Dogs can tell when you're happy, sad or frustrated

My dog usually lies calmly in the back of the car on trips. This morning she sat upright in the passenger seat, staring at me and bumping me with her cold nose. Pretty sure it was because she sensed my nerves at being on the way to a double root canal. But I hadn't noticed it. Now I have to look at my dog to find out how I'm feeling.

It’s a strange baseline when we need proof, and not the other way around.