Prior experience mediates the usage of food items as tools in great apes (Pan paniscus, Pan troglodytes, Gorilla gorilla, and Pongo abelii).

Humans use tools with specific functions to solve tasks more efficiently. However, functional specialization often comes at a cost: It can hinder the production of actions that are not usually performed with those tools, thus resulting in a fixation effect (functional fixedness). Little is known about whether our closest living relatives, the nonhuman great apes, are vulnerable to this detrimental effect of experience. We examined whether great apes from 4 species (