New research shows that all dog breeds come from the gray wolf

Dogs and humans have been living together for at least 15 000 years.

Dogs were domesticated thousands of years ago as companions to humans and bred for different traits. The desired traits changed over the centuries resulting in different breeds.

As humans migrated to different places on the planet over the millennia, their dogs went with them.

A team of researchers has assembled the most comprehensive genomic map on dogs to date. The results were published in the journal Cell Reports.

Researchers gathered blood samples or mouth scrapings from 1,346 dogs, of 161 breeds, over the course of 20 years. The dogs came from Europe, North America, Africa, and Asia.

Dogs were bred into 23 types or clades

For example, herding dogs, such as shepherds, collies and shelties, cluster into one clade, whereas hunting dogs, such as retrievers and setters, cluster into another clade.

This clustering indicates that dogs were originally bred for specific purposes before breeders began selecting for specific physical traits that are commonly associated with distinct breeds today.

It seems that people started breeding dogs for particular traits in multiple places at once. For instance, with the advent of agriculture, humans in multiple places in the world employed dogs for herding and guarding livestock.

When dog fighting was a popular form of entertainment, many combinations of terriers and mastiff or bully-type breeds were crossed to create dogs that would excel in the fighting ring. In this analysis, all of the bull and terrier crosses go back to the terriers of Ireland 1860–1870.

Later on, dogs were bred for more specific tasks. Golden Retrievers, Irish Setters, and other “gun dogs”, can be traced to Victorian England where these breeds were bred as retrievers, helpers and companions to hunters.