Wits Evolutionary Studies Institute (ESI)

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    Discovering Hominins - Application of Medical Computed Tomography (CT) to Fossil-Bearing Rocks from the Site of Malapa, South Africa.
    (Public Library of Science, 2015-12-18) Smilg, J.S.; Berger, L.R.; Smilg, Jacqueline S.
    In the South African context, computed tomography (CT) has been used applied to individually prepared fossils and small rocks containing fossils, but has not been utilized on large breccia blocks as a means of discovering fossils, and particularly fossil hominins. Previous attempts at CT imaging of rocks from other South African sites for this purpose yielded disappointing results. For this study, 109 fossil- bearing rocks from the site of Malapa, South Africa were scanned with medical CT prior to manual preparation. The resultant images were assessed for accuracy of fossil identification and characterization against the standard of manual preparation. The accurate identification of fossils, including those of early hominins, that were not visible on the surface of individual blocks, is shown to be possible. The discovery of unexpected fossils is reduced, thus lowering the potential that fossils could be damaged through accidental encounter during routine preparation, or even entirely missed. This study should significantly change the way fossil discovery, recovery and preparation is done in the South African context and has potential for application in other palaeontological situations. Medical CT imaging is shown to be reliable, readily available, cost effective and accurate in finding fossils within matrix conglomerates. Improvements in CT equipment and in CT image quality are such that medical CT is now a viable imaging modality for this palaeontological application.
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    Comparison of Holocene temperature data (Boomplaas Cave) and oxygen isotope data (Cango Caves)
    (Academy of Science of South Africa (ASSAf), 2016-05) Thackeray, J.F.
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    An Acheulean handaxe from Gladysvale Cave site, Gauteng, South Africa.
    (Academy of Science of South Africa (ASSAf), 2006-03) Hall, G.; Pickering, R.; Lacruz, R.; Hancox, J.; Berger, L.R.; Schmid, P.
    WE DESCRIBE A SINGLE HANDAXE FROM fossiliferous breccias at Gladysvale Cave, South Africa. The artefact is the only known tool so far discovered during the controlled excavations conducted at this site over the last decade, and was recovered from decalcified sediments near the stratigraphic interface of two breccia units, making it difficult to assign it with confidence to either. The morphology of the handaxe indicates a middle-late Acheulean industry, and preliminary electron spin resonance and palaeomagnetic dating suggest an age of greater than 780 000 years.
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    Carnivoran remains from the Malapa hominin site, South Africa.
    (Public Library of Science, 2011-11-03) Kuhn, B.F.; Werdelin, L.; Hartstone-Rose, A.; Lacruz, R.S.; Berger, L.R.
    Recent discoveries at the new hominin-bearing deposits of Malapa, South Africa, have yielded a rich faunal assemblage associated with the newly described hominin taxon Australopithecus sediba. Dating of this deposit using U-Pb and palaeomagnetic methods has provided an age of 1.977 Ma, being one of the most accurately dated, time constrained deposits in the Plio-Pleistocene of southern Africa. To date, 81 carnivoran specimens have been identified at this site including members of the families Canidae, Viverridae, Herpestidae, Hyaenidae and Felidae. Of note is the presence of the extinct taxon Dinofelis cf. D. barlowi that may represent the last appearance date for this species. Extant large carnivores are represented by specimens of leopard (Panthera pardus) and brown hyaena (Parahyaena brunnea). Smaller carnivores are also represented, and include the genera Atilax and Genetta, as well as Vulpes cf. V. chama. Malapa may also represent the first appearance date for Felis nigripes (Black-footed cat). The geochronological age of Malapa and the associated hominin taxa and carnivoran remains provide a window of research into mammalian evolution during a relatively unknown period in South Africa and elsewhere. In particular, the fauna represented at Malapa has the potential to elucidate aspects of the evolution of Dinofelis and may help resolve competing hypotheses about faunal exchange between East and Southern Africa during the late Pliocene or early Pleistocene.
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    Taphonomic analysis of the faunal assemblage associated with the hominins (Australopithecus sediba) from the early pleistocene cave deposits of Malapa, South Africa.
    (Public Library of Science, 2015-06-10) Val, A.; Dirks, P.H.G.M.; Backwell, L.R.; Berger, L.R.; D'Errico, F.
    Here we present the results of a taphonomic study of the faunal assemblage associated with the hominin fossils (Australopithecus sediba) from the Malapa site. Results include estimation of body part representation, mortality profiles, type of fragmentation, identification of breakage patterns, and microscopic analysis of bone surfaces. The diversity of the faunal spectrum, presence of animals with climbing proclivities, abundance of complete and/or articulated specimens, occurrence of antimeric sets of elements, and lack of carnivore-modified bones, indicate that animals accumulated via a natural death trap leading to an area of the cave system with no access to mammalian scavengers. The co-occurrence of well preserved fossils, carnivore coprolites, deciduous teeth of brown hyaena, and some highly fragmented and poorly preserved remains supports the hypothesis of a mixing of sediments coming from distinct chambers, which collected at the bottom of the cave system through the action of periodic water flow. This combination of taphonomic features explains the remarkable state of preservation of the hominin fossils as well as some of the associated faunal material.
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    Papio cranium from the hominin-bearing site of Malapa: Implications for the evolution of modern baboon cranial morphology and South African Plio-Pleistocene biochronology.
    (Public Library of Science, 2015-08-19) Gilbert, C.C.; Steininger, C.M.; Kibii, J.M.; Berger, L.R.
    A new partial cranium (UW 88-886) of the Plio-Pleistocene baboon Papio angusticeps from Malapa is identified, described and discussed. UW 88-886 represents the only non-hominin primate yet recovered from Malapa and is important both in the context of baboon evolution as well as South African hominin site biochronology. The new specimen may represent the first appearance of modern baboon anatomy and coincides almost perfectly with molecular divergence date estimates for the origin of the modern P. hamadryas radiation. The fact that the Malapa specimen is dated between ~2.026–2.36 million years ago (Ma) also has implications for the biochronology of other South African Plio-Pleistocene sites where P. angusticeps is found.
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    Superior cervical vertebrae of a Miocene hominoid and a Plio-Pleistocene hominid from southern Africa
    (Bernard Price Institute for Palaeontological Research, 2000) Gommery, Dominique
    The Miocene hominoid and Plio-Pleistocene hominid vertebral record is poor. In 1994, a complete atlas of a hominoid was found in breccia at Berg Aukas in Namibia. Its age was estimated to be middle Miocene (13 myr) on the basis of microfauna. This locality yielded the holotype of Otavipithecus namibiensis and the atlas could belong to the same genus. The specimen exhibits clear hominoid traits such as a weakly salient retroglenoid tubercle at the superior articular facet of the lateral mass, and a horizontal transverse process. This morphology of the transverse process is close to that of pygmy chimpanzees, gibbons and African colobines, suggesting that Otavipithecus was arboreal. This confirms the conclusions drawn from other parts of the skeleton. From the size of the atlas, a body weight of 15-20 kg is estimated for the Berg Aukas hominoid, which accords with previous estimates based on its teeth. The second fossil considered in this paper is an axis from Swartkrans, SK 854, dated to nearly 1,8 myr. This axis is compared with another Plio-Pleistocene axis from Ethiopia, AL 333.101. SK 854 shows a morphology different from that of humans and AL 333.101, and also of apes. The South African axis was attributed to Paranthropus by Robinson (1972), and its morphology is probably typical of bipedalism associated with climbing.
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    New evidence of the Giant Hyaena, Pachycrocuta brevirostris (Carnivora, Hyaenidae), from the Gladysvale Cave deposit (Plio-pleistocene, John Nash Nature Reserve, Gauteng, South Africa)
    (Bernard Price Institute for Palaeontological Research, 2001) Mutter, Raoul J; Berger, Lee R; Schmid, Peter
    A well preserved cranium which represents the most complete skull of Pachycrocuta brevirostris (Carnivora, Hyaenidae) discovered in Africa, and a maxillary fragment from the Gladysvale Cave Deposit (John Nash Nature Reserve, Gauteng, South Africa) are described and compared to other fossil and extant hyaenid specimens from South Africa and Europe. In addition, some aspects of functional morphology in the hyaenid dentition are reconsidered and suggested to be directly related to the palaeoecological role of P. brevirostris.
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    A problematical element in the Glossopteris flora of Vereeniging
    (Bernard Price Institute for Palaeontological Research, 1975) LeRoux, S F
    An unusual element, not previously recorded from the mixed Glossopteris Flora of Vereeniging, is described here. The type material was obtained from a rich fossiliferous zone, previously described by the author (Le Roux, 1963, pp. 1-2). The material available for study consists of a single specimen of an incomplete frond preserved in the form of an impression in fine-grained laminated clay.
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    The morphology and relationships of Youngina capensis Broom and Prolacerta broomi Parrington
    (Bernard Price Institute for Palaeontological Research, 1975) Gow, Chris E
    Comprehensive descriptions of the osteology of Youngina capensis Broom and Prolacerta broomi Parrington are presented. New details of the braincase of Proterosuchus fergusi Broom are given as these became necessary for comparative purposes. It is suggested that the initial radiation of sauropsid reptiles was a Permian event as yet poorly documented. The phylogenetic position of Youngina forward and backward in time cannot be narrowly defined, though certain characters seem specifically to preclude it from lizard ancestry. Prolacerta, on the basis of tooth implantation, braincase morphology and postcranial anatomy is shown to be closest to the proterosuchian thecodonts. It is very definitely not concerned with lizard origins, but would on available evidence seem to be a perfectly good ancestor for the middle Triassic forms Macrocnemus and Tanystropheus which latter must cease to be regarded as lizard ancestors. We have here a rather distinct reptilian lineage which branched off from common ancestral stock just prior to the advent of archosaurs.