Domestic dog, carnivorous mammal, generally considered the first domesticated animal. The domesticated dog has coexisted with human beings as a working partner and household pet in all eras and cultures since the days of the cave dwellers. It is generally believed that the direct ancestor of the domestic dog is the wolf, originally found throughout Europe, Asia, and North America.
Remains of a dog, estimated to be 10,500 years old, have been found in Idaho.
TAXONOMY Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Carnivora
Family: Canidae Genus: Canis Species: Canis familiaris
ECOLOGY & HABITAT
Little is known about wild dogs of the past but that they are carnivores: hunters and scavengers. This means that they are secondary consumers in web chains. Eventhough they are carnivores they sometimes accept eating green plants.
The ecology of dogs right know is that it helps the human in many fields of life.
Since the cave dweller times, dogs have been domesticated by humans and it has helped him to hunt, in herding, protection, etc. It has been very important as a work animal and as a psychological support for humans. The habitat of the dog is where it’s owner lives. Different dogs have different adaptations to their ancestral habitat but nowadays, this is not applicable.
The skeleton of the dog is the articulated structure, moved by the muscles, that holds the dog’s body and protects some organs and the nervous system. It also functions as mineral and blood deposit of the body. The skeleton of a dog is made up of approximately 321 bones: 134 form the axial skeleton (skull, vertebrae, ribs, etc.), and 186 form the appendicular skeleton (appendages). An extra bone has to be added for male dogs which is the penile bone. The dog is a digigraded animal (it walks with it’s toes). It lies on it’s third phalanges which are protected by palm cushions. The dog’s toes are arranged in an angle which gives more facility of rest after running or other activities. The teeth of the dog is composed of 42 teeth which include canines, molars, incisors, etc.
Joints permit the movement of the bones. There are three types of joints in a dog: fixed joints, movable joints, and semi-movable joints. Fixed joints, such as the ones in the skull don’t permit any movement but keep the bones together.
The semi-movable joints are those t...
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...e responds with the same howl. Two dogs that may encounter an bark are just imposing themselves. This makes them have more confidence. The nature of dog sounds can be described as follows: a hoarse and cut bark expresses a menace (a dare to another animal or an advice to an intruder so that it moves out of the territory), a happy bark ( coming to its owner or before going for a walk), a special bark to indicate a prey, etc. Then there are the obvious sounds: cry, lament, howl, screams, and grunts.
The look of a dog can tell a lot. A fixed look means fear or malevolence. The look of a dog to sheep or cows can control them and place them in order.
ATTITUDES AND MIMIC
Gestures of a dog to show happiness are the constant movement of the tail. A tail between the legs means fear. A dog in an aggressive posture shapes and moves its body to make it look bigger: it elongates, it’s hair gets straight up, etc. To exhibit submission a dog often lies itself on the floor and with its tail between its legs it shows its genitals. When a dog tries to play with another it lies in a sphinx position, or it "dances" around the other dog, or it gently bites the other’s tail, etc.