Âm thanh chia sẻ

This bird… does something almost impossible. It sleeps… while flying. Not for minutes. For days. Even months. It’s called the common swift. And once it takes off… it can stay in the air for most of its life. Eating. Flying. Navigating storms. Without landing. But here’s the strangest part. Scientists believe it doesn’t fully sleep on the ground… during migration. Instead… it enters micro-sleeps. Brief moments where parts of its brain rest… while it keeps flying. Still moving.