The world’s smallest bear has joined an elite list of species known to mimic the facial expressions of others during social interactions.
Which is all the more surprising given that sun bears are pretty unsociable creatures and largely solitary in the wild. In captivity, though, they are rather playful.
“Prior to carrying out the study, we observed a few times that the sun bears rapidly matched their play faces during social play,” says Marina Davila-Ross from the University of Portsmouth.
This prompted a study of captive animals in Malaysia, and the team found that the bears would often respond to a playmate changing its expression within just one second. Facial mimicry is found in humans, a few other primates, and domestic dogs. But the bears were seen to do it with a precision only found in humans and gorillas.
“Because sun bears appear to have facial communication of such complexity, and because they have no special evolutionary link to humans, like monkeys or apes do, nor are they domesticated animals like dogs, we are confident that this more-advanced form of mimicry is present in various other species,” says Davila-Ross.
The biologists suggest the behaviour might help ensure that a bout of rough-and-tumble does not escalate to full-blown hostility.