A DOGS ORIGIN "MAN'S BEST FRIEND"

According to a work published in the journal "Science" in November 2002, a multinational group of scientists led by the prestigious researcher Peter Savolainen, from the Royal Institute of Technology (KTH), Stockholm - Sweden, studied the sequential analysis of mitochondrial DNA from the hair of more than 1000 dogs distributed around the world, reaching the unexpected conclusion that they shared the same genetic group. All domestic canines are descended from wolves that inhabited East Asia more than 15,000 years ago. It was concluded that Eurasian wolves are the closest ancestors of dogs. This incredible discovery suggests that dogs all over the planet descend from at least 5 female wolves, and their genes can be found in today's dogs.

Dr. Savolainen, who based his thesis on forensic and population genetic studies, especially in dogs and wolves, mentions that these results can still provide more information if the number of dogs is expanded in geographical regions of great importance. Furthermore, the origin and date of the first dog and the routes by which it spread from East Asia to the world can possibly be precisely established.

Prior to these revealing studies, the theory that dogs descended from wild canines was accepted: jackals, wolves, coyotes, foxes, hyenas,... but there was no thought of a common origin and their spread throughout the world accompanying man. Konrad Lorenz, ethologist and Nobel Prize in Medicine, maintained that the canine races descended from the Jackal and only some of the wolves. There is a remarkable resemblance between jackals and some breeds of dogs, but their behavior is vastly different. He maintained that the annoying jackals slept in the proximity of the bonfires, which the man of prehistory made, to rest and that they acted as sentinels with their howls when any other beast approached the camp. He mentions that the beginning of the affinity must have started with hunting and obtaining food.

However, this theory is ruled out and it is accepted that all dog breeds descend from Asian wolves and not from other wild canids. Wolves and dogs belong to the genus Canis of the large family Canidae. The first members of the Canidae family date back about 300 million years, and dogs arose from the evolution of the wolf, which is supposed to have started 20,000 to 30,000 years ago.

The great diversity of existing breeds, their different sizes and uses would be explained on the basis of a local wolf that, subjected to selective breeding by man, mainly in the last 500 years, evolved to create the different breeds. It was not due to different genetic origins, but to controlled breeding, exalting the sought-after characteristics and discarding the unwanted ones. The genetic change achieved in the evolution of the wolf to the dog is believed to have been linked to its domestication. During a long evolutionary process, man selected different natural faculties such as smell, sight, speed, temperament or speed to hunt, accentuating them in order to satisfy needs or whims. However, it is not known exactly how this transformation was carried out until it reached the domestic dog. Undoubtedly the speed with which they multiplied, adapted and differentiated indicates the important utility that the dog represented for man. According to these new revelations, domestication must have started in East Asia and not in the Middle East as previously thought. The subsequent migration of man from Asia to Europe was accompanied by the dog, facilitating colonization between 12,000 and 14,000 years ago, according to what could be established. The Spanish researcher Carlos Vilá, from the University of Uppsala in Sweden, mentions that the oldest fossil remains found date from about 14,000 years ago. He, however, considers that it is very likely that the dogs began to live with man many years before. In 1997, a paper was published in the journal "Science", indicating that genetic studies suggest that the origin of the dog could go back more than a hundred thousand years, although it is very likely that these animals were impossible to differentiate from wolves.

It is thought that the wolf was getting closer to the prehistoric man creating a beneficial society for both. They helped each other to hunt, track, monitor and protect until they consolidated a great affinity that thus allowed their domestication. However, this is just a theory that has not yet been proven. It is believed that the first approaches between the wolf and man in prehistory must have been made in relation to competition for food. Wolves and men depended on hunting for food and they did it in groups. Their social structures were similar and complex. It is accepted as a certain possibility that food waste left by man served as food to wolves considering their condition of eating carrion. Likewise, the great ability of the wolf to hunt and pursue its prey may have been the reason for the man to follow it. The found dog fossils, their presence in drawings and paintings, suggest that in ancient Egypt, as in Western Asia, the first dog breeds were developed and bred. It is known that in Roman times the dogs already resembled the current ones. It is also interesting to relate the discoveries of canine burials made in antiquity with respect to their domestication and their affinity with man. The oldest canine skeleton found from a burial was found in Central Russia about 17,000 years ago.

Paleontologists seeking to determine the origin of the dog have conducted geological studies based on fossils found in various parts of the world. To better understand the evolution in the dog family, one has to go back some 70 million years of geological history, to the Eocene period where the mammals that inhabited the earth were relatively new and their size was not very large. In that period there was a carnivorous mammal called Miacis. It was an arboreal animal that lived in Europe and Asia, with a long body and tail and relatively short limbs similar to a weasel. It had five fingers resting on the ground and retractable claws like cats.

In the Oligocene period, the Miacis evolved into another animal called Cynodictis that lived between sixty and forty million years in Europe and Asia. It kept its limbs short, its body and tail long, claws partially retractable with five fingers, and its hair was coarse showing very primitive characteristics. It was the first creature with anything like a dog.

Cynodictis gave rise to Cynodesmus during the Miocene period. The Cynodesmus was a strange cross between canine and feline modifying its skull, its limbs and its locomotion. He was a runner par excellence. He no longer supported himself with the five fingers, but the first finger remained rudimentary.

In the Pliocene period, Cynodesmus evolved into Tomarctus, which already had the shape of a dog, was also a good runner with longer limbs, also producing shortening of the first finger. During the Pleitocene, Tomarctus gave rise to the Canidae family and the Canis genus, from which arose the wolf (Canis Lupus), coyote, jackal, fox, feneco, wild dogs and Peat's dog. The wolf has been able to survive throughout the centuries, thus giving rise to the domestic dog (Canis Familiares). Dogs then evolved as a branch of Tomarctus.

The wolf has numerous habits and characteristics that are closely related to the dog, such as:

• They scratch and hide food under the ground.

• After urination and defecation, they scratch with their hind limbs to cover them.

• They both spin on their body.

• The duration of gestation in both is the same and varies between 58 and 65 days.

• The appearance of milk teeth and the change to permanent teeth are the same.

• They bark and howl the same.

• Both when attacking growl and show their teeth.

• They have the same number of chromosomes: 78, so they can mate with each other.

• They suffer from the same infectious diseases: Distemper – Hepatitis – Leptospirosis – Rabies – Parasitic.

• They fight twice a year.

For thousands and thousands of years the slow transformation from the wolf to the dog took place, which adapted like no other species to the needs of the human being. The long process of their domestication, the effective selection carried out by man and the breeding aimed at satisfying the most diverse needs led to the creation of the different canine breeds. It has adapted to the most diverse climates with extreme temperatures, rainfall, winds, and different geographies. It was used as meat, as a war dog, as a guard and protection dog, as a fighting dog, for traction, in hunting, as a tracker, as a shepherd to care for the flocks, as a racing dog, as a guide dog, in children with disabilities different, in the most diverse tasks of the security forces until becoming an essential company for man.

In 1984 the International Cynological Federation approved, at the proposal of Professor Raymond Triquet, the zootechnical definition for Group, Breed and Variety.

The “Breed” is “a group of individuals that present common characteristics that distinguish them from other representatives of their species and that are genetically transmissible”.

According to Triquet, "the Species comes from nature, while the Breed comes from culture, within the framework of cinophilia." The selection of the reproducers that will be crossed can lead to the birth of a new Race, but it never allows the creation of a new Species.

The Group is defined as a "set of breeds that have in common a certain number of distinctive transferable characteristics" All the individuals that belong to the same Group, despite having different morphologies, present the same original instinct. For example, members of Group 1 instinctively guard the herds.

The Variety is "a subdivision within a race, whose individuals also have a common transmissible character, which distinguishes them from the other individuals of the race." Within a Breed there may be different varieties of colors or textures and coats. For example, three varieties are allowed in Dachshunds: smooth hair, hard hair and long hair.

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