Social tolerance and success-biased social learning underlie the cultural transmission of an induced extractive foraging tradition in a wild tool-using primate

The last two decades have seen great advances in the study of social learning (learning from others), in part due to efforts to identify it in the wild as the basis of behavioral traditions. Theoretical frameworks suggest that both the dynamics of social tolerance and transmission biases (or social learning strategies) influence the pathways of information diffusion in social groups. Bearded capuchins ( Sapajus libidinosus ) inhabiting the semiarid seasonal caatinga biome of the Serra da Capivara National Park (SCNP) form highly tolerant societies that possess the largest “tool-kit” described for monkeys, a feat likely facilitated by social learning. Here, we used social network analysis and an open diffusion experiment using an extractive foraging task to identify the occurrence of social learning and describe the pathways of social transmission of information in two wild primate populations. The dynamics of social tolerance outside of task introductions predicted opportunities for social learning, but it was tolerance during task introductions that predicted the actual pathways of social information diffusion. Our results also indicated that the capuchins mainly learned from others via direct observation and naïve individuals exhibited an observation bias toward successful males. This study supports the claims of cultural transmission in robust capuchins and empirically supports the role of social tolerance and social learning strategies in human and nonhuman primate cultural evolution.