Overview
- The paper, published February 5 in Science, reports that Kanzi followed make-believe juice and grapes in staged tea‑party tasks designed from child‑development research.
- Kanzi identified the location of pretend juice 34 out of 50 times (68%), chose real over pretend juice 14 out of 18 times (~78%), and tracked an imaginary grape correctly in about 69% of trials.
- Researchers modeled the experiments on paradigms that probe secondary representation, indicating Kanzi kept imaginary and real states in mind at once.
- Kanzi was a highly enculturated, lexigram‑trained bonobo who died in March 2025 at age 44, a background the authors and outside experts say limits how far the findings can be generalized.
- Several scientists praised the work as the first experimental evidence of nonhuman pretend‑object representation, while critics urged tests with less‑enculturated apes and noted alternative explanations; the authors suggest the roots of such capacities could date to the human–bonobo common ancestor 6–9 million years ago.