Landscape perspectives on variability in the Acheulean behavioural system in sub-Saharan Africa: A view from Koobi Fora and Elandsfontein

The emergence of the Acheulean is understood to mark a key adaptive shift in several dimensions of hominin behaviour. Some archaeologists associate the onset of the Acheulean at ~1.7 Ma with the expansion of hominin foraging ranges involving increased mobility and tool transport distances, variability in strategies of stone raw material procurement and use and increased spatial and temporal depths of planning in the organization of stone tool production. Other scientists view Acheulean hominins as being tied to water and water related resources, as well as to stone raw-material sources across the landscape. In this second model, hominins rarely planned subsistence and technological activities in substantial spatial or temporal anticipation of future need. Very little quantitative archaeological data, however, have been published to support either of these models. We need to understand how Acheulean hominins organized and economized their technology on a landscape scale, to make quantitative assessments about how shifts in hominin cognition are manifested archaeologically. Here I develop a series of methods to (1) interrogate how Acheulean hominins organized and economized their technology on a landscape scale, and to (2) quantitatively assess how shifts in hominin cognition are manifested archaeologically. Few contexts exist that are conducive to such studies. Two of the more suitable sets of sites are (a) a set of spatially separated semi-contemporaneous early Acheulean (~1.4 Ma) sites in Koobi Fora, east Turkana, Kenya, consisting of the localities of FxJj65, FxJj63, FxJj37 and FxJj21, and, (b) a ~10 km2 dune field with multiple later Acheulean localities known as Elandsfontein, West Coast, South Africa (~1 Ma-600 Ka). Quantitative and qualitative analyses demonstrate that archaeological sites at Koobi Fora and at Elandsfontein were ‘fragmented’. In other words, hominins structured their tool manufacture, use, and maintenance patterns spatially across the landscape, a pattern that is not evident in the archaeological record preceding the Acheulean. This finding suggests that fragmentation may be a ‘pan-African’ feature of Acheulean hominin behaviour, potentially conflicting with inferences that Acheulean hominins were tied to resources, and did not plan their activities beyond immediate expedient tool manufacture and use. This thesis proposes a model wherein early and later Acheulean hominins used the landscape in flexible and systematic ways, at the geographic extremes of sub-Saharan Africa, implying a depth of planning in Acheulean hominins wherein technological activities were undertaken in substantial anticipation of future needs

Documenting differences between early stone age flake production systems: An experimental model and archaeological verification

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

Quantifying traces of tool use: a novel morphometric analysis of damage patterns on percussive tools

Percussive technology continues to play an increasingly important role in understanding the evolution of tool use. Comparing the archaeological record with extractive foraging behaviors in nonhuman primates has focused on percussive implements as a key to investigating the origins of lithic technology. Despite this, archaeological approaches towards percussive tools have been obscured by a lack of standardized methodologies. Central to this issue have been the use of qualitative, non-diagnostic techniques to identify percussive tools from archaeological contexts. Here we describe a new morphometric method for distinguishing anthropogenically-generated damage patterns on percussive tools from naturally damaged river cobbles. We employ a geomatic approach through the use of three-dimensional scanning and geographical information systems software to statistically quantify the identification process in percussive technology research. This will strengthen current technological analyses of percussive tools in archaeological frameworks and open new avenues for translating behavioral inferences of early hominins from percussive damage patterns.Palaeontological Scientific Trust; National Research Foundation; National Science Foundation [BCS-1128170, BCS-0924476]; Integrative Graduate Education and Research Traineeship Program [DGE-0801634]; George Washington University's Selective Excellence Fund; George Washington University Columbian College Facilitating Fund; Clare Hall College [JRF]; Newnham College [Gibbs Travelling Fellowship] Cambridge; European Research Council [283959]info:eu-repo/semantics/publishedVersio

The first Miocene fossils from coastal woodlands in the southern East African Rift

The Miocene was a key time in the evolution of African ecosystems witnessing the origin of the African apes and the isolation of eastern coastal forests through an expanding arid corridor. Until recently, however, Miocene sites from the southeastern regions of the continent were unknown. Here, we report the first Miocene fossil teeth from the shoulders of the Urema Rift in Gorongosa National Park, Mozambique. We provide the first 1) radiometric ages of the Mazamba Formation, 2) reconstructions of paleovegetation in the region based on pedogenic carbonates and fossil wood, and 3) descriptions of fossil teeth. Gorongosa is unique in the East African Rift in combining marine invertebrates, marine vertebrates, reptiles, terrestrial mammals, and fossil woods in coastal paleoenvironments. The Gorongosa fossil sites offer the first evidence of woodlands and forests on the coastal margins of southeastern Africa during the Miocene, and an exceptional assemblage of fossils including new species

Table shows the results of the Generalized Linear Model including only non-cortical flakes (n = 198).

<p>(1) not shown because of not having any meaningful interpretation</p><p>(2) all covariates were z-transformed to a mean = 0 and sd = 1, original means (sd) were: curvature: 175.13(10.76); epa: 67.26(15.02); thickness evenness: 2.53 (2.18); platform depth: 9.67(6.68)</p><p>(3) square root transformed prior to z-transformation</p><p>(4) standardized by the geomean</p><p>Table shows the results of the Generalized Linear Model including only non-cortical flakes (n = 198).</p

The results of the reduced Generalized Linear Model, with no interactions.

<p>(1) not shown because of not having any meaningful interpretation</p><p>(2) all covariates were z-transformed to a mean = 0 and sd = 1, original means (sd) were: curvature: 175.67(10.61); epa: 68.46(14.90); thickness evenness: 2.71 (2.18); platform depth: 10.53(6.82)</p><p>(3) square root transformed prior to z-transformation</p><p>(4) standardized by the geometric mean</p><p>The results of the reduced Generalized Linear Model, with no interactions.</p

The classification of archaeological material.

<p>Histogram showing the results of classifying Elandsfontein Cutting 10 using the discriminant function analysis model built with the experimental dataset.</p

The results of the discriminant function analysis on experimental assemblage showing the loadings of the linear discriminant 1.

<p>The results of the discriminant function analysis on experimental assemblage showing the loadings of the linear discriminant 1.</p

Thickness evenness coefficient.

<p>Arrows show points of percussion, whereas solid lines represent places on a flake where thickness was measured.</p