Birds fly in a V formation for a few reasons.

• It helps them to conserve energy. When a bird flies behind another bird, it can ride in the updraft that is created by the leading bird’s wings. This reduces the amount of energy that the bird needs to flap its wings, which can save them a significant amount of energy over long distances.
• It helps them to stay oriented. The V formation helps the birds to stay in line and follow the leader. This is especially important when the birds are flying in poor visibility, such as at night or during fog.
• It helps them to communicate. The birds in the formation can communicate with each other by using their calls and body language. This helps them to stay together and avoid obstacles.

Not all birds fly in a V formation. Some birds, such as hummingbirds and sparrows, are too small to benefit from flying in formation. Other birds, such as pelicans, may fly in a V formation when they are migrating, but they may fly in other formations at other times.

The V formation is a fascinating example of how animals have adapted to their environment. By flying in formation, birds can conserve energy, stay oriented, and communicate with each other. This helps them to make long migrations more efficiently and safely.