Browsing by Author "Braun, David R"

Now showing 1 - 9 of 9
  • Thumbnail Image
    Item
    Open Access
    Documenting differences between early stone age flake production systems: An experimental model and archaeological verification
    (Public Library of Science, 2015) Presnyakova, Darya; Archer, Will; Braun, David R; Flear, Wesley
    This study investigates morphological differences between flakes produced via “core and flake” technologies and those resulting from bifacial shaping strategies. We investigate systematic variation between two technological groups of flakes using experimentally produced assemblages, and then apply the experimental model to the Cutting 10 Mid -Pleistocene archaeological collection from Elandsfontein, South Africa. We argue that a specific set of independent variables--and their interactions--including external platform angle, platform depth, measures of thickness variance and flake curvature should distinguish between these two technological groups. The role of these variables in technological group separation was further investigated using the Generalized Linear Model as well as Linear Discriminant Analysis. The Discriminant model was used to classify archaeological flakes from the Cutting 10 locality in terms of their probability of association, within either experimentally developed technological group. The results indicate that the selected independent variables play a central role in separating core and flake from bifacial technologies. Thickness evenness and curvature had the greatest effect sizes in both the Generalized Linear and Discriminant models. Interestingly the interaction between thickness evenness and platform depth was significant and played an important role in influencing technological group membership. The identified interaction emphasizes the complexity in attempting to distinguish flake production strategies based on flake morphological attributes. The results of the discriminant function analysis demonstrate that the majority of flakes at the Cutting 10 locality were not associated with the production of the numerous Large Cutting Tools found at the site, which corresponds with previous suggestions regarding technological behaviors reflected in this assemblage.
  • Thumbnail Image
    Item
    Open Access
    Earliest stone-tipped projectiles from the Ethiopian Rift date to> 279,000 years ago
    (Public Library of Science, 2013) Sahle, Yonatan; Hutchings, W Karl; Braun, David R; Sealy, Judith C; Morgan, Leah E; Negash, Agazi; Atnafu, Balemwal
    Projectile weapons (i.e. those delivered from a distance) enhanced prehistoric hunting efficiency by enabling higher impact delivery and hunting of a broader range of animals while reducing confrontations with dangerous prey species. Projectiles therefore provided a significant advantage over thrusting spears. Composite projectile technologies are considered indicative of complex behavior and pivotal to the successful spread of Homo sapiens . Direct evidence for such projectiles is thus far unknown from >80,000 years ago. Data from velocity-dependent microfracture features, diagnostic damage patterns, and artifact shape reported here indicate that pointed stone artifacts from Ethiopia were used as projectile weapons (in the form of hafted javelin tips) as early as >279,000 years ago. In combination with the existing archaeological, fossil and genetic evidence, these data isolate eastern Africa as a source of modern cultures and biology.
  • Thumbnail Image
    Item
    Open Access
    Hominin technological behavior during the later middle Pleistocene in the Gademotta formation, main Ethiopian rift
    (2013) Chemere, Yonatan Sahle; Braun, David R; Sealy, Judith C
    Includes abstract. Includes bibliographical references.
  • Thumbnail Image
    Item
    Open Access
    Investigating the signature of aquatic resource use within Pleistocene hominin dietary adaptations
    (Public Library of Science, 2013) Archer, Will; Braun, David R
    There is general agreement that the diet of early hominins underwent dramatic changes shortly after the appearance of stone tools in the archaeological record. It is often assumed that this change is associated with dietary expansion to incorporate large mammal resources. Although other aspects of the hominin diet, such as aquatic or vegetal resources, are assumed to be a part of hominin subsistence, identifying evidence of these adaptations has proved difficult. Here we present a series of analyses that provide methodological support for the inclusion of aquatic resources in hominin dietary reconstructions. We suggest that bone surface modifications in aquatic species are morphologically distinguishable from bone surface modifications on terrestrial taxa. We relate these findings to differences that we document in the surface mechanical properties of the two types of bone, as reflected by significant differences in bone surface microhardness values between aquatic and terrestrial species. We hypothesize that the characteristics of bone surface modifications on aquatic taxa inhibit the ability of zooarchaeologists to consistently diagnose them correctly. Contingently, this difficulty influences correspondence levels between zooarchaeologists, and may therefore result in misinterpretation of the taphonomic history of early Pleistocene aquatic faunal assemblages. A blind test using aquatic specimens and a select group of 9 experienced zooarchaeologists as participants was designed to test this hypothesis. Investigation of 4 different possible explanations for blind test results suggest the dominant factors explaining patterning relate to (1) the specific methodologies employed to diagnose modifications on aquatic specimens and (2) the relative experience of participants with modifications on aquatic bone surfaces. Consequently we argue that an important component of early hominin diets may have hitherto been overlooked as a result of (a) the paucity of referential frameworks within which to identify such a component and (b) the inability of applied identification methodologies to consistently do so.
  • Thumbnail Image
    Item
    Open Access
    A landscape approach to the surface archaeology of the Bos River, Tankwa Karoo, Northern Cape
    (2017) Shaw, Matthew; Parkington, John; Braun, David R
    Much of our current understanding of prehistoric human behavioural patterns during the Stone Age, is derived particularly from a robust set of chronological and technological sequences from caves and rock shelters, with some focus on open-air sites. The information gained from shelters cannot be ignored or downplayed, however, they offer a spatially and temporally limited view of prehistoric lifeways. The aim of this thesis is to provide an understanding of landscape use during the Stone Ages along the Bos River in the Tankwa Karoo, Northern Cape. Surveys were carried out around the Bos River, with the intention of mapping out and analysing all the surface stone artefacts. Analysing at the scale of the individual artefact, particularly temporally iconic artefacts, permits the landscape, although geologically and ecologically variable, to be viewed as a continuous space. The benefit of this approach allows for all artefacts across all types of settings to be analysed, providing a spatially subjective distribution of artefacts across the landscape. The evidence described in this thesis demonstrates an episodic occupation of the Tankwa Karoo during periods of increased resources, particularly the availability of food. The Bos River is a low-energy river that receives little rain and does not facilitate the formation of large rounded cobbles and boulders, explaining the lack of an occupation during the Earlier Stone Age (ESA), whereas an expedient organisation of locally sourced raw materials for stone tools characterise the Middle Stone Age (MSA) and Later Stone Age (LSA) periods in the Tankwa Karoo.
  • Thumbnail Image
    Item
    Open Access
    Oldest evidence of toolmaking hominins in a grassland-dominated ecosystem
    (Public Library of Science, 2009) Plummer, Thomas W; Ditchfield, Peter W; Bishop, Laura C; Kingston, John D; Ferraro, Joseph V; Braun, David R; Hertel, Fritz; Potts, Richard
    BACKGROUND: Major biological and cultural innovations in late Pliocene hominin evolution are frequently linked to the spread or fluctuating presence of C 4 grass in African ecosystems. Whereas the deep sea record of global climatic change provides indirect evidence for an increase in C 4 vegetation with a shift towards a cooler, drier and more variable global climatic regime beginning approximately 3 million years ago (Ma), evidence for grassland-dominated ecosystems in continental Africa and hominin activities within such ecosystems have been lacking. METHODOLOGY/PRINCIPAL FINDINGS: We report stable isotopic analyses of pedogenic carbonates and ungulate enamel, as well as faunal data from ∼2.0 Ma archeological occurrences at Kanjera South, Kenya. These document repeated hominin activities within a grassland-dominated ecosystem. Conclusions/Significance These data demonstrate what hitherto had been speculated based on indirect evidence: that grassland-dominated ecosystems did in fact exist during the Plio-Pleistocene, and that early Homo was active in open settings. Comparison with other Oldowan occurrences indicates that by 2.0 Ma hominins, almost certainly of the genus Homo , used a broad spectrum of habitats in East Africa, from open grassland to riparian forest. This strongly contrasts with the habitat usage of Australopithecus , and may signal an important shift in hominin landscape usage.
  • Thumbnail Image
    Item
    Open Access
  • Thumbnail Image
    Item
    Open Access
    The sword in the stone : lithic raw material in the Middle Stone Age at Pinnacle Point Site 5-6, southern Cape, South Africa
    (2011) Brown, Kyle S; Braun, David R; Sealy, Judith
    This thesis presents a description and analysis of the lithic artefacts from the recently excavated site of Pinnacle Point 5-6, Mossel Bay, from a sequence dating between ~50-85ka. PP5-6 has been excavated to the highest contemporary standards, enabling a more detailed analysis of the lithics than is possible for Klasies. Although the PP5-6 lithic sequence conforms with the overall trends of MSA artifact manufacture, a number of differences from other sites are identified here for the first time - a significant step towards understanding behavioral variability and complexity among early modern humans.
  • Thumbnail Image
    Item
    Restricted
    Variability in bifacial technology at Elandsfontein, Western Cape, South Africa: a geometric morphometric approach
    (Elsevier, 2010) Archer, Will; Braun, David R
    This study applies a new three-dimensional measurement technique to determine the major source of variation in the Acheulian bifacial tool collection from the Middle Pleistocene site of Elandsfontein, South Africa. This three-dimensional technique is compared with conventional two-dimensional methods to investigate which methods capture morphological variation in the assemblage most comprehensively. Additionally, a set of experimentally produced bifacial tools are incorporated into the analyses to isolate the behavioral pattern underpinning identified variation in the archaeological assemblage. The interpretative breadth of current models explaining morphological variation in bifacial tools is then tested against the pattern identified in the Elandsfontein assemblage. Variation appears to be related to the consistent application of a specific reduction strategy associated with the early stages of bifacial tool manufacture. The intensity with which this strategy was applied seems to have been mediated by the availability of raw material that was suitable for the production of large bifacial tools.