Here’s a fun fact: The fundamental evolutionary split between dogs and wolves is that dogs will make eye contact with you, and wolves won’t. It’s a seemingly simple thing, but from that split came all the mutts we keep in our homes today. And it appears that, over time, dogs have learned to read human emotional states.
Researchers at the University of Veterinary Medicine, Vienna decided to test the supposed emotional intelligence of dogs by training them to paw at either a happy face or an angry one. The dogs only saw part of the face at any given time. Then the researchers swapped it out. Instead of showing the top half of a face, it showed the bottom, or showed parts of entirely new faces expressing the same emotions. Not only did the dogs pick the right face the majority of the time, it was easier to teach them to select the happy human.
The researchers speculate that part of the reason it worked so well is that the dogs knew, from experience, the difference between a face about to give them a treat and a face about to yell at them for knocking over the garbage again. Still, it shows they both have a comprehension of the different faces of humans and can react to them according to what they learn over time. So, yes, your dog knows when you’re a mess and just wants you to feel better, according to science. Cats, on the other hand, are best summed up with this GIF: