Sibudu Cave, KwaZulu-Natal: Background to the excavations of Middle Stone Age and Iron Age occupations

Sibudu Cave excavations have yielded an Iron Age occupation directly overlying a long sequence of final Middle Stone Age (MSA) layers dating c. 61 000-26 000 years ago. Older, undated layers contain a Howiesons Poort Industry. A diverse animal population is represented in the final MSA. Proxy environmental data suggest cooler, drier conditions with a larger savanna component to the vegetation than at present

Southern African arrow poison recipes, their ingredients and implications for Stone Age archaeology

Abstract: Biochemical analyses of residues preserved on ethno-historical and archaeological artefacts increase our understanding of past indigenous knowledge systems. The interpretation of biochemical traces is, however, difficult. Problems that can hamper credible interpretations of ethno-historical or archaeological residues include incomplete knowledge about local natural products, limited published data about product applications, and overestimation of the abilities of the analytical techniques to make specific identifications. In an initial attempt to address some of the challenges, we discuss arrow poison as a case in point, and we provide complete, updated inventories of known southern African poison ingredients and recipes, suspected poisons, and the current state of knowledge about these toxins and their effects. We also suggest that discoveries of ancient arrow poison, and the technical steps involved in early toxicology, have the potential to indicate levels of human cognition

Underground transfer of carbonised organic residues to lithics during preliminary fire experiments: implications for archaeology

Using fire experiments, we investigate claims that black organic residues on lithics found in Stone Age sites are markers for heat treatment of rocks in the embers of aboveground wood fires. We buried sedges overlain with lithics and bone to replicate plant bedding sometimes found in archaeological sites. Small fires were lit over the material buried under a mixture of coarse- and medium-grained sand. Black carbonised residues formed on several lithics that were in direct contact with buried sedges that burned below the fire. FTIR, Raman and preliminary GC-MS measurements were made on dried and burnt sedge, burnt bone, and on a prominent black residue that formed on one quartz piece that had been in contact with buried fresh sedge when it was heated. Importantly, we were able to confirm the spontaneous and accidental transfer of organic compounds to lithics buried and heated underground in the presence of plant material. This means that carbonised organic residues are not useful markers for determining whether heat treatment of rocks took place above or below ground. Our preliminary experiments imply that further work should be done to investigate the causes of the residues formed on lithics underground

Past environmental proxies from the Middle Stone Age at Sibudu, Kwazulu-Natal, South Africa

Middle Stone Age technological and behavioural developments in southern Africa are central to understanding the emergence of modern humans, and elucidating the role of environmental change in this trajectory is dependent on emerging palaeoclimatic reconstructions. Climate proxies from Middle Stone Age sites are often poorly preserved, coarsely resolved or subject to anthropogenic selection and are not considered in favour of global environmental proxies despite the fact that the modern climate regimes at the relevant archaeological sites differ profoundly. Sibudu has a well-preserved Middle Stone Age sequence that has yielded abundant palaeoclimate proxy data. Isotopic analysis of charcoal, charcoal anatomy and species representation, macro- and micro-faunal remains, sediment texture, mineralogy and magnetic susceptibility, pollen and macrobotanical remains provide evidence for the environmental succession specific to this site. The isotopic data suggest that archaeological charcoal was not significantly post-depositionally altered. During the Howiesons Poort (65–62 ka) the local environment was thickly forested, moist and more humid than during the 58 ka occupations. The environment changes during the post-Howiesons Poort occupation (~58 ka) into the late MSA occupation (~48 ka); conditions became drier and colder than present with vegetation shifting to open savanna grassland or woodlands.Les évolutions technologiques et comportementales du Middle Stone Age dans le sud de l’Afrique sont essentielles pour comprendre l’émergence de l’Homme moderne, et la compréhension du rôle des changements environnementaux dans cette trajectoire dépend des reconstitutions paléo-climatiques émergentes. Les données indirectes liées au climat du MSA sont souvent mal conservées, de résolution grossière ou soumis à une sélection d’origine anthropique et sont abandonnées au profit des données indirectes liées aux conditions environnementales globales, en dépit du fait que les régimes climatiques modernes sur les sites archéologiques étudiés diffèrent profondément. Sibudu a une séquence bien conservée du Middle Stone Age qui a fournit d’abondantes données paléoclimatiques indirectes. L’analyse isotopique de charbons de bois, l’anatomie du charbon de bois et la représentation des espèces, des restes de faunes macroscopiques et microscopiques, la texture des sédiments, la minéralogie et la susceptibilité magnétique, le pollen et les restes macrobotaniques fournissent des indices de l’évolution de l’environnement spécifique à ce site. Au cours de la période Howiesons Poort (65–62 ka), l’environnement local est couvert de forêts épaisses et humide, plus humide encore lors des occupations de 58 ka. L’environnement change au cours de l’occupation post-Howiesons Poort (~ 58 ka) jusqu’a la fin de l’occupation MSA (~ 48 ka) : il devient plus sec et plus froid qu’à présent et la végétation se mue en grande savane herbeuse ou boisée.Palaeo-Anthropological Scientific Trust (PAST), the National Research Foundation (NRF), the Council for Scientific and Industrial Research (CSIR) and the University of the Witwatersrand.http://www.african-archaeology.dehb201

Infrared reflectance spectroscopy as an analytical technique for the study of residues on stone tools : potential and challenges

FTIR (Fourier transform infrared) spectroscopy is a non-destructive analytical method that has been used successfully to analyse both inorganic and organic archaeological material. Using a microscope attachment has the additional benefit of analysing very small spots (diameter 100 mm) directly on an artefact without sample preparation or destruction. It is therefore a suitable method to study residues on prehistoric stone tools. However, using a microscope without an ATR (attenuated total reflection) microscope objective, results in a combination of reflection and transmission/absorbance FTIR spectra, which is not always as easy to interpret as directly measured transmission/absorbance spectra. In order to improve the interpretation of spectra recorded on archaeological samples, the method was tested with replicated Middle Stone Age stone points used during hunting and butchery experiments on parts of a blue wildebeest (Connochaetes taurinus) published in 2004 (Lombard et al., 2004). In this case, the residues on the tools were known and post-depositional contamination was eliminated. Additional samples of the organic materials, and the minerals from which the tools were made were also available. Therefore, we could assess the viability of FTIR reflectance spectra for distinguishing between bone, fat and protein residues.NRF, the Universities of Pretoria, the Witwatersrand and Johannesburghttp://www.elsevier.com/locate/jashb2014ai201

Potential for identifying plant-based toxins on San hunter-gatherer arrowheads

The antiquity of the use of hunting poisons has received much attention in recent years. In this paper we present the results of a pilot study designed to detect the presence of organic compounds, typically of less than 1200 Da, from poisonous plants that may have been used as hunting poisons in the past. We used ultra-performance liquid chromatography connected to a Synapt G2 high-resolution MS-QTOF mass spectrometer (UPLC-QTOF-MS) to provisionally identify plant-based toxins present in (1) extracts of fresh plant material, (2) a blind control recipe consisting of three plant ingredients and (3) a Hei||om arrow poison of unknown ingredients. Although not all expected toxic compounds were identified, those that were identified compared favourably with those reported in the literature and confirmed through databases, specifically the Dictionary of Natural Products and ChemSpider. MS/MS fragmentation patterns and accurate mass were used for tentative identification of compounds because archaeological residues usually contain insufficient material for unambiguous identification using nuclear magnetic resonance. We highlight the potential of this method for accurately identifying plant-based toxins present on archaeological artefacts and unique (albeit non-toxic) chemical markers that may allow one to infer the presence of toxic plant ingredients in arrow poisons. Any chemical study of archaeological material should consider the unique environmental degradative factors and be sensitive to the oxidative by-products of toxic compounds

Technological and functional analysis of 80–60 ka bone wedges from Sibudu (KwaZulu-Natal, South Africa)

Fully shaped, morphologically standardized bone tools are generally considered reliable indicators of the emergence of modern behavior. We report the discovery of 23 double-beveled bone tools from ~ 80,000–60,000-year-old archaeological layers at Sibudu Cave in KwaZulu-Natal, South Africa. We analyzed the texture of use-wear on the archaeological bone tools, and on bone tool replicas experimentally used in debarking trees, processing rabbit pelts with and without an ochre compound, digging in sediment in and outside a cave, and on ethnographic artefacts. Debarking trees and digging in humus-rich soil produce use-wear patterns closely matching those observed on most Sibudu tools. This tool type is associated with three different Middle Stone Age cultural traditions at Sibudu that span 20,000 years, yet they are absent at contemporaneous sites. Our results support a scenario in which some southern African early modern human groups developed and locally maintained specific, highly standardized cultural traits while sharing others at a sub-continental scale. We demonstrate that technological and texture analyses are effective means by which to infer past behaviors and assess the significance of prehistoric cultural innovations.publishedVersio

Technological and functional analysis of 80–60 ka bone wedges from Sibudu (KwaZulu-Natal, South Africa)

Fully shaped, morphologically standardized bone tools are generally considered reliable indicators of the emergence of modern behavior. We report the discovery of 23 double-beveled bone tools from ~ 80,000–60,000-year-old archaeological layers at Sibudu Cave in KwaZulu-Natal, South Africa. We analyzed the texture of use-wear on the archaeological bone tools, and on bone tool replicas experimentally used in debarking trees, processing rabbit pelts with and without an ochre compound, digging in sediment in and outside a cave, and on ethnographic artefacts. Debarking trees and digging in humus-rich soil produce use-wear patterns closely matching those observed on most Sibudu tools. This tool type is associated with three different Middle Stone Age cultural traditions at Sibudu that span 20,000 years, yet they are absent at contemporaneous sites. Our results support a scenario in which some southern African early modern human groups developed and locally maintained specific, highly standardized cultural traits while sharing others at a sub-continental scale. We demonstrate that technological and texture analyses are effective means by which to infer past behaviors and assess the significance of prehistoric cultural innovations

Human deciduous teeth from the Middle Stone Age layers of Sibudu Cave (South Africa)

Abstract: In the African Pleistocene, the fossil evidence for early Homo sapiens populations is still relatively limited. Here we present two additional specimens (two deciduous teeth) recovered from the Middle Stone Age (MSA) deposits of Sibudu Cave (KwaZulu‐Natal, South Africa). We describe their morphology and metrics, using three‐dimensional models of the teeth obtained from high‐resolution micro‐CT images. The first specimen is a Ldm1 (HUM. TO 1) recovered in the BS5 layer dated 77.3 ± 2.7 ka, and associated with stone tools assigned to the “pre‐Still Bay” assemblage. The other specimen is a Rdi1 (HUM. TO 2) coming from the Pinkish Grey Sand (PGS) layer, dated 64.7±2.3 ka, and associated with a Howieson’s Poort industry. Both teeth are well preserved, with minor post mortem cracks not affecting the overall morphology, and they comprise the intact, worn crown and the remnants of the roots, naturally resorbed. A large carious lesion occupies most of the distal face and part of the occlusal surface in the Ldm1; also a chip of enamel is missing from the disto‐buccal corner. In the Rdi1 average enamel thickness and relative enamel thickness values have been measured. For both teeth, we compared mesiodistal (MD) and bucco‐lingual (BL) diameters with those of other Late Pleistocene deciduous teeth and extant Homo sapiens. The analysis has shown that the teeth are comparable in size with the other MSA specimens described in the literature

Plants, people and fire: Phytolith and FTIR analyses of the post-Howiesons Poort occupations at Border Cave (KwaZulu-Natal, South Africa)

Border Cave is a well-known South African Middle and Early Later Stone Age site located in KwaZulu-Natal. The site has exceptional plant preservation, unparalleled in the African Middle Stone Age archaeological record. This study focuses on the phytolith and FTIR analysis of two Members (2 BS and 2 WA) of the under-documented post-Howiesons Poort occupations dating to ∼60 ka. These members contain complex successions of vertically overlapping, interdigitating light brown sediments, plant bedding and combustion features of various sizes. The complexity and distinctiveness of these deposits provide an excellent opportunity for the study of plant exploitation strategies and their associated human behaviour. Our taphonomic assessment inferred, through the variability of phytolith properties and minerals composing archaeological layers, that specific occupations suffered more physical weathering than others, for example in the form of trampling. The preservation of fragile and highly soluble phytoliths (eudicot leaf phytoliths) and the high frequencies of articulated phytoliths indicates that some bedding deposits experienced little disturbance after their deposition. Not all bedding layers dating to ⁓60 ka show, from a phytolith perspective, the same plant composition, which could be explained in terms of changes in human preference for the use of plants over time to construct bedding or because distinct types of living floors are represented. Finally, the systematic application of phytoliths and FTIR to the complex archaeological sequence of Border Cave confirm these analyses can be used in the future to identify bedding deposits not visible to the naked eye, and behavioural patterns obscured by diagenetic or biased processes during sampling.publishedVersio