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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.
1

Ecogeographic Patterns of Maxillary Sinus Variation Among Homo sapiens: Environmental Adaptation or Architectural By-product?

Butaric, Lauren Nicole 03 October 2013 (has links)
Ecogeographic patterns of modern human craniofacial diversity suggest external nasal structures reflect climatic adaptations for respiratory and thermoregulatory functions. Regarding internal structures, the maxillary sinus supposedly varies as a function of the nasal cavity while not contributing in respiratory function. Owing to conflicting results, this study reinvestigates that claim by evaluating maxillary sinus variation in a larger sample (n=200) spanning 11 ecogeographic regions. The surface-area-to-volume (SA:V) ratio (i.e., relative mucosal area) was collected in addition to sinus volume and linear dimensions. Pearson correlations show nasal cavity breadth and maxillary sinus volume are not significantly correlated, and individuals from cold, versus hot, climates exhibit larger volumes with lower surface-area-to-volume (SA:V) ratios. Individuals from high altitudes display a unique configuration with high SA:V ratios and large maxillary sinus volumes. Analyses of variance largely fail to find significant differences among the 11 samples. However, a canonical variate analysis of nasal and sinus dimensions indicates clear separations between the heat- and cold-adapted populations, as well as among the cold-adapted populations. Specifically, Arctic populations display smaller sinus volumes and lower SA:V ratios. Mantel tests indicate certain sinus dimensions depart from isolation-by-distance models. Results indicate that maxillary sinus form does not simply follow isolation-by-distance models and cannot simply be explained in terms of nasal cavity breadth or craniofacial architecture— suggesting that environmental pressures are directly acting on the sinus. Functional possibilities for the sinus include thermoregulatory functions among Arctic populations and/or nitric oxide production for high-altitude populations. Additional considerations and future lines of research are presented.
2

The Role of Ochre in the Development of Modern Human Behavior: A Case Study from South Africa

January 2012 (has links)
abstract: In recent years, southern Africa has figured prominently in the modern human origins debate due to increasing evidence for precocious behaviors considered to be unique to our species. These significant findings have included bone tools, shell beads, engraved ostrich eggshell, and heavily ground and engraved ochre fragments. The presence of ochre in Middle Stone Age (MSA, ~250-40kya) archaeological sites in southern Africa is often proposed as indirect evidence for the emergence of symbolic or artistic behavior, a uniquely modern human trait. However, there is no remaining artwork from this period and there is significant debate about what the ochre may have been used for. With a few exceptions, ochre has gone largely unstudied. This project tested competing models for ochre use within the Pinnacle Point (PP), South Africa research area. Combined results from characterization and sourcing analyses, color classification, heat treatment analysis, and hafting experiments suggest MSA ochre is tied to early symbolic or ritual behavior. / Dissertation/Thesis / Ph.D. Anthropology 2012
3

Allostatic Load, Senescence, and Aging Among Japanese Elderly

Leahy, Rachael Elizabeth 24 October 2014 (has links)
No description available.
4

La morphologie de la base du crâne et ses relations avec le maxillaire et la mandibule : variations et auxologie

Brondeau, François de 04 December 2008 (has links)
Un examen des relations basicrânio-faciales et leurs variations au cours de l'ontogenèse est réalisé chez l'homme moderne. L'étude de la « typologie » faciale sagittale (classe squelettique) est envisagée en relation avec la configuration de la base du crâne. L'objectif est d'établir un modèle de développement basicrânio-facial conduisant aux différentes typologies faciales de l'homme actuel. - Une première étude bidimensionnelle a pour but de définir les variables de la base du crâne caractéristiques des relations faciales dans les dysmorphoses sagittales extrêmes. Ces résultats soulignent le lien entre flexion de la base du crâne, sa région postérieure et le décalage antéro- postérieur de la face. - Une seconde étude sur scanners Rx s'attache aux interactions entre la dimension transversale et sagittale. Elle confirme l'importance du positionnement antéro-postérieur des structures basicrâniennes dans la conformation faciale sagittale. Elle révèle peu de liens entre la dimension transversale de la base du crâne et les prognathismes maxillaire et mandibulaire, mais souligne l'influence de l'orientation des pyramides pétreuses, de l'écartement des processus ptérygoïdiens et de la flexion sphénoïdale. - Une troisième étude longitudinale analyse l’évolution des variables mises en évidence selon l'âge et le stade d'évolution dentaire pour chaque classe squelettique. Les paramètres basicrâniens ne sont pas prédéfinis à la naissance, ceux décrivant la flexion et la région postérieure de la base du crâne deviennent caractéristiques plus tardivement. Les stades occlusion de la denture temporaire et évolution de la première molaire permanente sont des évènements clés dans le lien entre la base du crâne et le type facial. Un modèle de développement basicrânio-facial est proposé à partir des trois conformations crânio-faciales dégagées (dysmorphoses squelettiques). Des perspectives en anthropologie des populations anciennes et actuelles sont proposées. / Basicranio-facial relationships and their variations during ontogenesis are studied on the modern human. The study of the sagittal facial typology (skeletal class) has been realized in relation with the cranial base shape. The aim was to establish a model of the basicranio-facial development leading to the different facial typologies of modern human. - A first two-dimensional study aims to define the variables of the cranial base caracteristical of the facial relations in the extreme sagittal dysmorphoses. The results show the link between the flexion of the cranial base, its posterior region and the facial antero-posterior discrepancy. - A second study on X-ray scanners looks into the interactions between the transverse and sagittal dimension. The results suggest the importance of the antero-posterior positioning of the cranial structures in sagittal facial shape. This study reveals few relationships between the basicranial transverse dimension and maxillary, mandibular prognathism, but shows the influence of the petrous pyramids orientation, the distance between pterygoid processes and the cranial base angle flexion. - A third longitudinal study analyzes the evolution of the variables observed in relation with the age and the stage of dental evolution for each skeletal class. The basicranial parameters are not predetermined at birth, those describing flexion and the posterior region of the cranial base become characteristic later on. The stages of the deciduous occlusion denture and of the first permanent molar evolution are key events for the link between cranial base and facial type. Based on the three craniofacial shapes described (skeletal dysmorphoses) a basicranio-facial development model is proposed. Perspectives in ancient and modern population anthropology are suggested.
5

Lithic technology and hunting behaviour during the Middle Stone Age in Tanzania

Bushozi, Pastory 06 1900 (has links)
In this dissertation, I examine the representation of projectile points in the Middle Stone Age (MSA) and Later Stone Age (LSA) of Tanzania, and the way in which such tools were used over time and space. This study reviews the different strategies used to produce points during the MSA and LSA. It also examines the mechanisms involved in raw material procurement, hafting technology, and the use of these tools as projectile weapons and how they evolved over time. It is clear that there were different kinds of multi-weapon systems in use in Tanzania during the MSA, LSA and the transition between them. The points examined are from three archaeological sites: Mumba, Nasera and Magubike. They reveal that triangular blanks were preferred for the production of points. Most of them were modified on their proximal ends to provide a suitable binding portion for hafting and aerodynamic movement. Results from the Tip Cross Section Area (TCSA) and weight values suggest that spear and arrow projectiles coexisted in these sites during the MSA and MSA/LSA transition. Both local and exotic rocks were used for the production of points. In previous studies, the appearance of exotic rocks in the archaeological assemblages was correlated with trade and exchange. But here the use of exotics seems to be influenced by functional values such as durability, sharpness and brittleness. Sharp and durable rocks such as chert and quartzite were needed for spears because of their high compression strength. This makes them better able to withstand unintentional breakage after being stressed by the force of impact. Points made of brittle rocks, such as quartz and obsidian, were mainly used for light duty projectiles such as throwing spears (darts) and arrows, because they penetrate the body of an animal better and sometimes break more easily. The presence of points made of exotic or local rocks shows that functional variables were important for projectile technologies. The overall morphological and technological patterns revealed in this study suggest that foragers who made and used points had elaborate technological skills, abstract thinking and developed behavioural capability similar to those of other modern foragers.
6

Lithic technology and hunting behaviour during the Middle Stone Age in Tanzania

Bushozi, Pastory Unknown Date
No description available.
7

All in Good Time: Exploring Change in Neanderthal Behavioural Complexity

Langley, Michelle Unknown Date (has links)
Since their discovery 150 years ago, Neanderthals have been considered incapable of behavioural change and innovation. Traditional synchronic approaches to the study of Neanderthal behaviour have perpetuated this view and shaped our understanding of their lifeways and eventual extinction. In this thesis I implement an innovative diachronic approach to the analysis of Neanderthal faunal extraction, technology and symbolic behaviour as contained in the archaeological record of the critical period between 80,000 and 30,000 years BP. The thesis demonstrates patterns of change in Neanderthal behaviour which are at odds with traditional perspectives and which are consistent with an interpretation of increasing behavioural complexity over time, an idea that has been suggested but never thoroughly explored in Neanderthal archaeology. Demonstrating an increase in behavioural complexity in Neanderthals provides much needed new data with which to fuel the debate over the behavioural capacities of Neanderthals and the first appearance of Modern Human Behaviour in Europe. It supports the notion that Neanderthal populations were active agents of behavioural innovation prior to the arrival of Anatomically Modern Humans in Europe and, ultimately, that they produced an early Upper Palaeolithic cultural assemblage (the Châtelperronian) independent of modern humans. Overall, this thesis provides an initial step towards the development of a quantitative approach to measuring behavioural complexity which provides fresh insights into the cognitive and behavioural capabilities of Neanderthals.
8

Landscape Variability in Tool-Use and Edge Damage Formation in South African Middle Stone Age Lithic Assemblages

January 2016 (has links)
abstract: This study explores how early modern humans used stone tool technology to adapt to changing climates and coastlines in the Middle Stone Age of South Africa. The MSA is associated with the earliest fossil evidence for modern humans and complex cultural behaviors during a time period of dramatic climate change. Human culture allows for the creation, use, and transmission of technological knowledge that can evolve with changing environmental conditions. Understanding the interactions between technology and the environment is essential to illuminating the role of culture during the origin of our species. This study is focused on understanding ancient tool use from the study of lithic edge damage patterns at archaeological assemblages in southern Africa by using image-based quantitative methods for analyzing stone tools. An extensive experimental program using replicated stone tools provides the comparative linkages between the archaeological artifacts and the tasks for which they were used. MSA foragers structured their tool use and discard behaviors on the landscape in several ways – by using and discarding hunting tools more frequently in the field rather than in caves/rockshelters, but similarly in coastal and interior contexts. This study provides evidence that during a significant microlithic technological shift seen in southern Africa at ~75,000 years ago, new technologies were developed alongside rather than replacing existing technologies. These results are compared with aspects of the European archaeological record at this time to identify features of early human technological behavior that may be unique to the evolutionary history of our species. / Dissertation/Thesis / Doctoral Dissertation Anthropology 2016
9

A Formal Modeling Approach to Understanding Stone Tool Raw Material Selection in the African Middle Stone Age: A Case Study from Pinnacle Point, South Africa

January 2017 (has links)
abstract: The South African Middle Stone Age (MSA), spanning the Middle to Late Pleistocene (Marine Isotope Stages (MIS) 8-3) witnessed major climatic and environmental change and dramatic change in forager technological organization including lithic raw material selection. Homo sapiens emerged during the MSA and had to make decisions about how to organize technology to cope with environmental stressors, including lithic raw material selection, which can effect tool production and application, and mobility. This project studied the role and importance of lithic raw materials in the technological organization of foragers by focusing on why lithic raw material selection sometimes changed when the behavioral and environmental context changed. The study used the Pinnacle Point (PP) MSA record (MIS6-3) in the Mossel Bay region, South Africa as the test case. In this region, quartzite and silcrete with dramatically different properties were the two most frequently exploited raw materials, and their relative abundances change significantly through time. Several explanations intertwined with major research questions over the origins of modern humans have been proposed for this change. Two alternative lithic raw material procurement models were considered. The first, a computational model termed the Opportunistic Acquisition Model, posits that archaeological lithic raw material frequencies are due to opportunistic encounters during random walk. The second, an analytical model termed the Active-Choice Model drawn from the principles of Optimal Foraging Theory, posits that given a choice, individuals will choose the most cost effective means of producing durable cutting tools in their environment and will strategically select those raw materials. An evaluation of the competing models found that lithic raw material selection was a strategic behavior in the PP record. In MIS6 and MIS5, the selection of quartzite was driven by travel and search cost, while during the MIS4, the joint selection of quartzite and silcrete was facilitated by a mobility strategy that focused on longer or more frequent stays at PP coupled with place provisioning. Further, the result suggests that specific raw materials and technology were relied on to obtain food resources and perform processing tasks suggesting knowledge about raw material properties and suitability for tasks. / Dissertation/Thesis / Doctoral Dissertation Anthropology 2017
10

Évolution dentaire dans les populations humaines de la fin du Pléistocène et du début de l’Holocène (19000 – 5500 cal. BP) : une approche intégrée des structures externe et interne des couronnes pour le Bassin aquitain et ses marges / Dental evolution in Late Pleistocene and Early Holocene human populations (19000 – 5500 cal. BP) : a whole crown perspective in the Aquitaine Basin, southwest France, and its margins

Le Luyer, Mona 07 January 2016 (has links)
À partir de la fin du Pléistocène, une réduction de la taille des dents humaines et une simplification morphologique ont été observées et débattues en lien avec des changements culturels et environnementaux. Suite à de nouvelles découvertes et à la révision des contextes archéologiques de certains gisements, une réévaluation de la nature des variations de plus de 1900 couronnes dentaires est proposée pour 176 individus de la fin du Paléolithique, du Mésolithique et du début du Néolithique provenant du Bassin aquitain et de ses marges. Particulièrement, les variations de la structure interne (épaisseur de l’émail, proportions des tissus dentaires, morphologie de la jonction émail-dentine) ont été évaluées de manière non invasive grâce aux méthodes d’imagerie 3D (microtomographie) et de morphométrie géométrique afin de caractériser et d’interpréter l’évolution des couronnes dentaires selon une approche intégrée. Les résultats des analyses morphométriques montrent une discontinuité entre les populations de la fin du Pléistocène et celles du début de l’Holocène. Une réduction des dimensions externes, des épaisseurs de l’émail et des proportions des tissus est mesurée entre la fin du Paléolithique et le Mésolithique, alors que des différences majeures dans les types d’usure et la distribution de l’émail sont observées entre le Mésolithique et le Néolithique. Ces données suggèrent que les modifications induites par les changements environnementaux de l’Holocène ont eu un impact plus important sur la réduction dentaire dans les populations humaines et que les changements culturels néolithiques ont surtout affecté la distribution de l’émail. Enfin, une corrélation entre le type d’usure occlusale et la distribution de l’épaisseur de l’émail a été mise en évidence et associée à des changements de régime alimentaire. En particulier, l’épaisseur de l’émail peut évoluer rapidement comme une réponse sélective aux changements fonctionnels dans la biomécanique de la mastication. / Since the Late Pleistocene, a reduction in size and a morphological simplification of human teeth have been observed and arguably linked to cultural and environmental changes. Following new discoveries along with the revision of key archaeological contexts, a re-assessment of the nature of crown variations on more than 1900 teeth is proposed for 176 Late Paleolithic, Mesolithic and Early Neolithic individuals from the Aquitaine Basin and its margins. In particular, a non-invasive assessment of internal tooth structure variability (enamel thickness, dental tissue proportions, enamel-dentine junction morphology) has been performed using 3D imaging methods (microtomography) and geometric morphometrics in order to characterize and interpret dental evolution from a whole crown perspective. Results from the morphometric analyses show a discontinuity between Late Pleistocene and Early Holocene populations. External dimensions, enamel thicknesses and tissue proportions are reduced in Mesolithic individuals compared to those of the Late Paleolithic, while major differences are observed in occlusal wear patterns and enamel distribution between Mesolithic and Early Neolithic samples. These data suggest that environmentally-driven modifications during the Early Holocene had a major impact on dental reduction in human populations and that Neolithic cultural changes had mostly affected enamel distribution. Finally, a correlation between occlusal wear pattern and enamel thickness distribution is observed and associated with dietary changes. In particular, enamel thickness may have rapidly evolved as a selective response to functional changes in masticatory biomechanics.

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