Apparently “chimps are subject to contagious yawning”:http://www.newscientist.com/news/news.jsp?id=ns99996182 just like humans.
_The team played videos of chimps either yawning or exhibiting other open-mouth behaviours such as grinning to six adult chimps and three infants at the Primate Research Institute of Kyoto University in Japan._
_…They argue that their figure of 33 per cent of adults showing contagious yawning compares well with humans since the chimps do not understand the purpose of the trial._
_…”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._
I’ll be impressed when chimps read this story and start to yawn, as I did. Contagious yawning always been a fascinating phenomenon for me, but I’d say the fact that it can be triggered by reading or thinking about it means that it’s a little deeper (psychologically) than just a social cue.
I’ve been curious about how the relationship with the yawner mediates the effectiveness of inducing a yawn in another. My girlfriend Sabrina has a considerably more effective ability to pass yawns to me (and I seem to have a similar effect on her) than other friends of mine, and these more than does a stranger near me.
Perhaps this perception is related to the amount of overall time spent with a yawner and there really is no mediation. Or maybe we’re just both suggestible and yawn a lot, too.