"Contagious yawning" is a phenomenon which is thought to relate to the capacity for empathy and has previously been reported in humans and chimpanzees. It is thought that such a contagiousness of yawning may help coordinate interactions and communication between man and his canine friends. Often contagious yawning is absent from humans who have autism.
In the experiment, published in the journal "Biology Letters", 29 dogs observed a human yawning or just making open mouth movements. 21 dogs yawned when they observed a human yawing, and no dogs yawned when they observed a human making open mouth movements. No yawns were observed during the interval between conditions either, and the number of yawns in the yawning condition did not differ significantly between sexes.
72% of dogs yawned in response to a human yawning, which is far higher than the number of humans or chimpanzees that yawn in response to a human yawning, suggesting that there were powerful selection pressures for dogs to develop empathy with their human owners during the process of domestication.
"Understanding the mechanism as well as the function of contagious yawning between humans and dogs requires more detailed investigation", said the authors of the paper.