Back to the bases: Building a terrestrial water δ18O baseline for archaeological studies in North Patagonia (Argentina)

Archaeology has been using stable oxygen as an isotopic tracer linked with water consumption for decades, and it has been demonstrated to be a powerful tool to assess paleomobility in bioarchaeology. Central-eastern North Patagonia (Argentina) is an especially appropriate region to apply it since it presents a high density of huntergatherer burials, it was a nodal zone criss-crossed by an extensive network of important routes, and it is characterized by a high environmental fragmentation due to the scarcity of fresh water sources. The aim of this paper is to build an empirical stable oxygen isotope baseline of terrestrial surface waters to assess the potentiality of tracing past human movement. We analyzed 46 water samples from 13 locations with permanent sources (rivers, springs, streams), compared it with predictions of precipitation and evaluated it considering seasonal variation, altitude and distance from the coast. Our results show that different post-precipitation processes change the isotopic signal from the sources with respect to the local precipitation, and highlight the relevance of analyzing terrestrial water sources. According to their oxygen isotope values we defined five hydrologic zones: Colorado River, Negro River, Closed Basins and Plains, Eastern and Western Somuncurá Foothills. Their identification shows the potential to address past human movement using stable oxygen water baselines in central-eastern North Patagonia

Back to the bases: Building a terrestrial water δ18O baseline for archaeological studies in North Patagonia (Argentina)

Archaeology has been using stable oxygen as an isotopic tracer linked with water consumption for decades, and it has been demonstrated to be a powerful tool to assess paleomobility in bioarchaeology. Central-eastern North Patagonia (Argentina) is an especially appropriate region to apply it since it presents a high density of huntergatherer burials, it was a nodal zone criss-crossed by an extensive network of important routes, and it is characterized by a high environmental fragmentation due to the scarcity of fresh water sources. The aim of this paper is to build an empirical stable oxygen isotope baseline of terrestrial surface waters to assess the potentiality of tracing past human movement. We analyzed 46 water samples from 13 locations with permanent sources (rivers, springs, streams), compared it with predictions of precipitation and evaluated it considering seasonal variation, altitude and distance from the coast. Our results show that different post-precipitation processes change the isotopic signal from the sources with respect to the local precipitation, and highlight the relevance of analyzing terrestrial water sources. According to their oxygen isotope values we defined five hydrologic zones: Colorado River, Negro River, Closed Basins and Plains, Eastern and Western Somuncurá Foothills. Their identification shows the potential to address past human movement using stable oxygen water baselines in central-eastern North Patagonia.Facultad de Ciencias Naturales y Muse

Dietary transition in native populations of Northern Tierra del Fuego during the Salesian missionary period: an isotopic approach

La misión salesiana La Candelaria funcionó de 1893 a 1928 en el norte de Tierra del Fuego, aunque su cementerio fue usado hasta 1948. Las fuentes históricas sugieren que los nativos que la habitaron sufrieron fuertes cambios en su dieta con respecto a los cazadoresrecolectores de la zona. El cambio estaría caracterizado por un gran incremento en el consumo de harina, arroz, papas y azúcar, que remplazan al guanaco como fuente principal de alimento. Nuestro objetivo es evaluar la transición alimentaria de los habitantes de la misión a través del análisis de isótopos estables de carbono y nitrógeno sobre huesos (colágeno, apatita) y dientes (dentina, esmalte) de 23 individuos exhumados del cementerio. Los valores de δ15N en colágeno (δ15Nc) y de δ13C tanto en colágeno (δ13Cc) como en apatita (δ13Ca) de individuos del cementerio resultaron más bajos que los valores publicados para la región para períodos pre-contacto. Dentro del cementerio, los valores de δ15Nc y de δ13Ca resultaron más bajos que los de δ15Nd (dentina) y de δ13Ce (esmalte), pero no hubo diferencias entre valores de δ13Cc y δ13Cd. Los valores de δ15Nd y δ13Cd resultaron significativamente más bajos que los valores de colágeno para períodos pre-contacto. Estos resultados son consistentes con la hipótesis planteada por las fuentes históricas y sugieren un desequilibrio en la dieta, con una mayor proporción de carbohidratos y una menor proporción de proteínas animales en los habitantes de la misión con relación a los cazadores-recolectores de Tierra del Fuego de períodos pre-contacto.The Salesian mission La Candelaria was run from 1893 to 1928 in the north of Tierra del Fuego, but its cemetery was in use until 1948. Historical sources suggest that the natives living there underwent marked dietary changes with respect to the hunter-gatherers of the area. The change can be characterized by a large increase in the consumption of flour, rice, potatoes, and sugar, in replacement of guanaco, as their main food source. Our objective is to evaluate the dietary transition experienced by the inhabitants of the mission through the analysis of stable isotopes of carbon and nitrogen on bones (collagen, apatite) and teeth (dentin, enamel) of 23 individuals exhumed from the cemetery. The δ15N values in collagen (δ15Nc), and δ13C values both in collagen (δ13Cc) and in apatite (δ13Ca) of samples from the cemetery were lower than the values published for the region in pre-contact periods. Within the cemetery, the δ15Nc, δ13Cc and δ13Ca values were lower than those of δ15Nd (dentin) and δ13Ce (enamel), but there were no differences between δ13Cc and δ13Cd values. The δ15Nd and δ13Cd values were significantly lower than the isotope values of collagen for pre-contact periods. The results are consistent with the hypothesis raised by historical sources and suggest an imbalance in the diet, with a higher proportion of carbohydrates and a lower proportion of animal proteins in the inhabitants of the mission in comparison with the hunter-gatherers of Tierra del Fuego of pre-contact periods.Asociación de Antropología Biológica de la República Argentin

Dietary transition in native populations of Northern Tierra del Fuego during the Salesian missionary period: an isotopic approach

La misión salesiana La Candelaria funcionó de 1893 a 1928 en el norte de Tierra del Fuego, aunque su cementerio fue usado hasta 1948. Las fuentes históricas sugieren que los nativos que la habitaron sufrieron fuertes cambios en su dieta con respecto a los cazadoresrecolectores de la zona. El cambio estaría caracterizado por un gran incremento en el consumo de harina, arroz, papas y azúcar, que remplazan al guanaco como fuente principal de alimento. Nuestro objetivo es evaluar la transición alimentaria de los habitantes de la misión a través del análisis de isótopos estables de carbono y nitrógeno sobre huesos (colágeno, apatita) y dientes (dentina, esmalte) de 23 individuos exhumados del cementerio. Los valores de δ15N en colágeno (δ15Nc) y de δ13C tanto en colágeno (δ13Cc) como en apatita (δ13Ca) de individuos del cementerio resultaron más bajos que los valores publicados para la región para períodos pre-contacto. Dentro del cementerio, los valores de δ15Nc y de δ13Ca resultaron más bajos que los de δ15Nd (dentina) y de δ13Ce (esmalte), pero no hubo diferencias entre valores de δ13Cc y δ13Cd. Los valores de δ15Nd y δ13Cd resultaron significativamente más bajos que los valores de colágeno para períodos pre-contacto. Estos resultados son consistentes con la hipótesis planteada por las fuentes históricas y sugieren un desequilibrio en la dieta, con una mayor proporción de carbohidratos y una menor proporción de proteínas animales en los habitantes de la misión con relación a los cazadores-recolectores de Tierra del Fuego de períodos pre-contacto.The Salesian mission La Candelaria was run from 1893 to 1928 in the north of Tierra del Fuego, but its cemetery was in use until 1948. Historical sources suggest that the natives living there underwent marked dietary changes with respect to the hunter-gatherers of the area. The change can be characterized by a large increase in the consumption of flour, rice, potatoes, and sugar, in replacement of guanaco, as their main food source. Our objective is to evaluate the dietary transition experienced by the inhabitants of the mission through the analysis of stable isotopes of carbon and nitrogen on bones (collagen, apatite) and teeth (dentin, enamel) of 23 individuals exhumed from the cemetery. The δ15N values in collagen (δ15Nc), and δ13C values both in collagen (δ13Cc) and in apatite (δ13Ca) of samples from the cemetery were lower than the values published for the region in pre-contact periods. Within the cemetery, the δ15Nc, δ13Cc and δ13Ca values were lower than those of δ15Nd (dentin) and δ13Ce (enamel), but there were no differences between δ13Cc and δ13Cd values. The δ15Nd and δ13Cd values were significantly lower than the isotope values of collagen for pre-contact periods. The results are consistent with the hypothesis raised by historical sources and suggest an imbalance in the diet, with a higher proportion of carbohydrates and a lower proportion of animal proteins in the inhabitants of the mission in comparison with the hunter-gatherers of Tierra del Fuego of pre-contact periods.Asociación de Antropología Biológica de la República Argentin

Decadal shift in foraging strategy of a migratory southern ocean predator

Rapid anthropogenic environmental change is expected to impact a host of ecological parameters in Southern Ocean ecosystems. Of critical concern are the consequences of these changes on the range of species that show fidelity to migratory destinations, as philopatry is hypothesized to help or hinder adaptation to climate change depending on the circumstances. Many baleen whales show philopatry to feeding grounds and are also capital breeders that meet migratory and reproductive costs through seasonal energy intake. Southern right whales (Eubalaena australis, SRWs) are capital breeders that have a strong relationship between reproductive output and foraging success. The population dynamics of South Africa's population of SRWs are characterized by two distinct periods: the 1990s, a period of high calving rates; and the late 2010s, a period associated with lowered calving rates. Here we use analyses of stable carbon (δ13C) and nitrogen (δ15N) isotope values from SRW biopsy samples (n = 122) collected during these two distinct periods to investigate foraging ecology of the South African population of SRWs over a time period coincident with the demographic shift. We show that South African SRWs underwent a dramatic northward shift, and diversification, in foraging strategy from 1990s to 2010s. Bayesian mixing model results suggest that during the 1990s, South African SRWs foraged on prey isotopically similar to South Georgia/Islas Georgias del Sur krill. In contrast, in the 2010s, South African SRWs foraged on prey isotopically consistent with the waters of the Subtropical Convergence, Polar Front and Marion Island. We hypothesize that this shift represents a response to changes in preferred habitat or prey, for example, the decrease in abundance and southward range contraction of Antarctic krill. By linking reproductive decline to changing foraging strategies for the first time in SRWs, we show that altering foraging strategies may not be sufficient to adapt to a changing ocean

Genetic diversity and connectivity of southern right whales (Eubalaena australis) found in the Brazil and Chile-Peru wintering grounds and the South Georgia (Islas Georgias del Sur) feeding ground

As species recover from exploitation, continued assessments of connectivity and population structure are warranted to provide information for conservation and management. This is particularly true in species with high dispersal capacity, such as migratory whales, where patterns of connectivity could change rapidly. Here we build on a previous long-term, large-scale collaboration on southern right whales (Eubalaena australis) to combine new (nnew) and published (npub) mitochondrial (mtDNA) and microsatellite genetic data from all major wintering grounds and, uniquely, the South Georgia (Islas Georgias del Sur: SG) feeding grounds. Specifically, we include data from Argentina (npub mtDNA/microsatellite=208/46), Brazil (nnew mtDNA/microsatellite=50/50), South Africa (nnew mtDNA/microsatellite=66/77, npub mtDNA/microsatellite=350/47), Chile-Peru (nnew mtDNA/microsatellite=1/1), the Indo-Pacific (npub mtDNA/microsatellite=769/126), and SG (npub mtDNA/microsatellite=8/0, nnew mtDNA/microsatellite=3/11) to investigate the position of previously unstudied habitats in the migratory network: Brazil, SG and Chile-Peru. These new genetic data show connectivity between Brazil and Argentina, exemplified by weak genetic differentiation and the movement of one genetically identified individual between the South American grounds. The single sample from Chile-Peru had a mtDNA haplotype previously only observed in the Indo-Pacific and had a nuclear genotype that appeared admixed between the Indo-Pacific and South Atlantic, based on genetic clustering and assignment algorithms. The SG samples were clearly South Atlantic, and were more similar to the South American than the South African wintering grounds. This study highlights how international collaborations are critical to provide context for emerging or recovering regions, like the SG feeding ground, as well as those that remain critically endangered, such as Chile-Peru

Patterns of local and nonlocal water resource use across the western U.S. determined via stable isotope intercomparisons

In the western U.S., the mismatch between public water demands and natural water availability necessitates large interbasin transfers of water as well as groundwater mining of fossil aquifers. Here we identify probable situations of nonlocal water use in both space and time based on isotopic comparisons between tap waters and potential water resources within hydrologic basins. Our approach, which considers evaporative enrichment of heavy isotopes during storage and distribution, is used to determine the likelihood of local origin for 612 tap water samples collected from across the western U.S. We find that 64% of samples are isotopically distinct from precipitation falling within the local hydrologic basin, a proxy for groundwater with modern recharge, and 31% of samples are isotopically distinct from estimated surface water found within the local basin. Those samples inconsistent with local water sources, which we suggest are likely derived from water imported from other basins or extracted from fossil aquifers, are primarily clustered in southern California, the San Francisco Bay area, and central Arizona. Our isotope-based estimates of nonlocal water use are correlated with both hydrogeomorphic and socioeconomic properties of basins, suggesting that these factors exert a predictable influence on the likelihood that nonlocal waters are used to supply tap water. We use these basin properties to develop a regional model of nonlocal water resource use that predicts (r2 = 0.64) isotopically inferred patterns and allows assessment of total interbasin transfer and/or fossil aquifer extraction volumes across the western U.S.Fil: Good, Stephen P.. University of Utah; Estados UnidosFil: Kennedy, Casey D.. United States Department Of Agriculture. Agriculture Research Service; Estados UnidosFil: Stalker Jeremy C.. Jacksonville University; Estados UnidosFil: Chesson, Lesley A.. IsoForensics; Estados UnidosFil: Valenzuela, Luciano Oscar. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Sociales. Departamento de Arqueología. Laboratorio de Ecología Evolutiva Humana (Sede Quequén); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. University of Utah; Estados UnidosFil: Beasley, Melanie M.. University of California at San Diego; Estados UnidosFil: Ehleringer, James R. University of Utah; Estados UnidosFil: Bowen, Gabriel J.. University of Utah; Estados Unido

Aberrant Water Homeostasis Detected by Stable Isotope Analysis

While isotopes are frequently used as tracers in investigations of disease physiology (i.e., 14C labeled glucose), few studies have examined the impact that disease, and disease-related alterations in metabolism, may have on stable isotope ratios at natural abundance levels. The isotopic composition of body water is heavily influenced by water metabolism and dietary patterns and may provide a platform for disease detection. By utilizing a model of streptozotocin (STZ)-induced diabetes as an index case of aberrant water homeostasis, we demonstrate that untreated diabetes mellitus results in distinct combinations, or signatures, of the hydrogen (δ2H) and oxygen (δ18O) isotope ratios in body water. Additionally, we show that the δ2H and δ18O values of body water are correlated with increased water flux, suggesting altered blood osmolality, due to hyperglycemia, as the mechanism behind this correlation. Further, we present a mathematical model describing the impact of water flux on the isotopic composition of body water and compare model predicted values with actual values. These data highlight the importance of factors such as water flux and energy expenditure on predictive models of body water and additionally provide a framework for using naturally occurring stable isotope ratios to monitor diseases that impact water homeostasis

Dietary Heterogeneity among Western Industrialized Countries Reflected in the Stable Isotope Ratios of Human Hair

Although the globalization of food production is often assumed to result in a homogenization of consumption patterns with a convergence towards a Western style diet, the resources used to make global food products may still be locally produced (glocalization). Stable isotope ratios of human hair can quantify the extent to which residents of industrialized nations have converged on a standardized diet or whether there is persistent heterogeneity and glocalization among countries as a result of different dietary patterns and the use of local food products. Here we report isotopic differences among carbon, nitrogen and sulfur isotope ratios of human hair collected in thirteen Western European countries and in the USA. European hair samples had significantly lower δ13C values (−22.7 to −18.3‰), and significantly higher δ15N (7.8 to 10.3‰) and δ34S (4.8 to 8.3‰) values than samples from the USA (δ13C: −21.9 to −15.0‰, δ15N: 6.7 to 9.9‰, δ34S: −1.2 to 9.9‰). Within Europe, we detected differences in hair δ13C and δ34S values among countries and covariation of isotope ratios with latitude and longitude. This geographic structuring of isotopic data suggests heterogeneity in the food resources used by citizens of industrialized nations and supports the presence of different dietary patterns within Western Europe despite globalization trends. Here we showed the potential of stable isotope analysis as a population-wide tool for dietary screening, particularly as a complement of dietary surveys, that can provide additional information on assimilated macronutrients and independent verification of data obtained by those self-reporting instruments

Recent results on heavy-ion induced reactions of interest for neutrinoless double beta decay at INFN-LNS

Abstract. The possibility to use a special class of heavy-ion induced direct reactions, such as double charge exchange reactions, is discussed in view of their application to extract information that may be helpful to determinate the nuclear matrix elements entering in the expression of neutrinoless double beta decay halflife. The methodology of the experimental campaign presently running at INFN - Laboratori Nazionali del Sud is reported and the experimental challenges characterizing such activity are describe