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The Holocene paleoclimate of the Caucasus region is rather complex and not yet well understood: while existing studies are mainly based on pollen records from high-altitude and humid lowland regions, no records are available from the semi-humid to semi-arid south-eastern Caucasian lowlands. Therefore, this study investigated compound-specific δ2H and δ13C isotopes of leaf wax biomarkers from Holocene floodplain soils in eastern Georgia. Our results show that the leaf wax δ2H signal from the paleosols mostly reflects changes in the moisture source and its isotopic composition. Depleted δ2H values before ~8?cal ka bp change towards enriched values after ~5?cal ka bp and become again depleted after ~1.6?cal ka bp. This trend could be caused by Holocene changes of the isotopic compositions of the Black and eastern Mediterranean Sea, and/or by varying contribution of both moisture sources linked with the North Atlantic Oscillation. The leaf wax δ13C signal from the paleosols directly indicates varying local water availability and drought stress. Depleted δ13C values before ~8 and after ~5?cal ka bp indicate wetter local conditions with higher water availability, whereas more enriched values during the middle Holocene (~8 until at least 5?cal ka bp) indicate drier conditions with increased drought stress. Introduction Materials and methods - Study area and climate setting - Studied section - Analytical procedure Results Discussion - The δ2H signal - The δ13C signal Conclusions

Objectives: Colonial period New Zealand was lauded as a land of plenty, where colonists could improve their station in life and secure a future for their families. Our understanding of colonial experience, however, is often shaped by historical records which communicate a state‐sponsored version of history. This study aims to reconstruct the lives of settlers using isotopic evidence from the colonial skeletons themselves. Materials and methods: We use skeletal remains from recently excavated colonial sites in Otago (South Island, New Zealand) to illustrate the information that can be gleaned from the isotopic analysis of individuals. We use 87Sr/86Sr to identify European settlers, and δ13C and δ15N from collagen and hair keratin, as well as dental enamel carbonate δ13C to trace dietary change over their life‐courses. Results: Strontium isotope analysis shows that all adults in our sample are non‐local. Dietary isotopes show that while most individuals had relatively consistent childhood diet, one individual with more rural origins likely had seasonal use of resources during childhood. While some members of the population seem to have increased their meat intake in the new colony most do not have clear evidence for this. Discussion: We show the diversity of human experience in first‐generation New Zealanders both prior to emigration and in the new colony. Despite colonial propaganda claiming that circumstances in New Zealand were improved for all settlers, we have little evidence for this, aside from among individuals of potentially high status.

The Mediterranean Peninsula increasingly suffers from droughts and aridity, the first consequences of global climate change in that region. Precise scenarios for the region's future climate predictions require knowledge about the processes of past climate changes, but information about the Western Mediterranean climate and its history is controversial. For this study, we applied compound-specific δ13C and δ2H analyses on long-chain n-alkanes in the ~8 m El Paraiso loess-paleosoil sequence (LPS), Central Spain, to investigate climate and environmental changes during the Late Quaternary. The δ13C values are most enriched during marine isotope stage (MIS) 3, indicating more arid conditions, while lower values during MIS 4 and 2 are interpreted to document more humid conditions. Low values are also recorded for the Holocene colluvium, which can at least partly be explained with higher concentrations in atmospheric CO2. The δ2H values are mostly enriched during the last glacial compared to the Holocene. We suggest that this is mainly controlled by isotopic effects related to the moisture source, yet other possible effects like evapotranspirative enrichment and changes in atmospheric circulation patterns shouldn't be ruled out. Our results corroborate previous findings based on leaf wax patterns, geomorphological records, and climate models. They all indicate relatively humid conditions during MIS 2 compared to more arid phases during MIS 3.

The combined Rhone and Aare Glaciers presumably reached their last glacial maximum (LGM) extent on the Swiss Plateau prior to 24 ka. Two well-preserved, less extensive moraine stades, the Gurten and Bern Stade, document the last deglaciation of the Aare Valley, yet age constraints are very scarce. In order to establish a more robust chronology for the glacial/deglacial history of the Aare Valley, we applied 10Be surface exposure dating on eleven boulders from the Gurten and Bern Stade. Several exposure ages are of Holocene age and likely document post-depositional processes, including boulder toppling and quarrying. The remaining exposure ages, however yield oldest ages of 20.7 ± 2.2 ka for the Gurten Stade and 19.0 ± 2.0 ka for the Bern Stade. Our results are in good agreement with published chronologies from other sites in the Alps. Fil: Wüthrich, Lorenz. University of Bern; Suiza Fil: Garcia Morabito, Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Diversidad Cultural y Procesos de Cambio. Universidad Nacional de Río Negro. Instituto de Investigaciones en Diversidad Cultural y Procesos de Cambio; Argentina. University of Bern; Suiza Fil: Zech, Jana. University of Bern; Suiza Fil: Trauerstein, Mareike. University of Bern; Suiza Fil: Veit, Heinz. University of Bern; Suiza Fil: Gnägi, Christian. University of Bern; Suiza Fil: Merchel, Silke. Helmholtz-zentrum, Dresden-rossendorf, Deutschland; Alemania Fil: Scharf, Andreas. Helmholtz-Zentrum; Alemania Fil: Rugel, Georg. Helmholtz-Zentrum; Alemania Fil: Christl, Marcus. Eidgenössische Technische Hochschule Zürich; Suiza Fil: Zech, Roland. University of Bern; Suiza

Elemental analysis of biogeochemical archives is an established technique used to study climate in a range of applications, including ocean circulation, glacial/interglacial climates, and anthropogenic climate change. Data from mollusc archives are especially important because of their global abundance and sub-annual resolution. Despite this potential, they are underrepresented among palaeoclimate studies, due to enigmatic physiological influences skewing the elemental record. Understanding the patterns behind these influences will improve data interpretation and lead to the development of new climate proxies. Here, we show for the first time that extensive spatial mapping of multiple mollusc specimens using Laser Induced Breakdown Spectroscopy (LIBS) across a wider region can resolve enigmatic patterns within the elemental record caused by physiological influences. 2D elemental (Mg/Ca) maps of whole limpet shells (Patella caerulea) from across the Mediterranean revealed patterns of variability within individual mollusc records as well as within isochronous parts of specimens. By registering and quantifying these patterns, we established previously uninterpretable correlations with temperature (R2 > 0.8, p < 0.01). This outcome redefines the possibilities of accessing sub-annual climate proxies and presents the means to assess annual temperature ranges using oxygen isotope analysis requiring only 2 samples per shell.

Elemental analysis of biogeochemical archives is an established technique used to study climate in a range of applications, including ocean circulation, glacial/interglacial climates, and anthropogenic climate change. Data from mollusc archives are especially important because of their global abundance and sub-annual resolution. Despite this potential, they are underrepresented among palaeoclimate studies, due to enigmatic physiological influences skewing the elemental record. Understanding the patterns behind these influences will improve data interpretation and lead to the development of new climate proxies. Here, we show for the first time that extensive spatial mapping of multiple mollusc specimens using Laser Induced Breakdown Spectroscopy (LIBS) across a wider region can resolve enigmatic patterns within the elemental record caused by physiological influences. 2D elemental (Mg/Ca) maps of whole limpet shells (Patella caerulea) from across the Mediterranean revealed patterns of variability within individual mollusc records as well as within isochronous parts of specimens. By registering and quantifying these patterns, we established previously uninterpretable correlations with temperature (R2 > 0.8, p < 0.01). This outcome redefines the possibilities of accessing sub-annual climate proxies and presents the means to assess annual temperature ranges using oxygen isotope analysis requiring only 2 samples per shell.

In the mid-late nineteenth century thousands flocked to the newly-established British colony of New Zealand in the hope of improving their fortunes and forging a better life. While historical records give us an overview of where these people came from, in many cases the individual stories of the people who make up early colonial society have been lost. In this study we use isotopic analysis (87Sr/86Sr, lead isotopes and δ18O) and ancient DNA (aDNA) to look at three cemetery populations from early colonial Otago (South Island, New Zealand). One from an organised agricultural settlement, the other two from the Otago goldfields – associated with the early goldrush, and the later influx of Chinese miners to the area. Overall, we assessed individual origins of the people in these cemetery samples, with the aim of better understanding who came to colonial Otago, and how this relates to modern perceptions of Pākehā (non-Māori) identity in New Zealand. Our findings show that many of the individuals presumed to be Chinese from material culture are isotopically distinct, and have Asian derived maternal ancestry, laying the foundation for future work on unidentified historic remains. However, some individuals are associated with seemingly conflicting isotopic and DNA data which hints at the complexity of individual construction of identity in a colonial context.

Stable oxygen isotope ratios of mollusc shells (δ18Oshell) offer the possibility to reconstruct coastal resource exploitation patterns and changes in the oceanographic conditions of direct relevance to past human populations. This method relies on the fact that shell carbonate is deposited by molluscs in equilibrium with their surrounding environment and actualistic investigation of modern specimens is needed to ensure that selected species can be used as accurate palaeoclimate indicators. The limpet Patella depressa Pennant, 1777 is one of the most common mollusc species found in Holocene archaeological assemblages along the Atlantic coast of Europe. However, this taxon has not, to date, been tested as a seawater palaeothermometer. Here, we explore the ability of P. depressa to be used as an environmental recorder in this littoral region, specifically in northern Iberia where we obtained live-collected specimens throughout the year. We undertook sclerochronological investigations combining observations of incremental shell growth patterns with δ18Oshell values. Carbonate samples were taken on (i) the ventral margins of shells collected alive year-round in order to test for isotopic equilibrium and (ii) along the axis of maximum shell growth of four modern specimens to decipher the shell growth pattern of this species. Isotopic data showed that calcium carbonate is precipitated in predictable isotopic disequilibrium with the ambient seawater (R2 = 0.95; p < 0.0001), reporting a consistent offset of +1.08‰. Some periods of growth cessation were observed in the shells when thermal tolerances were exceeded in winter and occasionally in summer. Nevertheless, estimated seawater temperatures from modern shell δ18Oshell values agreed closely with instrumentally measured temperatures (R2 = 0.88–0.93; p < 0.0001) and correctly reflected seasonal temperature patterns. As a result, multi-proxy analysis of P. depressa shells can provide a high-resolution palaeothermometer with significant implications for future palaeoclimate and archaeological studies along the Atlantic coast of Europe.

The transition from Late Antiquity to the Medieval period is considered one of the greatest periods of social, political, and economic upheaval in Europe, and has left its mark on the historical consciousness of people in this part of the world. Nevertheless, there remains considerable debate as to the degree to which the diets and economic status of different sections of society were impacted by this transition, with these so-called ‘Dark Ages’ often being uniformly considered as static and impoverished, particularly for populations along the Mediterranean rim. Such questions are especially important in central Italy, with its position at the former core of the Roman Empire leaving it most vulnerable to the major social and political shifts of the first millennium AD. However, direct insights into the diets of individuals in this region, across this key period, have been scarce, particularly in diachronic perspective. Here, we apply stable carbon (δ13C) and nitrogen (δ15N) analysis to bone collagen (n = 76), and stable carbon (δ13C) and oxygen (δ18O) isotope analysis to tooth enamel (n = 34), to human, and associated faunal, individuals dated to Late Antiquity (3rd–5th centuries AD) and the Medieval period (mid 6th–mid 13th centuries AD) in Tuscany. δ13C measurements of both tooth enamel bioapatite and bone collagen suggest that a predominantly C3 diet during Late Antiquity was gradually supplemented by increased C4 consumption during the Medieval period. We interpret this as a shift from an agricultural focus on wheat following the Roman agrarian tradition towards the inclusion of millet as a reliable fallback food. We argue that this was part of a growing local and regional resilience amongst communities in the Medieval period, with more diverse agricultural systems and cultural preferences following a transition from the Roman classical civilization toward a Germanic tradition whose economy was based on the diverse cultivation of “minor crops” and close integration of pastoral husbandry livestock.

Summary Modern humans have inhabited the Lake Baikal region since the Upper Paleolithic, though the precise history of its peoples over this long time span is still largely unknown. Here, we report genome-wide data from 19 Upper Paleolithic to Early Bronze Age individuals from this Siberian region. An Upper Paleolithic genome shows a direct link with the First Americans by sharing the admixed ancestry that gave rise to all non-Arctic Native Americans. We also demonstrate the formation of Early Neolithic and Bronze Age Baikal populations as the result of prolonged admixture throughout the eighth to sixth millennium BP. Moreover, we detect genetic interactions with western Eurasian steppe populations and reconstruct Yersinia pestis genomes from two Early Bronze Age individuals without western Eurasian ancestry. Overall, our study demonstrates the most deeply divergent connection between Upper Paleolithic Siberians and the First Americans and reveals human and pathogen mobility across Eurasia during the Bronze Age.

The ecological adaptations that stimulated the dispersal and technological strategies of our species during the Late Pleistocene remain hotly disputed, with some influential theories focusing on grassland biomes or marine resources as key drivers behind the rapid expansion and material culture innovations of Homo sapiens within and beyond Africa. Here, we present novel chronologically resolved, zooarchaeological taxonomic and taphonomic analysis, and stable isotope analysis of human and faunal tooth enamel, from the site of Panga ya Saidi (c. 78–0.4 ka), Kenya. Zooarchaeological data provide rare insights into the fauna associated with, and utilized by, Late Pleistocene-Holocene human populations in tropical coastal eastern Africa. Combined zooarchaeological and faunal stable isotope data provide some of the only dated, ‘on-site’ archives of palaeoenvironments beyond the arid interior of eastern Africa for this time period, while stable isotope analysis of humans provides direct snapshots of the dietary reliance of foragers at the site. Results demonstrate that humans consistently utilized tropical forest and grassland biomes throughout the period of site occupation, through a transition from Middle Stone Age to Later Stone Age technological industries and the arrival of agriculture in the region. By contrast, while coastal resources were obtained for use in symbolic material culture, there is limited evidence for consumption of marine resources until the Holocene. We argue that the ecotonal or heterogeneous environments of coastal eastern Africa may have represented an important refugium for populations during the increasing climatic variability of the Late Pleistocene and Holocene, and that tropical environments were one of a diverse series of ecosystems exploited by H. sapiens in Africa at the dawn of global migrations.

It is difficult to untangle the mixed influences of high- and low-latitude climate forcing in the eastern equatorial Pacific (EEP). Here we test the hypothesis that the Southern Ocean drove change in the EEP via subsurface intermediate waters during the last deglaciation. We use the δ18O signature of benthic foraminifera to reconstruct water density changes during the last 25 kyr at three intermediate water depths (370 m, 600 m, and 1000 m) in the EEP. Carbonate δ18O records a combined signature of temperature and salinity and is therefore more closely related to density than temperature or salinity alone. We find that benthic foraminiferal δ18O values decreased first in the subsurface, simultaneously with rising temperatures over Antarctica, and propagated up to the surface within ~3 kyr. The early subsurface response initiated a rapid decrease in density stratification over the upper water column as indicated by reduced δ18O gradients between surface and intermediate depths. Stratification of the upper water column remained low through the termination, with stratification minima reached during Heinrich Stadial 1 and the Younger Dryas (YD), synchronous with the two-part deglacial rise in atmospheric CO2. Centennial-scale shifts toward heavier δ18O signatures at 370 and 600 m during the YD indicate short-lived shifts in the Subantarctic Mode Water/Antarctic Intermediate Water boundary to shallower intermediate depths. We suggest that decreased density gradients during the deglaciation accelerated vertical mixing across the EEP, and potentially the entire South Pacific subtropical gyre, which enhanced CO2 delivery from depth to the surface ocean and atmosphere.

Although glacial landscapes have previously been used for the reconstruction of late Quaternary glaciations in the Central Andes, only few data exist for the Eastern Cordillera in Bolivia. Here, we present results from detailed morphostratigraphic mapping and new data of surface exposure dating (SED), optically stimulated luminescence (OSL), and radiocarbon dating (14C) from the Huara Loma Valley, Cordillera de Cochabamba (Bolivia). Discrepancies between individual dating methods could be addressed within the context of a solid geomorphic framework. We identified two major glaciations. The older is not well constrained by the available data, whereas the younger glaciation is subdivided into at least four major glacial stages. Regarding the latter, a first advance dated to ~ 29–25 ka occurred roughly contemporaneous with the onset of the global last glacial maximum (LGM) and was followed by a less extensive (re-)advance around 20–18 ka. The local last glacial maximum (LLGM) in the Huara Loma Valley took place during the humid lateglacial ~17–16 ka, followed by several smaller readvances until ~10–11 ka, and complete deglaciation at the end of the Early Holocene.

The response of the tropics to North Atlantic cold events, such as Heinrich Event I (H-I, ∼ 17–15 ka) and the Younger Dryas (YD, 12.7–11.5 ka), is still one of the most tantalizing, yet unresolved issues in paleoclimatology. The advent of surface exposure dating has therefore instigated the establishment of glacial chronologies in the tropical Andes to investigate potential climate teleconnections. Here, we present new exposure ages from the Cordillera Cochabamba (17°17′S), Bolivia, that reveal glacial advances during H-I and YD, as well as during the Early Holocene. Our chronology correlates well with cold sea surface temperatures in the eastern tropical Pacific, which indicates that La Nina-like conditions, i.e. forcings intrinsic to the tropics, played a key role for moisture advection and glaciation in the tropical Andes.

We present 35 10 Be surface exposure ages from quartzite moraine boulders at Tres Lagunas in the Sierra de Santa Victoria, NW Argentina. Additionally, an ~ 8 m sediment core from a glacial lake was investigated to provide independent radiocarbon age control. The oldest and most extensive glaciation occurred ≥ 116.3 ka and likely coincides with the lake transgression phase Ouki on the Altiplano. Maximum glaciation in phase with the global Last Glacial Maximum (LGM) is dated to 22–25 ka and documents a glacial mass-balance response to substantially lower temperatures and minor precipitation increase in phase with the Sajsi lake transgression phase. After initial deglaciation and formation of a small paleolake at Tres Lagunas, a glacial readvance is documented by an outwash diamict in the sediment core and radiocarbon dated to 19–17 ka, as well as by a moraine surface exposure dated to ~ 17 ka. The most prominent moraine was deposited at ≥ 14.5 ka coinciding with the lake transgression phase Tauca on the Altiplano. This Late Glacial advance reflects the massive intensification of the South American Summer Monsoon (SASM) in response to northern hemispheric cooling during Heinrich I and the resultant southward shift of the intertropical convergence zone (ITCZ) and La Nina like conditions in the eastern equatorial Pacific. Rapid deglaciation started after ~ 14.5 ka, interrupted only by minor glacial still stands at ~ 13.8 ± 1.5 ka and 12.0 ± 1.5 ka, the latter one correlating with the Coipasa transgression phase on the Altiplano and the Younger Dryas.