This Bonobo Just Did Something Scientists Thought Only Humans Could Do

Kanzi participated in three carefully designed experiments modeled after children's tea parties, where he was asked to track and identify imaginary objects like pretend juice and grapes. In these experiments, researchers would pretend to pour juice into a cup or place grapes in a bowl, then move the cup or bowl to different locations. Kanzi was then asked to point to where the pretend object was located. He consistently and reliably pointed to the correct locations of these imaginary items, demonstrating that he could mentally track objects that weren't physically present. Importantly, when given the choice between real food and pretend food, Kanzi still chose the real food, showing he understood the distinction between what was real and what was imaginary.

This discovery challenges the long-held scientific belief that imagination and pretend play are uniquely human abilities. Prior evidence of pretense in apes only showed solitary enactments—such as an ape holding a stick like a pretend offspring—but this study provides the first experimental evidence that apes can engage in shared pretense with another individual and track imaginary objects across different locations. The findings suggest that the capacity for secondary representations (the ability to conceive of things that aren't physically present) is not exclusive to humans. This indicates that apes can think more flexibly than previously assumed and may possess more sophisticated cognitive abilities related to imagination, future-oriented thinking, and understanding what others might be thinking. The research opens new avenues for investigating whether other animals also possess these mental abilities.