CNN
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Chimpanzees living in sanctuaries in Africa have developed “fashion trends” for blades hanging from ear holes and grass and sticks from behind, new research shows.
In 2010, researchers working at the Trust Chimpanzee Reserve at the Chimhunsi Wildlife Orphanage in Zambia observed how female chimpanzees began hanging objects from her ears.
There is no evidence that chimpanzees were dealing with pain and itching using grass or sticks, and when they did it they were “very relaxed,” Van Leewen said.
Action is like “fashion trends or social traditions.”
Interestingly, chimpanzees from another group of Sanctuary began to demonstrate the same behavior over a decade later.
The group lived about nine miles from the first group, so they were unable to copy it from them, urging Van Lewen to ask if the chimpanzee caregivers had influenced them.
After all, staff in one area of the reserve had developed the habit of cleaning their ears with matchsticks and twigs, but the staff on the other side did not.
Van Lewen believes that the behavior was picked up by chimpanzees from the first local caregiver before being handed over to other members of the group.
Caregivers subsequently also influenced the behavior of the second group. This group was watching a few years later, but the group also developed a practice of inserting rods and grass into the rectum.
“This is a tendency to get viral due to social learning,” he added.
Van Lewen also cited an example of a group of chimpanzees at a Dutch zoo.
Soon, he said all women adopted this walking style. Furthermore, when two new women were brought into the group, the women who quickly adopted the style were quickly integrated, while those who refused to walk in the group style took longer to be accepted.
For Van Leeuwen, these actions, like humans, are to adapt and smooth social relationships.
Grass behavior was observed mostly in leisure time when chimpanzees gathered to play with the groom.
Chimpanzees who live in sanctuaries do not need to worry about competing with predators or other groups. This means that he has more leisure time than his wild counterparts.
“They have time to hang out,” Van Lewens said.
Nevertheless, wild chimpanzees are likely able to develop such behavior, he said, adding that it may not be documented yet.
Next, Van Leeuwens will be studying whether chimpanzees can repeatedly innovate new foraging techniques and whether they can develop cumulative cultures in the same way as humans.
Elody Freyman, a post-doctor affiliate for primate models at the University of Oxford Behavioral Evolution Lab, was not involved in the study, but told CNN that these types of observations are key to advancing understanding of the origins and patterns of transmission of cultural behavior in chimpanzees and other non-Human animals.
“The finding that this study could have had interspecies copies between chimpanzees and their human caregivers is quite heart-blowing,” she said.
“If chimpanzees can copy humans, can they learn and copy other non-human species? That’s an exciting primate moment,” added Freyman.
