Striking a difference? The effect of knapping techniques on blade attributes

Studies of lithic blade technology offer an important step towards explanations of technological diversification among Stone Age hunter-gatherers, and for tracking continuity and change in cultural traits through time and space. One prominent example is the many efforts to map the spatiotemporal diffusion of pressure blade technology. In this context, a key concern is to distinguish the various knapping techniques, applied by prehistoric knappers. Specific observable blade attributes, found by experimental work is proposed to provide essential information, to determine the technique used. To date, however, the causal relationship between blade knapping techniques and postulated technique-related attributes remains largely untested in quantitative terms. With the purpose of contributing to a better understanding of how various knapping techniques, and in this case the indentor type used for blade removal, effect particular aspects of blade morphology, statistical analysis of experimental data is used, and subsequently applied as a basis for predicting knapping techniques in blade assemblages from Early and Middle Mesolithic (ca. 9500-6300 cal. BC) Southern Norway. The results clearly indicate a considerable overlap in the distributions of the majority of the attributes with regards to technique, and that their causal relationship should be viewed with considerable caution. The discriminate capability increases, however, when specific composite attributes are considered. Importantly, what is also shown is that at the blade population level, results from statistical analysis of experimental data contribute to predict general tendencies in knapping technique variability in archaeological blade assemblages, while simultaneously formalising the discriminating characteristics that differentiate those assemblages. Taken together, these results have implications when investigating variation and change in blade technology in time and space.