migratory instinct

例句：

1. 1. The birds are migratory creatures that fly long distances to find food.
   这些鸟类是迁徙生物，它们会飞很长的距离去寻找食物。
2. 2.Many species of animals migrate to different parts of the world each year.
   每年，许多动物物种会迁移到世界的不同地方。
3. 3.Migratory birds play a crucial role in pollinating plants and spreading seeds.
   迁徙的鸟类在授粉和传播种子方面起着至关重要的作用。