Skill Matters

Skill is a challenging topic for archeologists because it requires balancing the biases of cultural relativity with the commonsense understanding that some humans are more able than others. Using the content and results model of technology, this paper identifies skill as a variable of technological knowledge with recognizable material results. Late Paleolithic Japanese blade and microblade assemblages suggest that skill differentials exist on the cognitive, operational, and motor levels. These examples, together with ethnoarcheological consideration of modern potters suggest material reflections of technical skill. These include regularity in performance and product, skilled tools, and obvious signs of practice.     

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.     

New radiometric ages for the Fauresmith industry from Kathu Pan,southern Africa: Implications for the Earlier to Middle Stone Age transition

The Fauresmith lithic industry of South Africa has been described as transitional between the Earlier and Middle Stone Age. However, radiometric ages for this industry are inadequate. Here we present a minimum OSL age of 464 ± 47 kyr and a combined U-series–ESR age of 542₋₁₀₇⁺¹⁴⁰ kyr for an in situ Fauresmith assemblage, and three OSL ages for overlying Middle and Later Stone Age strata, from the site of Kathu Pan 1 (Northern Cape Province, South Africa). These ages are discussed in relation to the available lithostratigraphy, faunal and lithic assemblages from this site. The results indicate that the Kathu Pan 1 Fauresmith assemblage predates transitional industries from other parts of Africa e.g. Sangoan, as well as the end of the Acheulean in southern Africa. The presence of blades, in the dated Fauresmith assemblages from Kathu Pan 1 generally considered a feature of modern human behaviour ( McBrearty and Brooks, 2000, The revolution that wasn't: a new interpretation of the origin of modern human behavior, J. Human Evolution 39, 453–563),-provides evidence supporting the position that blade production in southern Africa predated the Middle Stone Age and the advent of modern Homo sapiens.     

An estimator for bidirectional (naviform) blade productivity in the Near Eastern Pre-Pottery Neolithic B

A method is presented for calculating the blade productivity of bidirectional (naviform) blade cores, a hallmark of Near Eastern Pre-Pottery Neolithic B (PPNB) chipped stone tool assemblages. This approach involves estimating the volume of the core that furnished serial blades, together with the mean volume of a typical targeted blade blank. Simple computation of the volume of a wedge in both instances provides an estimate of the number of targeted blades that were produced in an average single reduction sequence. The method is checked against two replicated bidirectional blade reduction sequences, and a refitted bidirectional blade core from the site of Kfar HaHoresh, Israel. Finally, a case study from Kfar HaHoresh is presented in order to illustrate the application of the method, which may have ramifications concerning the evaluation of incipient craft specialization in the region.     

Effect of heat treatment on siliceous rocks used in prehistoric lithic technology

Stone tool manufacture by many prehistoric and recent societies was characterized by deliberate heating of fine grained siliceous rocks to improve their flaking properties. Extensive mechanical testing of heated and unheated cryptocrystalline and macrocrystalline quartz lithologies has shown that thermal treatment causes a consistent marked reduction in fracture toughness. This mechanical property can be used as an objective measurement of the flaking qualities of stone materials, and a reliable criterion for the recognition of intentionally heated artefacts in the archaeological record. X-ray diffraction studies and scanning electron microscopy have demonstrated that the change in fracture toughness with heating is the result of recrystallization. The poorly ordered, strongly interlocking cryptocrystalline fabric of the unheated samples becomes more equigranular and better crystallized with thermal treatment. As a consequence, fractures propagate more readily in heated samples, accounting for their better flaking properties.     

A geometric morphometrics-based assessment of blade shape differences among Paleoindian projectile point types from western North America

Blade shape features in the type definitions of Clovis, Folsom, and Plainview projectile points. However, the accuracy of these assessments has never been evaluated. Here we report a study in which geometric morphometrics and multivariate statistics were used to compare the shapes of the blades of Clovis, Folsom and Plainview points from the Southern Plains of North America. In the course of the analyses, we controlled for the impact of three potential confounding factors: allometry, differences in raw material quality, and resharpening. The analyses show that blade shape distinguishes Clovis points from both Folsom points and Plainview points, but does not distinguish Folsom points from Plainview points. The analyses also show that the similarities and differences in blade shape among the types are independent of allometry, raw material quality, and resharpening. These findings suggest that the type definitions for Clovis, Folsom and Plainview need to be altered. They also have implications for typing specimens that lack other defining characters (e.g. channel flakes, flutes). Lastly, the absence of resharpening effects raises questions about the validity of the reduction thesis.