Dogs can recognise a happy or angry face, say experts. Photo / Thinkstock
Dogs can recognise a happy or angry face, say experts. Photo / Thinkstock
Everyone knows that dogs are a man's best friend - and now scientists have shown they can read our faces.
Researchers in Vienna have established that dogs are able to tell the difference between angry and happy human expressions.
They say this is the first credible evidence of any non-humananimal being able to recognise the countenance of another species.
"Our study demonstrates that dogs can distinguish angry and happy expressions in humans.
"They can tell that these two expressions have different meanings, and they can do this not only for people they know well, but even for faces they have never seen before," said Ludwig Huber, of the University of Veterinary Medicine Vienna.
"It appears likely to us that the dogs associate a smiling face with a positive meaning and an angry facial expression with a negative meaning."
The findings are based on tests in which two groups of dogs were shown a sequence of human photographs. One group was rewarded with food for touching pictures of people looking happy with their paws and the other for identifying those looking angry.
The food was dispensed automatically below the touchscreen every time the computer registered a correct response.
The dogs were able to select the angry or happy face more often than would be expected by random chance in every case, found the study, which also involved the Medical University of Vienna and the University of Vienna.
It is published in the journal Current Biology.
"Further work will be needed to figure out the behavioural and physiological consequences of observing emotions in others, for example, whether dogs show what we call 'emotional contagion' [the process of being emotionally affected by another's mood]," said co-author Corsin Muller, of the University of Veterinary Medicine Vienna.
