Ripe plums hit animals in cloudy weather.

The ripe plum weather attacked an animal: a dog.

Dogs belong to Chordata, Vertebrate, Mammalia, Orthoptera, Carnivora, Schipoda and Canidae. Chinese is also called "dog", and dogs are distributed all over the world. Dogs, horses, cows, sheep, pigs and chickens are also called the traditional "six animals". Some scientists believe that dogs were domesticated by early humans from the gray wolf, and the domestication time was from 40,000 years ago to 1.5 million years ago.

Known as "the most loyal friend of mankind", it is the pet with the highest reproductive rate, and its life span is about 12~ 18 years. In China culture, dogs belong to one of the 12 Zodiacs, ranking 1 1 among the 12 Zodiacs.

origin of species

Dogs are domesticated by wolves. As early as the era of hunting and gathering, people have domesticated dogs as hunting assistants. So dogs are the earliest domesticated domestic animals. Dog bones have been found in Cishan, Wu 'an, Hebei, Peiligang, Xinzheng, Henan and Hemudu, Yuyao, Zhejiang, which proves that it has a long history of domestication. ?

The dog-shaped scorpion unearthed from Sanlihe River in Jiaoxian County, Shandong Province is vivid and lifelike, which makes us see the morphological characteristics of domestic dogs in Neolithic Age. The dog bones unearthed from Anbanpo site in Xi 'an, Shaanxi, have smaller skulls, protruding frontal bones, smaller teeth and curved horizontal edge of mandible, which is quite different from that of North China wolves, indicating that the history of human domestication of dogs is indeed very early.