Dogs are carnivorous mammals that have been experienced since the domestication of wolves 15,000 years ago or maybe have since 100,000 years ago based on genetic evidence and fossil discoveries of DNA tests. Other studies reveal the history of domesticated dogs that have not been so long.
The dog has developed into hundreds of races with different variations, ranging from the dog's height as several tens of centimeters Irish Wolfhound Chihuahua to a high of more than one meter. Dog coat color can be varied, ranging from white to black, also red, gray (often called "blue"), and chocolate. In addition, dogs have different types of fur, ranging from very short to the length can reach several centimeters. Dog hair can be straight or curly, and coarse-textured till soft as wool.
Intelligence
People like to get a dog because dogs are intelligent animals. Dogs are considered to have a high enough intelligence according to scientific research and field evidence. Dog intelligence level depending on race and each individual dog. Border Collie dog known to obey and carry out various commands. Another dog might not be interested to obey human orders, but rather show sophistication in other matters such as cattle herding.
The origins of the dog as the offspring of wolves that live in groups makes it easier dogs trained than other animals. As a member of the group, dog has the instinct to obey. Most of the dogs are often not need to deal with the complex task-complex, so there is no chance to learn things the hard way to open the door without human assistance. Dogs who are trained as guide dogs for the blind can recognize various kinds of danger and how to avoid these circumstances.
Sight
Dogs used to be thought the chromatic, so that could be called by the standard color-blind humans. But research conducted recently showed the dog can actually see some color, though not as you can see people. For dogs, the color is a subliminal signal that was captured to distinguish the shape of the object overlap, and not the color of objects that can be immediately distinguished dog. According to the study, the dog can see the various shades of yellow, purple or violet. Dog eye lens flatter than the human eye lens, so the dog can not see in detail than humans. Instead, the dog's eyes more sensitive to light and motion than the human eye. Some dog race, a field of view up to 270 °. In comparison, humans have only 180 ° field of view. Field of view of a dog race with a big head and two eyes in front of almost the same as actual human beings, only about 180 °.
Sense of hearing
Dogs can hear sounds up to 16 low-frequency 20Hz (humans only hear the frequency 20-70 Hz), and high-frequency sound from 70 kHz to 100 kHz (humans only hear the frequency of 13-20 kHz). In addition, dogs can move their ears in order to quickly determine the location of the actual sound source. More than 18 muscles in the dog's ear allows tilt, rotate, tuck, or enforce the earlobe. Dogs are able to determine the source of sound faster than humans, and could hear the sound source, four times more people who can be heard. Dogs with naturally shaped ears (ears up like a wolf) typically have better hearing than the dog's ear leaves are falling like the domestication of many species.
Sense of smell
Dogs have nearly 220 million smell-sensitive cells terhap smell. It was about as wide as a handkerchief, a very large when compared to cells of human olfactory owned. For comparison, humans only have 5 million olfactory cells which occupy wide wide stamps. Several types of dog were bred to be even deliberately puppies born with a sense of smell better. Information gathering mechanism in the brain based on the dog odor particles that successfully diendus clearly unknown. According to research, dogs can distinguish two types of smells: the smell in the air particles are spread from person or object, and the smell of the soil particles that can still be detected after some time. Characteristics of two types of particles seemed quite different smells. Odor particles in the air easily lost, but perhaps not so clear and smells mingled with others, while the smell of the soil particles are relatively more permanent. Dogs must be invited to do so repeatedly, and be careful, because the smell is easily embedded in the soil contaminated with odors other.
Bloodhound trainer has to understand that dogs are taught is no longer possible to track odors in the natural ability possessed since birth. Dogs can only be best motivated and taught to concentrate on the main scent trail. Trained sniffer dogs should be able to ignore the smell of other tracks. Untrained dogs are usually happy to sniff out various types of odor than the odor trail was ordered. While doing the grueling work for dogs (such as looking for contraband on the ship), the dog must be motivated to want to work hard in a long time.