What are the signs of animals before it rains?

Length pig. "There is grass in the pig's mouth, and the cold wave is coming." "Pigs build nests and it snows heavily." This is because the pig's nose and mouth are hairless, and it is in direct contact with the air. It is particularly sensitive to cold. Before the cold wave came, it had foresight and hurriedly took grass as its nest. If it's a little cold, stick your mouth in the grass. If it is colder, you will get into the grass to keep out the cold, and the sow will be more sensitive. Therefore, seeing the grass on the pig street is a sign that the cold wave is coming. 2. dogs. The dog is soaked in water, and it's going to rain. Because dogs don't have sweat glands, they can't rely on pores to dissipate heat in summer, so they can only keep constant temperature by opening their mouths and pulling their tongues to dissipate heat. When your mouth and tongue are useless, jump into a pond or stream to soak in water to help dissipate heat. So finding a "dog in the water" indicates that it is going to rain. When it is cold, the dog crouches on the haystack and uses his mouth as a "heater" to warm his navel, which indicates that a cold wave is coming. 3. Toad. Toad is also an expert in prediction. Its physiological structure is special, its lungs are like football, and its breathing power is not great. It is impossible to get enough oxygen only by breathing with such lungs. So toad has to rely on his skin to help him breathe besides his lungs. One condition of breathing through the skin is to keep the skin moist, so that the oxygen in the air can be dissolved in the mucus of the skin first, and then enter the blood from the skin. If the skin is dry, you can't breathe and it's hard to live. So it is very afraid of strong light and dry weather, hiding in the dark during the day and coming out for food at night. Before the rainstorm (about 1 day), the air humidity is high, and it also comes out during the day. This abnormal surface is now in line with the folk proverb "Toad comes out of the hole during the day, and it will rain". 4. fish. Fish live by breathing oxygen dissolved in water. On a sunny day; High atmospheric pressure; A large amount of oxygen is dissolved in water; So it quietly sank to the bottom of the water. Before it rains, the air pressure is low, the oxygen in the deep water is greatly reduced, and the fish float to the surface to breathe, so there is a saying that "when a fish dives, it will rain". 5. swallow it. There is a folk saying that it rains when swallows fly low. This is because swallows eat worms. When it rains, there is a lot of water vapor in the air, which makes some insects' wings wet, just like an airplane is too heavy to fly, but it has to fly, so it can only fly close to the ground. Secondly, when the weather turns rainy, the air pressure will become lower, the water vapor in the air will increase, and some insects in the soil will crawl out of the soil. If they swallow, they will fly very low to catch insects to eat. 6. snakes. Most snakes hide in caves during the day and go out for food, water, bathing and molting at night. However, when the weather is particularly humid and sultry, holes will also be forced. Therefore, it is a sign of rain when a snake comes out of the hole during the day, especially in late autumn and early winter. It is already cold, and when a big snake comes out of the hole, it will rain in a day or two. It is a verification of "the big snake comes out of the hole and it rains" and "the snake gallery rains". 7. Chicken. "The chicken stayed late, and it was rainy." Chicken has no sweat glands and sebaceous glands, so it has insufficient heat dissipation ability and is very afraid of heat. The suitable temperature for adult chickens is 20℃. If it exceeds 30℃, always open your mouth and spread your wings to help dissipate heat. In the hot summer evening, it was even more stuffy in the chicken coop, so it was found that the chickens had been reluctant to enter the coop for a long time, which was a sign that a thunderstorm was coming. "Swallows are humble and wear suǒ clothes." This is because swallows mainly feed on insects. When the weather turns bad and it's going to rain, the air humidity increases, and the wings of the bugs become soft with the water drops, so they can't fly high. Swallows fly low to catch insects. When a crow perches on a branch, its head always faces the wind. Because following the wind can make crows' feathers fluffy. Therefore, in the morning when the ground wind is very weak, we can determine the wind direction in the air by observing the direction of the crow's head resting on the high branches. At night, chickens don't want to go into cages, which is a sign of rain. Because the insects that lived in the cave before the rain climbed out of the ground and attached to the grass leaves because of the sweltering heat, this gave the chickens a good opportunity to feed. Contrary to chickens, when the weather is going to get bad, ducks enter the nest early because their habits like high temperature and high humidity. Goose birds sing different songs in different weather. The weather is fine, it's "goo goo, …" with a clear voice and no procrastination. When it is going to rain, even the sound of "Goo Goo, ..." is heavy and long. When the weather is about to turn to rain, the yellow bird will make a meow like a cat. In summer and autumn, at sunrise or dusk, owls bark two or three times and jump around the branches. They are restless and their voices are as low as crying. This is a celestial phenomenon, and it will rain. Bees are best suited to fly in clear weather and high pressure. In addition, the better the weather, the more sweet juice secreted by plant stamens, and the greater the ability to attract bees. In the morning, bees leave their nests to collect honey. The weather is fine. Don't go back to the nest at night, and it will continue to be sunny tomorrow. On the contrary, it indicates that rain will come. The cicada's cry is made by the vibration of the membrane of its abdominal sound generator. Generally speaking, cicadas cry about 2 hours before the rain turns sunny in summer, and don't cry when it turns cloudy in sunny days. This is because before it rains, its pronunciation membrane is wet and the vibration is invalid. On the contrary, the weather is getting better, the air is dry and the film vibrates strongly. When the weather gets bad, the ants are very busy. Some of them are busy moving to high places, while others are carrying mud nests back and forth. Generally speaking, the higher the nest, the greater the precipitation. There is also a big black ant nest, which is often built higher in windy places the next day.