Dogs were domesticated from gray wolves about 15,000 years ago. Their value to early human settlements led to
them quickly becoming ubiquitous across world cultures. Dogs perform many roles for people, such as hunting, herding,
pulling loads, protection, assisting police and military, companionship, and, more recently, aiding handicapped individuals.
This impact on human society has given them the nickname "Man's Best Friend" in the Western world. In 2001, there were
estimated to be 400 million dogs in the world. ~wiki~
