Palaeontologia africana
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ISSN (print): 0078-8554
ISSN (electronic): 2410-4418
For queries regarding content of Palaeontologia africana collections please contact Jonah Choiniere by email : jonah.choiniere@wits.ac.za or Tel : 011 717 6684
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Browsing Palaeontologia africana by Keyword "aeolianites"
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Item Biofilm assists recognition of avian trackways in Late Pleistocene coastal aeolianites, South Africa(Evolutionary Studies Institute, 2017-12) Helm, Charles W.; Anderson, Robert J.; Buckley, Lisa G.; Cawthra, Hayley C.; de Vynck, Jan C.Fourteen fossil avian tracksites have been identified in Late Pleistocene aeolianite deposits on the Cape south coast of SouthAfrica. One of these sites is unusual because of the preferential adherence of organic material (biofilm) to the natural cast tracks. This has enabled the recognition and identification of two ~6 m long, approximately parallel trackways that would otherwise not have been noticed. The trackways are visible from a distance of over 100 metres and contain 20 and 14 individual tracks, respectively. Up to 50 avian tracks are evident at this site. As the biofilm layer continues to thicken, the trackways become increasingly visible. Avian trackways of this length are globally rare.We propose that the biofilm adheres to sections with higher relief on a sedimentary surface, and that an understanding of this mode of preservation can be useful to more easily identify trackways in areas of comparable geological setting.Item Hominin tracks in southern Africa: a review and an approach to identification(Evolutionary Studies Institute, 2019-01) Helm, Charles W.; Lockley, Martin G.; Cole, Kevin; Noakes, Timothy D.; McCrea, Richard T.Three Late Pleistocene hominin tracksites have been reported from coastal aelioanites in South Africa. Two have been dated to 124 ka and 117 ka , and the third is inferred to be 90 ka. There are no other globally reported sites for probable Homo sapiens tracks older than 46 ka. Given this documented record, a search for further hominin tracksites in southern Africa may well yield additional positive results. However, this is a field that demands scientific rigour, as false positive tracksites (pseudotracks) may occur. Criteria have been developed for the identification of fossil vertebrate tracks and hominin tracks, but these are specific neither to southern Africa nor to aeolianites.An important caveat is that the tracks of shod humans would not fulfil these criteria. Preservation of tracks varies with facies and is known to be suboptimal in aeolianites. An analysis of the tracks from the three documented South African sites, along with pseudotracks and tracks of questionable provenance, allows for the proposal and development of guidelines for fossil hominin track identification that are of specific relevance to southern Africa. Such guidelines have broader implications for understanding the constraints that track preservation and substrate have on identifying diagnostic morphological features.Item Late Pleistocene vertebrate trace fossils in the Goukamma Nature Reserve, Cape South Coast, South Africa(Evolutionary Studies Institute, 2018-02) Helm, Charles W.; McCrea, Richard T.; Lockley, Martin G.; Cawthra, Hayley C.; Thesen, Guy H. H.; Mwankunda, Joshua M.More than 100 Late Pleistocene trace fossil sites have been identified in aeolianites along a 275 kilometer stretch of the Cape south coast. A zone of concentration of such sites exists within the Goukamma Nature Reserve, both along the coast and along the Goukamma River. These sites provide insight into the Pleistocene fauna along the Cape south coast. Features include lion trackways, multiple elephant tracksites, a long trackway most likely attributable to Long-horned Buffalo, medium-sized carnivore tracks, avian tracks, equid tracks attributable to the giant Cape horse, numerous artiodactyl tracks, and burrow traces. The ephemeral nature of the tracksites makes regular surveys of these areas desirable, along with site documentation and trackway replication and preservation initiatives. The protected status of the area offers opportunities for geoheritage appreciation.Item Late Pleistocene vertebrate trace fossils of the Walker Bay Nature Reserve(The Evolutionary Studies Institute, 2024-12) Helm, Charles W.; Carr, Andrew S.; Cawthra, Hayley C.; De Vynck, Jan C.In the Walker Bay Nature Reserve, on South Africa’s Cape southwest coast, a suite of 25 Pleistocene ichnosites has been identified in aeolianite deposits. Dating from one site using optically stimulated luminescence indicates an age of 76 ± 5 ka. Highlights, indicating the global importance of the reserve, include a possible hominin tracksite and the first reported occurrence of fossil snake traces and tortoise tracks. The ichnological findings can be correlated with the substantial archaeological record from the nearby DieKelders Cave. Elephant tracks are reported from several sites, but are not present in the archaeological record, whereas the plentiful occurrence of burrow traces of appropriate size corroborates the body fossil record from archaeological deposits, in which the Cape dune molerat predominates. The protected nature of the region allows for opportunities for conservation and education. Photogrammetry represents a non-invasive means of preserving and replicating the ichnological findings.Item Pleistocene vertebrate trace fossils of Robberg Nature Reserve(Evolutionary Studies Institute, 2019-12) Helm, Charles W.; Cawthra, Hayley C.; Hattingh, Rudolph; Hattingh, Sinèad; McCrea, Richard T.; Thesen, Guy H. H.More than 140 Late Pleistocene trace fossil sites have been identified in aeolianites and lithified foreshore deposits along a 350 kilometre stretch of the Cape south coast in South Africa. Robberg Nature Reserve lies within this area and contains a zone of concentration of such tracksites, which complement the Pleistocene vertebrate body fossil record and assist in shedding light on the palaeoenvironment and palaeoecology of the Palaeo-Agulhas Plain. Ichnofossil sites unique to or of special significance within Robberg Nature Reserve include a substantial palaeosurface exposure that allows an estimate of track density, the best-preserved rhinoceros trackway identified to date, very well preserved artiodactyl tracks in the formof natural casts, small equid tracks, large elephant transmitted tracks, and well preserved sub-surface golden mole burrows with a burrow chamber. Aeolianite layers at Robberg have recently been dated to Marine Isotope Stage (MIS) 3. Samples that we have obtained for dating from the main palaeosurface underlie these dated layers and are anticipated to contribute to the understanding of the Pleistocene geology of the Robberg Peninsula. The protected status of the area lends itself to conservation, replication, interpretation and education initiatives.