It is widely known and accepted that dogs wag their tails when they’re happy and excited. This isn’t exactly true. Studies have shown that a way a dogs wag their tails gives us clues to how they’re feeling.
Tail wagging to the right indicates positive emotions. Wagging to the left is an indicator of negative emotions. This has to do with how the brain’s left hemisphere controls the right side of the body and vice versa. Studies have shown that the left hemisphere is associated with positive approach feelings and the opposite on the right hemisphere. Additional studies have shown that other dogs are able to tell how your dog is feeling by seeing how your dog wags its tail!