In Europe when dogs first made their appearance it seems they had oriental origins. When analyzing the remains of dogs, the most common was very similar to the actual fox and this explains that even today, between the most ancient breeds such as the Pomeranian, there are similarities.
Canine breeds have presented the most outstanding polymorphism without having divided into subspecies: there aren’t any other animal species that have all the different varieties in shape and form like dogs do, ranging from height, weight, shapes, colors, coat texture, body structures and skeletal and skull shapes.
It is reported that there are about four hundred breeds, ranging from the Saint Bernard down to the Chihuahua. These diverse characteristics are attributed to causality, natural selection, as well as the selection that man made and make that best adapt to his or her lifestyle.
Aptitudes and human selection of dogs: We can observe in prehistoric paintings, scenes in which hunting is done with a pack of dogs chasing their prey next to men with spears. With the advancement of civilization, dogs became war companions. There are many famous scenes of hunting and war where ferocious dogs combat next to men. Greek authors have narrated combats of heroic dogs that combated in war and defended cities from their enemies. Everyone has heard about the story of the profound relationship of loyalty and devotion between the dog Argos and Ulysses. It has also been shown that people used to cut the tail and ears of their herding dogs so that the ferocious beasts they fought against stood less of a chance of bringing them down. Even at those times dogs were being trained to “go to war” and for a long time in the Orient people used to celebrate dogfights; in ancient Rome fighting dogs did the same with gladiators and combated with them in the circus. Men tried to assure the animals that most responded to their particular needs, meaning that if a dog had a particular and extraordinary talent, they then would hope that the litter came with the same attributes. In a sense this is when the breeds that we now know today were being born and raised.