Dogs are not universally accepted as man's best friend for simply being friendly, as a new study confirms the animal typically taken as a pet can read its master's mood.

According to Live Science, authors of a study published in the journal Current Biology showed 11 different dogs pictures of human faces appearing happy or angry. However, they were only shown the upper or lower half of the face at first.

To prevent the dogs from recognizing the person in the picture, the researchers showed the animals a different half of a different face or a different half of the same face. In some cases, the dogs were shown the same half of the same face to see if their reaction was consistent.

"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," study author Corsin Müller, of the University of Veterinary Medicine Vienna, said in a press release.

The researchers concluded that it would be too farfetched to suggest the dogs were picking correctly at random.

"We can rule out that the dogs simply discriminated [between] the pictures based on a simple salient cue, such as the visibility of teeth," Müller told Live Science. "Instead, our results suggest that the successful dogs realized that a smiling mouth means the same thing as smiling eyes.

"With our study, which was inspired by these previous attempts, we think we can now confidently conclude that at least some dogs can discriminate human facial expressions."

In addition to being a widely popular family pet, dogs are often used as therapy animals intended to ease stress or help an individual cope with loss. Müller said the study is further evidence of "the extraordinary bond between humans and one of their favorite pets."