Perhaps it is not very surprising that this cognitive skill level of theory of mind can be found among the closest relatives of humans bonobos. Recently, researchers have confirmed that these animals understand the state of others, especially when people are ignorant in matters where those bonobos know.
Researchers at Johns Hopkins University performed their experiment at the Ape Initiative research center in Iowa in a study that tested whether bonobos can determine when an experimenter is unaware of important information. This was based on the chance to help an experimenter find hidden food based on what the apes had seen. Three male bonobos were used for this study.
A treat was placed under one of three cups on a table in the experiment. In the “knowledge condition,” the experimenter could see where the treat was hidden. In the “ignorance condition,” a barrier blocked their view. If the experimenter successfully found the treat, they would reward the bonobo, creating a motivation for the apes to share their knowledge.
Over 24 trials per condition, researchers found that bonobos pointed to the right cup 20 percent more often and did so 1.5 seconds faster when someone else was ignorant. This suggests that bonobos understand when another person is lacking information and behave accordingly, says co-researcher Christopher Krupenye.
This suggests that they do something if they find out that someone perceives something from a different viewpoint than theirs,” Krupenye said. The results supported earlier observations on wild chimpanzees, who have been documented to raise others’ awareness of potential threats like fake snakes scientists placed in the environment.
The results of the study provide controlled experimental evidence for the notion that bonobos, and probably other great apes, have elements of the theory of mind. But Zanna Clay, a primatologist at Durham University, warns that the findings may not be generalizable to all bonobos because the subjects of this study were raised in human-oriented environments.
This skill may have, therefore, contributed significantly to the survival and even cooperation of our early human ancestors with bonobos, she adds. Critical information such as food locations shared between individuals was crucial for human survival.
She further states, “This discovery debunks centuries-old assumptions on non-human intelligence, which again brings us one step closer to bridging this cognitive gap that separates humans and their evolutionary cousins.”.
