A new research study published in the Proceedings of the National Academy of Sciences on May 21, 2012, reports that the long and varied history of dogs and humans has resulted in a major disconnect between ancient dogs and modern breeds.
One of the few modern breeds of dogs to retain a tiny trace of its genetic origins, the Finnish Spitz was rescued from extinction by a single determined breeder. Photo of Ginger by NoŽl Zia Lee
Dogs were domesticated from the gray wolf at least 15,000 years ago, although where that happened and whether it happened once or several times is still a controversy. Since domestication occurred while humans were all hunter-gatherers at the time and thus led extensively migrant lifeways, dogs spread with them, and thus these dog populations developed in geographic isolation for a time. Eventually, however, human population growth and trade networks meant people reconnected, and that, say scholars, led to admixture in the dog population. When dog breeds began to be developed about 500 years ago, they were created out of a fairly homogenous gene pool, from dogs with mixed genetic heritages which had been developed in widely disparate locations.
Since the creation of kennel clubs, breeding has been selective: but even that was disrupted by World Wars I and II, when breed populations all over the world were decimated or went extinct: dog breeders have reestablished such breeds using a handful of individuals or combining similar breeds.
Larson G, Karlsson E, Perri A, Webster MT, Ho SYW, Peters J, Stahl PW, Piper PJ, Lingaas F, Fredholm M et al. 2012. New genetic, archeological, and biogeographic perspective on dog domestication. Proceedings of the National Academy of Sciences Early edition.