Raw material quality and Oldowan hominin toolstone preferences: evidence from Kanjera South,Kenya

The role of raw material quality in Oldowan technology has not been fully explored. There are numerous studies suggesting Oldowan hominins preferred certain types of stone for artifact manufacture. Previous studies of the artifact assemblage from the early Pliocene Oldowan locality of Kanjera South (South Rachuonyo District, Kenya) show that raw material selection and transport was an important aspect of Late Pliocene hominin adaptations. Yet the exact properties of stones that hominins were selecting remain enigmatic. Two potentially important features of artifact raw material are durability and fracture predictability. We investigate fracture predictability through mechanical tests of stone and investigations of the affect of stone properties on fracture patterns in archaeological collections. We investigate stone durability with actualistic studies of edge attrition combined with further mechanical tests of various lithologies. Oldowan hominins at Kanjera appear to have selected raw materials based on their durability. The ability for a stone to fracture consistently does not appear to be as important in hominin toolstone preference as previously assumed. Hominins that produced the assemblages at Kanjera South appear to have incorporated an extensive understanding of various attributes of raw material in the transport and production of stone artifacts. When combined with previous research on the transport patterns at Kanjera, the results of this study provide evidence for a more complex raw material acquisition strategy than has previously been suggested for Late Pliocene Oldowan hominins.     

Oldowan behavior and raw material transport: perspectives from the Kanjera Formation

The archaeological record of Oldowan hominins represents a diverse behavioral system. It has been suggested that exploitation of lithic resources by Oldowan hominins was simplistic and represented mostly use of local sources of stone. Here we investigate the raw material selection and transport behaviors of Oldowan hominins reflected in the stone artifact assemblages from the Kanjera South Formation, South Rachuonyo District, Kenya. Using geochemical methods (ED-XRF) artifacts are linked to primary and secondary source outcrops throughout southwestern Kenya. These data show that hominins selected raw materials for transport at frequencies that are significantly different from their availability on ancient landscapes. Furthermore, a substantial proportion of the assemblage represents transport over relatively long distances (>10 km). Our study further suggests that in the early stages of stone tool use hominins used a wide variety of raw materials and selected these materials at some distance from their eventual discard locations. Early hominin behavior may have incorporated an understanding of raw material source distributions across a more extensive landscape than has been previously documented. This supports the growing perspective that Oldowan technology represents a more complex behavioral pattern than is usually associated with the beginnings of hominin tool use.     

The oldowan reassessed: A close look at early stone artifacts

Early Stone Age assemblages called “Oldowan” and early “Developed Oldowan” are discussed, based on the results of a long-term study of Plio-Pleistocene sites at Koobi Fora, Kenya and an extensive experimental research program of replicating and using early stone artifact forms. Five major conclusions are drawn from this investigation: (1) many Oldowan core forms (“core-tools”) are probably simple by-products of flake manufacture rather than representations of stylistic norms; (2) flakes and retouched flakes - were essential tools in Oldowan technology, particularly for activities involving cutting; (3) this simple technology does not necessarily reflect the cognitive abilities of the early hominids that manufactured the stone artifacts; (4) there is evidence to show that Oldowan technology can be viewed as a simple curated one, in which raw material was intentionally carried from place to place for future use; (5) early hominid populations that made and used stone implements were not necessarily dependent upon them for their survival.     

The World's Oldest Stone Artefacts from Gona, Ethiopia: Their Implications for Understanding Stone Technology and Patterns of Human Evolution Between 2·6–1·5 Million Years Ago

The systematic archaeological and geological survey and excavations at Gona between 1992–1994 led to the discovery of well-flaked stone artefacts which are currently the oldest known from anywhere in the world. More than 3000 surface and excavated artefacts were recovered at 15 localities documented east and west of the Kada Gona river. Based on radioisotopic dating (⁴⁰Ar/³⁹Ar) and magnetostratigraphy, the artefacts are dated between 2·6–2·5 million years ago (Ma). EG10 and EG12 from East Gona are the most informative with the highest density, providing the best opportunity for characterizing the oldest assemblages and for understanding the stone working capability of the earliest tool makers. Slightly younger artefact occurrences dated to 2·4–2·3 Ma are known from Hadar and Omo in Ethiopia, and from Lokalalei in Kenya. Cut-marked bones dated to 2·5 Ma from Bouri in Ethiopia are now providing important clues on the function of these artefacts. In addition, Australopithecus garhi known from contemporary deposits at Bouri may be the best candidate responsible for the oldest artefacts. Surprisingly, the makers of the Gona artefacts had a sophisticated understanding of stone fracture mechanics and control similar to what is observed for Oldowan assemblages dated between 2·0–1·5 Ma. This observation was corroborated by the recent archaeological discoveries made at Lokalalei. Because of the similarities seen in the techniques of artefact manufacture during the Late Pliocene–Early Pleistocene, it is argued here that the stone assemblages dated between 2·6–1·5 Ma group into the Oldowan Industry. The similarity and simplicity of the artefacts from this time interval suggests a technological stasis in the Oldowan.     

Debitage variability among multiple flint knappers

Five flint knappers produced both multidirectional cores and early stage bifaces. The debitage assemblages were compared to evaluate if, and to what degree, the debitage created by one flint knapper varies from that of other flint knappers. The debitage from these reduction episodes was then analyzed with commonly used and replicable debitage attributes. Each knapper was evaluated in terms of his/her individual consistency, and the debitage produced was tested for each ratio scale debitage attribute to ensure that the variability found between knappers was not a product of variation within the assemblages of the individual knappers. The debitage from the individual flint knappers was found to be highly variable between knappers for both technologies.     

Chipped Stone Debitage,Material Selection,and Expedient Tool Production in Southeast Michigan

Abstract

This article summarizes the results of exploratory analyses on material sources and debitage attributes from chipped stone artifacts at sites identified and sampled by the Eastern Michigan University Field School along the Huron River Valley in southeast Michigan. Several hypotheses are tested with chipped stone debitage assemblages from 35 prehistoric sites to better understand material selection, expedient versus formal tool manufacturing, and the influence of material availability and mobility in chipped stone processing within the region. The distribution of debitage attributes (reduction stage, technology, condition, and size) are first compared by material source and quality. Then, the distributions of materials and debitage attributes are compared among small limited-use sites and two early Late Woodland small settlements. The results indicate a heavy reliance on poorer quality local cherts, and a focus on expedient tool manufacturing with both the local poorer quality and the nonlocal higher quality sources. There were no major differences in debitage assemblages between the limited use sites and the settlements.     

The Transition to the Acheulean in East Africa: an Assessment of Paradigms and Evidence from Olduvai Gorge (Tanzania)

The origin of the Acheulean constitutes a key aspect of current research in the archaeology of human evolution. Olduvai Gorge is one of the main sites in Africa in the study of the transition from the Oldowan to the Acheulean, due to both the uniqueness of its archaeological record, and the influence of early investigations at Olduvai on the development of Early Stone Age research. This paper reviews the impact of work at Olduvai in shaping a modern view of cultural evolution from the Oldowan to the Acheulean. It also evaluates the lithic assemblages excavated by Mary Leakey in Olduvai Middle and Upper Bed II, based on a first-hand review of the collections. We conclude that previous paradigms used to explain inter-assemblage variability are not superseded as much as generally assumed, and that a modern view of the origins of the Acheulean requires a reassessment of the cultural, biological, and paleoecological evidence at Olduvai and elsewhere in Africa.     

Measuring core reduction using 3D flake scar density: a test case of changing core reduction at Klasies River Mouth,South Africa

A new core reduction index is presented, calculated as the ratio of flake scar number to 3D surface area (SDI). The index is tested experimentally on five types of core (blade, discoid, Levallois, biface and multiplatform cores) and then applied to the core assemblages from five sub-stages of the Middle Stone Age at Klasies River Mouth, South Africa. Preliminary results indicate that the SDI possesses the desirable attributes of a successful reduction index and is a significant improvement on traditional proxy measures of core reduction. The results of the archaeological case study confirm previous untested observations that cores from the Howiesons Poort and MSAIII sub-stages are more heavily reduced than preceding and following stages, and that local and exotic raw materials as well as different types of cores are all more heavily reduced during these periods. The SDI fills a significant lacuna in available core reduction measures.     

Comparison of Gadeb and other Early Stone Age assemblages from Africa south of the Sahara

An exploratory multivariate analysis is presented of 64 Early Stone Age tool-assemblages from sub-Saharan Africa. The results generally confirm, but contribute significantly to understanding, the conventional division of these assemblages between Oldowan, Karari, Early Acheulian and Acheulian industrial groupings. The distinction between Oldowan and Developed Oldowan is shown to be less clearly defined.

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Resumé L'auteur présente une analyse tentative à plusieurs variables de 64 groupes d'outils de l'Age de la Pierre Ancien en Afrique méridionale. Les résultats confirment en général—mais aussi contribuent considérablement à comprendre—la division conventionnelle de ces ensembles entre les groupements industriels de l'Oldowayen, le Karari, l'Acheuléen ancien et l'Acheuléen. La différence entre l'Oldowayen et l'Oldowayen évolué se montre moins clairement définie.

     

Core Use-Life Distributions in Lithic Assemblages as a Means for Reconstructing Behavioral Patterns

Artifacts with varying use-lives have different discard rates and hence are represented unequally among archaeological assemblages. As such, the ability to gauge the use-lives of artifacts is important for understanding the formation of archaeological assemblage variability. In lithic artifacts, use-life can be expressed as the extraction of utility, or work potential, from existing stone volume. Using experimental data and generalized linear modeling, this study develops models of artifact use-life on cores in the form of reduction intensity. We then apply these models to two archaeological case studies to (a) reconstruct the reduction intensities of archaeological cores and (b) investigate the survivorship curves of these archaeological cores across the reduction continuum using the Weibull function. Results indicate variation in core reduction and maintenance with respect to raw material properties and place use history and implicate evolutionary differences between Early Stone Age hominins and Holocene modern humans.     

Trampling vs. Retouch in a Lithic Assemblage: A Case Study from a Middle Stone Age Site,Steenbokfontein 9KR (Limpopo,South Africa)

At the site of Steenbokfontein 9KR, virtually 80% of the lithic blanks presented retouch—an extreme proportion for Middle Stone Age assemblages. The high percentage of putative retouch led us to investigate whether post-depositional processes played a role in the preservation of the lithic assemblage. We designed and performed an experiment that reproduced all the archaeological conditions inferred from the site formation analyses to determine if the archaeological assemblage was trampled or retouched. We defined several qualitative attributes and studied both trampled and retouched experimental samples, and compared them to the archaeological material. We subsequently performed different statistical analyses and a correspondence analysis with all the macro qualitative attributes that we defined. We were then able to discern which attributes were the most eloquent variables and assess the usefulness of a multivariate analysis in discriminating between trampling and retouch.     

Evaluating morphological variability in lithic assemblages using 3D models of stone artifacts

Technological and morphological variability in lithic artifacts is commonly used to identify taxonomic entities in Paleolithic research contexts. Assemblages are mainly studied using either linear distance measurements or qualitative assessments of morphologies. Here, we present a method to quantify morphological variability in lithic artifacts using 3D models of stone artifacts. Our study on the sequence of the Upper Paleolithic layers V–I from the site Yabroud II in western Syria, demonstrates that utilizing 3D models provides a new insight into the variability of lithic technologies. We use quantitative data on convexities, twist and scar patterns on cores and blades, attributes previously not readily quantifiable, to trace technological change through the archaeological sequence. We are able to identify differences and translate these findings into a grouping of the layers. While layers VI–II are characterized by technological continuity and were grouped together, layers V and I can be separated from this group and represent technologically different groups chronologically before and after. Our results demonstrate the potential of 3D models for studying morphological variability in lithic assemblages.     

Cut Mark Cluster Geometry and Equifinality in Replicated Early Stone Age Butchery

Early Stone Age cut marks created during tool‐assisted carnivory potentially offer inferences into hominin butchery behaviour and access to complete or defleshed carcasses. Actualistic butchery trials of 16 goat and cow half‐carcasses were completed by an experienced butcher with replicated Oldowan tools to investigate how the geometric organisation of cut mark clusters reflects flake versus core tool use and bulk muscle versus scrap defleshing. A cluster of cut marks is defined as a series of adjacent cut mark striations that occur at an anatomical location and are bounded by unmarked cortical surface. Tool type and butchery action were predicted to differentially mark certain long bone portions and influence cluster attributes. Moulds of 613 cut mark clusters were photographed and measured using ImageJ software (National Institutes of Health, Bethesda, Maryland, USA) for cluster area, cut mark count, median cut mark length and standard deviation of cut mark length and angle. Analysis suggests the following results: (i) cluster attributes are correlated;(ii) changes in cluster geometry are related to increasing cut mark count and length but not tool type or defleshed muscle amount; (iii) large clusters occur on large animals; and (iv) long bone midshaft portions are cut‐marked during both bulk and scrap muscle defleshing. Analysis of 179 cut mark clusters on long bone shafts of sizes 1–4 mammals from three Okote member assemblages at Koobi Fora, Kenya, shows that archaeological clusters have a similar number of marks when compared with experimental clusters but are significantly smaller, have shorter median marks and include less deviation in mark length and angle. Archaeological clusters corroborate that increasing area is positively correlated with cut mark count, median mark length and standard deviation of mark length and angle. A quantitative inferential model that links cut mark cluster geometry to tool type or the amount of muscle defleshed is not supported by these data. Copyright © 2015 John Wiley & Sons, Ltd.     

Effects of distance from stone source on landscape-scale variation in Oldowan artifact assemblages in the Paleo-Olduvai Basin,Tanzania

Ongoing excavations at Olduvai Gorge, Tanzania, reveal tremendous variability among stone artifact assemblages across the Plio-Pleistocene Olduvai Lake Basin during Bed I and lower Bed II times. Theoretically, stone artifact traces of Oldowan hominin land use are determined by the distribution of larger mammal carcasses and arboreal refuge from predation as well as proximity to stone material sources.     

The Taphonomy of Resource Intensification: Zooarchaeological Implications of Resource Scarcity Among Bofi and Aka Forest Foragers

Zooarchaeological analyses often rely on bone fragmentation, cut marks, and other taphonomic indicators to bolster interpretations of resource intensification that are based on observed changes in prey types and frequencies. While these taphonomic indicators are assumed to be good proxy measures of processing effort, this assumption is based on inadequate actualistic data and analysts often conflate one or more taphonomic indicators as manifestations of the same process. In this paper, we present zooarchaeological data from two villages occupied by Central African forest foragers with very different foraging efficiencies. These data provide the first case where known disparities in diet breadth and foraging efficiency are matched with prey assemblages and taphonomic attributes. Observational and quantitative data show differences between the villages in diet breadth and access to high-ranked prey, but specific taphonomic indicators such as cut mark distribution and intensity do not match predictions generated from models of resource intensification. We propose that linking different taphonomic processes to resource scarcity and intensification can provide powerful adjunctive information. However, because different processing outcomes may be associated with different kinds of resource intensification in response to different kinds of scarcity, we need to strengthen the validity of purported taphonomic indicators with more rigorous independent studies.     

Research on the Palaeolithic and Neolithic of Hadramaut and Mahra

This paper presents some of the results of exploration and excavation by the Soviet-Yemeni expedition carried out between 1983 and 1990 in Hadramaut and Mahra. Oldowan, Acheulean, Middle Palaeolithic, Upper Palaeolithic, and'Neolithic'stone tool industries are attested, providing what is probably the most detailed sequence covering these periods in the entire Arabian peninsula.     

A method for estimating edge length from flake dimensions: use and implications for technological change in the southern African MSA

This paper presents a method for estimating edge length from flake dimensions. Comparison of estimated values with data from measured flake edges demonstrates the robusticity of the method. Building on the work of Braun (Braun, D.R., 2005. Examining flake production strategies: examples from the Middle Paleolithic of Southwest Asia. Lithic Technology 30, 107–125; Braun, D.R., Harris, J.W.K., 2003. Technological developments in the Oldowan of Koobi Fora: innovative techniques of artifact analysis and new interpretations of Oldowan behavior, in Mora, R., de la Torre, I. (Eds.), Oldowan: Rather More than Smashing Stones. Treballs d’ Arqueologia 9, pp. 132–144) this estimate is used to generate an edge length to mass value for complete flakes—taken to be a proxy for flaking efficiency. It is shown that this value is useful in tracking the onset, variability and decline of a well known technological phase—the Howiesons Poort of South Africa. The results suggest that the Howiesons Poort was a time in which flaking efficiency was emphasised. Furthermore, comparison of upper limits of edge to mass values for different raw materials may provide an insight into changes in raw material selection.     

Particle size distribution of lithic assemblages and taphonomy of Palaeolithic sites

Lithic debris derived from knapping and used tools can be assimilated to simple sedimentary particles that may undergo size sorting when exposed to geomorphic processes such as streamflow or overland flow. Sorting can be identified by comparing the size distribution of archaeological assemblages to that of experimental core reduction sequences. A new database including different types of raw material (mainly flint and quartzite) and Palaeolithic debitage (blade, Levallois, discoid, on anvil, and shaping) has been built for this purpose. Palaeoeskimo data have also been added to illustrate microlithic industries. For all the debitages and raw materials, the particle size of knapping products >2 mm in width fits with a power-law distribution and shows only minor fluctuations, the range of which is always <15% between experiments (all steps of the chaîne opératoire included up to the final tool). A lithic assemblage derived from block/core knapping or blank/preform production will display a particle size distribution close to the experimental distributions if not subsequently modified. Modifications may originate either from sedimentary processes or from anthropogenic factors. To help distinguishing amongst these, data on the impact of both water flows on sedimentary particles or experimental assemblages, and anthropogenic processes such as importation-exportation (of core, preforms or finished tools) or uneven spatial distribution of the different steps in core reduction and tool production within a site, are reviewed. By contrast to anthropogenic modifications, sedimentary processes are generally typified by strong impoverishment in or selective accumulation of fine-grained (<10 mm) artefacts together with a low intra-site variability (spatial homogenization) or a downslope size trend. Archaeological case studies taken from French Palaeolithic site are then detailed. Evidence for lithic redistribution implies that care should be taken in archaeological site analysis since sorting may impact significantly the initial techno-typological balance of the assemblage.     

The reconstruction of past environments through small mammals: from the Mousterian to the Bronze Age in El Mirón Cave (Cantabria,Spain)

El Mirón is a large cave in the Cantabrian Cordillera of northern Spain that presents a long archaeostratigraphic sequence radiocarbon-dated by over 60 assays to between 41,000 and 2000 BP. The sediments, collected from four areas within the cave and sieved-washed with fine wire meshes, contain microvertebrate remains of fish, frogs, lizards, birds and mammals, of which the latter are most abundant. Preliminary taphonomic analysis suggests that the microvertebrates were naturally collected by owls and (less) small carnivores. Small mammal assemblages are useful for palaeoenvironmental reconstruction because they are linked to particular habitats and are sensitive to environmental changes. The small mammals from El Mirón are ideal for this because sample sizes are large, bone preservation is good, and the stratigraphic sequence is long. In this paper we reconstruct the late Quaternary environments in the Cantabrian region of Spain using small-mammal assemblages from El Mirón Cave. On the basis of the ecologic adaptations of this suite of fauna, the majority still extant, we have identified seven habitat types, which are plotted through time. The evolution of the small mammal assemblages at El Mirón reveals seven major climatic shifts that correspond closely to the climatic changes recognized in the Iberian Peninsula during the last 41 kyr.