Chimpanzees conform to cultural norms

Whiten, A., Horner, V., & de Waal, F. B. M. (2005). Conformity to cultural norms of tool use in chimpanzees. Nature, 437, 737-740. doi:10.1038/nature04047

Georgia pokes the block while a group member watches.

This study mimicked the spread of different cultures in each of the two Field Station chimpanzee groups. The chimpanzees were presented with a puzzle box called the ‘Pan-pipes’ that contained a food reward trapped behind a small square block in a series of pipes. One chimpanzee from each group was shown how to use a stick to retrieve the food using one of two different techniques. In FS1, Georgia was trained to poke the block, pushing it so that the food fell backwards and rolled down another pipe into her waiting hand. In FS2, Ericka was trained to lift the block, so that food fell forward and into her hand. Ericka and Georgia were then reunited with their respective groups and soon started to apply their newly-learned techniques to the Pan-pipes task, observed by other chimpanzees. When observers had a chance to solve the task, they were successful, and predominantly used the technique that they had seen. This study suggests an ancient origin for the propensity to cultural conformity, which until now was thought to be unique to humans.