Yawn

Biology Letters published a study this week that found that when a human yawns, their dog will probably yawn too, a sign of empathy. What puzzles the people who did this study is that dogs lack a sense of self, something deemed necessary in understanding the feelings of others, which would cause contagious yawning. One of the authors of the study said "dogs are not only reading and responding but may be sharing feelings with humans."
I tried this with my dogs and Sparky and Gracie both yawned after I did. I had to yawn twice before they did though. Ginger and Rosie never yawned no matter how many times I tried.

Here is the abstract from the study:

"This study is the first to demonstrate that human yawns are possibly contagious to domestic dogs (Canis familiaris). Twenty-nine dogs observed a human yawning or making control mouth movements. Twenty-one dogs yawned when they observed a human yawning, but control mouth movements did not elicit yawning from any of them. The presence of contagious yawning in dogs suggests that this phenomenon is not specific to primate species and may indicate that dogs possess the capacity for a rudimentary form of empathy. Since yawning is known to modulate the levels of arousal, yawn contagion may help coordinate dog–human interaction and communication. Understanding the mechanism as well as the function of contagious yawning between humans and dogs requires more detailed investigation."