Abstract

Theoretically, object play is thought to facilitate the acquisition and expression of tool use; empirically, evidence for this claim is limited. We examined whether a form of culturally maintained object play, named stone handling, characterized by high interindividual variation in its behavioural expression, promotes the acquisition and further expression of stone-tool use in a free-ranging group of Balinese long-tailed macaques. Using a combination of observational and experimental methods, we tested whether individual stone-play profiles predicted monkeys’ ability to solve foraging tasks using stones as tools. Our results suggest that stone-tool-assisted foraging relies on various social and asocial learning strategies. Certain stone-play profiles, as well as other trait- and state-dependent variables, contributed to explaining the variance observed in stone-tool use in this population. The behavioural idiosyncrasies associated with stone-play in long-tailed macaques may serve as an exaptive reservoir for the possible emergence of stone-tool use. These findings shed light on the potential ecological and evolutionary implications of early human lithic technology.

About the speaker

Camilla Cenni, School of Social Sciences, University of Mannheim

Free of charge - All are welcome