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Oral Histories: a simple method of assigning chronological age to isotopic values from human dentine collagenBeaumont, Julia, Montgomery, Janet 07 1900 (has links)
Yes / Background: stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) in bone and dentine collagen have been used for over 30 years to estimate palaeodiet, subsistence strategy, breastfeeding duration and migration within burial populations. Recent developments in dentine microsampling allow improved temporal resolution for dietary patterns.
Aim: We propose a simple method which could be applied to human teeth to estimate chronological age represented by dentine microsamples in the direction of tooth growth, allowing comparison of dietary patterns between individuals and populations. The method is tested using profiles from permanent and deciduous teeth of two individuals.
Subjects and methods: using a diagrammatic representation of dentine development by approximate age for each human tooth (based on the Queen Mary University of London Atlas) (AlQahtani et al., 2010), we estimate the age represented by each dentine section. Two case studies are shown: comparison of M1 and M2 from a 19th century individual from London, England, and identification of an unknown tooth from an Iron Age female adult from Scotland.
Results and conclusions: The isotopic profiles demonstrate that variations in consecutively-forming teeth can be aligned using this method to extend the dietary history of an individual, or identify an unknown tooth by matching the profiles.
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Identifying cohorts using isotope mass spectrometry: the potential of temporal resolution and dietary profilesBeaumont, Julia, Bekvalac, J., Harris, Sam, Batt, Catherine M. 14 February 2021 (has links)
Yes / Archaeological skeletal material from most sites represents a cross-sectional, opportunistic sample of the burials. These are influenced by the proportion and area of the site which is excavated, the taphonomic conditions and survival of tissues. This may not be representative of the population, and in an attritional cemetery may represent a long period of use, during which humans will have differing life-courses. Here we describe a commingled skeletal assemblage, the only human remains recovered from the historically significant medieval site of St Stephen’s Chapel, Palace of Westminster, London. Using carbon (δ13C) and nitrogen (δ15N) stable isotope ratios of bulk bone collagen and incremental dentine to investigate dietary life histories from 5 individuals, we combine the evidence with radiocarbon dating to assign them to two different temporal cohorts.
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The Potential of Bulk and Amino-Acid Specific Isotope Ratio Mass Spectrometry of Human Hair in Forensic and Clinical ApplicationsAn, Yan 07 June 2013 (has links)
No description available.
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Mapping biosphere strontium isotope ratios across major lithological boundaries : a systematic investigation of the major influences on geographic variation in the 87Sr/86Sr composition of bioavailable strontium above the Cretaceous and Jurassic rocks of EnglandWarham, Joseph Olav January 2011 (has links)
Strontium isotope analysis has provided archaeologists with an unprecedented opportunity to study the mobility of humans and animals in the past. However, a lack of systematic environmental baseline data has seriously restricted the full potential of the analytical technique; there is little biosphere data available against which to compare measured skeletal data. This thesis examines the extent to which geographic variation in biosphere 87Sr/86Sr composition can be spatially resolved within the lowland terrain of England, in a geographically and geologically coherent study area. Systematically collected samples of vegetation, stream water and surface soils, including new and archived material have been used. The potential of these sample media to provide reliable estimates of the ⁸⁷Sr/⁸⁶Sr composition of bioavailable strontium are evaluated under both high-density and low-density sampling regimes, and against new analyses of local archaeological material. Areas lying south of the Anglian glacial limit, display a pattern of geographic ⁸⁷Sr/⁸⁶Sr biosphere variation (0.7080-0.7105) controlled by solid geology, as demonstrated by high-density biosphere mapping. Data collected at a wider geographic scale, including above superficial deposits, indicate the dominant influence of re-worked local rocks on the biosphere. These methods have enabled a reclassification of the archaeologically important Cretaceous Chalk domain. Analysis of rainwater and other indicators of atmospheric deposition show that, in this setting, local biosphere variation is not significantly perturbed by atmospheric inputs. Time-related data from archaeological cattle and sheep/goat tooth enamel suggest that the modern biosphere data can be used to understand livestock management regimes and that these are more powerful than using an average value from the enamel. A more complete understanding of possible patterns of mobility in a group of humans has been achieved through analysis of material from Winchester and comparison with the Chalk biosphere domain.
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Nearshore habitat and land-use effects on trophic interactions and growth of largemouth bass and bluegill in Indiana's glacial lakesPatricia A Nease (7469945) 17 October 2019 (has links)
Glacial lakes, such as those in the Midwest region
of the United States, are ecologically and economically important, and they
provide a wide range of ecosystem services, such as habitat for wildlife and
fishes, flood control and recreational boating. Glacial lakes often support
locally important sport fisheries, such as largemouth bass <i>Micropterus salmoides</i> and bluegill <i>Lepomis macrochirus</i>,<i> </i>which
are partially dependent on suitable habitat within lakes. Nearshore vegetation
is often removed by lakeshore landowners for perceived aesthetics and boat
access, or by area managers as a form of indirect fisheries management and
invasive species control. The connection between nearshore vegetation and fish
population health, though widely studied is somewhat unclear. In the two
research chapters of this thesis we attempted to further understanding of the
environmental factors that influence vegetation abundance and distribution, how
vegetation abundance and distribution influences fish population abundance and
size structure, and how young-of-year (YOY) largemouth bass utilize habitats
within the nearshore environment. In the first research chapter, we used
structural equation modeling (SEM) and data collected by the Indiana Department
of Natural Resources to quantify the complexity of relationships among catchment
characteristics (e.g., catchment size), lake morphology, water quality,
vegetation abundance and distribution, and fish population abundance and size
structure. Across multiple lakes, lake productivity was more influential in
explaining cross-lake variation of largemouth bass and bluegill proportional
stock density (PSD) and largemouth bass catch per unit effort (CPUE) than
vegetation. This may be a result of the feedback between phytoplankton
production and rooted vegetation production. The models we constructed provide
insights into the complexity of environmental variables that influence
nearshore vegetation and fish populations. In the second research chapter we
used stable isotopes (δ<sup>13</sup> Carbon, δ<sup>15</sup> Nitrogen, δ<sup>18</sup>
Oxygen and δ<sup>2</sup> Hydrogen) to examine the consistency of habitat use
and foraging of YOY largemouth bass within Indiana glacial lakes. We observed
spatial variation in stable isotope ratios of YOY largemouth bass between
habitat types and sites. Additionally, there were significant, positive
relationships between δ<sup>13</sup>C of locally collected potential prey items
and δ<sup>13</sup>C of YOY largemouth bass suggesting localized foraging patterns.
Later in the summer, as young bass grew in size and likely switched to
piscivory, we did not observe similar spatial variation in young bass stable
isotopes or spatial relationships between prey and the young bass suggesting
more homogeneous foraging patterns. Understanding the habitat use patterns of
young bass may allow for more efficient and effective management of the
nearshore environment. Overall, a greater consideration for the complexity of
relationships between nearshore habitat and fish populations may facilitate
more effective management.
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NIR-diode laser spectroscopy for isotope-selective sensing of soil-respired carbon dioxideHörner, Gerald, Lau, Steffen, Löhmannsröben, Hans-Gerd January 2004 (has links)
The performance of a home-built tunable diode laser (TDL) spectrometer has been optimized regarding multi-line detection of carbon dioxide in natural gases. In the regime of the (30<SUP>0</SUP>1)<SUB>III</SUB> ← (000) band of <SUP>12</SUP>CO<SUB>2</SUB> around 1.6 μm, the dominating isotope species <SUP>12</SUP>CO<SUB>2</SUB>, <SUP>13</SUP>CO<SUB>2</SUB>, and <SUP>12</SUP>C<SUP>18</SUP>O<SUP>16</SUP>O were detected simultaneously. In contrast to most established techniques, selective measurements are performed without any sample preparation. This is possible since the CO<SUB>2</SUB> detection is free of interference from water, ubiquitous in natural gases. Detection limits in the range of a few ppmv were obtained for each species utilizing wavelength modulation (WM) spectroscopy with balanced detection in a long-path absorption cell set-up. Linear calibration plots cover a dynamic range of four orders of magnitude, allowing for quantitative CO<SUB>2</SUB> detection in various samples, like soil and breath gas. High isotopic resolution enables the excellent selectivity, sensitivity, and stability of the chosen analytical concept. The obtained isotopic resolution of typically ± 1.0 ‰ and ± 1.5 ‰ (for 3 vol. % and 0.7 vol. % of CO<SUB>2</SUB>, respectively) offers a promising analytical tool for isotope-ratio determination of carbon dioxide in soil gas. Preliminary experiments on soil respiration for the first time combine the on-line quantification of the overall carbon dioxide content with an optode sensor and isotopic determination (TDL system) of natural gas species.
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Peruvian Pinnipeds as Archivists of ENSO EffectsEdwards, Mickie Rae 07 December 2018 (has links)
Environmental fluctuations in the eastern Pacific Ocean are reflected in the tissues of some of its most vulnerable apex predators, the Peruvian fur seal (PFS) Arctocephalus australis ssp.and the South American sea lion (SASL) Otaria byronia.These large pinnipeds live in sympatry along the Pacific coastline of South America and forage within the neritic waters over the continental shelf. The coastal waters off Peru are a region of great environmental fluctuations due to periodic, oscillating El Niño- La Niña- Southern Oscillation (ENSO) events, which result in ecosystem-wide food web changes. Pinniped vibrissae (whiskers) are continuously growing keratinous tissues and reflect the incorporation of prey from the region. Fine resolution sampling along their length provided trophic information on a weekly to monthly time scale over several years. Vibrissae were obtained from 2010-2016 from female (n=47), male (n=17) and newborn pup (n=6) fur seals and male (n=6) sea lions collected during pinniped rookery health assessments. Stable isotope ratios (δ13C and δ15N) in vibrissae infer temporal primary production and dietary variations in individuals. ENSO conditions were dictated by the sea surface temperature anomaly (SSTA) recordings from the Niño 1+2 Index region over 12 years. Fluctuations in vibrissae δ15N were correlated to varying SSTA readings (p15N (p15N signatures (p13C revealed minor fluctuations ranging from -18.13 to -13.17‰over the 12-year period, δ13C did reveal a significant depletion and enrichment oscillation during specific points in time, such as the 2014-2016 El Niño event, which ranged from -15.09 to -13.83‰(p=0.040). Stable isotope signatures varied between genders, but not by species. Female fur seal stable isotope signatures were significantly more depleted in both δ13C and δ15N than males (p13C and δ15N were inversely correlated to each other from 2014 to 2016; this was during the strongest El Nino-Southern Oscillation event on record (p=0.002). As δ13Csignatures became more enriched, δ15N signatures depleted from 2014 until 2016. This suggests that when ENSO warm phase conditions occur, the environments resources change in historic foraging grounds, possibly forcing pinnipeds to travel farther distances offshoreto forage or altering what they feed on throughout these stressful conditions.This study serves to help understand of the impact of oceanographic influences on these pinnipeds.ENSO conditions influence the trophic dynamics and resultant survival adaptations in both of these vulnerable Peruvian marine mammals.
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Reconstruction of Northeastern Pacific Ocean Holocene Production Using Marine Mammal ArchaeofaunaTraffichini, Andrea M 26 July 2019 (has links)
Changes in marine production play a key role in determining the trophic structure of the northeastern Pacific Ocean. This is a region of great environmental fluctuations due to modern, historical, and paleo-environmental variability recorded throughout the Holocene. These fluctuations are recorded in the bone collagen of the marine mammals that reside in these waters. Marine mammal remains from four previously excavated archaeological deposits on Unalaska Island, Alaska are used as a proxy for marine production changes throughout the Holocene (4,500 BP to 350 BP). Historic and modern samples from museum collections, subsistence harvests, and previously published data provide a distinct contrast to prehistoric marine mammals. Stable carbon and nitrogen isotope ratios (δ13C and δ15N) derived from marine mammal bone collagen correlate to changes in marine production and food web length. The 13C and 15N of prehistoric marine mammal taxa covary through the Holocene, indicating no trophic level change with fluctuations in 13C. Changes in δ13C and δ15N of marine mammals are correlated to periods of environmental fluctuations within the Holocene. Cooler climatic periods (transitional interval, beginning of the Neoglacial Interval, and Little Ice Age) show enrichedδ13C, reflecting primary production increase, compared to warmer climate periods (end of the Neoglacial Interval into the Medieval Climatic Anomaly). Unidentified cetacean bones are isotopically distinguishable into orders Mysticeti (baleen) and Odontoceti (toothed) due to different feeding ecologies. The δ13C depletion in modern pinnipeds compared to prehistoric is likely caused by the effect of increased anthropogenic atmospheric CO2 and resulting decrease in primary production.
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Mapping biosphere strontium isotope ratios across major lithological boundaries. A systematic investigation of the major influences on geographic variation in the 87Sr/86Sr composition of bioavailable strontium above the Cretaceous and Jurassic rocks of England.Warham, Joseph O. January 2011 (has links)
Strontium isotope analysis has provided archaeologists with an unprecedented opportunity to study the mobility of humans and animals in the past. However, a lack of systematic environmental baseline data has seriously restricted the full potential of the analytical technique; there is little biosphere data available against which to compare measured skeletal data.
This thesis examines the extent to which geographic variation in biosphere 87Sr/86Sr composition can be spatially resolved within the lowland terrain of England, in a geographically and geologically coherent study area. Systematically collected samples of vegetation, stream water and surface soils, including new and archived material have been used. The potential of these sample media to provide reliable estimates of the 87Sr/86Sr composition of bioavailable strontium are evaluated under both high-density and low-density sampling regimes, and against new analyses of local archaeological material.
Areas lying south of the Anglian glacial limit, display a pattern of geographic 87Sr/86Sr biosphere variation (0.7080¿0.7105) controlled by solid geology, as demonstrated by high-density biosphere mapping. Data collected at a wider geographic scale, including above superficial deposits, indicate the dominant influence of re-worked local rocks on the biosphere. These methods have enabled a reclassification of the archaeologically important Cretaceous Chalk domain. Analysis of rainwater and other indicators of atmospheric deposition show that, in this setting, local biosphere variation is not significantly perturbed by atmospheric inputs.
Time-related data from archaeological cattle and sheep/goat tooth enamel suggest that the modern biosphere data can be used to understand livestock management regimes and that these are more powerful than using an average value from the enamel. A more complete understanding of possible patterns of mobility in a group of humans has been achieved through analysis of material from Winchester and comparison with the Chalk biosphere domain. / British Geological Survey¿s British University Funding Initiative
(BUFI) and the School of Life Sciences at the University of Bradford joint funding.
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Influence des apports rhodaniens sur les traits d'histoires de vie de la sole commune (Solea Solea) : apports de l'analyse structurale et minéralogique des otolithes.Morat, Fabien 15 December 2011 (has links)
La sole commune présente au cours de son cycle de vie un changement ontogénétique d’habitat. Les larves sont marines et pélagiques, les juvéniles sont benthiques et vivent dans les nourriceries côtières (lagunes et estuaires) alors que les adultes sont benthiques et marins en zones plus profondes. Les otolithes sont des concrétions minéralisées de carbonate de calcium de l’oreille interne des téléostéens qui ne subissent ni dissolution ni résorption. Ils enregistrent les caractéristiques chimiques et isotopiques des milieux traversés.L’étude de la croissance, de la composition chimique et isotopique des otolithes des soles des nourriceries a confirmé l’existence de deux stocks de soles dans le golfe du Lion, un à l’Est et l’autre à l’Ouest. Les faibles valeurs de 13C et les fortes valeurs de Ba/Ca des otolithes des soles de l’Est du golfe ont été associées à une forte influence des apports rhodaniens sur la phase de vie larvaire lors des années où le débit du Rhône est normal. En période de crue, une forte influence du fleuve est visible sur les otolithes des soles des nourriceries de l’ensemble du golfe. La croissance des otolithes des juvéniles a été plus élevée lorsque la salinité a été proche de 20 et la température comprise entre 20 et 25°C (période estivale). Les signatures des otolithes de Mauguio et Berre ont présenté des 13C et Sr/Ca plus faibles que ceux de Thau (influences plus marines sur les proies et les masses d’eau). La spécificité des signatures chimiques et isotopiques des otolithes a permis d’élaborer des profils qui ont été retrouvés chez les populations de soles adultes du golfe, mais aussi vers Marseille et Bandol. Ces soles ont montré une influence du Rhône durant la phase de vie larvaire à 53%. Elles ont également montré une forte similarité avec les profils chimiques de type lagune de Thau (10-56%) et Rhône (19-30%) durant leur vie juvénile. Toutefois, une proportion non négligeable de soles originaires de nourriceries non caractérisées (26-50%) a été observée. / The life cycle of the common sole shows an ontogenetic shift of habitats. The larvae are marine and pelagic, the juveniles are benthic in coastal nurseries (lagoons and estuaries) whereas adults are benthic and live in marine deeper areas. Otoliths are paired calcified structures from the inner ear of teletost fish. They are metabolically inert (neither resorption nor dissolution) and they record, both the age (daily and annual increments) and the chemical and isotopic characteristics of the environment inhabited. Otoliths study provides information on the life history traits of individuals.The study of growth, chemical and isotopic otolith composition of soles from nurseries confirmed the existence of two sole stocks in the Gulf of Lions, one in the Eastern part and the other in the Western part. Low values in 13C and higher values in Ba/Ca ratio measured in Eastern sole otoliths during the larval life were associated to a high influence of the Rhône River discharge during a normal flow rate periods. Conversely, the one hundred return flood of the 2nd of December 2003 was very high and visible on otoliths from all nurseries in the Gulf of Lions. Juvenile otolith growth was higher in nurseries with low salinity (~20) and temperatures between 20 and 25°C than in more marine nurseries. 13C and Sr/Ca ratios of otoliths from Berre and Mauguio coastal lagoons were lower than those observed in Thau coastal lagoon (more marine influences on preys and water masses). These specificities of otolith compositions were used for the elaboration of reference profiles, which have been identified in adult populations of the Gulf of Lions, Marseilles and Bandol. Adult have shown an influence of the Rhône River during their larval life at 53%. They have shown a similarity with Thau chemical profile (10-56%) and Rhône profile (19-30%) during their juvenile life. However, 26-50% of fish from uncharacterised nurseries have been observed.
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