Bonobos who haven’t seen their sisters or nephews for decades still recognize their faces. This is evidenced by the research published on Monday in the scientific journal Proceedings of the National Academy of Sciences.
The researchers worked with chimpanzees and bonobos in reserves in Europe and Japan. Scientists used eye trackers and infrared cameras. They used this to map the apes’ gaze as the animals looked at pictures of their own kind.
Some of those photos were of complete strangers. Other photos were of close friends, family members or enemies they had not seen in years.
The animals looked longer at pictures of monkeys with whom they had a positive relationship, such as former groupmates who had taken care of them or played with them. They spent less time looking at the faces of previous sexual partners, distant acquaintances, or monkeys who had hurt or frightened them.
This admission is consistent with similar studies conducted on children. “It’s like meeting someone on the street you haven’t seen in years, and you do a double take to get to know them,” says the lead researcher.
Ontvang meldingen bij dierennieuws
Identifying enemies is crucial
“It’s a fantastic result,” says primatologist Frans de Waal of Emory University, who was not involved in the study. “I’m not even sure people remember most of the people they haven’t seen in 20 years.”
However, this is not surprising, researchers believe. Recognizing friends and enemies by their appearance is crucial to human survival. In addition, animals such as dolphins, elephants, and dogs are known to use sounds or smells to recognize another individual.
But according to de Waal, research shows that other animals may also remember a lot more than we think.