G3þ mullets (spring: d 13 C: À16.9&, d 15 N: 13.8&) indicate that mullet growth is supported largely by primary consumers, such as benthic meiofauna or small macrofauna. Mullets are thus positioned at a much higher trophic level than true primary consumers.

El Mirón Cave was occupied by humans for over 40,000 years. Evidence of Late Mousterian, Gravettian, Solutrean, Magdalenian, Azilian, Mesolithic, Neolithic, Chalcolithic, Bronze Age and Mediaeval occupations has been found in the cave. Understanding the local environmental conditions during the occupations is crucial for gaining an insight into the lifeways of El Mirón's inhabitants as they relied on the surrounding region and its natural resources for their subsistence. 170 bones of hunted red deer recovered from the cave were sampled for carbon and nitrogen stable isotope analyses with the aim of reconstructing the palaeoenvironment and palaeoclimate during the human occupation. The results show that the surrounding landscape underwent considerable environmental change during the Late Pleistocene and Early to Mid-Holocene. Shifts in δ 13 C values between the Last Glacial Maximum, Heinrich stadial 1, Heinrich event 1, the Late-glacial interstadial and the onset of the Holocene are likely to reflect changes in water availability and temperature. Deer δ 15 N generally increased over time indicating the regeneration of soil biological activity and nitrogen cycling, which was temporarily halted during the Younger Dryas. Comparison of the El Mirón results with those of 300 deer from other regions of Europe shows geographical variations in the timing and magnitude of the variation in δ 13 C and δ 15 N values. This variation tracks local climate (temperature and water availability) and environmental (vegetation and forest development) changes.

This pilot study addresses the analytical characterisation of 26 well‐known bronze objects of the Early and Middle Bronze Age of Central and Northern Europe. Besides swords and axes of the hoards from Apa, Téglás and Hajdúsámson, the investigation includes the famous Sky Disc and its accompanying finds from the Nebra hoard and several full‐hilted swords from Period I in Denmark. In contrast to former publications, the isotopic systematics of lead, tin and copper are the focus of the present investigation. With a combined approach, we try to relate the either typologically closely linked or otherwise related artefacts with chemical and isotopic proxies by identifying mixing scenarios. The results demonstrate that artefacts from different locations are most likely not directly linked, but mixing lines across isotope systems suggest a production of the items from common sources by mixing of bronze batches (e.g. bronze ingots), which were probably disseminated between 1600 and 1500 BC. This helps to correlate objects of different locations with each other and to draw conclusions upon typological and cultural connections. Isotopic and chemical correlations of objects within the individual hoards on the other hand allow reconstructions of metallurgical practices in single workshops, which for example implies recycling of metal scrap.

The largest known colony of Thin-billed prions Pachyptila belcheri, a small burrow-nesting seabird, has been coexisting with introduced mammals for at least 100 years. Three of the introduced mammals at New Island, West Falkland, are potential predators of adults, eggs and chicks, namely ship rats Rattus rattus, house mice Mus musculus and feral cats Felis catus. To study their trophic interrelationships and evaluate the importance of marine food in their diets, we used a stable isotope approach, comparing δ13C and δ15N of tissue and stomach contents of trapped rats and mice, and feces of cats, all collected during the nestling period of Thin-billed prions. We found that rats in three of four areas had a diet of partly marine and terrestrial origin while one area, the Rookery tussac, was distinguished by mainly terrestrial food. We further analyzed individual consistency of diet in ship rats using stomach contents and feces (representing the last few meals) and liver and muscle tiss...