Hand grasping and finger flexion during Lower Paleolithic stone tool ergonomic exploration

Abstract

Lower Paleolithic stone tool features and shape have been studied in detail; traceology and experimental archaeology have provided us with a lot of information about possible tool use and functionality. The way modern humans use these tools has been used as a proxy for the study of early stone tool-makers’ behavior, taking into account that our ancestors could have had similar manipulative capabilities to us. Less importance has been given to stone tool ergonomics, even if comfortable and ergonomic grasping prevent hand damage and improve tool use. Here, we measured the phalanx flexion of 82 subjects during comfortable stone tool handling for both Oldowan pebble tools and Acheulean handaxes. We expected differences in the pattern of phalanx flexion in the two tool types and in relation with tool dimensions. In fact, Oldowan pebble tools and handaxes show differences in finger flexion and in the single finger contribution to comfortable grasping.