Ammon News - AMMONNEWS - Many dog owners believe their canine friends can tell when they are happy or sad - and now science has presented - for the first time - evidence that could help explain that emotional bond.

The new study recently published in the academic journal Current Biology has found that dogs react in the same manner a human brain reacts when exposed to non-verbal communication.

"Our study demonstrates that dogs can distinguish angry and happy expressions in humans," Discovery News quoted lead author Ludwig Huber saying. He explained that “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."

The team of animal behavior specialists from the University of the Veterinary Medicine in Vienna trained 20 dogs - of different breeds - to respond to the visible emotions on photographs of either whole faces or just the eyes or mouth.

The dogs were split into two groups – with half trained to recognize happy faces, the other group, angry ones.

When the dogs touched the correct screen corresponding to the emotion they were trained to recognize, they were rewarded with a food treat.

The scientists found the dogs trained to respond to happy faces were more capable of identifying the same emotion when presented with an unfamiliar face, but those trained to respond to angry faces reacted at a slower pace.

“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,” Ludwig said.

“We think the dogs in our study could have solved the task only by applying their knowledge of emotional expressions in humans to the unfamiliar pictures we presented to them,” Co-author Corsin Muller said, according to the Daily Mail.