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Analysis of 124 rounded fossils, potential bone tools, from the 2.04–1.95 Ma early hominin-bearing Drimolen Main Quarry palaeocave deposits in South Africa were subject to comparative analysis of fossil and bone collections with known taphonomic accumulator/s, actualistic experiments, and comparative analysis relative to published data in the taphonomic literature. From this sample, 51 specimens were identified as bone tools. The inclusion of these specimens raises the number of bone tools identified at Drimolen Main Quarry to 65. The bone tools have a rounded tip and an associated use-wear pattern that is restricted to, and radiates from, this rounded tip. Diaphyseal fragments were the most common raw material selected for tool use. We hypothesise that the raw material was collected from both carnivore kill and natural death sites. The striation patterns, identified though visual comparisons, present on the bone tools comprise parallel, subparallel and diagonal striations which suggests that the tools may have had a multi-use application. The place of bone technology within the South African Earlier Stone Age is also discussed. [ABSTRACT FROM AUTHOR]

Tooth growth and wear are commonly used tools for determining the age of mammals. The most speciose order of marsupials, Diprotodontia, is characterised by a pair of procumbent incisors within the lower jaw. This study examines the growth and wear of these incisors to understand their relationship with age and sex. Measurements of mandibular incisor crown and root length were made for two sister species of macropodid (kangaroos and wallabies); Macropus giganteus and Macropus fuliginosus. Histological analysis examined patterns of dentine and cementum deposition within these teeth. Broader generalisability within Diprotodontia was tested using dentally reduced Tarsipes rostratus – a species disparate in body size and incisor function to the studied macropodids. In the macropodid sample it is demonstrated that the hypsodont nature of these incisors makes measurements of their growth (root length) and wear (crown length) accurate indicators of age and sex. Model fitting finds that root growth proceeds according to a logarithmic function across the lifespan, while crown wear follows a pattern of exponential reduction for both macropodid species. Histological results find that secondary dentine deposition and cementum layering are further indicators of age. Incisor measurements are shown to correlate with age in the sample of T. rostratus. The diprotodontian incisor is a useful tool for examining chronological age and sex, both morphologically and microstructurally. This finding has implications for population ecology, palaeontology and marsupial evolution. • Analysis of incisor growth and wear in diprotodont marsupials. • Discovery that measurement of macropodid incisors informs age and sex. • Histology also finds secondary dentine and cementum inform age. • Generalisability is illustrated using dentally reduced Tarsipes rostratus. • Findings have applications in population ecology and palaeontology. [ABSTRACT FROM AUTHOR]

The Drimolen Palaeocave System in the 'Fossil Hominid Sites of South Africa' UNESCO World Heritage Site is well known for numerous remains of early hominins such as Paranthropus robustus and early Homo. These hominin fossils, along with bone tools and notably diverse accumulation of non-hominin primates and fauna, have all been excavated from the 'Main Quarry' area of the site where extensive lime-mining took place. Here we report the first radiometric age of 1.712 ± 0.269 Ma for hominin bearing deposits associated with the DNH7 Paranthropus robustus cranium in the Main Quarry area of the site, which is consistent with recent biochronological estimates. This age is similar to recent estimates for Swartkrans Member 1 Hanging Remnant (somewhere between 2.3 and 1.8 Ma) which also contains Paranthropus and early Homo. Simultaneously, we integrate the newly radiometrically dated Main Quarry deposits with a new fossil deposit, the Drimolen Makondo, discovered in 2013, that is situated some 50 m up the hill to the west from the Main Quarry. It has experienced only limited disturbance from mining but much more extensive erosion. Preliminary excavations and analysis have revealed that the Makondo infill is older than the Main Quarry, dating to 2.706 ± 0.428 Ma. Its greater age is confirmed by biochronology. The Makondo thus overlap with the suggested end of deposition of Australopithecus bearing Sterkfontein deposits, although it is yet to yield any hominin remains. These new dates for the two Drimolen Palaeocave System deposits indicates that, contrary to prior age estimates, the Drimolen site as a whole records the critical hominin and faunal turnover in South African palaeocommunities that occurred around 2.3–1.7 Ma. Finally, as the Drimolen Makondo represents a rare example of a pre-2 Ma fossil bearing deposit in the Gauteng exposures of the Malmani dolomite, we also integrate our results into the greater South African record of palaeodeposit formation (most of which occur between ∼2.0 and 1.0 Ma). An analysis of the age of palaeocave infillings across the Malmani dolomite suggests that, as is classically the case with karst, the height within the dolomite is broadly correlated to their age, although with some notable exceptions that are likely related to localised geological features. Our analysis also indicates that most caves have undergone some form of secondary karstification related to a younger phase of cave formation, contrasting with models that suggest the cavities all formed at the same time and that infill is related to erosion and the opening up of cave passages. As such, the reason that few pre-2 Ma deposits have been identified in the Gauteng exposures of the Malmani dolomite is probably because these older caves have been eroded away. Identifying such early caves is critical in understanding whether earlier hominins may have once existed in South Africa or if erosion of older deposits (or an absence of speleogenesis at this time) has made such early periods absent from the geological record. • The first radiometric age (∼ <2.0->1.4Ma) for the DNH7 Paranthropus robustus cranium. • Describes a new older fossil deposit (∼<3.1->2.3 Ma) from Drimolen. • An age for the first documented overlap of two species of Dinofelis in S. Africa. • A new model for cave formation in the Cradle of Humankind (S. Africa). • A model for understanding geological bias in the S. African hominin record. [ABSTRACT FROM AUTHOR]

Abstract The Haasgat fossil-bearing karstic system is situated within the Skurweberg Mountain range in the northeastern portion of the Fossil Hominids of South Africa UNESCO World Heritage Site in South Africa. As is the case for the nearby Gondolin hominin locality, Haasgat occurs in an area of substantial modern topographic relief that contrasts with the low-relief landscape of the southwestern extent of the World Heritage Site surrounding the Blauubank Stream Valley sites (e.g., Sterkfontein, Swartkrans, Kromdraai, Bolt's Farm). This suggests differential landscape formation processes during the Neogene and potentially novel palaeoecosystems and taphonomic processes governing karstic fossil assemblage composition across even a small geographic region. This is particularly critical given the overall paucity of taphonomic data from the region, the substantial cercopithecoid primate assemblage that is uniquely dominated by the basal baboon species Papio angusticeps, and the recent announcement of the first hominin specimen from Haasgat. Here we provide the first comprehensive taphonomic analysis of the Haasgat HGD faunal assemblage that was developed from ex situ calcified sediment blocks in the 1990s. There is direct evidence for biotic activity (e.g., large-bodied carnivores and porcupines) mediating the formation of parts of the HGD faunal assemblage, including at least part of the primate craniodental and postcranial sample. There is minimal evidence for pre-depositional element UV exposure and weathering or winnowing of the assemblage, but there is abiotic distortion and crushing of elements. Our analysis has equally found that taphonomic data from the HGD assemblage is compromised by a modern 'overprint' of damage through mechanical preparation and a lack of documentation generated during sampling, processing, and initial curation. Nearly half the cortical surfaces and many dental specimens in the assemblage exhibit evidence of substantial preparation damage rendering many purported biotic modifications ambiguous or suspect. Element proportions may be artificially skewed towards craniodental specimens and more reflective of block selection and/or selective processing rather than original deposition composition. As a result, the Haasgat HGD sample provides only limited data on the depositional processes mediating karstic assemblage formation in the region, and ultimately serves as a cautionary tale of the impacts of palaeontological sampling strategies on subsequent analysis and research. [ABSTRACT FROM AUTHOR]

Abstract: Occasional excavation of in situ and ex situ deposits at the formerly mined Gondolin paleocave system has yielded large and diverse samples of Plio-Pleistocene faunas, including isolated hominin and non-hominin primate remains. In 2003, new excavations into naturally decalcified, in situ sediments near the GD 1 datum point near the northwest corner of the cave system were undertaken. This paper describes the recovered faunal remains, taphonomy of the assemblage, and the geological and paleomagnetic context of the GD 1 deposits. The deposits represent a series of inter-stratified speleothem, in-washed sediments and talus deposits we suggest date to a time period prior to, and just after, the Olduvai normal-polarity event at around 1.7–1.8Ma. Surface sediments and clasts were introduced into the cave by rain water runoff entering a vertically-oriented entrance that had formed along a rift in the area of GD 1. The faunal assemblage consists primarily of fragmentary diaphyseal fragments and isolated teeth. Taxonomically, the small collection of specifically identifiable bovid and equid fossils is generally consistent with remains previously excavated from in situ deposits in the Gondolin paleocave system (GD 2) and dated to around 1.8Ma; however, the depositional histories of these two assemblages from Gondolin are remarkably different. The preservation and relative proportions of recovered skeletal elements at GD 1 is consistent with these materials having been initially accumulated outside the karstic system near the vertical cave entrance, and then later hydrologically sorted and deposited inside the cave. The sporadic to continuous water flow into the northwest corner of the cave system during the Pleistocene gradually decalcified the excavated fossilbearing breccias and further modified the composition and spatial distribution of the fossil assemblage by introducing potentially younger deposits and skeletal materials. This study highlights the variation in taphonomic processes that can occur within a single cave system, and the complex pre- and postdepositional geological and hydrological processes that can influence the taphonomic history of South African Plio-Pleistocene karstic fossil assemblages. [Copyright &y& Elsevier]

Abstract: Fossils of early Homo and Paranthropus have been recovered from several sites in southern Africa. Unfortunately, their precise age has historically been difficult to assess, hampering the reconstruction of their relationships to each other and to fossils from eastern Africa. Multi-dating strategies combining biochronological, archaeological, palaeomagnetic, electron spin resonance (ESR) and uranium series techniques are now clarifying their age. The following sequencing of sites is suggested: Swartkrans Member 1 (∼2.0Ma), Gondolin (∼1.8Ma), Kromdraai (1.8–1.7Ma), Sterkfontein M5A (1.8–1.4Ma), Swartkrans M2 (1.7–1.1Ma), Sterkfontein M5B (1.4–1.1Ma), Sterkfontein M5C (1.3–0.8Ma), Swartkrans M3 (∼1.0–0.6Ma). The position of Coopers D and Drimolen is difficult to access because they only have faunal age ranges (1.9–1.6Ma). ESR suggests mixing is a potential major problem in multi-generational sites. The oldest southern African representatives of early Homo and Paranthropus occur around 2.1–1.9Ma in Swartkrans Member 1 and are recorded almost continuously in the palaeocave deposits until around 1.0–0.6Ma in Swartkrans Member 3. Currently, these data suggest that Paranthropus and Homo first occur significantly later in the southern African record than the eastern African record. Moreover, Paranthropus persists much later in southern Africa than in eastern Africa. [Copyright &y& Elsevier]

South Africa contains a wealth of palaeokarst deposits that have yielded hominin fossils and Early Stone Age archaeology. Despite the complex nature of deposition within many of these caves there has been a dearth of detailed geoarchaeological studies undertaken on these sites. Many sites in South Africa have been interpreted using an overly simplistic Member System based on simplified sedimentological attributes, rather than chronostratigrahic units. Many of the defined Members thus identify different, but contemporary geological processes occurring in the caves. This has caused serious confusion in reconstructing the life histories of palaeocaves and the ages of the fossil remains interned within them. It is critical to uncover new sites that have not been extensively altered by decades of data collection and destructive mining techniques employed early in their discovery. Although unmined sites present their own problems with regards to extensive colluvium cover and access to fossil-bearing units, analysing strata that is found in-situ enhances overall confidence of interpretations drawn. A wealth of geoarchaeological and 3D visualisation techniques can now be employed to aid in the understanding of cave life histories, as well as their excavation. In this paper we present the first attempt to integrate and publish data from a range of such methods on South African fossil bearing palaeokarst using the newly discovered Drimolen Makondo deposit as a case study. This includes the use of ground penetrating radar, 3D visualisation through photogrammetry and multi-scale 3D scanning, micromophology and petrography, palaeomagnetism, mineral magnetism, synchrotron radiation, electron spin resonance, uranium-lead dating and biochronology. Our analysis has allowed us to successfully uncover the full extent of this new ∼2.61 Ma fossil bearing palaeokarst deposit and to visualise and interpret its chronostratigraphy. [ABSTRACT FROM AUTHOR]