From Crocs to bleached eyebrows, we’re no strangers to bizarre and pointless social fads.
But humans aren’t the only primates who like to keep up with the latest trends.
Chimpanzees living in a wildlife sanctuary in Zambia have started wearing grass or sticks in their ears.
Hilarious images show the fashion-forward chimps taking part in the latest craze.
The researchers behind the discovery say that the group weren’t doing this for any practical reason, such as to relieve a hard-to-reach itch.
Instead, the impractical habit has spread as a purely social trend.
Dr Jake Brooker, a primatologist at Durham University and co-author of the study, says: ‘What’s remarkable is that these customs have no obvious utility.
‘This isn’t about cracking nuts or fishing for termites – it’s more like chimpanzee fashion.’
Chimpanzees at a wildlife sanctuary in Zambia have started wearing pieces of grass in their ears in a bizarre trend
Chimpanzees are exceptionally adept at spreading new techniques and skills through social learning.
This allows them to acquire complex skills that help them survive, just by watching others.
However, scientists are now beginning to show that chimpanzees also pick up habits that are totally useless.
In 2010, keepers at the Chimfunshi Wildlife Orphanage, Zambia, spotted that a female chimpanzee had started placing a piece of grass or stick in her ear.
Soon, all the chimpanzees in her social circle were doing the same, and the behaviour persisted even after the original trendsetter died.
Now, scientists have seen this same trend come back into fashion among chimps in the same sanctuary, despite not having been seen in over a decade.
Scientists from Durham University and Utrecht University observed 136 chimps split across eight groups.
In one of the tight-knit social groups, chimps suddenly started wearing grass in their ears.
Scientists say the habit has no practical purpose, such as scratching an itch, and is purely ‘chimpanzee fashion’
In a bizarre twist, some chimpanzees in the group even took to wearing pieces of grass or sticks in their behinds
Within weeks, five of the eight chimpanzees started wearing grass in their ears.
Meanwhile – in a bizarre twist – six even began inserting grass or sticks into their rectums.
Since this odd behaviour was not seen in any of the other chimpanzee groups, the scientists believe it is being spread socially like a trend spreading through a human school.
This practice might serve a social function, allowing chimps to show they are paying attention to other members of the group and strengthening social bonds.
‘It mirrors how human cultural fads spread: someone starts doing something, others copy it, and it becomes part of the group identity even if it serves no clear purpose,’ says Dr Brooker.
Based on their observations, the researchers think that the chimpanzees might have picked up this habit from their caretakers.
In interviews, the caretakers said they would sometimes use a blade of grass or a matchstick to clean their ears while out with the chimpanzees.
These caretakers only looked after the groups where the trend started, and none of the other groups’ caretakers said they did the same thing.
The chimpanzees might have picked up the habit after watching their caretaker clean their ears with a matchstick
The fact that this fashion serves no purpose shows that chimpanzees will pass on pointless habits, in a similar way to how human trends catch on and spread
Once the chimpanzees learned to put sticks in their ears, the researchers suggest that a few individuals might have figured out they could put them in another place as well.
However, what is really important about these observations is not how the specific trend started, but what it reveals about chimpanzees’ social lives.
This discovery might place the origins of ‘symbolic’ behaviour, and the seeds of human culture, farther back in the evolutionary past than had been thought.
That could allow a greater understanding of how human culture evolved and why modern humans behave the way they do today.
Dr Edwin van Leeuwen, a primatologist at Utrecht University and co-author of the paper, says: ‘Why they do exactly this particular thing, I’m not really concerned about. But them copying the behaviour from each other, that is the important insight.’
‘This shows that, like humans, other animals also copy seemingly pointless behaviours from one another, and that, in turn, may offer insights into the evolutionary roots of human culture.’
