The Chow-Chow is a sturdily built dog, square in profile, with a broad skull and small, triangular, erect ears with rounded tips. The breed is known for a very dense double coat that is either smooth or rough. The nose should be black, but blue-coated Chow-Chow can have a solid blue or slate-colored nose. According to the American Kennel Club breed standards, any other tone is not acceptable for contests. FCI countries, however, do allow a self-colored nose in the cream.The blue-black/purple tongue gene appears to be dominant, as most mixed breed dogs that come from a Chow-Chow retain that tongue colour. To avoid aggression and over-protectiveness as an adult, continuous socialization as early as possible could allow the dog to adjust. When a Chow-Chow reaches adolescence it rejects authority from any owner who failed to earn its admiration. Aggression can be one distinctive behavioural characteristic in this breed, though while some are of an aggressive nature, many are known to be easy-going in nature – sometimes adopting an aloof disposition to individuals other than their owners.