Swallows fly to the south in winter. Where on earth are they flying to? Because it is cold in the north and warm in the south in winter, swallows will fly to warm areas in the south and return to the north in winter. Every winter, migratory birds fly to the south for the winter. Swallow is one of the familiar migratory birds, which can be seen everywhere in many parts of our country. Where they went to the south became a mystery. Most parts of China belong to temperate continental climate, with summer and winter, and the temperature in many places is very low in winter. All the insects died, and some went into hibernation. Swallows don't feed on crops like sparrows, so they face the problem of hunger. They can only fly to the warm south to continue their lives. The southern region where swallows fly in winter varies from place to place, and different regions have different definitions of the south. Swallows living near the equator don't have to fly to higher temperatures, because it's warm here and insects always exist, so they don't have to migrate all the year round. Swallows in the north will travel long distances to Yunnan, Sanya and other places for the winter before winter comes. Some swallows will fly to Southeast Asia and other countries for the winter, while European swallows will spend the winter. Will fly over the Sahara desert and come to distant southern Africa for the winter. The climate in the Sahara desert in Africa is very bad, and there are few people here. The only oasis provides water for wild animals, which will dehydrate them and die. Swallows only need to remember the oasis in the desert when they migrate. Because there will be a large number of mosquitoes living next to the water source here, as long as they get fresh water resources in their bodies, they can replenish energy and let themselves have the strength to continue flying. Through the research of scientists, it is found that swallows use the magnetic field lines to perceive the direction to identify the route and find their own home. In fact, as long as we observe carefully, we will find that swallows rarely walk on the ground, which is different from other birds. Mainly because of the unique body structure of swallows, the strength of swallows' legs is very small and they can't support the weight of their bodies for a long time. They can only fly for a long time, but fortunately, the food they eat is also flying. Therefore, swallows like eating mosquitoes, flies and other small insects very much. Swallows, like us, are monogamous. Husband and wife will build nests together, using mud, thatch, branches and the like, because this has a supporting effect, and the nest they live in is strong and safe. Swallows like to settle in places where humans live, mainly because humans rarely hurt swallows and make them feel safe. We used to see swallows everywhere in summer, but in recent years, we seldom see them. This shows that although swallows are not extinct, their numbers are definitely decreasing. First, the reduction of food, we all know that swallows mainly feed on insects, and their predation activities are carried out in the air. In modern society, the more people use pesticides, the fewer insects there are, so the number is decreasing. Second, the change of living environment. Swallows like rivers and tides and live in mud houses in the countryside. In recent years, the countryside is a small house, and there is less and less room for swallows to nest. I hope that human beings can learn from this painful experience and protect animals so that human beings will not become the last species on earth.