The spatial properties of forager motion categories: Evidence from Jahai

There is a growing appreciation of the need and urgency to study and document mobility and energetics among extant hunter-gatherers. An increasing number of studies investigate the spatial and biophysical properties of hunter-gatherer movement, in order to gain a deeper understanding of such things as human energy expenditure and efficiency in human foraging behavior. So far, however, this research has not set out from representations of motion as expressed by the communities themselves. Such representations, as manifested in language for example, may provide significant clues to strategies of mobility of relevance. Here we conduct a first spatial investigation into indigenous hunter-gatherer representations of motion as they unfold in the landscape during foraging trips on foot. Specifically, we record using GPS and explore in a Geographical Information System the real-world instantiations of a set of cross-linguistically unusual motion verbs in the language spoken by the Jahai, a group of subsistence foragers in the mountain rainforests of the Malay Peninsula. We analyze these verbs in a Digital Elevation Model and show that their usage and meanings are directly connected to features and properties of local topography, notably gradient. Such meanings are unexpected by current semantic theory. We conclude that the verbs are highly motivated by the affordances and interactional properties of the terrain, and are relevant to both foraging strategies and energy expenditure on the move. Our results underscore the significance of intangible indigenous representations as an informative inroad into human spatial behavior, and the potential of GIS in exploring them.