Children's use of social information from multiple models: Cognitive capacities underlying population size effects on cumulative culture

Population size has been proposed to promote cumulative culture in humans. Experimental evidence from adult humans suggests that one explanatory mechanism might involve combining beneficial information from multiple models. However, it is possible that such combinatory social learning requires cognitive capacities restricted to adult humans. In our task, children aged 5–10 were exposed to two models who consecutively searched a 3×3 array for rewards. Models revealed different correct and incorrect reward locations. This information could be used by the child to maximise their own score on the same task. We were interested in children's ability to select rewarded locations, and avoid unrewarded ones, revealed by both models. We also manipulated the spatial and temporal displacement of the information available. Results showed that the youngest children were unable to fully benefit from the additional information provided by the two models under spatial and/or temporal displacement. Such displacement likely applies in most real-world cases of cumulative culture therefore our result may offer insight into the constraints on cumulative culture in nonhumans.