Volume 52 2017–2018

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https://wiredspace.wits.ac.za/handle/10539/23007

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Browsing Volume 52 2017–2018 by Author "Cawthra, Hayley C."

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    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.
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    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.