Movement Pattern Variability in Stone Knapping: Implications for the Development of Percussive Traditions

Abstract

The earliest direct evidence for tool-use by our ancestors are 2.6 million year old stone tools from Africa. These earliest artifacts show that, already, early hominins had developed the required advanced movement skills and cognitive capacities to manufacture stone tools. Currently, it is not well understood, however, which specific movement skills are required for successful stone knapping and accordingly it is unknown how these skills emerged during early hominin evolution. In particular, it is not clear which striking movements are indicative of skilled performance, how striking movement patterns vary with task and environmental constraints, and how movement patterns are passed on within social groups. The present study addresses these questions by investigating striking movement patterns and striking variability in 18 modern stone knappers (nine experienced and nine novices). The results suggest that no single movement pattern characterizes successful stone knapping. Participants showed large inter-individual movement variability of the elementary knapping action irrespective of knapping experience and knapping performance. Changes in task- and environmental constraints led knappers to adapt their elementary striking actions using a combination of individual and common strategies. Investigation of striking pattern similarities within social groups showed only partial overlap of striking patterns across related individuals. The results therefore suggest that striking movement patterns in modern stone knappers are largely specific to the individual and movement variability is not indicative of knapping performance. The implications of these results for the development of percussive traditions are discussed.

Experimental studies illuminate the cultural transmission of percussive technologies inHomoandPan

“…Although there is a long tradition of experimental (often described as 'actualistic') approaches to knapping per se, there exist only a handful of such experiments applied specifically to social learning of the skills involved, with just two substantial studies published very recently [10,11] and discussed in some detail below ( §6a,b). A larger corpus of studies relevant to this topic includes those comparing novice and expert percussive skills [64], covering both nutcracking and stone knapping [65]; identifying concordances in the knapping of novices and experts working in different sub-groups [66]; establishing the material artefact correlates of degrees of skill [67]; and longitudinal studies of skill development [68]. This larger literature is regrettably beyond the scope of this article but is referred to elsewhere in this Issue by the several papers focused on hominin knapping.…”

Individuals Among the Pots: How Do Traditional Ceramic Shapes Vary Between Potters?

“…In fact, the role of the tutor is only to guide the novice. Executing a technical movement implies a mixture of common and individual strategies (Parry, Dietrich, & Bril, 2015;Reed & Bril, 1996;Rein, Nonaka, & Bril, 2014). This explains that, despite belonging to the same learning network, the potters produced traditional ceramic shapes whose metric variability corresponds to individual signatures.…”

The manual pressures of stone tool behaviors and their implications for the evolution of the human hand

“…All subjects had no prior experience making or using stone tools. Although previous work has shown substantial interindividual variation in the kinematics of the upper limb during stone tool knapping within both novice and expert knappers (Rein et al, 2014), we include only novice participants to help reduce two confounding effects: (1) variation in skill for any given behavior among participants, and (2) variation in the skill possessed by a single participant among all tested behaviors. Data were collected from participants who provided informed consent under a protocol approved by the Institutional Review Board of Chatham University.…”