Like humans, chimps can warn others of impending trouble
Los Angeles Times
Chimpanzees adjust their warning calls if they think a fellow primate hasn’t picked up on a nearby threat, a new study finds.
The results, published in the journal Science Advances, reveal that humans and one of their closest living relatives may share a very special ability, one that could potentially shed light on the origins of language.
Humans have succeeded as a species in large part because of our complex social communication skills—and underlying those skills is the ability to understand another individual’s perspective, and adjust what we say accordingly.
“In humans there’s a strong convention, if I’m talking to you I should generally tell you things you don’t already know,” lead author Catherine Crockford, a primatologist at Max Planck Institute for Evolutionary Anthropology in Germany, said in an email. “Right now, if I tell you things you know already, you’d probably get impatient quite quickly.”
But when an animal makes a call, does it know what its peers know or don’t know? Or is it just expressing its own internal feelings?
“There’s an assumption though, that animals don’t do this,” Crockford said. “Take alarm calls. Lots of animals give alarm calls. If a monkey gives an alarm call to a snake, it’s thought to be purely motivated by the signalers’ own perspective, like their own state of arousal, their own emotional state.”
Plenty of mammals have been spotted adjusting their calls according to context and other members’ behaviors. For example, harem male monkeys sound the alarm more when members of their group are close to a threat and only stop after those members have also called out an alarm. Studies show that chimps are more likely to alarm call when their peers haven’t seen the threat or heard the threat-related calls, and may quiet down after those peers have made it to safety, the researchers pointed out.
The findings could help scientists better understand the roots of language and communication in humans, she added.