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1. Introduction: Dogs belong to the phylum Chordates, subphylum Vertebrates, Mammalia, Subclass Euzoa, Carnivores, Schizopoda, and Canids. Also known as "dog" in Chinese, dogs are found all over the world.
Dogs, horses, cows, sheep, pigs, and chickens are called the "six animals". Some scientists believe that dogs were domesticated from gray wolves by early humans, and were domesticated 40,000 years ago. Known as "man's most faithful friend", it is the pet with the highest breeding rate, and its lifespan is about 12-18 years.
In Chinese culture, the dog belongs to one of the 12 zodiac signs, the 11th place in the 12 zodiac signs.
2. Origin of species: Dogs were domesticated from wolves. As early as the hunter-gatherer era, dogs were domesticated as hunting assistants.
Therefore, dogs are considered to be the earliest domesticated domestic animals of humans. Dog bones have been found in Cishan in Wu'an, Hebei, Pei Ligang in Xinzheng, Henan, and Hemudu in Yuyao, Zhejiang, which proves that it has a long history of domestication. The dog-shaped stalk unearthed in Sanlihe, Jiaoxian County, Shandong Province has a vivid and realistic shape, allowing us to see the morphological characteristics of domestic dogs in the Neolithic Age.
The dog bones unearthed from the Banpo site in Xi'an, Shaanxi Province, have a small skull, a prominent frontal bone, a small flesh crack tooth, and a curved horizontal edge of the mandible, which is very different from the North China wolf, indicating that the history of human domestication of dogs is indeed very early.
3. Domestication process: The biological origin of dogs can be traced back to tens of millions of years ago, and the domestication history of dogs is about 15,000 years ago in the Mesolithic Age, and even some scientists argue from the perspective of genetics that dogs may have been domesticated by humans as early as 100,000 years ago. The first humans deciphered a dog's genome was in 2005 – even before researchers used genetic tools to trace the earliest homes of dogs.
Early studies have identified a high degree of genetic diversity in dogs in East Asia, and other key markers in many rural dog populations, leading them to point to East Asia as the earliest place where dogs were domesticated by humans.
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1. Dogs, a common canine mammal, are close relatives of wolves. It is called by some as "man's most loyal friend" and is also the pet with the highest breeding rate. Its lifespan is about 10 years, and if there are no accidents, the average lifespan is longer than that of small dogs.
A dog is a domestic animal that was domesticated by humans no later than 14,000 years ago, and possibly even 15,000 years ago. There are hundreds of varieties of domestic dogs, ranging from Chihuahuas with a height of only a dozen centimeters to Irish wolfhounds that are nearly a meter tall, and the colors range from white to black, gray or brown. Domestic dogs, like the human podace, are highly socialized group predators.
2. Dogs can't eat chocolate, coffee, and strong tea, which will damage their heart and central nervous system. Dogs cannot eat grapes and raisins, which can lead to kidney toxicity (kidney failure).
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Profile of the dog.
Brief introduction of the dog: Origin of the species Dogs were domesticated by wolves. As early as the hunter-gatherer era, dogs were domesticated as hunting assistants.
Therefore, dogs are the earliest domesticated domestic animals of humans. Dog bones have been unearthed at sites such as Cishan in Wu'an, Hebei, Pei Ligang in Xinzheng, Henan, and Hemudu in Yuyao, Zhejiang, which proves that its domestication history is long. Species lifespan The age of a dog is mainly judged by the following points:
1. The growth of teeth; 2. Tooth peak and tooth wear degree; 3. Appearance color. Under normal circumstances, the lifespan of dogs is between 10 and 15 years, and the average lifespan is about 20 years. The average lifespan is similar to that of cats, and the average lifespan is longer than that of small dogs.
Dog's sense of smell Dogs' sense of smell is the highest among all animals, and blind dogs can use their noses to live like normal dogs. The dog's sensitive sense of smell is mainly manifested in two aspects: one is the sensitivity to smell; The second is the ability to distinguish smells.
Sensitivity varies depending on the type of taste, and is about 1,200 times that of the human sense of smell. Dogs are tens of thousands of times more sensitive to smell acids than humans. Interpreting sleep Dogs are not easily woken up by acquaintances and owners when they sleep, but they are still sensitive to unfamiliar sounds.
After the dog is awakened from sleep, it often seems to be in a very bad mood, very dissatisfied with the person who woke it up, and the dog that has just been woken up is sleepy-eyed, and sometimes even the owner can not recognize it. So its frustration will sometimes vent to its owner, such as barking at you. Don't wake it up out of boredom or pranks.
Extended Information Species Contribution Service Dogs: Guarding Human Safety and Property, Caring for Homes and Homes... Playing with Dogs:
Accompany, play... Hunting Dogs: Hunting Charge....
Pastoral dogs: sheepdogs, cattle dogs. Medical Dogs:
Because dogs are optimistic by nature, they are suitable for taking care of and accompanying people with mental illness, depression, and autism (excluding violent patients); The premise is to choose a dog that has been domesticated and will not cause trouble, otherwise it may increase the burden and cause the disease to worsen. Nursing dogs: take care of people who have difficulty taking care of themselves and paralyzed people; It can help people take off their shoes and socks, insert cards to withdraw money, open and close doors, turn lights on and off, push carts, and take things from the refrigerator.
Guide dogs: Compared with the responsibility of the nursing dog, the responsibility is heavier, always accompany the owner, and most of the things the owner does need to be assisted by the guide dog; Guide the owner to cross the street, and the dog goes shopping alone.... Military Dogs:
Some countries have a special military dog medal; Military dogs, police dogs, customs drug detection dogs, airport gunpowder monitoring dogs... Search and rescue dogs: search and rescue work in the event of avalanches, **, fires and other disasters.
Traffic dogs: For example, Eskimos near the Arctic Circle and some people in Northeast China use "sled dogs". Show Dog:
Most circuses have dogs dedicated to performances, and they have a lot of skills and talents...
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