We already know that yawning is highly contagious and, in humans and other primates, may be rooted in empathy. Human-dog yawning contagion is well known too, as previously shown in Metafilter, but its causes are contradictory, as yawning in dogs is also associated with psychological tension or mild stress. A new study confirms that dogs yawn more frequently when watching their owner than when watching a stranger, demonstrating that the contagiousness of yawning in dogs correlates with the level of emotional proximity, possibly indicating rudimentary forms of empathy in dogs.
TV's Mythbusters, (and as such Metafilter's 'very own' asavage), hopes to use the global reach of Youtube to send a yawn around the world. "If only one per cent of the global population took part in the Yawn Around The World experiment then 65 million people would have yawned across the globe" Savage was quoted as saying. The equivalent amount of air exhaled would "be able raise the Titanic or even inflate all the bicycle tyres in Beijing." Fascinating stuff! Watch the (hopefully) yawn inducing footage here.