Science Friday

What A Tea Party With A Bonobo Taught Us About Imagination

February 13, 2026

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  • Experiments involving Kanzi the bonobo demonstrated that the capacity to imagine, previously thought to be uniquely human, may be shared by other species, as Kanzi successfully tracked imaginary displacements during a pretend tea party. 
  • Kanzi's willingness to engage in the pretend tea party experiment without direct reinforcement suggests an intrinsic enjoyment or understanding of the imaginative scenario, challenging previous assumptions about animal cognition. 
  • The study on Kanzi reinforces a recurring pattern in cognitive science where abilities once defined as uniquely human (like tool use or, in this case, imagination) are later shown to be present in other animals, continually shifting the definition of 'humanness'. 

Segments

Introduction to Imagination Study
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(00:00:33)
  • Key Takeaway: Imagination, long considered a uniquely human trait, is being investigated in bonobos through controlled experiments.
  • Summary: The Science Friday episode introduces the concept that imagination might not be exclusive to humans. Scientists conducted experiments involving pretend tea parties with a bonobo named Kanzi to test this capacity. Producer Kathleen Davis interviews study author Dr. Amalia Bastos about the findings.
Origin of Kanzi’s Tea Party
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(00:01:27)
  • Key Takeaway: Kanzi initiated the line of research by spontaneously requesting researchers to engage in pretend play, specifically asking them to tickle and chase each other.
  • Summary: The study’s inspiration came directly from Kanzi, who used his lexigram to request researchers perform actions like tickling each other. This initial interaction led the research group to wonder if apes possess the capacity for pretense.
Pretend Tea Party Methodology
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(00:02:53)
  • Key Takeaway: The experimental design adapted methods used to prove pretend play in human toddlers, focusing on tracking the displacement of imaginary liquids.
  • Summary: Researchers adapted a method used on two and three-year-old children: pretending to pour imaginary juice (substituted for tea, which Kanzi dislikes) into cups and then asking Kanzi where the imaginary juice remained after one cup was emptied. Kanzi correctly identified the location of the imaginary juice more often than expected by chance.
Controlling for Bias and Confusion
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(00:04:47)
  • Key Takeaway: The study controlled for participant bias using a Naive Experimenter design and confirmed Kanzi understood the difference between real and fake juice in a follow-up test.
  • Summary: To rule out Kanzi merely guessing or trying to please the researchers, the experimenter running the procedure was naive to the study’s hypotheses. A second experiment confirmed Kanzi could distinguish between real and fake juice, proving he was not confused but rather engaging in the pretense.
Kanzi’s Engagement and Passing
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(00:06:58)
  • Key Takeaway: Kanzi consistently engaged in the non-reinforced imaginative trials, indicating enjoyment, but passed away before researchers could test if he could initiate imaginary scenarios himself.
  • Summary: Kanzi continued participating in the trials even though he received no reinforcement for correct choices, suggesting he enjoyed the activity. The research was tragically cut short as Kanzi passed away in March 2025 before the next logical step—testing if he could host his own imaginary tea party—could be investigated.
Imagination in Other Animals
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(00:07:42)
  • Key Takeaway: Anecdotal evidence suggests other apes engage in pretend behavior, such as chimpanzees carrying sticks as infants, but empirical testing is necessary to differentiate pretense from simple mistake.
  • Summary: Previous observations include chimpanzee females carrying sticks as if they were infants, but these lack empirical verification. Testing imagination in other species is difficult because it requires methods that ensure the animal understands the task is one of pretense, often necessitating language prompting.
Evolutionary Benefit of Pretend Play
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(00:09:21)
  • Key Takeaway: Imagination likely serves an evolutionary function by allowing juveniles to prepare for future real-world risks and social situations without facing actual consequences.
  • Summary: Pretending allows individuals, like human children or young apes, to practice future actions, such as caring for infants, without any real-world risk. This rehearsal mechanism prepares them for necessary future behaviors when the stakes are real.
Impact on Human Uniqueness
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(00:11:13)
  • Key Takeaway: Discoveries like Kanzi’s imagination challenge the tendency for humans to define themselves by abilities later found in other species, such as tool use.
  • Summary: The research reflects a pattern where abilities once thought to be uniquely human, like tool making (disproven by Jane Goodall’s work with chimpanzees), are shown to be shared. Each such finding forces a re-evaluation of what truly differentiates humanity from other animals.