Analysis of wild macaque stone tools used to crack oil palm nuts.

The discovery of oil palm () nut-cracking by wild long-tailed macaques () is significant for the study of non-human primate and hominin percussive behaviour. Up until now, only West African chimpanzees () and modern human populations were known to use stone hammers to crack open this particular hard-shelled palm nut. The addition of non-habituated, wild macaques increases our comparative dataset of primate lithic percussive behaviour focused on this one plant species.