Kanzi the bonobo at the age of 43. Image courtesy of Ape Initiative
Joel Kontinen
Bonobos are our closed relatives and that they share the same
traits that we do.
Kanzi, a bonobo with exceptional language skills, took part in a make-believe tea party that demonstrated cognitive abilities never seen before in non-human primates. A bonobo that took part in a pretend tea party like those acted out by young children has shown that our closest primate relatives have the capacity for make believe.
Kanzi the bonobo (Pan paniscus) was born in the US in 1980
and died at age
44 in March last year. He spent most of his life at the Ape Initiative
in Des Moines, Iowa, where he was renowned for being able to communicate by
pointing at symbols on a board.
In the year before he died, Amalia
Bastos at the University of St Andrews, UK, and her colleagues ran a
series of experiments aiming to understand whether, along with his superior
language skills, Kanzi was also able to engage in what researchers describe as
“secondary representations”. This is the ability to imagine an alternative
reality and, in some situations, share that pretense with another individual –
a skill that humans develop at an early age.
At 2 to 3 years old, children can follow the movement of
imaginary liquid between containers and keep track of where the “tea” is or
isn’t, says Bastos. “That’s exactly the sort of context we presented to Kanzi
to test this ability in a non-human animal.”
In the first stage of the experiment, researchers pretended
to pour non-existent juice into two empty cups before pretending to empty one
of the cups and then asking Kanzi which one he wanted. More than two thirds of
the time, Kanzi chose the cup that hadn’t been emptied and still contained the
pretend juice.
“If Kanzi hadn’t conceived of ‘imaginary juice’ in the cups
throughout the study, he should have picked between the two cups at chance –
after all, they were both empty,” says Bastos.
Then the researchers placed an empty cup and
one containing juice on a table in front of Kanzi. He chose the cup
containing juice more than three quarters of the time. This test was to ensure
the bonobo could differentiate between real and fake juice.
For the third test, the team started by placing a real grape
into one of two cups; Kanzi selected the real grape every time. Then a pretend
grape was placed in each of two cups before one was emptied. Again, in over
two-thirds of attempts, Kanzi correctly chose the cup that still contained a
pretend grape.
Bastos says all of the team’s studies with great apes
are fully voluntary. “The fact that Kanzi stuck around and continued to engage
even in trials where he knew there would be no reinforcement says to me that he
must have at least enjoyed it a little bit.”
Source:
James Woodford 2026 Bonobo's pretend tea party shows capacity for imagination | New Scientist 5 February

