Do birds have to emigrate?

We know that many animals don't stay in one place. Birds, fish and other animals migrate from one place to another at a specific time. They have different reasons: it is easier for most of them to turn to find food, but others move to get rid of too dense places.

When it is cold, many birds migrate to warm places to look for food. Feed some fish in warm water and then move them to cold water for delivery. The most famous migration (migration) is probably the migration of fish, which is called "salmon". This kind of fish is born in fresh water, but many swim for miles in salt water. The life span of flowers there. When it gets old, it goes back to its birthplace, Danshui. Then, inoculation molding. In northern Europe, there is a rat class. The mountains became too crowded when they left home. They moved to the lowlands. Sometimes they will walk all the way to the seaside, and many will die and fall into the sea.

Recently, scientists have studied an immigrant lobster (lobster). Every year,

The weather is bad, the season is coming, the lobster enters the long line and starts to walk.

Cross the sea floor. No one knows why they did it, and no one knows where they are going.

Therefore, sometimes we know why people and animals go from one place to another, but in other places.

Sometimes we don't. Maybe everything is the same.