We all know yawning is contagious – you don't even want to know how many times I yawned just writing this – but can yawning actually tell us something about our relationships? A 2011 study from the University of Pisa found that your yawns are most contagious to those you're close to, including family members, close friends, and romantic partners.
Timing is crucial here. Researchers at the University of Pisa found that your yawns will be returned more quickly by those closest to you. In fact, the study even found that the timing of yawn transmission changes according to relationship: your family will respond to your yawns the quickest, then friends, then acquaintances, and lastly strangers. So what should you think if your lover doesn't yawn after you?
Sam Kean, who writes about yawning (among other things) in his upcoming book The Tale of the Dueling Neurosurgeons, wonders “if you could tell someone was falling out of love with you by timing their yawn delay.” Let's be real here, timing your partner's yawn sounds sort of like some far-fetched Cosmo tip. But next time you're tired and your partner starts yawning along, at least you'll know it's love, not boredom.