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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Stable Isotopes And Multiple Tissue Analysis: Reconstructing Life Histories For Individuals From Dakhleh Oasis, Egypt

Johns, Noel 01 January 2012 (has links)
Stable isotope analysis is often used to evaluate elements of the lives of past peoples, such as diet and health status, at a societal level. Analysis at an individual level is exceptionally rare, and has not been conducted using a variety of tissues representing both early life and life approximate to death. In this study, δ 13C and δ15N isotope signatures are used to create life histories for single individuals from Romano-Christian period Kellis 2 cemetery in the Dakhleh Oasis, Egypt. Samples are obtained from several different tissues, including tooth dentin, bone collagen, hair, nail, skin, and gut content, all of which have been previously researched, but have not been studied at such an individualistic level. By using data and previous research conducted by Drs. Tosha Dupras and Lana Williams, this research uses isotopic values from the aforementioned tissues, and the differing turnover rates of these tissues, to develop lifetime timetables for 15 individuals (female, male, and juvenile). Results show that individual analysis is possible, informative, and can enlighten researchers not just concerning the individual, but about the population as a whole. The methods presented can serve as a model for reconstructing individual life histories using isotope data from multiple tissues.
52

Age As A Factor In Inter-tissue Spacing Of Stable Carbon Isotope Values In Juvenile Human Remains From The Dakhleh Oasis, Egypt

Norris, Annie Laurie 01 January 2012 (has links)
Although stable isotope analysis is routinely utilized in bioarchaeology and relies on principles that are well-understood, there are still fundamental issues that have not been thoroughly investigated. This thesis examines the relationship between inter-tissue spacing of carbon stable isotope values (δ13C) and age in juvenile human remains. Analyses of tissues within the same individual reveal disparate isotopic values for a variety of physiological and biological reasons discussed herein. This project examines the distance between the δ13C values in bone collagen, skin, hair, and nail, and examines how these distances vary between different age groups, utilizing data collected from 52 well-preserved human remains from the Dakhleh Oasis, Egypt: 28 individuals between the ages of 1 and 4 years, 14 between 5 and 10 years, and 10 between the ages of 11-15 years. The mean carbon isotope values for each tissue were compared across each age group, and used to calculate the differences between each tissue type. Although distances between tissues were found to vary across all age categories, the distances between collagen and hair, collagen and skin, and collagen and nail are all substantially greater in the 11-15 year old category than those in the 1-4 and 5-10 year categories. Possible physiological, developmental and social factors are discussed in an effort to explain this discrepancy
53

Childhood diet: a closer examination of the evidence from dental tissues using stable isotope analysis of incremental human dentine

Beaumont, Julia, Gledhill, Andrew R., Lee-Thorp, Julia A., Montgomery, Janet 29 August 2013 (has links)
No / Incremental dentine analysis utilizes tissue that does not remodel and that permits comparison, at the same age, of those who survived infancy with those who did not at high temporal resolution. Here, we present a pilot study of teeth from a 19th-century cemetery in London, comparing the merits of two methods of obtaining dentine increments for subsequent isotope determination. Covariation in ¿13C and ¿15N values suggests that even small variations have a physiological basis. We show that high-resolution intra-dentine isotope profiles can pinpoint short-duration events such as dietary change or nutritional deprivation in the juvenile years of life.
54

The Great Irish Famine: identifying starvation in the tissues of victims using stable isotope analysis of bone and incremental dentine collagen

Beaumont, Julia, Montgomery, Janet 13 July 2016 (has links)
Yes / The major components of human diet both past and present may be estimated by measuring the carbon and nitrogen isotope ratios (δ13C and δ15N) of the collagenous proteins in bone and tooth dentine. However, the results from these two tissues differ substantially: bone collagen records a multi-year average whilst primary dentine records and retains timebound isotope ratios deriving from the period of tooth development. Recent studies harnessing a sub-annual temporal sampling resolution have shed new light on the individual dietary histories of our ancestors by identifying unexpected radical short-term dietary changes, the duration of breastfeeding and migration where dietary change occurs, and by raising questions regarding factors other than diet that may impact on δ13C and δ15N values. Here we show that the dentine δ13C and δ15N profiles of workhouse inmates dating from the Great Irish Famine of the 19th century not only record the expected dietary change from C3 potatoes to C4 maize, but when used together they also document prolonged nutritional and other physiological stress resulting from insufficient sustenance. In the adults, the influence of the maize-based diet is seen in the δ13C difference between dentine (formed in childhood) and rib (representing an average from the last few years of life). The demonstrated effects of stress on the δ13C and δ15N values will have an impact on the interpretations of diet in past populations even in slow-turnover tissues such as compact bone. This technique also has applicability in the investigation of modern children subject to nutritional distress where hair and nails are unavailable or do not record an adequate period of time. / This study was supported by an Arts and Humanities Research Council grant funding to JB under AHRC Studentship AH/I503307/1.
55

A calf for all seasons? The potential of stable isotope analysis to investigate prehistoric husbandry practices

Towers, Jacqueline R., Jay, Mandy, Mainland, Ingrid L., Nehlich, O., Montgomery, Janet 30 March 2011 (has links)
Yes / The Early Bronze Age barrows at Irthlingborough and Gayhurst in central England are notable for the large number of cattle (Bos taurus) remains associated with their human Beaker burials. Previous work using strontium isotope analysis has indicated that most of the cattle analysed, and one aurochs (Bos primigenius), were of local origin (Towers et al. 2010). In this study, stable isotope analysis of enamel and bone was carried out to investigate whether the mature cattle had experienced similar husbandry practices, climate and environment. Bulk carbon, nitrogen and sulphur isotope analysis of collagen suggested most were consuming similar sources of plant protein from environments probably local to the sites and this was supported by high resolution intra-enamel carbon isotope profiles. Oxygen isotope profiles indicated the aurochs and most of the cattle experienced similar climatic regimes: the only exception being an animal with a non-local strontium isotope ratio. However, a comparison of seasonality profiles of the local animals using estimated tooth formation times showed that there was no consistency in season of birth: the animals appeared to have been born throughout the year. Cattle can breed throughout the year but it requires considerable human effort and intervention to successfully overwinter young stock; it is therefore unlikely to have been carried out without good reason and benefit if winters were harsh. One reason is to ensure a continuous supply of milk. Measuring oxygen isotope profiles to identify year-round calving may thus be a potential indicator of dairying economies.
56

The importance of animal baselines: using isotope analysis to compare diet in a British medieval hospital and lay population

Bownes, J., Clarke, Leon J., Buckberry, Jo 08 November 2017 (has links)
Yes / The results of carbon and nitrogen isotope analysis from two medieval populations are presented here, in a study investigating dietary habits within a medieval hospital population in England. We used δ13C and δ15N measurements of bone collagen in order to attempt to identify a distinct group diet within the medieval hospital of St. Giles, Brough, Yorkshire, and examine the reasons why the dietary habits within the institution may have been noticeably different from that of a comparative lay population. Following the results and tentative conclusions of a study conducted by Müldner and Richards (2005), it was hypothesised that religious fasting rules would result in there being evidence of greater consumption marine fish at St. Giles than at the rural township of Box Lane, Pontefract, Yorkshire. While more dietary variation was found at the hospital, it can be seen that the differences in δ13C and δ15N isotope values vary in relation to the animal baselines. Thus, differences between the human populations can be attributed to geological and environmental factors as opposed to dietary differences.
57

Exploring the Relationship Between Nutrition and Cribra Orbitalia: The Comparison of Dietary Stable Isotope Comparisons of Juveniles from Kuelap, Peru

Osorio, Lissette S 01 January 2022 (has links)
A juvenile’s dependency on their caregiver is significant to the overall development of nutritionally related pathological lesions. However, not all skeletal pathology is caused by nutritional stress; despite anemia being the usual inferred cause, the origin of Cribra Orbitalia (CO) – lesions on the orbital roofs of the cranium– is undetermined. The purpose of this research is to compare the reconstructed diets of juveniles with and without CO and explore connections to dietary patterns (inferred from stable isotope ratios of carbon and nitrogen). Rib bone samples of 79 juveniles with and without CO were sampled from the Kuelap archaeological site in Chachapoyas, Peru (AD 800–1532) – known for its archaeological diversity. Stable isotope analysis was conducted (δ13C and δ15N values) to statistically analyze each group’s values. Samples were further subdivided into age cohorts of infants (0–3 years), juveniles (4–11 years), and adolescents (12–18 years). The diets of juveniles with and without CO were determined to have no statistically significant difference between each other. However, a significant statistical difference did exist between the diets of the different juvenile age cohorts regardless of CO status, indicating that weaning and early dietary transitions through childhood affected the juvenile’s nutritional regime in the region. The research presented is the first study of the relationship between nutrition and CO from Kuelap; significantly, it further explores the lifestyle of past individuals in Chachapoyas through the understanding of childhood diets.
58

Feeding the Children: A Paleodietary reconstruction of Juveniles from Kuelap, Peru

Denierio, Marley 01 January 2018 (has links)
Before reaching adulthood, every individual experiences a period of dependency, the juvenile period, during which they rely on the older, more experienced members of their society for their security, subsistence and care. This juvenile period is an important stage of life for human physical and physiological development. In bioarchaeology, there has been limited research conducted on juveniles, particularly, the development of their own social identity and influences. The research method of stable carbon (C) and nitrogen (N) isotope analysis is used to reconstruct the paleodiet of juveniles to determine their dietary composition. Specifically, this research is focused on Kuelap, located in the highlands of Peru, a large settlement inhabited from 900-1535 AD, including pre-Inca (900-1469 AD) and Inca periods (1470-1535 AD). The primary aim of this research is to determine if juveniles consumed different foods through different time periods. Another aim of this research is to determine if juveniles were treated differently than their adult counterparts. Bone collagen samples, primarily ribs, from 32 juveniles were analyzed. The average δ13C value for the pre-Inca juveniles was –13.1‰, and –13.4‰ for the Inca period juveniles. There was no statistically significant difference in δ13C values between juvenile groups or between adult and juvenile subsamples. The average δ15N for the pre-Inca juveniles was +8.1‰ and +7.8‰ for the Inca period juveniles. The Mann-Whitney U test determined there was not a statistically significant difference in δ15N values between the juvenile burial groups; however, there was a statistically significant difference between the juvenile and adult subgroups. The findings suggest that there may have been preferential treatment toward or metabolic stressors on the juvenile. The results of this study offer insights to availability of dietary components, societal roles based on developmental age stages, and the potential role of parenting in Kuelap.
59

Assessing Migration and Demographic Change in pre-Roman and Roman Period Southern Italy Using Whole-Mitochondrial DNA and Stable Isotope Analysis / The Biogeographic Origins of Iron Age Peucetians and Working-Class Romans From Southern Italy

Emery, Matthew 06 1900 (has links)
Assessing population diversity in southern Italy has traditionally relied on archaeological and historic evidence. Although informative, these lines of evidence do not establish specific instances of within lifetime mobility, nor track population diversity over time. In order to investigate the population structure of ancient South Italy I sequenced the mitochondrial DNA (mtDNA) from 15 Iron Age (7th – 4th c. BCE) and 30 Roman period (1st – 4th c. BCE) individuals buried at Iron Age Botromagno and Roman period Vagnari, in southern Italy, and analyzed δ18O and 87Sr/86Sr values from a subset of the Vagnari skeletal assemblage. Phylogenetic analysis of 15 Iron Age mtDNAs together with 231 mtDNAs spanning European prehistory suggest that southern Italian Iapygians share close genetic affinities to Neolithic populations from eastern Europe and the Near East. Population pairwise analysis of Iron Age, Roman, and mtDNA datasets spanning the pan-Mediterranean region (n=357), indicate that Roman maternal genetic diversity is more similar to Neolithic and Bronze Age populations from central Europe and the eastern Mediterranean, respectively, than to Iron Age Italians. Genetic distance between population age categories imply moderate mtDNA turnover and constant population size during the Roman conquest of South Italy in the 3rd century BCE. In order to determine the local versus non-local demographic at Vagnari, I measured the 87Sr/86Sr and 18O/16O of composition of 43 molars, and the 87Sr/86Sr composition of an additional 13 molars, and constructed a preliminary 87Sr/86Sr variation map of the Italian peninsula using disparate 87Sr/86Sr datasets. The relationship between 87Sr/86Sr and previously published δ18O data suggest a relatively low proportion of migrants lived at Vagnari (7%). This research is the first to generate whole-mitochondrial DNA sequences from Iron Age and Roman period necropoleis, and demonstrates the ability to gain valuable information from the integration of aDNA, stable isotope, archaeological and historic evidence. / Thesis / Doctor of Philosophy (PhD) / With biochemical information obtained from teeth, this study examines the population structure and geographic origins in two archaeological communities located in southern Italy. Analysis of classical remains has traditionally been the subject of historical and archaeological inquiry. However, new applications evaluate these population changes with integrated stable isotope and ancient DNA techniques. Overall, the biochemical results suggest that the pre-Roman communities harbor deep maternal ancestry originating from eastern Europe and the eastern Mediterannean. These results, when compared to the genetic diversity of Roman and broader Mediterranean populations, indicate that the Romans share closer genetic similarity with ancient Stone and Bronze Age communites from Europe and the eastern Mediterranean, than with the pre-Roman community studied here. Furthermore, tooth chemistry results indicate a predominantly local population buried in the Roman period cemetery.
60

Patterns and pathways of lead contamination in mottled ducks (Anas fulvigula) and their habitat

Kearns, Brian Vance January 1900 (has links)
Doctor of Philosophy / Department of Biology / David A. Haukos / Mottled ducks (Anas fulvigula) are dabbling waterfowl species native to coastal wetlands of the Gulf of Mexico of the United States and Mexico. Although closely related to common waterfowl species such as the mallard (A. platyrhynchos) and American black duck (A. rubripes), the mottled duck exhibits unique behavior, mainly in its life history as a non-migratory species. As such, because of population declines caused by predation, habitat destruction, and environmental contaminants, this species requires specialized conservation concerns and species-specific management to protect population numbers. The goal of this study was to assess ongoing effect of observed lead (Pb) contamination and exposure issues in mottled ducks and their habitats, which I achieved by conducting assessments that will provide managers habitat and organism level metrics to detect and mitigate lead in mottled ducks and their environments. My field study was conducted at the Texas Chenier Plain National Wildlife Refuge Complex (TCPC), which was the area of greatest mottled duck density on the Texas Coast. I first created a body condition index to provide managers a tool to monitor population health, and a proxy for lead exposure and avian health without destructively sampling individuals. I then used presence-only maximum entropy (MaxENT) and multivariate statistical modeling procedures in conjunction with mottled duck movement data to elucidate sets of habitat conditions that were conducive to predicting the occurrence of mottled ducks and environmental lead “hot spots”. MaxENT analyses suggested that lead in the top portion of the soil column is similarly related to all environmental variables considered, may be increasingly available after large-scale environmental disturbances. Lack of variation in coarse-scale habitat use between breeding and non-breeding seasons may further point to a food-based exposure pathway for lead as mottled ducks switch from an invertebrate to plant diet, either as a result of changing age classes or normal adult phenology, during the period of increased lead exposure. Using stable isotope ratio analysis, I then tested environmental samples of soil and vegetation as well as mottled duck blood to determine isotopic signatures that were consistent with particular sources of lead deposition (e.g., lead shot pellets, leaded fossil fuel combustion, industrial effluents). Comparisons suggested a great deal of similarity to lead shot reference values in vegetation and blood samples, especially in blood samples with higher concentrations of lead present. Last, I conducted a formal Ecological Risk Assessment (ERA) procedure to quantify the risk to mottled ducks from lead exposure in their current habitat and direct managers towards effective mitigation and habitat management strategies to reduce exposure in the future. One scenario suggested that mottled ducks were at greatest risk from eating an invertebrate-based diet, but lead content values at the TCPC suggest that a plant-based diet may provide a higher lead exposure risk for mottled ducks, depending on true levels of bioavailability in environmental media. Overall, I determined that mottled ducks experience greatest lead exposure risk from lead shot pellets on the TCPC or in nearby habitat, while potentially also experiencing low levels of exposure from several other sources. Additionally, management efforts that focus on plants that do not provide food resources for mottled ducks as a potential environmental sink for lead contamination, such as phytoremediation, may prove effective in reducing the overall lead load from historical activities that likely deposited much of the lead in this ecosystem.

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