Recent studies conclude that dogs can see and hear the signs of human emotions, however, there weren’t anyone who said they could feel it too.
Until Biagio D’Aniello, a professor of zoology at the University of Naples in Italy, studied olfactory functions of dogs with his other colleagues.
“The role of the olfactory system has been largely underestimated, maybe because our own species is more focused on the visual system,” D’Aniello said.
D’Aniello and his colleagues organized an experiment and tested on whether dogs could smell human emotions by smell alone.
Volunteers watched videos that may cause fear, happiness, or a neutral response.
The team of researchers collected the humans sweat as samples. Those odor samples were then presented to domestic dogs, and the researchers monitored the dogs’ behaviors and heart rates.
Their findings showed that the dogs who smelled the odor of those who were scared showed signs of stress, compared to those exposed to happy or neutral smells. According to a report by NewScientist, the dogs exposed to fear odor had higher heart rates and sought reassurance from their owners immediately.
“We’ve always known that dogs collect information about their social partners through different sensory channels to decide how to respond to situations,” Marta Gacsi, of Eotvos Lorand University, told NewScientist. “However, it is not easy to investigate such processes so that we can unfold the mechanisms and separate the channels.”
On the other hand, Juliane Kaminski from the University of Portsmouth in the United Kingdom and her colleagues, studied how “dogs can return the favour, using their expressive faces.”
During the experiment, researchers introduced dogs to a human looking at them and some facing away, all the while presenting them food or not. The team analyzed how much facial movements dogs do in those different scenarios.
They found that a dogs’ facial expression varied the most when the human was looking at them and corrected the wrong connotation that dogs do not really try to look super-cute when they want something from their humans.