Read More: New Scientist
Dog owners swear that their furry best friend is in tune with their emotions. Now it seems this feeling of interspecies connection is real: dogs can smell your emotional state, and adopt your emotions as their own. Science had already shown that dogs can see and hear the signs of human emotions, says Biagio D’Aniello of the University of Naples “Federico II”, Italy. But nobody had studied whether dogs could pick up on olfactory cues from humans. “The role of the olfactory system has been largely underestimated, maybe because our own species is more focused on the visual system,” says D’Aniello. However, dogs’ sense of smell is far superior to ours. D’Aniello and his colleagues tested whether dogs could sniff out human emotions by smell alone. First, human volunteers watched videos designed to cause fear or happiness, or a neutral response, and the team collected samples of their sweat. Next, the researchers presented these odour samples to domestic dogs, and monitored the dogs’ behaviours and heart rates. Dogs exposed to fear smells showed more signs of stress than those exposed to happy or neutral smells. They also had higher heart rates, and sought more reassurance from their owners and made less social contact with strangers.