A biface and blade core efficiency experiment: implications for Early Paleoindian technological organization

Early Paleoindians often are described as highly mobile hunter–gatherers who employed lithic technologies designed to minimize stone transport costs. We experimentally reduced blade and bifacial cores and found both reduction strategies to be equally efficient for the production of useable flake blanks. Further, when compared to similar core reduction experiments, the results of this study showed no significant differences in core efficiency between bifacial, prismatic blade, and wedge-shaped blade core reduction. Biface and blade cores with initial weights greater than 1000 g produced useable flakes as efficiently as informal cores. However, bifacial and blade core efficiency decreased with initial core weight. When considered in terms of Early Paleoindian technological organization, differences in core efficiencies suggest that Folsom groups employed core reduction strategies designed to minimize stone transport costs, but Clovis groups did not.     

Geology and lithic procurement in Upper Palaeolithic Europe: a weights-of-evidence based GIS model of lithic resource potential

In this paper we examine ways to predict the distribution of siliceous rock in Europe, using a Bayesian technique known as ‘Weights-of-Evidence’. We use the technique to classify bedrock geological formations in terms of their likelihood of yielding tool-quality lithic raw materials, and we use the results to re-examine possible causes of a west–east cline in maximum lithic raw material transfer distances observed when comparing sites in both Middle and Upper Palaeolithic Europe. It is evident from our results that there is a decline in abundance of geological formations highly predictive of tool-quality rock along a west–east cline, predominantly reflecting a decrease in abundance of Jurassic and Cretaceous chert-bearing sedimentaries. Our results are consistent with an interpretation of the Upper Palaeolithic record of transfer distances as indicating special-purpose procurement.     

Variability in bifacial technology at Elandsfontein,Western cape,South Africa: a geometric morphometric approach

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.     

Experimental analysis of the practical limits of lithic refitting

We report on the results of an experiment aimed at determining the effects of experience/aptitude, lithic reduction type (biface v. core), and flake size cut-offs on different rates of success in refitting studies. We found that experience matters, but that there can be large differences in aptitude for refitting; that cores are easier to refit than bifaces; and that the effort of refitting increases considerably for flakes smaller than 5–6 g. We propose the use of an asymptotic equation fit to a cumulative curve as a way to determine when a study has reached the point of diminishing returns for a given flake size cut-off, and to help determine differences in aptitude for refitting.     

Quantifying flake scar patterning on cores using 3D recording techniques

A key feature of stone artefact morphology is the arrangement and patterning of negative flake scars left on flakes and cores. Scar patterning is often treated as a rough guide to identifying methods of core preparation and reduction and usually forms a key component of lithic typologies and other systems of analysis. However, scar patterns are often complex and difficult to capture using traditional measurement or classificatory techniques, particularly where flakes are thick and irregular, or where cores are flaked on many sides from a number of platforms. Three-dimensional analysis of flake scars is now more feasible using digital 3D surface scanning technologies, or using three-dimensional measurement tools such as the Microscribe-3DX which is now widely used in biological geometric morphometric studies more generally [D.C. Adams, F.J. Rohlf, D.E. Slice, Ital. J. Zool., 71 (2004) 5–16; F.J. Rohlf, L.F. Marcus, Trends Ecol. Evol. 8 (1993) 129–132. [1 and 34]]. This paper develops a mathematical formula for describing scar patterning using vectors calculated from the start and end points of flake scars recorded in three dimensions.     

A tale of two sites: Functional site differentiation and lithic technology during the Late Pithouse period in the Mimbres area of Southwestern New Mexico

The raw materials from which stone tools are made can provide considerable information relevant to behavioral variation within a prehistoric population. By examining the stone used for tools from two different types of Late Pithouse period (A.D. 550-1000) residential sites from the Mimbres Mogollon area of Southwestern New Mexico, this paper illustrates how understanding the lithic landscape of a region provides a means to assess behavioral variation in stone procurement practices. The analysis indicates that the differences in mobility and economic pursuits between longer-term residential sites containing pit structures and a shorter-term seasonal residential site with ephemeral architecture structured the raw material procurement practices of site’s occupants. Pit structure sites were focused on agricultural pursuits and used a technology that centered on the production of informal tools fashioned from locally available raw materials. The seasonal residential site focused on wild resources and evidenced greater reliance on formal tool production using raw materials acquired from beyond the immediate vicinity of the site. Despite increasing sedentism and agricultural dependence of the region’s population, some portion of the population exercised seasonal mobility strategies and associated technological and behavioral practices more typical of hunting and gathering populations, suggesting a diverse socio-economic system within the region.     

Application of a new typological approach to classifying denticulate and notched tools: the study of two Mousterian lithic assemblages

Identifying tools by means of morphological attributes are widely used in lithic studies to categorize retouched artifacts from different archaeological periods. This procedure has facilitated the exchange of information between separate researchers and has improved the comparison of different assemblages. In these classifications, denticulates and notched tools have been regularly interpreted as analogues and chronologically unvaried in different and vast territories. Based on the definitions developed by Bordes, the denticulate category has become a catchall for any kind of tool bearing concavities. In this paper a new quantitative approach to the classification of denticulates and notched tools is proposed. The new methodology is based on measuring the length of notches and their distribution on the perimeter of the blank. Analyzing the lithic series of the Abric Romaní rock-shelter (Spain) and Grotta Maggiore di San Bernardino (Italy) led to the identification of 11 redundant forms: eight denticulates and three notched tools. Moreover, the application of Kuhn’s Geometric Index of Unifacial Reduction brought local manufacturing trends to light, calling into question the presumed geographical uniformity of these categories of artifacts.     

东秦岭山地商洛市和山阳县新发现的两处旧石器地点

上世纪70～80年代以来,东秦岭山区的古人类和旧石器考古调查及发掘工作取得了较大的进展,一大批重要的古人类或旧石器遗址相继被发现,它们对研究中国远古人类和南北旧石器工业的发展与演化、黄土堆积地层具有十分重要     

Toolstone constraints on knapping skill: Levallois reduction with two different raw materials

Lithic raw material constraints are widely assumed to be a determining factor of flaked stone tool morphology, but this assumption remains largely untested. We conducted a controlled experiment to determine whether a knapper’s growing replication skills would be hindered if the toolstone used was switched from large flakes of an easily worked chert to nodules of less tractable one. Two batches of Preferential Levallois cores were knapped, an earlier series made from standardised large flakes of sediments dominated by chalcedonic quartz followed by a more challenging one using variably-shaped, cortical nodules of microcrystaline quartz that varies in the completeness of quartz replacement of calcite and dolomite. Skill level markers were designed to measure the knapper’s ability to achieve a series of set goals. These were quantified and subjected to statistical testing. In all but one test, significant increases in skill could be detected from the earlier to the later batch of reductions, despite the drop in toolstone quality. Significant improvements in the consistency of the knapper’s output could also be detected. However, the switch to a more challenging, nodular chert did require extra shaping, which resulted in more waste. This masked visible progress towards producing a less costly core. Overall, our results do not support the assumed primacy of toolstone constraints over other factors in influencing the morphology of flaked stone tools.     

Blade technology and tool forms in the Middle Stone Age of South Africa: the Howiesons Poort and post-Howiesons Poort at Rose Cottage Cave

It has been suggested that between 80 and 35 ka the Middle Stone Age record of South Africa reveals episodes of inventiveness and innovation, punctuated by apparent returns to more conventional technologies. One such episode is the Howiesons Poort (HP). The appearance of a range of small geometric forms, apparently used as insets in multi-component tools, has been considered as evidence of improved hunting weapons, with possible social and symbolic connotations. On the basis of evidence such as backed tool production, small blade technology, the occurrence of typical end-scrapers and burins similar to those encountered in the European Upper Paleolithic, long-distance transport of fine-grained raw materials, and non-lithic novelties, the HP is associated with increased levels of technological efficiency and with behavioral innovations that could have allowed the expansion of African populations to other regions. Yet our knowledge of HP technology and tool production is limited to the analysis of Klasies River Main site by Singer and Wymer and Sarah Wurz, and a few preliminary reports from other sites. This is why we present here a detailed technological and typological analysis of several HP and post-HP assemblages from the well-excavated, well-dated and well-stratified site of Rose Cottage. Our analysis shows: (a) that the HP blade production was a real technical innovation, but was not based on indirect percussion, as often suggested; (b) that blade production was based on the use of marginal percussion which does not occur in the blade production of the Eurasian Middle Paleolithic; (c) that the tool kit was dominated by backed pieces, but not all can be considered as hunting weapons; (d) that neither end-scrapers nor burins are typical of this industry and are no more an antecedent to the European Upper Paleolithic than the end-scrapers and burins of the Middle Paleolithic; (e) that patterns of raw material procurement do not conform to models based on evidence from Klasies; (f) that diachronic changes within the Rose Cottage sequence indicate slow, gradual abandonment of the technological style of the HP; (g) that the post-HP assemblages are of MSA character and are typologically and technologically quite similar to the European Middle Paleolithic; (h) that the lack of persistence of the HP innovations is in need of an explanation. The HP is not a monolithic entity. Implications for the symbolic interpretations of the HP phenomenon are discussed.