What does Qiuqing mean by the zodiac?

Dogs are distributed all over the world. Dogs love to eat meat, but also eat dog food, human meals, fruits, snacks and so on. Dogs don't sweat They release heat by opening their mouths and sticking out their tongues. Dogs are seasonal monogamous animals, with estrus from March to May in spring, from 9- 165438+ 10 in autumn, and from 6- 10-2 in wild dogs, with estrus period of 6- 14 days. A dog's pregnancy is usually three months, and sometimes it can give birth to ten to twelve puppies at a time.

Some scientists believe that dogs were domesticated by early humans from gray wolves. The domestication time was 40,000 years ago-10.5 million years ago, and it has been developed to this day. As the pet with the highest feeding rate at present, it is called "the most loyal friend of mankind". It is witty, brave, faithful, reliable, considerate and versatile. Because of this, dogs are loved and protected almost all over the world.

morphological character

The lens of a dog is twice as thick as that of a human, and the adjustment ability of eyes is only 1/5~ 1/3 of that of a human. You can see clearly within 50m, but you can't see clearly beyond this distance, but the moving target can see 825m, with a wide field of vision. The left and right field of vision of one eye ranges from 100 to 65438. The lower field of vision is 30 ~ 60, and the object in front can be seen clearly. But because the dog's head is very flexible, it can basically "look at all directions with its eyes."

The dog can only see 25 degrees with one eye, so it can't see the nearest distance ahead. The lens of a dog's eyeball is relatively large and deformed like a horse's eyeball, so it is impossible to adjust the sense of distance. Twenty or thirty meters is probably its limit. Dogs have a special ability to detect moving objects; They can detect images that move 70 lines per second, while ordinary TV images move about 60 lines per second.