Answer:
Like a few of the ancient breeds (including their relatives, Chow Chows), Shar-peis have black mouths. As with Chow Chows, it was believed in ancient times that the dark mouth, exposed when barking, helped to ward off evil spirits.
First answer by Justin Andrews. Last edit by Justin Andrews. Contributor trust: 1 [recommend contributor recommended]. Question popularity: 2 [recommend question].