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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Taxonomic and taphonomic interpretations of newly excavated in situ GD 2 faunal remains at Gondolin
(The Evolutionary Studies Institute, 2024-01) Engelbrecht, Micke; Val, Aurore; Kibii, Job M.; Steininger, Christine
Gondolin is one of the fossil-bearing karstic localities in the Cradle of Humankind, South Africa. Periodic excavations of calcified and decalcified sediments at several loci (GD 1,GD2 andGDA) over the last few decades have yielded a sizeable sample of Plio-Pleistocene fauna, including two hominin teeth from ex situ deposits. In 2015, renewed excavations were conducted at the GD 2 locality, which consists of decalcified in situ deposits, in order to shed more light on the site’s complex formation processes as well as to try finding new hominin material from a stratigraphically secured context. While these excavations did not yield any hominin material, abundant macrovertebrate remains were recovered. This paper presents the taxonomic composition and taphonomic characteristics of this new faunal assemblage. The occurrence of Equus sp. as well as the extinct species Metridiochoerus andrewsi and Hystrix makapanensis places the assemblage in a depositional age bracket of 2.33–1.78 Ma, which is consistent with ages already proposed forGD2. No primate material was recovered. The assemblage displays a taxonomic and bodyweight bias towards small-bodied (size classes I and II) bovids. The taphonomic characteristics of the bovid remains suggest the selective action of a leopard-like carnivore and while there is no direct evidence that the locality was used as a hyaena den, secondary scavenging by hyaenids cannot be excluded. Porcupines played an ancillary role in the bone accumulation. We performed intra- and inter-site taxonomic and taphonomic comparisons between this faunal sample and fossil assemblages from previously excavated localities at Gondolin (GD 1, GD 2 and GD A), as well as from other Paranthropus robustus-bearing sites in the Cradle of Humankind. These comparisons indicate that this new sample closely resembles the faunal assemblage previously collected from in situ calcified sediments at the GD 2 locality, in terms of species composition, bovid size class distribution, carnivore to ungulate ratio, and general taphonomic characterization.
The pre-eminence of the Karoo Basin in the knowledge of the Permo-Jurassic cynodonts: a historical synthesis and taxonomical quantification
(Evolutionary Studies Institute, 2023) Abdala, Fernando; Hendrickx, Christophe; Jasinoski, Sandra C; Gaetano, Leandro C; Liu, Jun
The search for the ancestors of mammals is historically connected with the extensive Karoo Basin of South Africa. This is because the Karoo features some of the largest exposures of Permo-Jurassic terrestrial deposits in the world and fossil discoveries were made here early in the history of palaeontology. Among the mammal-like lineages that are well-represented in Karoo fossil assemblages are the cynodonts. Originally conceived as a group exclusively containing fossil taxa, Cynodontia was subsequently redefined to include living mammals, and its Permian and early Mesozoic members are now referred to as non-mammaliaform cynodonts. Here we present a historical account of the research programme on non-mammaliaform cynodonts in the Karoo Basin, which represent the most important record of this group in the world. It covers a time spanning from the first named species in 1859 until the present day, which we arbitrarily divided into three periods: the Early Period extending from 1859 until 1932, the Second Period from 1933 to 1982, and the Current Period from 1983 until now. In the context of the global record of named species, we present quantitative analyses documenting the total number of nominal non-mammaliaform cynodont species from the Karoo (including junior synonyms and homonyms) as well as numerical comparison with taxa currently considered valid. Lastly, we compare the record of non-mammaliaform cynodont species from South Africa with other places in the world, such as Argentina and Brazil, which also have a diverse record of this group.
A new dicynodont (Anomodontia: Emydopoidea) from the terminal Permian of KwaZulu-Natal, South Africa
(Evolutionary Studies Institute, 2019-04) Kammerer, Christian F.
A new taxon of dicynodont (Thliptosaurus imperforatus gen. et sp. nov.) is described based on a dorsoventrally-crushed skull from latest Permian (upper Daptocephalus Assemblage Zone) strata in KwaZulu-Natal, South Africa. Thliptosaurus is distinguished from all other dicynodonts by an elongate intertemporal bar with broad dorsal exposure of the parietals but apparently no pineal foramen. Absence of the pineal foramen in dicynodonts is exceedingly rare; the only other taxa which exhibit this feature either have substantially broader (Kawingasaurus fossilis) or narrower (Kombuisia frerensis) intertemporal regions. Inclusion of Thliptosaurus in a phylogenetic analysis of dicynodonts recovers it as a kingoriid emydopoid, a position supported by its anteriorly-restricted pterygoid keel, elongate, curved anterior process of the lacrimal, relatively posterior position of the median pterygoid plate, and occlusion of the mandibular fenestra by a lateral plate of the dentary. Intriguingly, even in the other kingoriids which retain a pineal foramen (Dicynodontoides spp. and Kombuisia antarctica), this structure is reduced in size relative to other dicynodonts, suggesting that the pineal eye was less important for thermoregulatory activity in this clade than in other anomodonts. Although part of a local fauna including taxa that are otherwise widespread in the Karoo Basin (Daptocephalus, Lystrosaurus), the unique presence of Thliptosaurus in the relatively poorly-sampled Daptocephalus Assemblage Zone deposits of KwaZulu-Natal suggests that this region may preserve endemic taxa, and should be prioritized for future fieldwork.
Histological evidence of trauma in tusks of southern African dicynodonts
(Evolutionary Studies Institute, 2019-01) Whitney, Megan R.; Tse, Yuen Ting; Sidor, Christian A.
Dicynodonts were a clade of globally-distributed therapsids known for their abundance in the fossil record and for surviving the Permo-Triassic mass extinction. The group had distinctive dental adaptations including a beak and, in many species, paired maxillary tusks. The function of these tusks has long been of interest, yet remains poorly understood.We report here on two instances of unusual morphology in tusk dentine from specimens of: 1) Lystrosaurus from the Karoo Basin of South Africa and, 2) an unidentified dicynodontoid from the Luangwa Basin of Zambia. In both, the cross-sectional shape of the tusk root is lobed and infolded, which histological features suggest is a result of abnormal dentine deposition. We infer that this abnormal morphology is likely the consequence of trauma given its reparative nature and structural similarities to trauma-related morphologies reported in the tusks of modern elephants. This study demonstrates that histological sampling of dicynodont tusks can shed light on the biology of this important clade of therapsids.
Cranial morphology and phylogenetic analysis of Cynosaurus suppostus (Therapsida, Cynodontia) from the upper Permian of the Karoo Basin, South Africa
(Evolutionary Studies Institute, 2018-03) van den Brandt, Marc; Abdala, Fernando
Non-mammaliaform cynodonts are an important fossil lineage which include the ancestors of mammals and which illustrate the gradual evolution of mammalian characteristics. The earliest cynodonts (‘basal cynodonts’) are known from the late Permian. Cynosaurus suppostus is the second most abundant basal cynodont from the late Permian of the Karoo Basin of SouthAfrica, but is poorly studied, with the most recent description of this taxon being 50 years old. Since then, several important new specimens of this species have been collected, meriting a thorough description of its cranial anatomy and exploration of its interspecific variation. Here we present a comprehensive description of the cranial morphology of Cynosaurus suppostus, producing an updated diagnosis for the species and comparisons amongst basal cynodonts. Cynosaurus is identified by three autapomorphies amongst basal cynodonts: a subvertical mentum on the anterior lower jaw; a robust mandible with a relatively high horizontal ramus; and the broadest snout across the canine region, representing up to 31.74% of basal skull length. One of the new specimens described here preserves orbital scleral ossicles, structures rarely preserved in non-mammaliaform cynodonts. Cynosaurus is now only the third cynodont in which scleral ossicles have been reported.Anupdated phylogenetic analysis of basal cynodont interrelationships recovered Cynosaurus suppostus as a member of the Galesauridae in only two of 16 most parsimonious trees, providing poor support for its inclusion in that family. The majority of known Cynosaurus specimens were collected in a geographically restricted area approximately 150 kilometres in diameter. Most specimens have been recovered from the latest Permian Daptocephalus Assemblage Zone, with only two specimens known from the older Cistecephalus Assemblage Zone.
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.
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.
Fossil wood of Cretaceous age from the Namaqualand continental shelf, South Africa
(Bernard Price Institute for Palaeontological Research, 1994) Bamford, Marion K; Corbett, Ian B
Fossil wood was collected from sediments on the Namaqualand shelf, West Coast, South Africa, between the Orange River mouth and just to the south of Kleinzee. Forty three of these samples are here described. All the woods are gymnospermous and have abietinian tracheid pitting. Nineteen of them are well enough preserved to be identified to species level: Podocarpoxylon cf. umzambense, Mesembrioxylon cf. stokesii, M. cf. sahnii, M. cf. woburnense and Protocupressinoxylon cf. purbeckensis. The remainder of the woods have been placed in the artificial genus Mesembrioxylon without species names. The woods are probably primitive members of the Podocarpaceae growing during the Lower Cretaceous. They indicate a seasonal climate and inhabited the extensive low-lying coastal regions.
The stratigraphy of the Sterkfontein hominid deposit and its relationship to the underground cave system
(Bernard Price Institute for Palaeontological Research, 1991) Partridge, T C; Watt, I B
A programme of orientated core drilling was carried out during 1989 to elucidate stratigraphic relationships within the Sterkfontein Formation and to obtain a representative suite of samples for palaeomagnetic analysis. The cores have revealed that the hominid-bearing cave deposits occur as a continuous succession comprising 6 Members and extending to a maximum depth of about 30 m below present surface. Of these Member I (comprising a sterile, residual fill) and Member 3 are the most extensive. This sequence has been displaced vertically downwards within a zone of decalcification coinciding with the central part of the deposit. This zone has been the focus of recent deep excavations at the site. The results of the drilling, in conjunction with recent surveys of the underground cave system, confirm that a dolomite floor existed at an average depth of about 20 m at the time offirst cave filling. Subsequent cavern development down to depths in excess of 50 m caused the local collapse of some lower units of the Sterkfontein Formation and, as new openings developed to the surface, permitted the ingress of younger fills below the base of the hominid-bearing succession.
Palaeo-ecology of the Sterkfontein hominids: a review and synthesis
(Bernard Price Institute for Palaeontological Research, 1991) McKee, Jeffrey K
Excavations at the Sterkfontein hominid fossil site have yielded a rich and revealing faunal assemblage. Evolutionary transitions are evident in early hominids and associated fauna between the times represented by Members 4 and 5. Member 4 has yielded a large and variable sample of Australopithecus africanus as well as evidence of considerable species diversity among the artiodactyls, carnivores and primates. The appearance of early Homo along with stone and bone tools in Member 5 coincides with a reduction of species representation in the orders of larger mammals as well as with the occurrence of new derived species and apparent extinctions. Three hypotheses have been suggested to account for the trends seen in the hominid-bearing members of the Sterkfontein Formation. The 'Climatic Change Hypothesis' accounts for the evolutionary trends by the causal factors of global and local cooling and aridification with evidence of savanna-grasslands supplanting an earlier environment with a denser cover of vegetation. The 'Taphonomic Hypothesis' explains changes in relative species representation at Sterkfontein in terms of the bone-accumulating agents; in Member 4 primary carnivores were largely responsible for the deposition of large mammalian fauna, whereas the scavenging activities of early Homo would have accounted for much of the bone and all of the artefacts found in Member 5. A third proposition is the 'Species Interaction Hypothesis', a derivative of the ' Red-Queen Hypothesis'; here the dynamics of species interaction, including competition and commensalism among hominids, carnivores and cercopithecids, propel the evolutionary changes and cause the extinctions. These hypotheses are not mutually exclusive, but the relative effects of the factors involved must be verified or refuted with better chronological controls and further analyses of the African fossil sites. The Sterkfontein Formation represents a microcosm in which various scenarios of African mammalian evolution can be tested.

Palaeontologia africana

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