New research compiled by the University of Portsmouth shows that sun bears – the world’s smallest species in the bear family – use facial expressions to show when they want to play with one another.
The bears tend to prefer a solitary life, but have now been seen opening their mouths to match their playmates when they are interacting face-to-face.
It comes after 22 sun bears were studied by the university at the Bornean Sun Bear Conservation Centre in Malaysia.
In total, 21 matched the open-mouthed expressions of their playmates during face-to-face interactions.
When they were facing each other, 13 bears made expressions within one second of observing a similar expression from their playmate.
Dr Marina Davila-Ross, from the University of Portsmouth, said the findings suggest the behaviour is exhibited outside humans and apes and could be more widespread in mammals.
‘Mimicking the facial expressions of others in exact ways is one of the pillars of human communication,’ she said.
‘Other primates and dogs are known to mimic each other, but only great apes and humans were previously known to show such complexity in their facial mimicry.
‘Because sun bears appear to have facial communication of such complexity and because they have no special evolutionary link to humans unlike monkeys are apes, nor are they domesticated animals like dogs, we are confident that this more advanced form of mimicry is present in various other species.’