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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

Dietary ecology of Chacma baboons (Papio Ursinus (Kerr, 1972) and Pleistocene Cercopithecoidea in Savanna environments of South Africa

Codron, Daryl Mark January 2003 (has links)
Bibliography: leaves 124-140. / This dissertation deals with the dietary ecology of savanna-dwelling chacma baboons (Papio ursinus), and a number of fossil cercopithecoids, from modern and Pleistocene environments of South Africa, respectively, using principles of stable light isotope ecology. Previous studies of baboon ecology, based largely on direct observations, have not quantified spatial and temporal dietary variability. The dietary ecology of fossil cercopithecoids is even less clear.
2

The Western Palaearctic evolution of the water vole Arvicola

Ruddy, Mark January 2011 (has links)
The water vole is common in Middle and Late Pleistocene temperate Palaearctic faunas. It is widely used in biostratigraphy because of tem- poral trends in the size, shape and structure of the first lower molar (M1). However, geographic variation in the evolutionary development of the M1 has restricted the precision and accuracy of age-estimations. This thesis explores morphological variation in the M1 of fossil and extant populations of the lineage Mimomys savini–Arvicola, and uses the phenotype and the genotype to develop evolutionary hypotheses. Geometric and traditional morphometric methods are used to quantify tooth shape and enamel thickness from over 4000 digital photographs of M1s taken from specimens originating from 146 modern and fossil groups across the western Palaearctic. M1s are photographed to ob- tain a true cross-section, giving a more accurate description of molar shape. Morphological variation is explored in terms of sample-size, taphonomy, and ontogeny. Sample sizes of less than 10 are likely to provide inaccurate summary statistics of morphometric variables but depositional type appears to have no systematic effect on within-group variation. Change in the morphology of M1s through ontogeny is an im- portant source of morphological variation, explaining up to 29% of mo- lar shape within-specimens and up to 95% of enamel thickness within enamel layers of specimens. Removal of ontogenetic variation from mo- lar shape improves congruence between morphological and molecular data, indicating age-corrected variables should be used when assessing evolutionary patterns. Temporal and spatial patterns in the enamel thickness quotient (SDQ), based on age-corrected enamel thicknesses, mirror those from published data but differ in some details. Method- ological differences mean absolute SDQ values cannot be compared. Qualitative patterns include a large decrease in SDQ across MIS 12 and a steep east–west morphocline during the late Middle Pleistocene.
3

Stratigraphy, provenance and glaciodynamic origins of the Lowestoft till of eastern England

Fish, Paul Ross January 2000 (has links)
No description available.
4

Modellering av Siljans strandkant omkring tidigmesolitisk tid för att identifiera arkeologiskt intressanta platser

Sahlin, Anders January 2017 (has links)
During the planning stages of new business start-ups in Leksand, it was decided that an archaeological survey of the area in question was to be performed in 2013. The reason for this was that in the 1980s findings of Stone Age character had been found in the clay field that once was there. In the 2013 survey, it was found that the area is a stone age settlement, dating back close to 9, 600 BP ( early mesolithic age). Stone age settlements are usually very close to rivers or lakes. For this reason, there arenormally no archaeological surveys of areas not adjacent to water. But this settlement was found on a clay field, 100 meters from the nearest water, Limsjön.The reason for this is that the water level at the time of the settlement's construction was higher in the ground than today. This is b ecause of the uplift of land that occurs in Sweden. The settlement, which was built close to 10,000 years ago was built when the water level was about 10 meters above todays water level at Limsjön. The purpose of this work is to produce maps showing where the whole Siljan shore line was at the time when the first people settled there. This will be done using information for the water surface position close to the settlement from 10,000 years ago to. The old shore line is several 10’s of kilometers long. To get more specific areas the maps also show suitable settlement areas based on the soil types that people have settled on during that time. These maps will then be used as a supportfor choosing areas where archaeological surveys might be of interest. / Under planeringen av nya företagsetableringar i Leksand valde man att 2013 utföra en arkeologisk undersökning av det aktuella området. Anledningen var att man på 1980-talet funnit fynd av stenålderskaraktär i den leråker som låg där då. I undersökningen framkom det att området är en stenåldersboplats, daterad till som äldst omkring 9 600 BP ( tidigmesolitisk tid). Stenåldersboplatser finns i regel i mycket nära anknytning till vattendrag och sjöar. Av denna anledning görs det normalt sett inga arkeologiska undersökningar av denna typ om området inte ligger intill vatten. Men denna boplats hittades alltså på en leråker, 100 meter från det närmsta vattnet, Limsjön. Anledningen till detta är att vattennivån vid tiden för boplatsens uppförande låg högre upp i terrängen än vad den gör idag. På grund av landhöjningen har vattenytans nivå sjunkit i terrängen. Boplatsen som uppfördes för nära 10 000 år sedan uppfördes när vattenytan låg cirka 10 meter högre upp i terrängen vid Limsjön. Syftet med detta arbete är att utifrån information för vattenytans läge vid boplatsen för 10 000 år sedan ta fram kartor som visar var hela Siljans strand låg i terrängen för tiden då de första människorna bosatte sig där. Den forna strandkanten är flera mil lång. För att få fram mer specifika områden ska kartorna även visa områden som är lämpliga boplatsområden, utifrån vilka jordarter som människorna har bosatt sig på under den tiden. Dessa kartor ska sedan kunna användas som underlag för var arkeologiska undersökningar skulle kunna vara intressanta att genomföra.
5

The development and implementation of software for palaeoenvironmental and palaeoclimatological research : the Bugs Coleopteran Ecology Package (BugsCEP)

Buckland, Philip January 2007 (has links)
<p>This thesis documents the development and application of a unique database orientated software package, BugsCEP, for environmental and climatic reconstruction from fossil beetle (Coleoptera) assemblages. The software tools are described, and the incorporated statistical methods discussed and evaluated with respect to both published modern and fossil data, as well as the author’s own investigations.</p><p>BugsCEP consists of a reference database of ecology and distribution data for over 5 800 taxa, and includes temperature tolerance data for 436 species. It also contains abundance and summary data for almost 700 sites - the majority of the known Quaternary fossil coleopteran record of Europe. Sample based dating evidence is stored for a large number of these sites, and the data are supported by a bibliography of over 3 300 sources. Through the use of built in statistical methods, employing a specially developed habitat classification system (Bugs EcoCodes), semi-quantitative environmental reconstructions can be undertaken, and output graphically, to aid in the interpretation of sites. A number of built in searching and reporting functions also increase the efficiency with which analyses can be undertaken, including the facility to list the fossil record of species found by searching the ecology and distribution data. The existing Mutual Climatic Range (MCR) climate reconstruction method is implemented and improved upon in BugsCEP, as BugsMCR, which includes predictive modelling and the output of graphs and climate space maps.</p><p>The evaluation of the software demonstrates good performance when compared to existing interpretations. The standardization method employed in habitat reconstructions, designed to enable the inter-comparison of samples and sites without the interference of differing numbers of species and individuals, also appears to be robust and effective. Quantitative climate reconstructions can be easily undertaken from within the software, as well as an amount of predictive modelling. The use of jackknifing variants as an aid to the interpretation of climate reconstructions is discussed, and suggested as a potential indicator of reliability. The combination of the BugStats statistical system with an enhanced MCR facility could be extremely useful in increasing our understanding of not only past environmental and climate change, but also the biogeography and ecology of insect populations in general.</p><p>BugsCEP is the only available software package integrating modern and fossil coleopteran data, and the included reconstruction and analysis tools provide a powerful resource for research and teaching in palaeo-environmental science. The use of modern reference data also makes the package potentially useful in the study of present day insect faunas, and the effects of climate and environmental change on their distributions. The reconstruction methods could thus be inverted, and used as predictive tools in the study of biodiversity and the implications of sustainable development policies on present day habitats.</p><p>BugsCEP can be downloaded from http://www.bugscep.com</p>
6

Holocene sea-level changes in the Falkland Islands : new insights into accelerated sea-level rise in the 20th Century

Newton, Thomas Lee January 2017 (has links)
This thesis investigates sea-level changes in order to test the hypothesis that the main contribution to early 20th century sea-level rise was Northern Hemisphere land-based ice melt. Multiproxy sea-level reconstructions were established for the Falkland Islands, a location where models suggest sea-level rise from Northern Hemisphere ice melt produces the largest signal. The Falklands reconstruction indicated sea levels in the early 20th century accelerated compared to the long-term rate, synchronous with accelerations observed globally. The magnitude of the acceleration in the Falklands reconstruction was greater than Northern Hemisphere rates, consistent with the spatial pattern from a Northern Hemisphere melt source, but likely less than in New Zealand and Australia. It is therefore not possible rule out other contributions to the observed sea-level acceleration. The Falklands reconstruction indicated a rapid sea-level jump around 8.4 ka BP, synchronous with a jump observed in the Northern Hemisphere, which has been attributed to the sudden drainage of Laurentide proglacial lake Agassiz-Ojibway associated with the 8.2 ka BP climatic downturn. A maximum estimate of 0.89 ± 0.22 m for this jump in the Falklands is considerably less than estimates from Northern Hemisphere records. This difference could indicate additional contributions from the Southern Hemisphere are being recorded in the Northern Hemisphere signal. This thesis also focused on developing testate amoebae as sea-level indicators. In the Falklands, testate amoebae transfer functions were able to reconstruct sea level with precision (±0.08 m) comparable to diatoms (±0.07 m). However, preservation issues were indicated in the fossil testate amoebae assemblages which limits their use as tools for sea-level reconstruction. In addition, contemporary distributions of salt-marsh testate amoebae were investigated over one annual cycle. Seasonal variations in the live assemblages were observed to be asynchronous between taxa. Variations in the death assemblages were also observed which were correlated with variations in the live assemblages. This observation suggests the commonly applied assumption in palaeoenvironmental studies that analysing the death population negates temporal bias is invalid. Further research is required to investigate the impact these observed variations have on reconstructive performance.
7

The biostratigraphy, palaeoecology and geochemistry of a long lacustrine sequence from NW Greece

Frogley, Michael Reginald January 1998 (has links)
Examination of an important new 319m core of lake sediment recovered from Ioannina in NW Greece has attempted to relate changes in the lake to variations in the regional climate of south-central Europe over the last 600,000 years. The site is known to have been extremely sensitive to past climatic change for three reasons: (i) temperate vegetation persisted throughout glacial stages (albeit at low frequencies), so the vegetational response to climatic change would therefore have been almost immediate; (ii) the extreme thickness of the sediments suggests that accumulation rates were high (at times, &gt; 1m per thousand years), which has enabled high-resolution palaeoclimatic reconstructions; and (iii) precipitation of authigenic carbonate has preserved a remarkably sensitive proxy record of productivity variations for most of the lake's history. Well-defined shifts from glacial - interglacial mode have been correlated with vegetational changes identified in a core previously analysed from the same basin (using magnetic susceptibility profiles), enabling tentative correlations to be suggested with other European terrestrial sequences and with the marine oxygen isotope record, back to marine isotope stage 16. Twelve AMS radiocarbon determinations from the upper part of the core, together with the identification of a series of reversed palaeomagnetic events within the Brunhes chron, support the proposed age model for the sequence. The sediments at Ioannina, unlike most of the other long terrestrial European sequences, are calcareous and contain mollusc and ostracod assemblages. Part of this project has involved a comprehensive review of Quaternary and modem aquatic faunas from the lake, as well as the description, illustration and critical assessment of several poorly-known endemic taxa. Faunal assemblage data have been used to provide valuable information concerning the variable response of lake-level to climatic change over time. Convincing new mollusc an evidence indicates low lake-levels at the Last Glacial Maximum, agreeing with regional pollen data, but conflicting with geomorphological evidence derived from Kastritsa, a well-documented nearby Palaeolithic cave site. It is suggested that this discrepancy may be a result of subsequent tectonic uplift of the rockshelter. In addition, stable isotopic analyses of both the ostracods and the bulk carbonate within the sediments have contributed towards deriving a comprehensive palaeoenvironmental history for the site. Although the study analysed physical, biological and geochemical aspects of the entire core, two distinct parts of the record were selected for more detailed investigation. High-resolution analysis over the last interglacial (the Eemian) has revealed evidence for a clear, two-step deglaciation at the beginning of the period, known from elsewhere as the Zeifen-Kattegat Oscillation. Climatic instability has also been detected within the full interglacial. Comparisons are drawn with a range of other Eemian records from across Europe, as well as the Greenland ice cores. High-resolution analysis of the period from the end of the last glacial to the present day has also revealed evidence for climatic instability. A cool and arid oscillation is demonstrated by several climatic proxies that may constitute the first recognition of the Younger Dryas stadial from Greece. A shorter, but more subdued cooling event has also been detected during the first half of the Holocene, which may correspond with a widespread climatic oscillation from high-resolution terrestrial, marine and ice core records that has been dated to between 7,500 and 8,000 years BP.
8

The development and implementation of software for palaeoenvironmental and palaeoclimatological research : the Bugs Coleopteran Ecology Package (BugsCEP)

Buckland, Philip January 2007 (has links)
This thesis documents the development and application of a unique database orientated software package, BugsCEP, for environmental and climatic reconstruction from fossil beetle (Coleoptera) assemblages. The software tools are described, and the incorporated statistical methods discussed and evaluated with respect to both published modern and fossil data, as well as the author’s own investigations. BugsCEP consists of a reference database of ecology and distribution data for over 5 800 taxa, and includes temperature tolerance data for 436 species. It also contains abundance and summary data for almost 700 sites - the majority of the known Quaternary fossil coleopteran record of Europe. Sample based dating evidence is stored for a large number of these sites, and the data are supported by a bibliography of over 3 300 sources. Through the use of built in statistical methods, employing a specially developed habitat classification system (Bugs EcoCodes), semi-quantitative environmental reconstructions can be undertaken, and output graphically, to aid in the interpretation of sites. A number of built in searching and reporting functions also increase the efficiency with which analyses can be undertaken, including the facility to list the fossil record of species found by searching the ecology and distribution data. The existing Mutual Climatic Range (MCR) climate reconstruction method is implemented and improved upon in BugsCEP, as BugsMCR, which includes predictive modelling and the output of graphs and climate space maps. The evaluation of the software demonstrates good performance when compared to existing interpretations. The standardization method employed in habitat reconstructions, designed to enable the inter-comparison of samples and sites without the interference of differing numbers of species and individuals, also appears to be robust and effective. Quantitative climate reconstructions can be easily undertaken from within the software, as well as an amount of predictive modelling. The use of jackknifing variants as an aid to the interpretation of climate reconstructions is discussed, and suggested as a potential indicator of reliability. The combination of the BugStats statistical system with an enhanced MCR facility could be extremely useful in increasing our understanding of not only past environmental and climate change, but also the biogeography and ecology of insect populations in general. BugsCEP is the only available software package integrating modern and fossil coleopteran data, and the included reconstruction and analysis tools provide a powerful resource for research and teaching in palaeo-environmental science. The use of modern reference data also makes the package potentially useful in the study of present day insect faunas, and the effects of climate and environmental change on their distributions. The reconstruction methods could thus be inverted, and used as predictive tools in the study of biodiversity and the implications of sustainable development policies on present day habitats. BugsCEP can be downloaded from http://www.bugscep.com
9

Der glazifluviale Formenschatz im Gletschervorfeld des Himalaya und der Versuch einer relativ-zeitlichen Einordnung / Glaciofluvial sequence of forms in the glacier foreland of the Himalayas and their chronological classification

Tombrink, Gerrit 23 November 2017 (has links)
No description available.

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