Several studies have tried to test whether 'yawn contagion' can spread from humans to our beloved canines -- and whether that means the dogs feel empathy.
This story starts with a 2008 paper in Biology Letters titled rather wonderfully, "Dogs catch human yawns." Well, actually it started when my cat yawned and then I yawned and I wondered if animals could pass a yawn to me like a fellow human could. Spoiler: there's no evidence that cats can cause you to yawn. My alternative yawn hypothesis for yesterday's false yawn contagion is that sleeping five hours a night causes me to yawn frequently and being a kitten causes my kitten to yawn frequently. Therefore, it is not surprising that we yawned in quick succession.
But anyway, back to the paper. Its authors, Ramiro Joly-Mascheroni, Atsushi Senju and Alex Shepherd were familiar with the literature about contagious yawning. And yes, there is a surprisingly rich literature about the phenomenon where one person yawning causes another person to do the same. Some conjecture that this is an empathic response because there is a relationship between "the susceptibility to contagious yawning and self-reported scores of empathy" and also because individuals on the autism spectrum do not catch yawns from other people.
But humans don't seem to be the only animals that feed off the emotions of others. Dogs, some argue, might feel something like empathy. So, if empathy causes contagious yawning and dogs appear to feel empathy for humans, then perhaps dogs can catch our yawns. After all, "Dogs are unusually skilled at reading human social and communicative cues," the authors point out. "They can follow human gaze and pointing, they can show sensitivity to others' knowledge states (e.g. indicating the location of a hidden toy more frequently to someone not involved in hiding it than to someone who did the hiding) and they are even able to match their own actions to observed human actions."
So, the intrepid scholars devised exactly the experiment you'd imagine. They sat a dog down in front of a human experimenter and had that person either A) yawn or B) make "non-yawning mouth-opening actions."
The existence of human-to-dog yawn contagion appeared to be settled. And more intriguingly, there was hard evidence that an empathy-linked behavior could be induced in canines.
But other experimenters weren't so sure about the results. A group at Hiram College in Ohio published a paper in 2009 directly contradicting the earlier results. They showed 17 dogs a video of a person yawning and only one of the dogs yawned.
That wasn't considered a knockout blow, though. A hopeful 2010 study attempted to test the hypothesis that contagious yawning in dogs in caused by empathy. The British researchers figured that if empathy is really driving contagious yawning, then the dogs would be more likely to respond to their owners' yawns because of their preexisting emotional connection. They took 19 dogs and had the owners and strangers yawn at them. Unfortunately, of the 38 trial runs, the dogs only yawned five times -- and all five were in response to strangers.
"Our results provide no support for empathy-based, emotionally connected yawning contagion in dogs and casts doubt on the recently documented phenomenon of cross-species contagious yawning," the researchers rather glumly concluded. "We interpret our findings as showing that if dogs are seen yawning contagiously then the contagion must be explained on less cognitively stringent grounds than empathy."
We still would like to believe that our animals empathize with us, perhaps because we empathize with them. (Who hasn't given her dog a birthday present?) But the balance of evidence right now seems to suggest that dogs don't yawn in response to our yawns. They might not be the empaths we want them to be.
On the other hand, just look at my dad's new dog's eyes! I'm pretty sure she's staring right into my soul.