Dog DNA

 

                                                          Dog DNA

The most extensive study of ancient dog DNA to date has shown how rapidly dogs spread across the world after domestication and pins their likely origin to a group of extinct wolves.

Further info:

• By 11,000 years ago, dogs had already diverged into five different lineages and spread worldwide. It is widely accepted that dogs were domesticated at least 15,000 years ago. The new study suggests, but doesn’t prove, that domestication probably began around 20,000 years ago.

• Dogs probably evolved from an extinct form of wolf, yet to be identified. There is some disagreement among experts about the strength of this finding.

• Ancient dogs were much more diverse genetically than modern dogs. Four thousand years ago, European dogs had a wide genetic diversity that disappeared long before the Victorians started creating new breeds. All European dogs appear to have descended from one group of ancient European dogs, and the great modern diversity of dog shapes and sizes indicates an emphasis by breeders on certain very powerful genes.

• Dogs are a continuation of a line of wolves, but since those wolves became dogs more than 15,000 years ago, no new wolf DNA has entered dog genomes. This puzzles researchers because humans crossbred dogs and wolves, but none of the wolf DNA survived in dogs at large. Modern wolves, however, do show the incorporation of some dog DNA.

• The geographic spread of dogs sometimes mirrors and sometimes diverges from human migration, leaving unanswered the effects of dog-trading and why the genes of particular populations of dogs sometimes extended and other times did not.