The Origin of Dog Animal Canidae

Canids are mammals with characteristic canine  teeth and a skeleton built for walking. They belong to a predator group developed during the early Tertiary Period (65 million years ago) in the ecological areas abandoned by the large reptiles when they disappeared at the end of the Mesozoic Era  (65 million years ago).

The modern canid family consists of three subgroups:

Cuoninae (Lyacon), Otocyoninae (South African Otocyon) and the family Canis (dog, wolf, fox, jackal, coyote).

Canis / Caniderna crossed the Bering Strait and reached Europe during the late Eocene Epoch (35 million years ago). In late Miocene Epoch (10 million years ago) Canis emigrated to Europe from North America. These resembled the modern dog, but was more like a prairie dog to size. During Pliocene Epoch (5 million years ago) these  canids were spread to Asia and later also to Africa. Strangely, they were not to be found in South America until much later, during the early Pleistocen Epoch (about 2 million years ago).

Finally, man introduced the genus to Australia for some 500 000 years ago, during the late Pleistocene. There is no evidence that Australia's early canids gave origin to the dingo, contemporary wild dogs who came to Australia for only 15000-20000 years ago.

Canis etruscus existed for about one to two million years ago. Although they are smaller in size, it is believed that they are the ancestors of European wolves. Canis cypio, which occurred in the Pyrenees for about eight million years ago, considered to be the ancestor to modern jackal and coyotes.

A number of dog variants have been found at archaeological sites in Europe. The largest is believed to have descended from the great Scandinavian wolf who had the same height of our time Great Dane. They probably gave origin to the Nordic dogs and large dogs herding. Smaller dogs, are the same as contemporary wild dingo, probably derived from smaller wolves from India or the Middle East.

Descendes dog from the wolf?

The oldest dog skeleton ever found is about 30,000 years old, and it strains from the period after the Cromagnon. The remains have always been found near the human skeleton, which gave them the name Canis familiaris. It seems logical that domesticated dogs comes from early wild canids. Other possible ancestors include wolf, the jackal, and the coyote.

The oldest remains of dog have been found in China, where it is believed that the jackal and prairie dogs never lived. It was also in China  the first certified union between man and wolf, a smaller variety took place (150,000 years old). Coexistence between these two species over a period of their development underlines the theory that the wolf is the ancestor of the domestic dog.

This has been reinforced by a number of discoveries such as the Nordic breeds directly derived from the wolf. DNA has shown that there is a similarity that is greater than 99.8% between dog and wolf, compared to 96% between the dog and the coyote.

More than 45 speices are classified for the wolf, this diversity may partly explain the many breeds of dogs. Finally, body language and vocal languages in both species resemble each other very much and is widely understood between them.
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To tame the wolf

Wolves were domesticated when man went from hunter to growers. Some individuals may have been domesticated in early trials. When the domesticated wolf died, began the process of taming a new one. This was an important first step towards domestication of an animal species. The next step involved controlled breeding.

Probably began domesication of the wolf in various places in Asia.

Attempts were made around the world with young puppies from different groups. The puppies were marked on the man during their first months of life. It had succeeded when they rejected their wild relatives. The wolf puppies naturally lived under a flock of rules, the ranking did domestication easier. Sometimes it happened that domestic females were fertilized by wild wolves. Despite that the puppies stayed close to the people, and rarely returned to the wild flocks.

From wolf to dog

The wolf domestication led to a number of morphological changes and behavioral change, this was in line with human development. By studying the skeletal remains it have been found that there was a youthful regression, where the adult animal is kept some immature characteristics and behavior through the generations, as well as reduced size, cut nose, depth stop, wow, squeak, playfulness.

This has led some researchers to believe that the dog is still undergoing artforming, that it is stuck in his youth role, and are totally dependent on humans for survival.

Paradoxically the phenomenon means a shorter period of growth, which means that the puppies reach puberty earlier, and therefore can reproduce earlier. This explains why small breeds often reach puberty earlier than large breeds, and that all domestic dogs reach puberty earlier than wolves, which are not sexually mature until they are about two years old.

Results of selective breeding

Different breeds are only variations, types of Canis familiaris. Apart from a few number of breeds, whose blood line was maintained in a limited area, is the most dog breeds produced by selective breeding carried out by people. This could only occur after domestication, and by controlled breeding. The various dog species have adapted very fast in terms of climate, civilizations and geographical areas if compared with non-domesticated species, ex crocodile.

We know that the dog derived from the wolf. Does that mean that if we let the dogs be wild, they would become wolfs again?