Fido really does know when you’re mad at him. A new study from researchers at the University of Lincoln in the UK finds that dogs can recognize the emotions of both other dogs and of humans, providing further evidence of the deep understanding that exists between pups and people.

For a study published in Biology Letters, researchers had 17 dogs look at pictures projected onto a screen of humans and dogs expressing positive and negative emotions (happy/playful or angry/aggressive). As they viewed the images, sounds of either a dog barking or a human voice speaking Portuguese (an unfamiliar language to these dogs) played in the background. The researchers tested whether the dogs spent more time looking at the faces when the faces matched the emotional tone of the sound playing (if the happy facial expression was paired with happy-sounding speech or vice versa). Whether the pictures were of humans or dogs, the dogs looked longer at faces expressing the same emotion as the sound. 

While people naturally think their pets can understand their feelings, rigorous scientific evidence for emotional recognition in animals is scarce, because dogs can’t tell you what they’re thinking. These results, the researchers argue, are evidence that dogs can recognize emotional expressions from both visual and audio cues, and can put the two together to figure out how others are feeling—the first evidence of a non-human animal being able to integrate and decode emotional cues in this way. Previous research has indicated that primates and perhaps even other social animals like sheep have some ability to decode emotions in the faces of their own kind, but this study adds more evidence to the hypothesis that pet dogs can also recognize the emotions of another species: Homo sapiens.

[h/t: The Conversation]