Origin of the domestic dog to the domestic dog and modern wolf lineages. The gray wolf is thought to be ancestral to the domestic dog, however its relationship to "C. variabilis", and the genetic contribution of "C. variabilis" to the dog, is the subject of debate. The Zhokhov Island (8,700 YBP) and Aachim (1,700 YBP) canid haplotypes fell within the domestic dog clade, cluster with S805, and also share their haplotypes with – or are one mutation away from – the Tibetan wolf ("C. l. chanco") and the recently-extinct Japanese wolf ("C. l. hodophilax"). This may indicate that these canids retained the genetic signature of
Dog type were described as species by Johann Friedrich Gmelin in 1788, and by Robert Kerr in his English translation of "Systema naturae" ("The Animal Kingdom") in 1792. Today the species Linnaeus named are identifiable as dog types, not species or subspecies. Some, such as "Canis aegyptius", a hairless dog type of Peru, have been documented and registered as breeds (Peruvian Hairless Dog). There are only two categories (subspecies) of domestic dog, "Canis lupus familiaris" and "C. l. dingo", recognized by the International Code of Zoological Nomenclature (ICZN Code). Beginning with the advent of dog shows in the mid-19th century in England,