THE ORIGINS OF THE DOG

The dog is part of a family of similar animals which includes not just dogs but also wolves, foxes, coyotes, jackals and wild hunting dogs. All these animals have points in common, the most important being their indispensable and highly adaptable teeth. Long before man met up with the dog on a domestic footing, its ancestors were undergoing the process of evolution.

Although the exact origins of the domestic dog remain uncertain, this evolution makes a fascinating study and helps us to appreciate the more deeply rooted aspects of anatomy and temperament. Man’s domestication of the dog has produced the incredible variety we see today. The five and a half million dogs kept as pets in Britain are a testimony to the continuing success of the relationship.

Where does the dog come from??
The dog belongs to a family of dog-like animals called Canidae which are pack hunters. The domestic dog is known as Canis familiais. Other members of the family are wolves, foxes, coyotes, jackals and wild hunting dogs. Some look like the dog, others are different. They all have the some thing in common – long, narrow heads with long jaws and plentiful teeth. The cheek teeth are adapted partly for slicing and partly for grinding and can effectively handle the both carnivorous and vegetarian diets.

The dental structure of the Canidea is one of the admirable qualities which has allowed them to spread so widely across the world and to survive in such a variety of habitats from arid desserts to the freezing Arctic, from tundra to jungle, and the mountain forests of Northern regions.

The evolution of the dog
Many different theories of the dog’s evolution have been developed and explored. The wolf, fox and jackal would have each been claimed as the dog’s direct ancestor. In the 19th century, the great diversity of the dog breeds led to the belief – championed by Darwin among others – that more than one wild ancestor had been involved. The jackal and wolf, and perhaps even the coyotes and hyena, were supposed to have been independently domesticated and their progeny later crossed, so mixing up the genetic possibilities of several distinct species. We now know this is inaccurate that the incredible varieties of today’s breeds of dog are the result of early dogs by man, plus the effects of genetic mutation.


Paleocene Epoch
Sixty million years ago, a small, weasel-like animal with a long, flexible body, long tail and short legs lived in the forests. This was Miacis, the earliest ancestor not only of canids but also of other families – those of raccoons, bears, weasels, civets, hyenas and cats. It walked, like a modern bear, on the soles of its feet (not like modern dogs which walk on their toes). These feet had five well separated digits. Miacis had the distinctive teeth of the carnivore. Its brain was small but significantly bigger than those of the other primitive carnivores living at the time, the creodonts. These, though far more plentiful than Miacis, did not play a part in the evolution of the dog and finally became extinct about 20 million years ago, though most died out long before that.

Oligocene Epoch
By the early Oligocene epoch, around 35 million years ago, Miacis had given rise to a variety early canids. Over 40 varieties of primitive canids are known to science, some being bear-like dogs, others hyena-like dogs, and others, the most curious of all, cat-like dogs. There were also dog-like dogs and these were ones destined to survive.

Miocene Epoch
By the early Miocene epoch, 20 million years ago, a very basic dog-like dog was in existence. Named Mesocyon, it had shorter jaws than the modern dog, a long body and tail and stubby legs. The hind foot was still five-toed and spread, unlike the compact four-toed foot of modern canids. By the late Miocene, 10 – 15 million years ago, we find fossils of Tomarctus, a canid with longer jaws and a bigger brain. While not having the degree of intelligence of the dog, it possessed all its social instincts.

Pliocene Epoch
The first true Canis made its appearance between five and seven million years ago. It was beginning to walk on four of its toes (the fifth was to become the dew claw) and had a more compact foot – ideal for chasing prey.

Quaternary Period
By the beginning of the Quaternary period, one million years ago, an early wolf, the Etruscan, was to be found roaming Eurasia. Recent studies suggest that the Etruscan wolf may well have been a direct ancestor of the domestic dog as well as of the present day wolves, including the small subspecies of the Middle East and India, Canis Lupus pallipes – an animal closer to the dog than any other wolf subspecies.
The old idea that dogs evolved from jackals, foxes or jackal/wolf crosses has been abandoned. Now most people believe the direct ancestor is likely to have been an animal similar to today’s grey wolf.

Early Domestication of the Dog
Recent fossil discoveries suggest that the first domestication of the dog took place in the Middle East at least 10,000 and perhaps as much as 35,000 years ago. Some scientists believe that the process of domestication began first with wolf scavenging in the middens of human habitation. Others think that the first contact between humans and wolves was when early man hunted the animals for food, killed the adults and took the puppies away for fattening up. Subsequently, wandering bands of Homo Sapiens brought the creature with them from the Middle East to Europe. Similar invasions may have occurred in Australia, with man importing an ancestor of dingo.

Civilian man has always represented his art and small sculptures of dogs with curled tails, dating from about 6500 B.C. have been discovered in Iraq. Domestic dog bones from an earlier period in the Stone Age (about 7500 B.C.) were excavated in the Yorkshire and similar finds have been reported from 10,000 year-old cave sediments in Czechoslovakia. The oldest domestic dog remains unearthed in the U.S.A. came from Jaguar Cave, a Stone Age Indian site in the state of Idaho, dated at around 8300 B.C. Evidence of two kinds of dog – medium and large – was discovered.

The domestic dog spread rapidly all over the world except for Antarctica. Wherever they have lived, dogs have thrived because of their moderate specialization, great adaptability, high intelligence and use of special co-operation – the power of the pack.

The Wild Cousins of the Dog
The modern relatives of the domestic dog are numerous. All are descended from the same early canid stock, but some are not true canid although they have dog-like features. These include the African wild hunting dog, the dhole, the bush dog and the raccoon dog.

Grey wolf
The Grey wolf occurs in North America, Europe, Asia and the Middle East, with up to 35 subspecies, including the Great Plains wolf that once followed the herds of American bison and the common wolf of European and Asian forests. It weighs 12-80 kg and its coat color ranges from white through grey to red-brown or black. In the wild it lives up to 16 yeas; in captivity up to 20. It feeds on a wide variety of prey including moose, deer, hares, beaver and domestic animals. The wolf will also take carrion and vegetation.

Red Wolf
The red wolf still occurs, hopefully, in South East America, but may well be extinct in the wild. It hybridized extensively with the coyote as the latter expanded eastwards. Weighting 15-30 kg, this animal is cinnamon or tawny-colored with dark grey or black streaks.

Coyote
This canid is found in Canada and North America and weights 11-15 kg. Its coat color is grey-buff with the black stripe down the middle of the back and black patches on the forelegs and tail. It feeds principally on rabbits and rodents but also takes antelope, deer and sheep. Occasionally, fruit and insects form part of its diet.

Jackal
There are four species of jackal, the golden from Africa, South East Europe and South Asia, the black-backed from East and South Africa, the simian from Ethiopia and the side-striped from Tropical Africa. The rarest is the simian, which perhaps only four to five hundred now exist.
Jackals are slim, dog-like canid weighing 7-15 kg, with coats that vary from yellow and gold, through russet with the brindle black and white back to grey with a white stripe on the sides. They enjoy a varied diet including fruit, invertebrates, insects, reptiles, small mammals and carrion.

Fox
There are four genera of foxes with 21 species. Foxes are one of the most widely distributed groups of mammal, being found in America, Europe and Asia and Africa. They live up to six years in the wild and up to 14 years in captivity. The four genera of foxes are: Vulpine foxes, South American foxes, Arctic foxes and Bat-eared fox.

Dholes
This is the Asian wild dog, distributed throughout the West Asia, China, India and Indonesia. A secretive animal weighing 12-20 kg with a russet brown coat and black tail, the dholes is under threat from habitat destruction and persecution by man. It feeds on insects, reptiles, rodents and deer, and often kills by disemboweling its prey. Dholes go hunting in packs and are extremely savage.

Bushdog
This is the least-known and most intriguing canid and comes from the forests of South America. It is a stocky, squat animal with wedge-shaped face, stubby ears and a short tail. The coat color is a rich brown. It weighs 5-7 kg. very little is known about the life and habits of this elusive species which is endangered at the present time.

Raccoon Dog
This animal is a native to Eastern Asia, the Far East, China, Japan and North Indochina, and has been introduced to the parts of Europe. It looks very much like the raccoon, but is not related to it. The raccoon dog weighs up to 8 kg and has a long, brindled black and brown coat with black face and legs and black striped tail. It consumes a wide diet including fruit, insects, invertebrates and occasionally small mammals.

African Wild Hunting Dog
This fascinating animal inhabits Africa where it is found from the Sahara down to South Africa. It occurs in a variety of habitats but prefers savannah land. It weighs 20-30 kg and has a dark coat with a pattern of light or yellowish blotches unique to each individual. It lives nine to ten years in the wild. Hunting in packs, this species will prey on anything from rodents to zebra and large antelopes.

Maned Wolf
This handsome South American canid weighs about 22 kg and has a red coat, black legs, muzzle and mane and white throat, inner surface of ears and tail tip. An endangered species, it is prone to disease, including kidney worms.

Dingo
This dog has inhabited Australia for at least eight thousand years. It also occurs in Malaysia, Thailand and Burma. It weighs around 20 kg and has a red/brown coat with white patches. It often attacks domestic animals such as sheep – a serious problem for farmers.