Social learning of nut-cracking behavior in East African sanctuary-Living chimpanzees (Pan troglodytes schweinfurthii)

Nut cracking is restricted to communities of wild chimpanzees living in West Africa, suggesting it is an example of a socially transmitted tradition. Detailed study of the acquisition of nut cracking in wild chimpanzees is consistent with this conclusion. However. only 2. small-scale experiments have been carried out in captivity to explore the role of social transmission in the acquisition of this behavior. The study presented here does this with a comparatively larger, statistically viable sample of 11 sanctuaryliving chimpanzees (Pan troglodytes schweinfurthii), permitting both between- and within-subjects experimental manipulations. Results confirmed that nut cracking can be acquired in a matter of days by social learning, but only in chimpanzees 3 to 4 years old and older. Direct comparisons are made with a study carried out in the wild, revealing striking similarities in developmental profiles. Keywords: tool use, social learning, nut cracking, chimpanzees