Chimpanzees yawn in response to seeing other chimps yawn, reveals a new study. The discovery bolsters the idea that chimps are able to understand their own and others’ state of mind.
There is more:
In research on people, those subjects that perform contagious yawning also recognise images of their own faces and are better at inferring what other people are thinking from their faces. What is more, brain imaging studies have shown that people watching others yawning have more activity in parts of the brain associated with self-information processing.
“Our data suggest that contagious yawning is a by-product of the ability to conceive of yourself and to use your experience to make inferences about comparable experiences and mental states in others,” Gallup told New Scientist.