Among us, surely everyone knows that a dog is a lovely and very useful animal for humans. Many people see them as guardians of the house, some even see dogs as a loyal friend. But do we know dogs well enough? Let's learn about this adorable animal!

Dogs were the first domesticated animals to be domesticated by humans 12,000 years ago in the Stone Age. The ancestors of dogs include foxes and wolves, while the dog as we see it today evolved from a little gray dog.

Dogs are four-legged, omnivorous animals. The average size of the dog is 40-160 cm long. Dog eyes have up to 3 eyelids: One upper eyelid, one lower eyelid and the third eyelid is located in the middle, slightly inward, helping to protect the eyes from dust and dirt. Their ears are very sensitive, able to pick up 35,000 vibrations in just one second. Their sense of smell is as good as their ears. One can smell food somewhere in the kitchen, but dogs can distinguish every spice in the pot, and even hunting dogs can find small mushrooms deep in the woods, because they can distinguish nearly 220 million odors. Fingered limb: 5 toes in front, 4 toes in back. The toes have claws but do not retract, so they do not climb and are difficult to hold their prey for long. Dogs run far and are soft thanks to their long legs. The dog's brain is very developed. Dogs distinguish objects first by motion, then by light, and finally by shape. Therefore, their vision is very poor, only seeing 2 colors black and white. We have seen that in the cold winter, sometimes dogs or tails cover their wet noses, that's how they keep themselves warm. Various fur colors. Dogs have up to 2 layers of fur: The outer layer as we have seen, and the inner lining to help them keep warm and dry on rainy days, and even have the task of "cooling down" on hot days. .

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