How 8 years of social and individual learning interact to shape ecological competence in orangutans.

Cultural learning permeates human skill and knowledge acquisition. To understand its importance for nonhuman apes, we analyzed just under 7000 records of behavioral bouts of social and individual learning across wild orangutans' 8-year dependency period to assess their combined effects on ecological competence, which is crucial for independent survival. Social learning was five times more frequent than individual learning and influenced subsequent learning for hours. Immature orangutans varied substantially in their learning propensities, and those with heightened social and individual learning propensities developed the most expansive diet profiles at independence. Furthermore, social learning had a compensatory effect on diet profile development when individual learning was low. Our findings advance the science of cultural evolution by showing how multiyear social and individual learning interact to shape great apes' broad ecological competence.