If you want to know if your dog loves you, the answer may be in the way he wags his tail. It turns out that dogs who wag their tails are expressing an emotion usually more complex than just “happy”.

When dogs feel fundamentally positive about something or someone, their tails wag more to the right side of their rumps. When they have negative feelings, their tail wagging is biased to the left.

In humans, the muscles on the right side of the face tend to reflect happiness (left brain) whereas muscles on the left side of the face reflect unhappiness (right brain).

Dog tails are interesting, Dr. Davidson said, because they are in the midline of the dog’s body, neither left nor right. So do they show emotional asymmetry, or not?

The second half of the article goes into the left and right hemispheres of brains in other animals and how that may or may not help them in adapting to change and being aware of their surroundings. It’s a short but interesting read though.

I think I’m gonna go say ‘hi’ to Joey so I can see what he does.

Anyway, more photos of Joey here.