To reach this finding, scientists trained dogs to associate pictures of happy or angry faces with a reward. In a subsequent test, the scientists showed the dogs images of human faces they had not seen in their training. As National Geographic notes, over the course of the study, researchers repeatedly showed 20 dogs half pictures, either the lower mouth region or the upper eye area – of happy or angry human faces.
It was noted that half the dogs received a treat when they touched an angry face with their nose. The other half were rewarded for touching happy faces. In addition, 50 percent of the dogs learned the task sufficiently well to be tested, and there were then a number of different tests to find out if they could tell the difference solely on the basis of facial expression.According to the researchers, this behavior suggested that dogs could spot the difference between the expressions.
Commenting on the findings, lead researcher Professor Ludwig Huber, told the BBC that: “The main focus [of our research] is the big question of communication. How is it that dogs are so adapted to humans, and what’s happened during the process of domestication?”
The scientists are currently unsure if the dogs’ ability to discriminate between the two expressions is because of past experiences or the result of the domestication process.
The research was conducted at the aptly titled Messerli Research Institute’s Clever Dog Lab in Vienna. The research findings have been published in the journal Current Biology. The research paper is titled “Dogs Can Discriminate Emotional Expressions of Human Faces.”
