Do you get tired when others yawn? Does your dog get tired when you yawn? New research from Sweden establishes that dogs catch yawns from humans. But not if the dogs are too young. The study, published in Springer's journal Animal Cognition, found that, like humans, dogs show a developmental trend in susceptibility to contagious yawning. While dogs above seven months of age catch human yawns, younger dogs are immune to yawn contagion.