Watch Kanzi the bonobo pretend to have a tea party

Such studies have nevertheless been met with skepticism when it comes to interpreting the behavior as evidence of animals’ ability to pretend. For example, it is possible that animals respond to behavioral cues, such as gaze direction, to solve such tasks.

“Kanzi, let’s play a game!”

Enter Kanzi, a 43-year-old bonobo who lives at the Ape Initiative and is able to respond to verbal prompts, either by pointing or using a lexigram of more than 300 symbols. There have also been anecdotal sightings of Kanzi faking it. Krupenye et al. conducted three separate experiments with Kanzi, each involving a session of 18 trials.

In the first experiment, a scientist offered a verbal prompt: “Kanzi, let’s play a game! Let’s find the juice!” They then placed two empty transparent cups on a table and pretended to fill them from an empty transparent pitcher, with another verbal prompt (“Kanzi, look!”). The scientist pretended to pour the “juice” contained in one of the cups into the pitcher, placing the pitcher under the table. Then they asked: “Kanzi, where is the juice?” and recorded which cup the bonobo pointed to first.

“If Kanzi could only follow reality (that both cups were empty), he should have chosen randomly between the two options, whereas if his choices were guided by stimulus enhancement, he would have had to select the wrong cup that had been ’emptied’ above chance,” the authors wrote. “On the other hand, if Kanzi could represent the fake juice, he would have had to randomly choose the cup containing the ‘imaginary’ juice, the empty cup that had not been ‘poured’ into the pitcher. That’s exactly what Kanzi did.” Kanzi selected the correct cup 34 out of 50 times (68%).