The current model for the end-Permian terrestrial ecosystem crisis holds that systematic loss exhibited by an abrupt turnover from the Daptocephalus to the Lystrosaurus Assemblage Zone (AZ; Karoo Basin, South Africa) is time equivalent with the marine Permian-Triassic boundary (PTB). The marine event began at 251.941 ± 0.037 Ma, with the PTB placed at 251.902 ± 0.024 Ma (2σ). Radio-isotopic dates over this interval in the Karoo Basin were limited to one high resolution ash-fall deposit in the upper Daptocephalus AZ (253.48 ± 0.15 (2σ) Ma) with no similar age constraints for the overlying biozone. Here, we present the first U-Pb CA-ID-TIMS zircon age (252.24 ± 0.11 (2σ) Ma) from a pristine ash-fall deposit in the Karoo Lystrosaurus AZ. This date confirms that the lower exposures of the Lystrosaurus AZ are of latest Permian age and that the purported turnover in the basin preceded the end-Permian marine event by over 300 ka, thus refuting the previously used stratigraphic marker for terrestrial end-Permian extinction.
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http://dx.doi.org/10.1038/s41467-020-15243-7 | DOI Listing |
Sci Rep
October 2024
Department of Geology, University of the Free State, Bloemfontein, 9300, South Africa.
The Main Karoo Basin in South Africa is a typical example of an expanding arid region dependent on groundwater resources. Dolerite dikes in the region, analogous to dolerite dikes worldwide, are known to influence subsurface groundwater flow and spatially relate to high-yielding boreholes. Here, the effect of dolerite dikes on groundwater flow is remotely assessed using the Modified Soil Adjusted Vegetation Index derived from high-resolution multi-spectral satellite imagery.
View Article and Find Full Text PDFPLoS One
September 2024
Evolutionary Studies Institute and School of Geosciences, University of the Witwatersrand, Johannesburg, South Africa.
The Horned Serpent panel at La Belle France (Free State Province, South Africa) was painted by the San at least two hundred years ago. It pictures, among many other elements, a tusked animal with a head that resembles that of a dicynodont, the fossils of which are abundant and conspicuous in the Karoo Basin. This picture also seemingly relates to a local San myth about large animals that once roamed southern Africa and are now extinct.
View Article and Find Full Text PDFPeerJ
August 2024
Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, Gauteng, South Africa.
Therocephalia are an important clade of non-mammalian therapsids that evolved a diverse array of morphotypes and body sizes throughout their evolutionary history. The postcranial anatomy of therocephalians has largely been overlooked, but remains important towards understanding aspects of their palaeobiology and phylogenetic relationships. Here, we provide the first postcranial description of the large akidnognathid eutherocephalian by examining multiple specimens from fossil collections in South Africa.
View Article and Find Full Text PDFProc Biol Sci
July 2024
Department of Biological Sciences, University of Cape Town, Cape Town 7700, South Africa.
PeerJ
October 2023
Department of Geological Sciences, University of Cape Town, Cape Town, South Africa.
Using modern ichnological and stratigraphic tools, we reinvestigate two iconic sauropodomorph-attributed tetradactyl ichnogenera, and , and their stratigraphic occurrences in the middle Upper Triassic of Lesotho. These tracks have been reaffirmed and are stratigraphically well-constrained to the lower Elliot Formation (Stormberg Group, Karoo Basin) with a maximum depositional age range of <219-209 Ma (Norian). This represents the earliest record of basal sauropodomorph trackways in Gondwana, if not globally.
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