Bonobos keep track of groupmates even when they can’t see them, study finds

Kanzi, a bonobo celebrated for his intelligence, died in March this year. A recently published study adds to his long list of cognitive abilities: he was able to track the location of people familiar to him, even when they were out of sight. He could also recognize the individual voices of his caretakers, a skill that has never before been tested in bonobos (Pan paniscus). Kanzi was 44 years old when he died. He lived much of his life at the Ape Cognition and Conservation Initiative in Des Moines, Iowa. For the latest study, conducted in 2023, researchers set up a barrier with three panels and had two caretakers familiar to Kanzi hide behind them. An experimenter held up a photo of each hiding caretaker and asked Kanzi to point to the panel where they were hiding. Kanzi got the answer righ