Approximately 15,000 years ago the first domesticated dogs arrived.  They originated from their bigger ancestors the grey wolf.  It is not certain how they developed, but man used wolves as working animals for hunting, stock control, and to defend against attack.  As a result, the wolf was domesticated gradually and slowly the wolf became tame enough to be used as a working animal.

At this time, the dog would have looked like a fairly uniform creature, a semi wolf-like animal with strong bones and a big skull. However, selective breeding took place, and the wolf gradually evolved from a creature that could not be trusted to a creature that was required to function in various roles: defence, herding, hunting and tracking.   Thus evolved the reliable, trustworthy companion we see today.   

In the 17th Century, owning  a dog became a status symbol, from the working ‘beasts’ of prior, they were now smaller, tamer, and more attractive than ever before.  As a result of the status they had gained as pets, people started to breed dogs selectively for individual desirable features, such as colour, size, nature, temperament and ability.  Over time the dog slowly became smaller than the gray wolf, although the breeds are directly linked and share a very similar bloodline, they are different.  Even though the dog has evolved, it is still a social pack hunter.  Feral dogs are known to hunt in packs and develop a class system similar to wolves.