While every dog owner knows that their pooch can discern their moods perfectly, scientists have always been a little skeptical. Now thanks to some researchers at the University of Veterinary Medicine in Vienna, Austria, we finally have some tangible evidence.

For their study, biologist Corsin Müller and his team selected eleven dogs, including nine Border Collies, a Fox Terrier, and a Sheltie. They began by exposing the dogs to digital images of women that were either angry or happy. Half the dogs were rewarded for touching the screen when shown a happy face, while the other half got their treat for selecting those that appeared angry.

What was interesting was the pooches were not provided with the entire face. Some dogs were shown only upper halves while others observed lower halves. That's because the scientists who published their findings in the journal Current Biology on February 12th, believe that humans show their emotions on their entire face. Hence by exposing them to just partial expressions the researchers were teaching the dogs to recognize small nuances like the wrinkle between the eyes or the changes in their shape that accompany the happy or angry expressions.

While the dogs were able to grasp both emotions, the researchers found that those being trained to read angry expressions took longer to learn. They speculate it may be because dogs find angry faces aversive, causing them to retreat quickly. However, once the smart pooches realized they were getting rewarded the trepidation seemed to vanish. In fact, the dogs had such a good time playing the computer 'game' that scientists had a hard time keeping them away from the touchscreens after the study was completed.

Once the dogs were trained, the researchers tested the animals in different ways. This included exposing them to (a) the same half of the faces as in the training, except the faces belonged to new people, (b) the other side of the faces they had seen in training (c) the other half of the new faces and (d) the left half of faces used in training. This last trial was based on previous studies that have shown that canines have a preference for the left side of the human face.

For the most part, the dogs were able to identify the correct expression. This demonstrated that they are not only capable of recognizing familiar facial expressions, but also transferring their knowledge to people they have never seen before. Given that the only thing that was distinguishing the photographs was the expressions, the scientists felt comfortable in concluding the dogs were smart enough to read human emotions.

The researchers also noticed that only dog with a male owner had a harder time understanding the expressions correctly. Since the touchscreen models were all females, this confirmed what has been observed in previous dog studies - canines are more efficient at discerning facial expressions of people that are the same gender as their owner.

Given the close bond between dogs and their owners, most researchers are not surprised at the findings of the study. The one thing they are not sure of is how this expression discerning ability is affected if the dog does not have close human contact. And in case you are wondering, the team does plan on conducting similar studies on cats and even pigs and hand-raised wolves. So stay tuned to see if your beloved pet is as smart as dogs are!

Resources: natgeo.com, sciencedirect.com, wired.com