This project  focuses on examining the conditions under which the intentional production and use of sharp stone tools, “flakes”, may have emerged in the human archaeological record. The innovation of these tools by early hominins is seen as a turning point in human evolution, allowing them to access high-value resources more efficiently, freeing up time to focus on aspects other than survival.

Since we cannot directly observe the primers of this innovation in hominins, other extant primate species can be studied as behavioural proxy models. This study looks at chimpanzees (Pan troglodytes), long tailed macaques (Macaca fascicularis) and robust capuchins (Sapajus sp.) in both the wild and captivity, as promising behavioural models for the innovation of flake manufacture and use.

All three species will be given baited puzzle boxes that require a sharp stone tool (a flake) to access and the materials to make them (i.e., hammerstones and cores). The subjects will be tested using two experimental paradigms (a scaffolded short-term protocol and a long-term baseline) providing them with different conditions to develop the target behaviour. By testing three taxa with the same experimental approach across environments, we will provide one of the most comprehensive overviews of the potential conditions and precursors priming the innovation of intentional flake manufacture and use in primates.