LEADER OF THE PACK

The wolf pack is very like a human family group, in which the oldest male and the oldest female are the leaders, and the young must do as they are told. Wolves and human have many patterns of social behaviour in common, for both evolved as social hunters who had to keep together in a team so they could kill animals larger than themselves. Wolves guard their territory closely and make their presence known by howling. Each member of the pack knows his or her position in the scale of dominance, and any wolf that tries to assert itself is likely to be expelled from the pack by the leaders. The only pair of wolves to mate are the dominant male and the dominant female, and after the cubs are born the father will bring meat back to the den for the mother. The cubs are suckled for about ten weeks, and then the mother and the younger wolves will feed them with regurgitated meat (partly digested meat returned to the mouth from the stomach) until they are old enough to start hunting with the pack. At first, the young cubs can behave as they like and all the wolves will put up with their play-fights, but as they grow older they too must learn to keep their place.

CUBS AND PUPPIES

The young of all members of the dog family (Canidae) look quite similar when they are new born. They are small, defenceless, blind, and shorthaired, with short legs and a little tail. At first, like all mammals, the cubs or puppies, which may vary in number from their mother. After a few days (about nine in the domestic dog) their eyes open, they begin to hear, and they soon need more solid food. This is provided by the mother, and in social species by other members of the group who vomit up (regurgitate) meat that they have previously eaten. A mother dog who looks as though she is being sick in front of her puppies is, therefore, not ill but is providing them with their first solid meal. In the wild the young are nearly always born in a den or hole in the ground, and in the same way a domestic dog need a dark, warm place where she can give birth, which will happen about 63 days after she has been mated.

BEHAVIOUR

ehaviour in the dog family is divided into two distinct groups of solitary hunters, and social hunters. The solitary hunters – that is, the foxes and South American wild dogs – live on their own, except when they are mating and rearing their young. The wolf, jackal, coyote, African hunting dog, dhole, and the domestic dog, are all social hunters. Their behaviour is in many like that of a human family in which the parents are the leaders, while the children should do as they are told until they are old enough to leave and form their own family groups. In a wolf pack, or a family of African hunting dogs, every individual knows which other dog is above or below it in the family hierarchy and it will fight hard to keep or to better its position. Even though wolves are such powerful killers, fights between them seldom end in death, and if one wolf is injured the others will often help it to feed.

SOLITARY HUNTERS
Foxes, including American grey fox, are solitary hunters that kill their prey by themselves. They do not, therefore, have the complicated, interactive behaviour of the social hunters. A fox’s tail cannot wag as expressively as a wolf’s and its upright ears are not so mobile. Even so, if a fox is frightened it will cower down to make itself look small, and if it is angry it will stand up as tall as can to look large and threatening.

SOCIAL HUNTERS
The African hunting dog and other social hunters not only have to provide enough meat for the family group but they must also defend themselves againts other large predators, like the big cats and hyena. However, human hunters have always been the main competitors of the social hunters. The wolf has been exterminated over much of its vast range in Europe and Asia, and the African hunting dog and the dhole are also near to extinction. Only the jackals and the coyote, being smaller and more adaptable, continue to flourish.

ON THE SCENT TRAIL

ll members of the canid or dog family have a far better sense of smell than any human, and they probably remember scents better than sights. That is to say, whereas humans remember how objects are placed in a room and what they look like, a dog will remember the arrangement of the objects by theor different scents. In all wild canids – wolves, wild dogs, jackals, and foxes – smell is the most highly developed of all the senses. The animal hunts with its nose, find its mate with its nose, and identifies every new being that comes into its territory with its nose. It can even tell whether other animals are relaxed or afraid by their smell. This acute perception of scent is made possible by the long nose of the skull which contains rolls of very thin bone ever which the particles of scent are drawn. With certain hunting and gun dogs, there has been selection for the sense of smell in preference to the other senses. These dogs, such as the bloodhound, can smell very well but are short-sighted.

SIGHT AND SOUND

Every domestic dog in the world, whether it is a Pekingese or a Great Dane, has inherited the eyes and ears of its ancestor, the wolf. All its senses have evolved for being a social hunter of large prey, but these senses have been adapted and developed in different breeds of dog by “artificial selection”. This means, for example, that in sight hounds, such as greyhounds, those puppies with particularly good sight have been chosen over the centuries as future breeders, so that in the course of time all greyhounds have developed even better sight than the wolf. One change that has been brought about in nearly all domestic dogs is that the eyes look forward rather than to the side, as in the wolf. Wolves and domestic dogs cannot hear as well as some other carnivores, because they usually hunt at dusk when sight is more important than hearing. Foxes, however, hunt at night and it is thought that their senses of hearing is more acute than a wolf’s.

DOG’S BONES

The skeletons of all mammals provide the solid framework on which the rest of the body is built. The bones of the skull protect the brain, mouth, eyes, nose, and ears. The backbone supprts the heart, lungs, and digestive system. The shoulder blade and hip girdle are the pivots which allow the limb bones to move. Attached to the ends of the bones, there are ligaments and tendons which act like strong elastic to keep them joined together yet moveable. Muscles are also attached to the bones in a complicated system that enables the body to move in all directions. Each bone in the skeleton has characteristics which make it recognizable as belonging to a member of the dog family. The skulls of wolves, dogs (both wild and domestic), and foxes are always long and the teeth large. The neck and the backbone are also relatively long, the ribs form a strong cage to protect the chest, and the long limb bones are adapted for fast running.

COATS, HEADS, AND TAILS

In the dog family, fur has many different lengths and textures. Fur is necessary to keep dogs warm, being denser in cold climates, but shorter in hot ones. It is composed of two layers: an undercoat of fine wool, usually of one colour, and a top coat of longer, coarser hairs, called guard hairs, which have natural oils to make the coat waterproof, and carry the stripy, or brindled,, pattern of the fur. Coat colours are variations of white, black, and tan. The heads of all wild dogs, whether large like the wolf, or small like the bat-eared fox, have long heads with erect ears, and teeth set in a line along straight jaws. Tails too are all similar, being long, straight, often bushy, with a white or black tip. A dog’s tail is one of its most important assets and is used for balancing when sunning fast, for expressing its feelings, and, when held up, as a signal to other members of its group. No wild dog has a tail permanently curled over its back. When dogs were domesticated, all these characteristics were altered by specially selecting certain features for each dog breed.

EVOLUTION OF THE DOG FAMILY

Thirty million years ago, during the Oligocene period, the first dog like creature, Cynodictis (amongoose - like animal with a long muzzle), appeared on Earth. It replaced the earlier widespread group of carnivores – the creodonts. All the earliest fossils of the dog family have been found in North America and date from this period. Another canid – like carnivore, Tomarctus , evolved during the Miocene period, from 24 million years ago. In turn the genus Canis evolved, which became Canis lupus , or wolf, some 300,000 years ago. From this wolf, the first domestic dogs date from around 12,000 years ago. There were also creatures that looked similar to these dog ancestors, such ad the hyaenodonts from the Oligocene, but they were not related to true hyenas, which are closer to the cat family. From ancestral carnivores like Cynodictis , the canids evolved into fast-running meat eaters that hunted prey on open grasslands, and most of today’s living species have inherited this way of life.

MODERN EVOLUTION

During the last Ice Age, from about 40,000 years ago, wolves and humans both lived as family groups of social hunters. They even competed for the same prey. They would have killed each other whenever possible, but it also likely that the wolves began to scavenge arround the debris left by humans. Sometimes young wolf cubs were tamed, and by breeding over many generations they evolved into domestic dogs.

WHAT IS A DOG ?

The Dog Family, called Canidae from the Latin canis meaning “dog”, includes around 37 species of living wolves, jackals, foxes, wild and domestic dogs. All member of the dog family, or canids, are carnivores, or meat eaters, and have special adaptations for hunting. Their teeth are used for killing prey, chewing meat, gnawing bones, and sometimes for fighting each other. Their highly developed senses of sight, sound, and smell with their large eyes, erect ears, and sensitive noses – mean they can track prey succesfully, whether they are social, or solitary, hunters. All wild dogs, except for the South American bush dog, have long legs adapted for running fast in pursuit of prey. All canids are “digitigrade” (they walk on their toes), and have distinctive feet, with five claws on the front foot and four on the hind. In domestic dogs, there is sometimes an extra, fifth claw (dew claw) on the hind foot. Wild dogs have long tails, and their dense fur is usually without spots or stripes. Canids usually mate once a year and, after two months’ development in the womb, produce a litter of pups. Like all mammals, the mother suckles her young after they are born and looks after them for several months, with help from the rest of the family.

WHAT IS NOT A DOG ?
Sometimes called dogs, the hyena, Tasmanian wolf, and prairie dog are in the dog family. The three species of hyena, within the Hyaenidae fanily, are more closely related to cats. The Tasmanian wolf, or thylacine, now extinct, was a marsupial (pouched mammal) that lived in Australia, while the North American prairie dog is a rodent related to squirrels.