The brown rat, common rat, Norway rat, Norwegian rat or wharf rat (Rattus norvegicus) is one of the best-known and common rats, and also one of the largest. It is not known for certain why it is named Rattus norvegicus (Norwegian rat) as it did not originate in Norway, but John Berkenhout, the author of the 1769 book "Outlines of the Natural History of Great Britain", is most likely responsible for the misnomer. Berkenhout gave the brown rat the binomial name Rattus norvegicus believing that the rat had migrated to England from Norwegian ships in 1728, although no brown rat had entered Norway at that time, instead coming from Denmark. Thought to have originated in northern China, this rodent has now spread to all continents (except Antarctica) and is the dominant rat in Europe and much of North America. It lives wherever humans live, particularly in urban areas. Selective breeding of Rattus norvegicus has produced the laboratory rat, an important model organism in biological research, as well as pet rats.