Understanding the definition of Migration:-Few animals tend to change places in search of food and warmth.Many of the birds and several animals like elephants migrate to other places.This behavior of animals is known as migration.
Migration happens due to several reasons but not all birds migrate.There are about 10000 species of birds in the world ,out of these about 4000 species of birds migrate.The most famous migrants are long distance migrants.Birds like swallows are born in Europe but they spend their winters in Africa.Few birds migrate to avoid extreme winter whereas few other birds migrate to find food.
