The dog (Canis lupus familiaris) is the first domesticated animal to co-exist with humans. The first evidence of dogs already living with humans is over 30,000 years old. The dog is a subspecies of the wolf and belongs to the order of the predators. Research has shown that our dog is descended from four different primal breeds that have been domesticated simultaneously in different parts of the world.
Source: Tambako the Jaguar, Flickr (CC BY-ND-2.0)
Dogs and wolves
Genetically, there is hardly any difference between dogs and wolves. It is also clear that the dog is descended from the wolf; there is a genetic abnormality of only 0.02%. The genetic abnormality with, for example, the jackal or the coyote, which also fall under the wolf-like is 4%. Just as the differences between dog breeds can be very great, so is wolves. Certainly in prehistoric skeletons little difference can be seen between wolves and dogs and it is therefore not possible to say with certainty when the dog as a subspecies separated from the wolf. Over time, however, the behavior of wolves and dogs has changed. It is therefore no longer possible to compare the behavior of the wolf with that of the dog.
Prehistoric dog
The oldest dog found in the presence of a human settlement dates from 31,700 years ago and was found in the caves near Goyet, Belgium. Other older clues have been found, but it is not possible to say with certainty whether it was a dog or a wolf that happened to be near the settlement.
The domestication of the dog coincides with the transition from hunter / gatherer to farmer. The wild dogs and wolves near the first settlement likely began to live on human waste. While wolves can work together better and generally have a higher intelligence than dogs, the dog’s obedience may have been decisive in domestication.
Social life of the dog
The social nature of the dog makes the animal extremely suitable for living with humans. The dog is a pack animal and needs a leader who can satisfy his obedience. The more the dog can bond with an owner, the better he is able to cooperate. On the other hand, a dog can also easily get lonely in a socially poor environment.
Territory drift
The male dog (male) marks off the territory of his group by means of urine. The moment he smells that other dogs have entered his territory, he will refresh his beacons by urinating again. The beacons or flags are generally set at nose height, which is why males prefer poles and trees to urinate against. While this behavior is often seen as dirty, this territorial instinct is the basis of their being such good watchmen.
Reproduction in dogs
Dogs generally do not have a steady mate in breeding. Females are in heat for about one to three weeks once a year and after conception a gestation period of about 53 to 72 days follows. The number of puppies born in a litter varies by breed. The record is 22 puppies in one litter. Young dogs are born deaf and blind. Only after about 10 days their eyes open and a day or two later their hearing starts to work. They continue to nurse with the mother for about 6 weeks before switching to solid food.
Food for dogs
The dog is a carnivore by nature and its digestive system is identical to that of the wolf. However, most dogs also eat plant foods such as grass on a regular basis. This probably aims to clean the stomach.
With dog activity declining severely over the past centuries and increasing energy in food, obesity is a serious problem.
Dog senses
Dogs’ senses have often been praised. Hearing and sense of smell are particularly superior, although this can vary greatly from breed to breed. Their sense of smell must be very good, because scent is the primary form of communication in dogs. For example, they can learn a lot from both solid and liquid faeces with his nose.
A dog can perceive vibrational frequencies that are not audible to a human. Dogs’ ears can pick up ultrasounds with ease. The dog can also perceive a sound on average four times further than a human. The hearing is further refined so that a dog can distinguish the difference in tone of about one eighth tone. This allows him to recognize the sound of his boss’s car, for example.
Although the dog cannot distinguish color, it sees a lot sharper than the average human. Because his ancestors mainly hunted at dusk and in the dark, the dog can see much better in these conditions. The dog’s eyes can transmit more light and there is a high concentration of receptors (rods) in the dog’s eye, so that it can absorb much more light in contrast to, for example, the human eye. Recent research has shown that the dog can probably also see ultraviolet light.
- Class – Mammalia (mammals)
- Order – Carnivora (predators)
- Family – Canidae (dogs)
- Species – Canis Familiaris (dog)
