Is Human Handedness Universal? Ethological Analyses from Three Traditional Cultures

Abstract

Right‐handedness in Homo sapiens is claimed to be qualitatively different from that of other primates, at species level, and to be universal across all cultures. Ethnographic indicators are sparse, however, being mostly indirect rather than direct observations of selected motor patterns. Ethological study of hand use, i.e. observation of a wide range of everyday behavioural patterns performed spontaneously, is missing. We coded such manual activity from cinematic archives of three traditional societies: G/wi San of Botswana, Himba of Namibia and Yanomamö of Venezuela. Results showed a consistent but weak right‐hand dominance across these three preliterate cultures. Most individuals showed mixed‐, rather than right‐handedness, irrespective of whether or not object manipulation was involved. The notable exception was tool use, which was markedly right‐handed, and only precision‐gripping tool use was normally performed exclusively with the right hand. Most questionnaires that measure handedness focus on precision tool use (and so are likely to be biased accordingly) rather than on more comprehensive ethological measures that include non‐object‐manipulatory, self‐directed and socially communicative patterns of behaviour.