Out of sight may not equate to out of thought for our simian counterparts

In a significant breakthrough for cognitive psychology, a bonobo named Kanzi has shown the ability to mentally track multiple familiar humans even when they are out of sight. This remarkable feat was demonstrated by a study led by Johns Hopkins University's Social and Cognitive Origins Group and published in Proceedings of the Royal Society B.

The study, supported by the Templeton World Charity Foundation and the CIFAR Azrieli Global Scholars Program, was conducted in a controlled environment. Kanzi was presented with two caregivers who hid behind barriers, while photos of the caregivers were shown to him. He was then asked to point to the location of the caregiver depicted in the photo.

Chris Krupenye, an assistant professor at Johns Hopkins who studies animal cognition, believes that this study suggests that apes might have the foundations of our rich social intelligence. Kanzi's performance was above chance, especially well with one of his caregivers, indicating a strong understanding of the task.

Kanzi's memory of individuals brings together their vocal and visual identities. The team also tested if Kanzi could identify caregivers by their voices, a capacity previously untested in bonobos. The results demonstrated that Kanzi could hear which caregiver was behind each barrier and point to their location correctly.

This study answers key questions about how animals manage to keep track of their groupmates and uncovers yet another aspect of human social cognition shared with our closest relatives. Chimpanzees have been shown to recognize the faces and vocalizations of familiar groupmates, even after years apart, and have been observed to recognize familiar humans, even when they had masks on, in field studies.

The team hopes to test the boundaries of how many individuals apes can mentally track at once and how long those memories last. This research could provide valuable insights into the evolution of social intelligence and the shared cognitive abilities between humans and our closest relatives.