Dissertations / Theses on the topic 'Palaeoecology'
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Witton, Mark P. "The palaeoecology and diversity of pterosaurs." Thesis, University of Portsmouth, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496607.
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The taxonomy and locomotory methods of pterosaurs have been extensively scrutinised for as long as pterosaurs themselves have been known, but comparatively little research has been conducted into their lifestyles and habits. Pterosaurs have largely been interpreted as Mesozoic equivalents of modem marine birds, principally foraging through flight-based methods of dip- or skim-feeding. Here, several lines of enquiry suggest that pterosaurs were considerably more ;ologically diverse that previously anticipated.
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Macpherson, Allan J. "Ecological resilience at semi-arid and temperate boundaries of the Mediterranean-type Fynbos Biome, South Africa, during the Holocene." Doctoral thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/25357.
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Mediterranean-type ecosystems are amongst the most vulnerable to global change. Threats from desertification are projected due to rapid expansion of adjacent semiarid systems. Changes in fire frequency and intensity can alter ecosystem composition and structure, and potentially facilitate transitions between alternative stable states. Given the outstanding biodiversity of the Mediterranean-type fynbos biome in the Greater Cape Floristic Region (GCFR) of South Africa, understanding of the longterm impacts of global change are particularly important. In this study, palaeoecological data are used to assess the effects of changes in climate, fire and land use on vegetation at the semi-arid and temperate margins of the fynbos biome. Previous palaeoecological studies have shown stable fynbos during the recent geologic past, which restricts interpretation of the long-term ecological processes that determine biome resilience. This study sourced sediment cores directly from presentday fynbos-succulent karoo (semi-arid) and fynbos-afrotemperate forest biome boundaries to emphasise ecological dynamics. Fossil pollen, spores and charcoal were extracted from radiocarbon dated sediment cores to provide proxies for vegetation, hydrology, large herbivore abundance and fire. Constrained hierarchical clustering (CONISS), optimal sequence splitting by least-squares, and Non-metric Multidimensional Scaling (NMDS) was applied to the fossil data to identify distinct assemblages in the record, and to further elucidate ecosystem trajectories through time. At the semi-arid boundary at Groenkloof (5,500 cal yrs BP - near present), decreased moisture and fire from 4,000-735 cal yrs BP allowed colonisation of fynbos by a possible 'no-analogue' community dominated by Asteraceae and Poaceae. From 735 cal yrs BP however, climatic amelioration allowed fynbos to re-establish. The system can therefore be viewed as resilient through a capacity for 'recovery' and persistence through turnover in internal composition of fynbos taxa. This sensitive response to climatic forcing reflects the dominant influence of physiological stress at the semiarid limits of Mediterranean-type ecosystems, as well as a Gleasonian type community composition with loose species associations. In contrast, ecosystem
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Saunders, Kate Marie. "Silurian dendroid graptolites : taxonomy, palaeoecology and biostratigraphy." Thesis, University of Portsmouth, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343388.
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Price, Gilbert J. "Pleistocene palaeoecology of the eastern Darling Downs." Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16271/1/Gilbert_Price_Thesis.pdf.
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Several late Pleistocene fossil localities in the Kings Creek catchment, Darling Downs, southeastern Queensland, Australia, were examined in detail to establish an accurate, dated palaeoecological record for the region, and to test human versus climate change megafauna extinction hypotheses. Accelerator Mass Spectrometry (AMS 14C) and U/Th dating confirm that the deposits are late Pleistocene in age, but the dates obtained from the two methods are not in agreement. Fluvial depositional accumulation processes in the catchment reflect both high-energy channel and low-energy episodic overbank deposition. The most striking taphonomic observations for vertebrates in the deposits include: 1) low representation of post-cranial elements; 2) high degree of bone breakage; 3) variable abrasion but most identifiable bone elements with low to moderate degree of abrasion; 4) low rates of bone weathering; 5) low degree of carnivore bone modification; and 6) low degree of articulated or associated specimens. Collectively, those data suggest that the material was transported into the deposit from the surrounding proximal floodplain and that the assemblages reflect hydraulic sorting. A multifaceted palaeoecological investigation revealed significant habitat change between superposed assemblages of site QML796. The basal fossiliferous unit contained species that indicate the presence of a mosaic of habitats including riparian vegetation, vine thickets, scrubland, open and closed woodlands, and open grasslands during the late Pleistocene. Those woody and scrubby habitats contracted over the period of deposition so that by the time of deposition of the youngest horizon, the creek sampled a more open type environment. Sequential faunal horizons show a step-wise decrease in taxonomic diversity that cannot be explained by sampling or taphonomic bias. The decreasing diversity includes loss of some, but not all, megafauna and is consistent with a progressive local loss of megafauna in the catchment over an extended interval of time. Collectively, those data are consistent with a climatic cause of megafauna extinction, and no specific evidence was found to support human involvement in the local extinctions. Better dating of the deposits is critically important, as a secure chronology would have significant implications regarding the continent-wide extinction of the Australian megafauna.
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Price, Gilbert J. "Pleistocene palaeoecology of the eastern Darling Downs." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16271/.
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Several late Pleistocene fossil localities in the Kings Creek catchment, Darling Downs, southeastern Queensland, Australia, were examined in detail to establish an accurate, dated palaeoecological record for the region, and to test human versus climate change megafauna extinction hypotheses. Accelerator Mass Spectrometry (AMS 14C) and U/Th dating confirm that the deposits are late Pleistocene in age, but the dates obtained from the two methods are not in agreement. Fluvial depositional accumulation processes in the catchment reflect both high-energy channel and low-energy episodic overbank deposition. The most striking taphonomic observations for vertebrates in the deposits include: 1) low representation of post-cranial elements; 2) high degree of bone breakage; 3) variable abrasion but most identifiable bone elements with low to moderate degree of abrasion; 4) low rates of bone weathering; 5) low degree of carnivore bone modification; and 6) low degree of articulated or associated specimens. Collectively, those data suggest that the material was transported into the deposit from the surrounding proximal floodplain and that the assemblages reflect hydraulic sorting. A multifaceted palaeoecological investigation revealed significant habitat change between superposed assemblages of site QML796. The basal fossiliferous unit contained species that indicate the presence of a mosaic of habitats including riparian vegetation, vine thickets, scrubland, open and closed woodlands, and open grasslands during the late Pleistocene. Those woody and scrubby habitats contracted over the period of deposition so that by the time of deposition of the youngest horizon, the creek sampled a more open type environment. Sequential faunal horizons show a step-wise decrease in taxonomic diversity that cannot be explained by sampling or taphonomic bias. The decreasing diversity includes loss of some, but not all, megafauna and is consistent with a progressive local loss of megafauna in the catchment over an extended interval of time. Collectively, those data are consistent with a climatic cause of megafauna extinction, and no specific evidence was found to support human involvement in the local extinctions. Better dating of the deposits is critically important, as a secure chronology would have significant implications regarding the continent-wide extinction of the Australian megafauna.
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Sexton, Philip. "Foraminiferal taphonomy, palaeoecology and palaeoceanography of the Eocene." Thesis, University of Southampton, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416473.
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Hart, Sean Fraser. "Palaeoecology of Lower Cambrian and Lower Ordovician reefs." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361669.
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Emson, D. "The ecology and palaeoecology of diatom-duckweed relationships." Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1462713/.
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This thesis focuses on the ecology and palaeoecology of diatom-duckweed relationships and utilises a combined experimental, ecological and palaeoecological approach. In particular, the study sought to determine the potential of the epiphytic diatom Lemnicola hungarica to be utilised as a proxy indicator of past dominance of duckweed (Lemna) in small ponds. To this end, contemporary sampling of epiphytic diatom assemblages from a variety of macrophytes (including multiple samples of free-floating plants) were collected from around the world and analysed for diatom epiphytes. In this study, even despite significant environmental gradients, L. hungarica showed a significant association with free-floating plants (including Lemna spp.) as did Sellaphora seminulum. To determine whether this relationship might be used to infer Lemna-dominance in sediment cores, diatom assemblages were analysed in surface sediments from English Lemna and non-Lemna covered ponds and in a core from a pond (Bodham Rail Pit, eastern England) known to have exhibited periods of Lemna-dominance in the past. In both cases, the data suggested that both L. hungarica and S. seminulum were excellent predictors of past Lemna-dominance. Finally, to infer the consequences of Lemna-dominance for the long-term biological structure and ecosystem function of the Bodham Rail Pit, the sedimentary remains of diatoms, plant pigments, and plant and animal macrofossils were enumerated from two sediment cores. These stratigraphic data were compared with the diatom Lemna-indicator metric which indicated three distinct Lemna cycles. Sediment core analyses suggested major compositional, structural and ecological changes brought about by the Lemna cycles, especially in the submerged macrophyte community and in fish-invertebrate relationships. These data reveal that duckweed proliferation, often brought about by eutrophication and terrestrialisation in ponds, can result in dramatic ecological changes due to a strong physical ecosystem engineering effect.
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Glenwright, Thomas Lane. "Diatom-based palaeoecology of Kowloon Bay, Hong Kong." Thesis, Click to view the E-thesis via HKUTO, 2000. http://sunzi.lib.hku.hk/hkuto/record/B42575576.
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Glenwright, T. Lane. "Diatom-based palaeoecology of Kowloon Bay, Hong Kong /." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22032423.
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Parker, Adrian Glenn. "Late quaternary environmental change in the Upper Thames Basin, central-southern England." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320933.
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Collins, Philip E. F. "Floodplain environmental change since the last glacial maximum in the Lower Kennet Valley, South-Central England." Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294864.
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The lower Kennet Valley terraces reflect fluctuations in river regime through the Quaternary. Sediments and valley floor geomorphology provide a detailed record of Devensian and Flandrian fluvial behaviour and environmental change. Two major surfaces occur, the floodplain and the Beenham Grange Terrace (2 - 3m above the floodplain). Levelling showed that the terrace south of the river, underlain by deposits of two Early Devensian interstadials, was part of the Beenham Grange level, and not the Thatcham Terrace as previously proposed. The fluvial succession consisted of the subflood plain Midgham Peat Formation overlying the Woolhalllpton Gravel Formation The latter also rises to form the surface of the Beenham Grange Terrace adjacent to the floodplain. A subunit of the Woolhampton Formation, the Heales Lock Gravel Member, thickened over a large depression in the local Tertiary bedrock and was associated with syndepositional subsidence which aided excellent subfossil preservation in the sediments. A major channel fill within the member - the Wasing Sand Bed - contained Betula with a distinctive herb flora which, with 14C data, indicates a correlation with the Late Devensian Windermere Interstadial. Lithostratigraphy, biostratigraphy and 14C data from gravels resting unconformably on the Wasing Sand indicated a Loch Lomond Stadial age. The sedimentology of the Midgham Peat Formation reflected early Flandrian reductions in flow competence associated with silt, peat and tufa deposition. Regional woodland expansion was followed by alder can' closing of the floodplain during the Atlantic. A subsequent hiatus ended ,with Sub-boreal (?Bronze Age) flooding and deposition, perhaps anthropogenically induced. An upper silt reflects lower energy flooding in an agricultural landscape. To avoid taphonomic difficulties macrofossil interpretations utilised only well-preserved material. Pollen taphonomy was more problematic. A pilot study in subarctic Canada suggested that, while fluvial pollen assemblages were not exactly equivalent to regional pollen rain through local inputs and sorting, vegetation changes were identifiable.
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Gearey, Benjamin Richard. "Human-environmental relations on Bodmin Moor during the Holocene." Thesis, University of Plymouth, 1996. http://hdl.handle.net/10026.1/511.
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Plewes, Caryl Robin. "Ichnotaxonomic studies of Jurassic endoliths." Thesis, Aberystwyth University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339375.
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Lumley, Susanne Helen. "Late Quaternary vegetational and environmental history of the Taitao Peninsula, Chile." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320035.
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Al-Sayigh, Abdul Razak Siddiq. "Lower Tertiary Foraminifera from south east Oman." Thesis, Aberystwyth University, 1999. http://hdl.handle.net/2160/1a8d5b93-df4b-412e-aecb-38c02de78e03.
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Over 250 samples were collected over three field seasons from the SE Oman Mountains. Fortyone species of planktonic Foraminifera (belonging to 7 genera) and twenty-eight species of larger benthonic Foraminifera, (belonging to 13 genera) are figured (both by SEM and optical photography) from the Wadi Musawa and Wadi Suq sections. Nine planktonic foraminiferal zones are formally recognised between the Upper Palaeocene(P 4) and upper Middle Eocene (P14). The known stratigraphic distribution of these species was used to recognise the zones P 5, P8-P9 as equivalentt o standard zones of Blow, 1969,1979, whilst strata considered generally equivalent to P4 and PIO-PI4 in the Wadi Musawa section are zoned on the basis of the local range. Younger sediments can only be dated on larger Foraminifera. A possible hiatus representing the planktonic zones P 6/P7 is tentatively identified. Fifteen lithostratigraphic units are recognised and formally described from three formations: the Abat Formation( units A-D), the Musawa Formation (units E-L) and the Tahwah Formation (units M-0). The ages of the Abat and Musawa formations are redefined and are shown to be significantly older than previously published. Biostratigraphical and palaeoenvironmental data from both the planktonic and the larger Foraminifera has been used in conjuction with the lithostratigraphy to construct a sequence stratigraphy, in which several cycles have been recognised. Some of these cycles may correlate with the global sea-level cycles of Haq et al. (1987) and include TA2.3 and TAM, Whilst others are local due to tectonically induced regressive and transgressive events. Information not only from the Foraminifera but also from radiolaria, ostracods and molluscs has been used to reconstruct the palaeoenvironment for the Omani Palaeogene. Parts of the Lower and Middle Eocene contain in-situ larger Foraminifera indicating deposition in a shelf (dominantly mid to outer) setting. During the late Palaeocene, most of the early Eocene, part of the middle Eocene, and the entire late Eocene/early Oligocene mixed assemblages of planktonics and shallow water benthonics were the dominant Foraminifera. The occurrence of the these two assemblages in deepwater sediments indicates a substantial period of time in which penecontemporaneous uplift and resedimentation of carbonate shelf deposits into deeperwater occurred. A number of new larger and smaller benthonic Foraminifera are described and one planktonic foraminifer renamed.
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Day, Susan Petronella. "History and palaeoecology of woodlands in the Oxford region." Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257822.
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Davidson, Thomas Alexander. "Zooplankton ecology and palaeoecology of nutrient enriched shallow lakes." Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1444372/.
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This study sought to determine the potential of sedimentary cladoceran assemblages for inferring changes in shallow lake ecological structure and function. The first stage of the study aimed to isolate and quantify the main structuring forces of the contemporary zooplankton community. Zooplankton populations were sampled from 39 mesotrophic to hyper-eutrophic shallow lakes (<3 m average depth) in the U.K. and Denmark. Additionally, a suite of environmental variables, including: fish, macrophytes, algal crop, nutrient concentrations and water transparency were analysed. A variety of numerical techniques including constrained ordination and logistic regression were employed to determine whole community and individual species response to the environmental variation within the data set. The sedimentary remains of zooplankton were then enumerated from the surface sediments of the 39 'training set' lakes. These data were compared with the contemporary counts. Despite differential preservation of sedimentary remains, the main factors structuring the assemblages were the same in both data sets, zooplanktivorous fish density (ZF) and submerged macrophyte abundance (MA). Furthermore, these factors displayed a similar degree of influence on both assemblages. A multivariate regression tree (MRT) was used to calibrate sedimentary cladoceran assemblage response to ZF and MA. The resultant model places a site in one of five groups based on cladoceran assemblage and corresponding to a range of values of ZF and MA. These groups represent distinct forms of ecosystem structure and function varying from sites with clear water, abundant macrophytes and low ZF to turbid, phytoplankton dominated systems with high ZF. Sedimentary cladoceran assemblages from dated cores for two sites, Felbrigg Lake (Norfolk, England) and Kenfig Pool (Glamorgan, Wales) were analysed. The cladoceran inferred ZF and MA indicated that both sites have undergone dramatic changes in ZF and MA. Comparison with plant macrofossil data and historical records at both sites indicated the veracity of the model.
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Grant, Michael James. "The palaeoecology of human impact in the New Forest." Thesis, University of Southampton, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427406.
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McMullen, John Andrew. "Palaeoecology and the conservation management of lowland raised bogs." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310749.
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Johnson, Kate. "Late quaternary palaeoecology and phylogenetics in southern South America." Thesis, Queen's University Belfast, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.675928.
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Vegetation in South America has been impacted by multiple Pleistocene glacial events, climatic changes, volcanic eruptions, fire and human settlement on different temporal and spatial scales. Vegetation dynamics have been inferred from previous pollen studies, but some areas remain vastly understudied, despite the presence of suitable palaeoecological sites. Impenetrable volcanic tephra layers often restrict the ages of these sediments, limiting the age of palaeoecological studies. Combining palaeoecology with phylogenetics increases our understanding of the timing and spatial changes of vegetation movement. Two lake sediment sequences in central Argentina were analysed for pollen, and the phylogenetic history of two trees (the threatened Araucaria araucana and disjunctly distributed Lomatia hirsuta) were studied to better understand the postglacial movement of these species. Pollen indicated that vegetation has been relatively stable for the last 5,000 cal. yr BP in the region, with major changes (such as the introduction of Pinus sylvestris, and opening of the forest canopy) occurring only with the arrival of European settlers around 150 years ago. Populations of Araucaria araucana expanded after the Last Glacial Maximum, but also survived in situ at the edge of the Northern Patagonian glaciers. Preliminary analysis of ancient DNA from Araucaria araucana shows the species' range has not changed in 2,500 cal. yr BP. Lomatia hirsuta is disjunctly distributed due to long-distance dispersal, although research in this thesis was not able to refine the timing of this population split. This research successfully reconstructed the vegetation history from two lakes during the late Holocene, and highlights the complexity of vegetation response to natural and anthropogenic forcings.
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Ballantyne, Fiona. "Palaeoecology and vegetation dynamics in the Cederberg wilderness area." Master's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/6227.
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The Cederberg Wilderness Area, in the Cape Floristic Region, South Africa, contains over 2000 plant species, 280 of which are endemic. The area has been subject to various forms of land use for millennia ranging from hunter-gatherers, herders, and farmers to visitors today. This study used palaeoecological techniques to investigate the impacts of past land use, specifically the transition from hunter-gathering to farming and herding in order to provide a baseline for current wilderness management. A sediment core was extracted from a wetland adjacent to the De Rif farmstead, analysed for fossil pollen and charcoal and dated using AMS radiocarbon dating. Historical records were used to link changes with land use history. A vegetation survey of the site focussed on the grass component of the vegetation. The largest impacts on vegetation during the last 2300 years are due to grazing and agriculture during the 1800s to 1940. Fire-sensitive taxa have not declined, apart from possibly Ericaceae, suggesting that changes in fire have not exceeded a threshold that affects the community at a family level. Changes in the fire regime, combined with disturbance by ploughing and grazing have increased the abundance of Poaceae and Cyperaceae, resulting in a decrease in Restionaceae. Ploughing affected the height structure and species composition of the site, and allowed the invasion and persistence of exotic grasses which now make up 43% of total grass cover on the previously ploughed area. Few indigenous fynbos grasses were found suggesting that the grass community is depauperate due to disturbance. The higher grass abundance preceded the largest fire recorded in the charcoal record suggesting a grass fire cycle has started at De Rif. Ploughing, grazing and invasive grasses, rather than changes in fire regime or resource extraction, are the main causes of vegetation change at De Rif and still affect the site today. Wilderness management will need to mitigate the impacts of livestock and agriculture on De Rif and monitor the recovery of this and other previously farmed areas to ensure that they do not become as a source of invasive species in the future under novel disturbances such as anthropogenic climate change.
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Davies, Fay Mary. "Holocene palaeoenvironmental studies in the Oban region, western Scotland." Thesis, University of Newcastle upon Tyne, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337378.
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Williams, Ann Cerys. "Palaeoecological and palaeoenvironmental variations in the Callovian, Oxfordian and Kimmeridgian (Jurassic) of Britain." Thesis, University of Leicester, 1988. http://hdl.handle.net/2381/34984.
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Carbon and oxygen stable isotope analyses have been performed on well preserved calcareous fossils from Callovian, Oxfordian and Kimmeridgian (Jurassic) mudrock facies of Britain. Assemblages of ammonites, bivalves and belemnites have been sampled from the Lower Oxford Clay of the English Midlands, the Kimmeridge Clay of Wiltshire and the Dorset coast, and the Staffin Shale Formation of Skye. In this way it was hoped to cover a wide stratigraphic and geographic range. Carbon isotope stratigraphy reveals a positive excursion in the Callovian, which is interpreted as an oceanic anoxic event. On the basis of palaeontological and sedimentological evidence, the Callovian has long been viewed as a time of oxygen deficiency. These views are supported by this, the first detailed isotopic study of the stage. A comparison of the 613 C values of the ammonites and infaunal bivalves reveals a major anomaly, in that the latter show very positive values. Tentative suggestions are put forward to account for this. Oxygen isotope (and hence palaeotemperature) stratigraphy reveals a cooling through the Upper Callovian and Oxfordian, consistant with the "Boreal spread" of Arkell (1956), with a warming into the Lower Kimmeridgian. Palaeotemperature variations within individual assemblages raise important questions about palaeoecology. On the basis of this data, it appears that bivalves previously considered to be nekto - or pseudoplanktonic did not occupy the upper reaches of the water column. Suggestions have been made that ammonites were benthic rather than nektonic, but the evidence presented here implies that this was not the case. Relative to the rest of the assemblage, belemnite temperatures tend to be low, highlighting their migratory nature. Boreal ammonites are found to precipitate their shells in cooler waters than those from the Tethyan Realm. The significance of this, and other factors, in terms of controls on provinciality are discussed.
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Gardner, Neville P. "Small-scale distribution of two modern land snail faunas : islands and boundaries of relevance to the interpretation of subfossil assemblages." Thesis, Cardiff University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315293.
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Barnes, Ian. "The molecular identification of goose species in archaeozoological assemblages." Thesis, University of York, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298376.
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Williams, James Philip. "Small mammal deposits in archaeology : a taphonomic investigation of Tyto alba (barn owl) nesting and roosting sites." Thesis, University of Sheffield, 2001. http://etheses.whiterose.ac.uk/10250/.
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Small mammals have often been utilised as indicators of past environments. Before palaeoecological assessments can be made, investigations into the origin and mode of deposition are carried out. Many small mammal accumulations are predator-derived, and in order to take account of predatory bias in these deposits, it is necessary to identify the predator. Several methodologies have catalogued patterns of bone modification from dietary waste of modern predators, for comparison with taphonomic features found on archaeological assemblages of small mammals. The majority of this research has concentrated only on the adult age range from these predators. However, data from owls have shown that younger individuals are often responsible for more extensive bone modification. To investigate this difference associated with the age of predators and bone modification, two modern Tyto alba roost samples and three modern Tyto alba nest samples were analysed to provide evidence of bone modification from adult and baby owls. Significant differences were found between these two groups, with higher rates of bone digestion associated with the nest samples, To test whether these taphonomic patterns could be identified in archaeological deposits, small mammal assemblages from four archaeological sites (The Old Vicarage at Tadcaster, Filey Roman Signal Station, Fox Hole Cave and Carsington Pasture Cave) were analysed. At one of these sites, bone digestion matched that of the Tyto alba nest sites. Bone digestion at the other three sites was higher than that recorded in this study for either Tyto alba adults or their young. This study has shown that it is possible to recognise owl nests in the archaeological record, and concludes that analysis of these assemblages can elucidate not only the origin of specific predator deposits, but can also be used to investigate the nature of human occupation, usage and abandonment of these sites.
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Adams, Terence Gilbert. "The late holocene vegetation history of Lake Farm, South Eastern Cape Province, South Africa." Master's thesis, University of Cape Town, 1994. http://hdl.handle.net/11427/14715.
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Bibliography: p. 155-175.Palynological analysis of organic sediments from a freshwater lake near Port Elizabeth (34°S,25°30'E) has provided a high- resolution vegetation history of the area for the last 2200 years. Detailed identification and counting of the fossil pollen resulted in the generation of a pollen diagram. Changing frequencies in fossil pollen over time are represented, and inferences are made regarding environmental conditions which influenced the vegetation. A detailed narrative of vegetation history in response to environmental change is presented, and this is compared to results from related studies. The significance of the Lake Farm study site has been noted in terms of its location as a 'zone of convergence' for a variety of vegetation types. Results of fossil pollen analysis indicate that environmental conditions prior to 1 500BP were drier than at present. Forest and fynbos vegetation were not well-represented in the pollen spectrum at this time, and it is suggested that they were not favoured by these conditions. Environmental conditions ameliorated after 1500BP, becoming more mesic, which favoured the proliferation of both forest and fynbos vegetation types. At present xeric and grassland elements are declining, while shrubs increase, indicating an enhanced human-induced disturbance regime. It is suggested that the partial decline in forest elements at present 1s most likely attributable to human-induced disturbance of the environment. The introduction of exotic trees has been noted (approx. 280BP) and is seen to have coincided with the influx of european settlers to the region. Principal Components Analysis has revealed that the vegetation distribution in the area has been most heavily influenced by human activity and moisture availability. The necessarily subjective interpretation of the statistical results, however, casts some doubt on the validity of the conclusions drawn. The validity of the conclusions drawn from this study becomes apparent not only in terms of what is learned about the history of forests, but also the form any future management should take.
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Foster, William J. "Palaeoecology of the late Permian mass extinction and subsequent recovery." Thesis, University of Plymouth, 2015. http://hdl.handle.net/10026.1/5467.
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Climate warming during the latest Permian is associated with the most severe mass extinction event of the Phanerozoic, and the expansion of hypoxic and anoxic conditions into shallow shelf settings. Our understanding of the magnitude, pattern and duration of the extinction event and subsequent recovery remains equivocal. Evidence suggests that the action of waves provided an oxygenated refuge, i.e. ‘habitable zone’, above wave base that may be limited to high latitudes, in association with a faster pace of recovery. In addition, advanced recovery faunas have been documented from the Induan and there is evidence from the pelagic realm that further biotic crises may have delayed the recovery of benthic organisms coinciding with large carbon isotope perturbations at the Lower Triassic sub-stage boundaries. To test these hypotheses, novel palaeoecological data was collected from localities in Hungary, northern Italy, and Svalbard. To understand better the ecological impact of the extinction, a database of all known benthic marine invertebrates from the Permian and Triassic periods was created, with each taxon assigned to a functional group based on their inferred lifestyle. This study found that the skeletal and ichnofaunal assemblages consistent with advanced ecological recovery are limited to settings aerated by wave activity, which supports the habitable zone hypothesis. In the western Palaeotethyan sections it was found that the proximal end of the ‘habitable zone’ was limited by persistent environmental stress attributed to increased runoff that resulted in large salinity fluctuations, increased sedimentation rates and eutrophication creating an environment only favourable for opportunistic taxa. In the Tirolites carniolicus Zone, however, the ‘habitable zone’ expands into more proximal and offshore settings. This is associated with climate cooling in the late Spathian. The data also demonstrate that despite the taxonomic severity of the extinction, only one mode of life went extinct and only one subsequently evolved in the aftermath. Functional diversity was, however, reduced in particular regions and environmental settings, and recovery varied spatially and temporally. In western Palaeotethys, benthic communities record evidence for biotic crises, such as reduced tiering in the Smithian, associated with Early Triassic carbon isotope excursions, but, until the Spathian there was no significant change in the composition of the benthic faunas.
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Carthew, Richard. "Palaeoecology of encrusting faunas from the Silurian of Gotland, Sweden." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279915.
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Wooller, Matthew John. "The palaeoecology of Mount Kenya: evidence from grass-cuticle analysis." Thesis, Swansea University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.575147.
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Rosen, D. Z. "Recent palaeoecology and industrial impact on the South Wales landscape." Thesis, Swansea University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638713.
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The increasing extent and diversity of industrial activity throughout South Wales over the past 500 years may have profoundly affected the vegetation. However, few radiometrically-dated pollen diagrams relating to this period have been produced from South Wales, and the precise nature and causes of any ecological change remain uncertain. This study aims to elucidate past vegetation change by constructing radiometrically-dated pollen diagrams from four sites in South Wales, to reconstruct past industrial activity around the study sites using palaeoenvironmental techniques (geochemical, magnetic mineral and spheroidal carbonaceous particle analyses) and to assess whether this industrial activity was a major cause of vegetation change. The pollen diagrams reflect major woodland clearance around Llanllwch Bog (Carmarthenshire) and Crymlyn Bog (Lower Swansea Valley) from the early and mid-nineteenth century respectively. This might be attributable to an increase in demand for industrial land, population growth or agricultural expansion. There is little change in the pollen spectra from Ffoston Cenglau (upland South Wales) or Kenfig Pool (near Port Talbot). Although the palaeoenvironmental records suggest considerable variations in the nature and timing of industrial activity throughout South Wales, this may have occurred outside of the site pollen source areas whilst diagenetic of methodological influences may have affected the palaeoenvironmental profiles. It was therefore often difficult to reconcile the palaeoecological and palaeoenvironmental records. It was shown that site-specific and coring location-specific influences affect the spatial representation and reliability of the palaeoecological and palaeoenvironmental records. As a result, ombrotrophic mires may not be the most suitable depositional context from which to reconstruct past vegetational and industrial change. Detailed documentary evidence can aid data interpretation, but the nature and causes of regional vegetation change may remain undetected. A multidisciplinary approach nonetheless limits the potential for misinterpretation of the evidence for past vegetation change and its underlying causes.
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Virah-Sawmy, Malika. "Using Palaeoecology to address mining - Conservation Conflicts in Southeast Madagascar." Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508661.
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Coombes, Paul Melor Vernon. "The palaeoecology of recent human impact in the Lake District." Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396760.
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Botting, Joseph Peter. "Palaeoecology and systematics of Ordovician biotas from Welsh volcaniclastic deposits." Thesis, University of Birmingham, 2000. http://etheses.bham.ac.uk//id/eprint/5409/.
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The effects of explosive volcanism on local ecosystems are investigated in Middle Ordovician siliciclastics from the Welsh Basin. Bulk sampling analysis has provided quantitative data, regarding population proportions and abundance, following ash deposition in nearshore, shallow dysaerobic basin, and deeper basinal facies. Consistent ecological effects include the destruction of small sessile benthos by rapid burial, followed by re-establishment of mobile and opportunistic taxa, and a bimodal, planktic-benthic bloom in dysaerobic facies. The results are explained through vertical circulation initiated by turbid surface waters following ash deposition. Upwelling of subsurface, nutrient-rich waters of stratified basins is accompanied by downwelling of oxygenated surface waters, entrained into broadly spaced columns. The duration and nature of the events are investigated by ecological, sedimentological, and mechanical approaches, and high sedimentation rate invoked, resulting from seismicity associated with local volcanism. Systematic studies are included on Porifera, Echinodermata and Palaeoscolecida, the unusual preservation of each resulting from volcanism-related processes. The poriferan fauna provides significant information on non-lithistid demosponges and hexactinellids, including the earliest representatives of several groups. Rapid silicification of the proteinaceous skeleton of two species indicates a new source of soft-tissue preservation. Echinoderms comprise the most diverse pre-Caradoc fauna known from Britain, including six crinoids, three asteroids, and a cystoid.
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Mõtus, Mari-Ann. "Silurian (llandovery-wenlock) tabulate corals of Baltoscandia : taxonomy, palaeoecology, distribution /." Tartu: Tartu University Press, 2005. http://dspace.utlib.ee/dspace/bitstream/10062/1292/5/m6tus.pdf.
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Martinez, Sandrine. "Palaeoecology of the Mount Etna bat fauna, coastal Eastern Queensland." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/40979/1/Sandrine_Martinez_Thesis.pdf.
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Global warming is already threatening many animal and plant communities worldwide, however, the effect of climate change on bat populations is poorly known. Understanding the factors influencing the survival of bats is crucial to their conservation, and this cannot be achieved solely by modern ecological studies. Palaeoecological investigations provide a perspective over a much longer temporal scale, allowing the understanding of the dynamic patterns that shaped the distribution of modern taxa. In this study twelve microchiropteran fossil assemblages from Mount Etna, central-eastern Queensland, ranging in age from more than 500,000 years to the present day, were investigated. The aim was to assess the responses of insectivorous bats to Quaternary environmental changes, including climatic fluctuations and recent anthropogenic impacts. In particular, this investigation focussed on the effects of increasing late Pleistocene aridity, the subsequent retraction of rainforest habitat, and the impact of cave mining following European settlement at Mount Etna. A thorough examination of the dental morphology of all available extant Australian bat taxa was conducted in order to identify the fossil taxa prior to their analysis in term of species richness and composition. This detailed odontological work provided new diagnostic dental characters for eighteen species and one genus. It also provided additional useful dental characters for three species and seven genera. This odontological analysis allowed the identification of fifteen fossil bat taxa from the Mount Etna deposits, all being representatives of extant bats, and included ten taxa identified to the species level (i.e., Macroderma gigas, Hipposideros semoni, Rhinolophus megaphyllus, Miniopterus schreibersii, Miniopterus australis, Scoteanax rueppellii, Chalinolobus gouldii, Chalinolobus dwyeri, Chalinolobus nigrogriseus and Vespadelus troughtoni) and five taxa identified to the generic level (i.e., Mormopterus, Taphozous, Nyctophilus, Scotorepens and Vespadelus). Palaeoecological analysis of the fossil taxa revealed that, unlike the non-volant mammal taxa, bats have remained essentially stable in terms of species diversity and community membership between the mid-Pleistocene rainforest habitat and the mesic habitat that occurs today in the region. The single major exception is Hipposideros semoni, which went locally extinct at Mount Etna. Additionally, while intensive mining operations resulted in the abandonment of at least one cave that served as a maternity roost in the recent past, the diversity of the Mount Etna bat fauna has not declined since European colonisation. The overall resilience through time of the bat species discussed herein is perhaps due to their unique ecological, behavioural, and physiological characteristics as well as their ability to fly, which have allowed them to successfully adapt to their changing environment. This study highlights the importance of palaeoecological analyses as a tool to gain an understanding of how bats have responded to environmental change in the past and provides valuable information for the conservation of threatened modern species, such as H. semoni.
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Fuller, Janice L. "Holocene forest dynamics in southern Ontario, Canada." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319318.
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Aalbersberg, Gerard. "The alluvial fringes of the Somerset Levels." Thesis, University of Exeter, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297642.
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Using core lithology and palaeoecological analyses, the vegetational and landscape development and local hydrological conditions since c. 6000 BP in two areas of the Somerset Levels has been studied. Focusing on the former characteristics of the river Brue, the floodplain upstream from Glastonbury and the area near Panborough Gap in Wedmore Ridge were investigated. In the latter area a distinct palaeochannel thought to be the prehistoric course of the Brue is present. Both areas show a similar development with saltmarsh and lagoonal environments until 6000 BP, followed by a prolonged period of Alnus - Salix carr and sedge fens. In the Panborough area freshwater deposition was interrupted by distal saltmarsh and lagoon sedimentation between 2900 BP and 2200 BP. This marine incursion caused stagnation of river discharge upstream which led to the growth of Cladium-rich "tloodinq layers" in the central raised bog area. After embankment of the rivers in the Middle Ages the changed hydrological conditions caused deposition of the upper floodplain clays. Until medieval embankment and canalisation determined its present day course, the river Brue did not have a fixed course but consisted of several small short-lived channels. The palaeochannel in the Panborough area is filled with sediment from the Sheppey while its course is inherited from a tidal channel that was incised between 2900 BP and 2200 BP. Blocked by the raised bog in the west the Brue water took a northerly drainage route, and it seems likely that it contributed to this palaeochannel system. The Brue sediment however was deposited as floodplain and backswamp clays in the Glastonbury area, and the long-held opinion that the palaeochannel is the 'Old river Brue' therefore cannot be maintained. Processes in the coastal region have been inferred from the local hydrological changes and these inferences have partly been verified with a simplified, two-dimensional hydrogeological model.
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Young, Timothy Peter. "The stratigraphy of the upper Ordovician of central Portugal." Thesis, University of Sheffield, 1985. http://etheses.whiterose.ac.uk/6043/.
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The project has involved the revision of the stratigraphy of the upper part of the Ordovician succession in central Portugal. Using evidence derived principally from the study of measured sections, with some limited geological mapping, this thesis first considers a new lithostratigraphy of the upper Ordovician deposits. The scheme presented includes four groups, twelve formations and eleven members. Most of the elements of the scheme are described here for the first time. The sedimentology of the deposits has been studied to allow an interpretation of the depositional environment. The history of sedimentation in the upper Ordovician is divided into three broad phases. In the first of these (phase A) storm-dominated deposition of detrital clastics took place on a wide, flat, shallow shelf. During the second phase (B) a localised area of igneous activity developed in the area of highest subsidence seen in the preceding phase. This igneous activity was accompanied by the deposition of some carbonate sediments. The third phase of deposition (C) is linked to the effects of the upper Ordovician glaciation. A review of most of the macrofauna recovered 1s given. The faunas of Portugal form a highly distinct and homogeneous "province" with those of Armorica, Spain, Sardinia. The palaeoecology of the faunas Montagne Noire and collected during this study are discussed. Thirteen broad associations (sensu Lockley 1983) are identified. Factors other than latitude-related influences play an important role in controlling the diversity, abundance and taxonomic constitution of the palaeocommunities. Twelve biozones are erected to cover the range of fossiliferous Ordovician strata examined in this project. The correlation between the biostratigraphie scheme erected herein and the international standard is discussed. An overview attempts to place the study area within the context of the peri-Gondwana shelf, and within the Variscan fold-belt.
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Pendred, Virginia A. "A palaeosalinity analysis of the Solent Group (Eocene-Oligocene), the Hampshire Basin, UK." Thesis, University of Portsmouth, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323282.
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Moghadam, Hossein Vaziri. "Integrated stratigraphy of the Cenomanian in the Anglo-Paris Basin." Thesis, University of Liverpool, 1999. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366304.
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Townsend, Marisia Jean. "The palaeogeography of the Lower Cretaceous Aysen Basin of southern Chile." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246282.
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Parsons, Derek Graham. "Foraminferid palaeoecology of late Cretaceous phosphogenic cycles, South West Atlas, Morocco." Thesis, University of Hull, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327836.
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Pitchford, Andrew John. "The stratigraphy, palaeontology, and palaeoecology of the Campanian Chalk of Norfolk." Thesis, University of Liverpool, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.291739.
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McKeever, Patrick J. "Studies on the sedimentology and palaeoecology of the Permian of Scotland." Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335431.
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Wimble, G. T. "The palaeoecology of the lowland coastal raised mires of South Cumbria." Thesis, Bucks New University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374830.
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Fielding, Sarah Elizabeth. "The taxonomy, taphonomy and palaeoecology of Late Jurassic testudines from Europe." Thesis, University of Portsmouth, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.490240.
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Testudine remains are exceptionally scarce in the Middle Jurassic in Western Europe. However, in the Upper Jurassic testudines are represented by two pleurodiran families, the Notoemydidae and the Platychelidae, and cryptodires: the paracryptodiran Pleurosternidae (known only from fragmentary remains from the continent and a single taxon from the Portland Limestone Formation), and the eucryptodiran families Eurysternidae and the Plesiochelyidae. The sudden appearance of these families in marine deposits of the European Upper Jurassic suggests that they constitute one of the earliest marine radiations of testudines. The work described herein is the first study of European Late Jurassic testudines that combines multiple aspects of osteology, palaeopathologies, taphonomy and functional morphology. The most significant testudine remains in terms of these aspects are from the Kimmeridgian Reuchenette Formation, Switzerland, and the Tithonian Solnhofen Limestone Formation, Germany. The synonymy of Tholemys Andrews, 1921, with Plesiochelys Rütimeyer, 1873, is refuted. Thalassemys chelonia, previously a nomen nudum, is described and figured here for the first time. A new genus and species of eurysternid unique to the British Isles is described and figured. The first record of the range and extent of palaeopathologies in Late Jurassic testudines, and a new classification scheme is provided. An experimental method using a moderately controlled and monitored outdoor environment illustrates differences between natural disarticulation and predation or scavenger attack, preferential scavenging activity and the effects of resistant integuments within a carcass. Upper Jurassic testudines are preserved in a variety of styles, reflecting different taphonomic pathways. The Kimmeridge Clay represents an attritional accumulation of testudines, whilst the accumulation of the Solnhofen Limestone Formation is a combination of attritional and catastrophic. The process which resulted in the accumulation of the Reuchenette Formation remains enigmatic. For the first time, the relationship between the length of the mantis relative to the length of the arm has been applied to Late Jurassic testudines as a method of determining habitat preference. No Late Jurassic testudines included in the analysis had forelimbs with ratios equivalent to fully terrestrial or fully marine turtles, but most appear to have been moderately adapted for the neritic (shallow to coastal marine) environment, with increased mobility and terrestrial ability when compared to extant marine turtles. These factors would probably be a selective advantage in a coastal island environment, where widespread migrations were not required, but large marine predators (e. g. Machimosaurus) were present.
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Evans, F. J. (Fiona Jocelyn). "Taxonomy, palaeoecology and palaeobiogeography of some palaeozoic fish of Southern Gondwana." Thesis, Stellenbosch : Stellenbosch University, 2005. http://hdl.handle.net/10019.1/50460.
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Thesis (PhD)--University of Stellenbosch, 2005.ENGLISH ABSTRACT: The fossiliferous Waaipoort Formation (Witteberg Group, Cape Supergroup), Ganikobis Formation (Dwyka Group, Karoo Supergroup) and Whitehill Formation (Ecca Group, Karoo Supergroup) span a protracted period interrupted by a +-45Ma glacial event. This Late Carboniferous glacial event resulted in a prolonged hiatus in sedimentation as well as significant erosion in many southern continents of Gondwana. This study demonstrates how the glacial episode affected faunal composition and changes in palaeoecology in southern Gondwana across this time period. The Waaipoort shows the highest overall faunal diversity with relatively high palaeoniscoid diversity within Ganikobis and Whitehill Formations. This study is unique in correlating Early Carboniferous - Early Permian fish fauna of South Africa and Namibia specifically, as well as other parts of southern Gondwana, and includes maps of possible fish migration routes. This study attempts to refine the body of disjointed knowledge on the taxonomy and distribution of the fish fauna surrounding this period in southern Gondwana. Three new Waaipoort taxa are recognised, and several reassigned. Earlier work on Late Carboniferous fish from Southern Africa has been updated herein to incorporate recent collections. This has allowed the recognition of up to 15 new palaeonoscoid taxa, some of which are endemic to this region. Several new taxa are recognised within the Whitehill Formation fish fauna and a new lectotype for Palaeoniscum. capensis is presented. Detailed taphonomic and sedimentological studies (with 6 lithologs) of fossil localities visited in this broad-based study verify the correlation, and impart information often lost or ignored in pure palaeontological studies on the palaeoecology or palaeoenvironment of the fauna. Systematic relationships discussed here also serve to strengthen the palaeobiogeographical correlations between the Gondwanan continents.
AFRIKAANSE OPSOMMING: Die fossie1draende Waaipoort Formasie (Witteberg Groep, Kaap Supergroep), Ganikobis Formasie (Dwyka Groep, Karoo Supergroep) en Whitehill Formasie (Ecca Groep, Karoo Supergroep) strek oor 'n uitgebreide tydvak wat 'n periode van vergletsering van ongeveer 45 miljoen jaar insluit. Hierdie Laat Karboon ystyd het sedimentasieprosesse lank onderbreek en beduidende erosie in baie van die suidelike kontinente van Gondwana veroorsaak. Die huidige studie toon hoe die vergletsering die faunistiese samestelling en veranderings in die paleo-ekologie van suidelike Gondwana beinvloed het. In totaal toon die Waaipoort die grootste faunistiese diversiteit, terwyl 'n relatief hoe diversiteit ook onder die Palaeoniscoidei van die Ganikobis en Whitehill Formasies voorkom. Hierdie studie is uniek insoverre dit spesifiek data oor die Vroee Karboon - Vroee Perm visfauna van Suid-Afrika en Namibie, asook ander gebiede van suidelike Gondwana korrelleer en kaarte van moontlike migrasieroetes insluit. Die navorsing poog om die groot hoeveelheid losstaande inligting oor die taksonomie en verspreiding van die visfauna in suidelike Gondwana te verwerk en te verfyn. Drie nuwe taksa is uit die Waaipoort geidentifiseer en 'n verdere aantal is geherklassifiseer. Vroeer navorsing oor die Laat Karboon-visse van Suider-Afrika is bygewerk in die lig van resente versamelings. Dit het die herkenning van tot 15 nuwe taksa onder die Palaeoniscoidei, waarvan sommige endemies aan hierdie streek is, moontlik gemaak. 'n Aantal nuwe taksa word onder die visfauna van die Whitehill Formasie aangeteken, saam met 'n nuwe lektotipe van Palaeoniscum capensis. Gedetailleerde tafonomiese en sedimentologiese analises van die vindplekke wat tydens hierdie studie ondersoek is en wat 6 vertikale profiele insluit, ondersteun hierdie korrelasie. Sodoende stel dit inligting beskikbaar wat dikwels gedurende suiwer paleontologiese studies oor die paleo-ekologie of paleo-omgewing van die fauna verlore sou gaan of geignoreer sou word. Die sistematiese verwantskappe wat hier bespreek word dien ook om die paleobiogeografiese ooreenkomste tussen die Gondwana-kontinente te versterk.
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Braley, Sharon Mary. "The sedimentology, palaeoecology and stratigraphy of Cretaceous rocks in N.W. Scotland." Thesis, University of Plymouth, 1990. http://hdl.handle.net/10026.1/625.
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Sediments of Cretaceous age in N.W. Scotland outcrop in small, often isolated exposures throughout the Inner Hebrides and Morvern, and have been dealt with cursorily in most previous work on the Cretaceous rocks of Britain. The aims of this study were (i)to propose a formal integrated stratigraphic scheme for the Cretaceous strata of N.W. Scotland and (ii)to model the development of the Inner Hebrides Basin (where these strata outcrop) during the Cretaceous Period. Detailed field observations, macro- and micropalaeontology (including palynology), sedimentology and structural data were integrated in an attempt to achieve these aims. Fieldwork was conducted in Morvern (Argy 11) and the Inner Hebridean islands' of lYlul], Eigg and Skye. In the proposed lithostratigraphy the Mo~ern Greensand becomes the M.orvern Greensand Formation, of which the former "Lochaline Glass Sand" or "Loch Aline White Sandstone" becomes the Lochaline White Sandstone Member. The overlying silicified chalk, outcropping in Morvern and Mull, becomes the Gribun Chalk Formation. Dark grey micritic limestone, previously undifferentiated from the silicified chalk, becomes the Strathaird Limestone Formation of which there are two clastic members: the basal Laig Gorge Sandstone IVIember and the Clach Alasdair Conglomerate lVlember. The "Upper Estua.rine Series" of Judd (1878), becomes the Beinn Iadain Mudstone Member of which there is a coarser clastic member: the Feorlin Sandstone ~ember. r]:lhese Formations comprise the Inner Hebrides Group. Biostratigraphic evidence (based primarily on dinoflagellate cysts and foraminifera) indicates a latest-Albian to IVlid-Cenomanian age for the Morvern Greensand Formation; a Late Cenomanian age for the Gribun Chalk Formation, and an Early - IVliddle Turonian age for the Str2thaird Limestone Formation. The most refined biostratigraphical range for the Beinn Iadain lVIudstone F'ormation was Albian to Palaeocene. The IVlid-Late Cretaceous development of the Inner Hebrides Basin includes two periods of major transgression, the first of which began in the latest Albian and continued through the Early Cenomanian with the deposition of the marginal clastic facies of the Morvern Greensand Formation. A minor period of regression preceded the onset of carbonate deposition in the Late Cenomanian, recorded in the Gribun Chalk Formation. A second major transgressive episode followed the silicification, uplift and erosion of the Gribun Chalk, and reflects rapid deepening of the basin during the Early to Middle Turonian, poorly sorted clastic sediments (the Laig Gorge Sandstone Member) being overlain by biomicritic limestones intercalated with debris flows (the Strathaird Limestone Formation). These two major transgressive episodes are marked by the deposition of similar lithofacies throughout N.W. Europe (although no in situ deposits of Turonian age are found in Northern Ireland). Some feature; of the Cretaceous sediments of N.W. Scotland are found elsewhere, for instance the high abundance of calcispheres and organic-rich nature of the Strathaird Limestone are typical features of the Early Turonian transgressive episode in the AngloParis Basin. However, in the Inner Hebrides Basin, these eustatic changes in sea level were imposed upon local tectonic movements as indicated Qy the weathering and erosion of the silicified Gribun Chalk prior to the deposition of the Strathaird Limestone Formation, and the debris flow events, apparently related to synsedimentary movements along the Camasunary Fault, recorded within that Formation.