3. Electronic Theses and Dissertations (ETDs) - All submissions
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Item A palaeoecological and taphonomic analysis of the micromammals from a marine isotope stage 5 layer at Klasies River, southern Cape, South Africa(2020) Maringa, NompumeleloThis research investigated the palaeoecology at Klasies River main site during Marine Isotope Stage 5d by analysing the micromammal remains excavated from the BOS Three layer in Cave 1 during the 2017 excavation season. During this time, Cave 1 was inhabited by anatomically modern humans with complex modern behaviour. The taphonomic analysis shows that light and moderate digestion on the cranials and post-cranials are common, with the majority of specimens displaying moderate breakage. These modifications are associated with Tyto alba (Barn owl) and Bubo africanus (Spotted eagle-owl) as the accumulators of the assemblage. Encrustation and soil staining are the most prevalent post-depositional modifications in both cranial and post-cranial assemblages. This relates to the presence of tufa, speleothem material and the presence of water. The taxonomic analysis on the cranial elements (mandibles, maxillae and teeth) identified the most prominent species as Otomys irroratus (Southern African vlei rat), Myosorex varius (Forest shrew) and Crocidura flavescens (Greater red musk shrew). This indicates a strong presence of taxa that prefer densely vegetated and moisture enriched environments. However, two of the dominant taxa identified also indicate a broad habitat tolerance. The Taxonomic Habitat Indices show a strong indication of closed, grassy plains with ample precipitation. The overall indication of the environment at KRM during MIS 5d is an impression of mosaic environment with bodies of standing water such as vleisItem Stratigraphy and palaeoenvironment of the Carboniferous Jurassic Karoo Supergroup in the Lebombo-Tshipise basin(2017) Clayton, Katherine EThe Karoo Supergroup represents a highly complete sedimentary succession that was deposited in several basins throughout southern Africa during the late Palaeozoic and Mesozoic (Carboniferous-Jurassic). While research in the Lebombo-Tshipise Basin of southern Africa has largely focused on lithological description of Karoo sediments or structural features of the basin, little effort has been made to describe the palaeoenvironments recorded in the sediments, or the basin fill’s response to major tectonic or climatic events. To address palaeoenvironmental reconstruction, lithostratigraphic analysis resulted in defining 11 facies associations from the Tshidize, Madzaringwe, Mikembeni, Fripp, Solitude, Elliot and Clarens Formations in the Pafuri sub-basin of the Lebombo-Tshipise Basin. Twenty boreholes drilled in Kruger National Park by the Council for Geoscience in 1979 record largely stable and consistent deposition of the Tshidize, Madzaringwe and Mikembeni Formations during the Permian. The Mikembeni Formation thins dramatically southwards, whereas the overlying Triassic successions tend to wedge out to the east. Late Triassic and Jurassic sediments directly overlie Precambrian basement in the southernmost boreholes. Significant thickness differences between the western and eastern boreholes indicate a large fault, which likely represents a rift shoulder. The palaeoenvironments in this basin are similar to those of the Main Karoo Basin, but quantitative analyses suggest a more humid environment in the Late Triassic Elliot Formation. Sauropodomorph fossils validate assignment of formerly mapped Solitude Formation as actually being the Elliot Formation. Palaeosols in the Elliot are consistent with either Oxisols or Argillisols. Wet desert conditions, evidenced by burrows produced by invertebrate communities, and tectonic activity, suggested by seismites, persist into the Early Jurassic Clarens Formation.Item The dietary behaviour of early pleistocene bovids from Cooper's Cave and Swartkrans, South Africa(2012-03-06) Steininger, Christine MarrieThere is ongoing speculation about how an increasingly arid environment contributed to the extinction of Paranthropus robustus, given that a mosaic landscape with a major part of the area consisting of predominantly open grassland environment accompanied by an escalating cooler drier climate remains the persistent palaeoecological reconstruction for this species. It has been suggested that P. robustus, a dietary specialist, was not able to adapt to an increasingly xeric habitat. This notion has been challenged by recent multi-disciplinary research on P. robustus remains, including stable light isotope and dental microwear analyses, which portray a more complex diet. Paranthropus robustus is present in a number of key fossil assemblages spanning the period ca. 1.8 to 1.0 Ma. Analysis of the stable carbon isotope composition of bioapatites and dental microwear texture analysis of different bovid taxa, associated with P. robustus remains from five discrete deposits, were used to reconstruct dietary behaviour and by inference availability of local resources. The overall pattern emerging from the bovid data indicates a more mixed and varied diet than previously thought, suggesting a heterogeneous environment, and hence a less static ecological profile for Paranthropus. The significant occurrence of mixed diets and relatively few obligate C4 grazers suggest that although C4 grasses were available in a mosaic environment, a C4-dominated ecosystem was not present. Swartkrans Member 2 (ca. 1.6 Ma) contains substantially more C3 feeders than other P. robustus deposits, signifying a vegetation community structure that was more C3-dominated than the other deposits. There is an apparent indication of shifting vegetation structure between P. robustus deposits. Thus, despite its derived craniodental morphology, P. robustus seems to have thrived through a range of climatic and ecological shifts by selecting from a variety of available foods present on the landscape.