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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.
81

Implications of Late Pleistocene Climatic Change on the Morphological Variations of the Neanderthal

Bradley, Dawn Marie 02 February 2006 (has links)
In this research, the relationship of climatic changes between 130k to 28k years BP to concurrent morphological variations in Neanderthals was tested. Traditional anthropological studies attribute robust Neanderthal morphological traits as an adaptation to a cold environment. A database of previously completed terrestrial paleoclimatic reconstructions in Europe and the Mediterranean was compiled and used to create a series of GIS-generated timeslice maps. Regional climatic conditions were then related to changes in Neanderthal appearances, morphology and disappearances as evident in the archaeological record. To establish climatic conditions, existing studies were compiled from two regions: Europe and the Mediterranean. The European data are based on pollen assemblage sequences from terrestrial lacustrine cores. The Mediterranean data are based on established ƒÔ18O/16O and ƒÔ13C/12C maximum and minimum events recorded in speleothems. The GIS perspective allows these changes to be viewed at significant time to better correlate regional climatic changes with known Neanderthal morphological variation and to extend the investigation both temporally, including Stage 4 and Stage 5e, and geographically, into the Mediterranean from similarly completed studies.
82

Evolutionary History and Biogeography of Papionin Monkeys

Folinsbee, Kaila 19 January 2009 (has links)
Climate change has been invoked to explain patterns of speciation, extinction and biogeographic change over time, however it can be a difficult hypothesis to test empirically. One area of particular interest is climate change in the African Neogene, linked with the origin of hominins. A perfect model clade to test these hypotheses is the papionin monkeys, a diverse group (both extinct and extant), represented by an excellent fossil record. I describe new fossil papionin specimens from Coopers Cave, South Africa, and redescribe and discuss some previously known fossil material. This rich data set provides a necessary deep-time perspective, and, in conjunction with independently generated data, can be used to test hypotheses related to climatic and geological events (such as increasing late Pleistocene aridity and persistence of forest refugia) that may be directly linked to patterns of speciation and biogeographic distribution in the fossil record and in living species. Testing these hypotheses requires a robust phylogenetic hypothesis. I collected morphological character data for a species-level phylogenetic analysis of the papionin clade in order to reconstruct the phylogeny of the group. My analysis found that the living species Theropithecus gelada is nested within extinct theropiths, and is primitive relative to the Pleistocene taxa Theropithecus darti, T. oswaldi and T. leakeyi. Also falling within the theropith lineage are the early Pliocene taxon Pliopapio, the South African taxa Dinopithecus and Gorgopithecus, and two species whose relationships were uncertain until my analysis. “Papio” quadratirostris and “Papio” baringensis are nested within the theropiths, and should be referred to the genus Theropithecus. Biogeographic analysis demonstrates that papionin monkeys share a similar pattern with other Neogene African mammals; they first disperse out of Africa during the mid-Miocene, return to Africa by the late Miocene and undergo a series of vicariant speciation events and range restriction to central Africa, but disperse out into eastern and southern Africa by the Pleistocene. These speciation and dispersal events are tightly correlated with global climatic and tectonic changes.
83

THE INFLUENCES OF QUATERNARY PROCESSES ON NATIVE FRESHWATER DIVERSITY IN PATAGONIA: MOLECULAR INSIGHTS FROM THE GALAXIID FISHES

Zemlak, Tyler Stephen 02 June 2011 (has links)
Using GIS-based tools and a review of the relevant geological and climatic literature, I attempt to identify the key implications of Quaternary glacial cycles for drainage evolution in eastern Patagonia. In doing so, the stage is set for the proper integration of existing biogeographic and phylogeographic ideas to develop a suite of inferences aimed at elucidating how these processes influenced aquatic biodiversity of Patagonian Argentina. A primary finding of this research is that the southern mainland and/or Tierra del Fuego served as an important cryptic refuge for cold-adapted species, including aquatic taxa. At least one additional aquatic refuge is likely to have existed in either central or northern Patagonia. The low position of the Atlantic shoreline during glacial periods also revealed a much larger and inter-connected drainage network in southern Patagonia. During sea-levels stands below 100m, two new drainage coalescence points on the exposed continental shelf can be recognized among the Chico/Santa Cruz, Coyle and Gallegos river basins and between the Grande and Fuego rivers. Enhanced hydrological discharge during the deglaciation period of Late-Quaternary cycles is expected to have facilitated extensive inter-drainage connections within each of the northern and southern regions of eastern Patagonia via proglacial lake and/or stream coalescence. A large proglacial lake in the Nahuel Huapi Lake region is also recognized as the most likely temporary gateway for aquatic organisms to disperse between the Neuquen and Northern Patagonian Tablelands. I also recognize climate-induced drainage reversals as a bidirectional mechanism of trans-Andean dispersal and an important factor in determining the biogeography of widespread aquatic organisms in Patagonia.
84

Later Stone Age and Iron Age Human Remains from Mlambalasi, Southern Tanzania

Sawchuk, Elizabeth A. Unknown Date
No description available.
85

Agate Basin Archaeology in Alberta and Saskatchewan, Canada

Benders, Quinn Unknown Date
No description available.
86

Paleomagnetism of Late Wisconsin lake sediments of southeastern Québec

Tessier, Gérard. January 1983 (has links)
No description available.
87

Reconstructing the last Pleistocene (Late Devensian) glaciation on the continental margin of northwest Britain

Davison, Stephen January 2005 (has links)
The continental margin in the area west of Shetland was subjected to repeated and extensive ice sheet advances during the Late Pleistocene. Seabed imagery, seismic survey and borehole core data show the Late Devensian ice sheets expanded across the continental shelf three times, two of these advances reaching the shelf edge. On the inner shelf, where present-day water depths are generally less than 100m, only thin sediments from the last retreat phase and exposed rock surfaces remain, all other deposits from earlier phases having been removed by the last advance. On the mid to outer shelf elements of all three phases are preserved, including lodgement and deformation tills, melt-out and water-lain till sheets, in-filled hollows left by stagnant ice decaying in situ and a series of large recessional and terminal moraines. In addition, there is evidence of shallow troughs and overdeepend basins which indicate preferential ice-drainage pathways across the shelf which were formerly occupied by ice streams. At the shelf edge, a thick wedge of glacigenic sediment forms a transition from the till sheets and moraines of the shelf to debris flows composed of glacigenic sediments on the upper slope. Shelf-edge moraines show an architecture indicating floating ice in modern water depths over approximately 180m, suggesting the West Shetland ice sheet was no more than about 250m thick. The upper and middle slope is dominated by glacigenic debris flows which are focused in the slope areas below the proposed ice stream discharges at the shelf edge. The mid-to-lower slope has been subjected to contour current activity which has re-worked much of the glacigenic sediment in this position. The lower slope and floor of the Faroe-Shetland Channel are marked by either large debris flow lobes of glacigenic sediment or thin glacimarine muds deposited from suspension. A conceptual model of the glacigenic development of a passive continental margin based upon the West Shetland example shows the deposited sequence for both advance and retreat phases of a glacial cycle, and the actual preserved sequence which might be expected in the rock record. The model also shows that ice sheet buoyancy, thickness, and to a lesser extent, basin subsidence, are the most important factors in the deposition and preservation of a glacially-influenced marine sequence.
88

The use of soil characterization information in the correlation of Wisconsinan-age glacial drift in Randolph County, Indiana

Anderson, Noel P. January 1988 (has links)
The upland soils of Randolph County, Indiana were studied for the following purposes: to provide an additional characterization of these soils, to identify a set of soil parameters that could delineate the extent of Late Wisconsinan glaciation in that county and to determine if there were any geographic trends in silt cap thickness. The study was prompted from observations by the recent Randolph County Soil Survey team that high clay content soils commonly associated with the county's Late Wisconsinan till (Lagro Formation) were found south of its previously mapped boundary.The only soil parameters that were effective in mapping the extent of Late Wisconsinan glaciation were: particle size analyses and some combinations of particle size analysis data with other soil parameters. The data support the previously mapped boundary of the Late Wisconsinan sediments in Randolph County, Indiana.Silt cap thickness was identified to be greatest in three areas of the county. However, the source(s) of these silts could not be determined. / Department of Geology
89

Evolutionary History and Biogeography of Papionin Monkeys

Folinsbee, Kaila 19 January 2009 (has links)
Climate change has been invoked to explain patterns of speciation, extinction and biogeographic change over time, however it can be a difficult hypothesis to test empirically. One area of particular interest is climate change in the African Neogene, linked with the origin of hominins. A perfect model clade to test these hypotheses is the papionin monkeys, a diverse group (both extinct and extant), represented by an excellent fossil record. I describe new fossil papionin specimens from Coopers Cave, South Africa, and redescribe and discuss some previously known fossil material. This rich data set provides a necessary deep-time perspective, and, in conjunction with independently generated data, can be used to test hypotheses related to climatic and geological events (such as increasing late Pleistocene aridity and persistence of forest refugia) that may be directly linked to patterns of speciation and biogeographic distribution in the fossil record and in living species. Testing these hypotheses requires a robust phylogenetic hypothesis. I collected morphological character data for a species-level phylogenetic analysis of the papionin clade in order to reconstruct the phylogeny of the group. My analysis found that the living species Theropithecus gelada is nested within extinct theropiths, and is primitive relative to the Pleistocene taxa Theropithecus darti, T. oswaldi and T. leakeyi. Also falling within the theropith lineage are the early Pliocene taxon Pliopapio, the South African taxa Dinopithecus and Gorgopithecus, and two species whose relationships were uncertain until my analysis. “Papio” quadratirostris and “Papio” baringensis are nested within the theropiths, and should be referred to the genus Theropithecus. Biogeographic analysis demonstrates that papionin monkeys share a similar pattern with other Neogene African mammals; they first disperse out of Africa during the mid-Miocene, return to Africa by the late Miocene and undergo a series of vicariant speciation events and range restriction to central Africa, but disperse out into eastern and southern Africa by the Pleistocene. These speciation and dispersal events are tightly correlated with global climatic and tectonic changes.
90

Agate Basin Archaeology in Alberta and Saskatchewan, Canada

Benders, Quinn 11 1900 (has links)
This thesis documents Agate Basin archaeological remains in the provinces of Alberta and Saskatchewan. By extension, it examines the context of the rapidly changing Late Pleistocene/Early Holocene environment. A database of information on Agate Basin sites in the study area is assembled. Site analysis allowed for the examination of Agate Basin adaptations based on radiocarbon chronology, landform use, mobility, resource use, projectile point production and climate and environmental context. The results confirm that Agate Basin producing peoples within Alberta and Saskatchewan displayed variability concerning projectile point production, landscape use, resource extraction, and hunting practice. It appears that Agate Basin producing people within Alberta and Saskatchewan practiced a predominantly broad-based strategy for procuring resources. No evidence exists to support a model of large-scale communal hunting. Likely, the strongest influence on the particular adaptive behaviours of Agate Basin producing people in Alberta and Saskatchewan can be summarized as environmental.

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