Âm thanh chia sẻ

This bird… flies where most animals can’t survive. Above the clouds. Above the mountains. Where oxygen is almost gone. This is the bar-headed goose. And it crosses the Himalayas. Reaching heights over 7,000 meters. Where the air is thin… and every wingbeat costs more. So how does it survive? Its lungs are different. More efficient. Pulling oxygen from air most animals can’t use. Its blood… carries oxygen faster. Fueling muscles in extreme conditions. Even its wings beat in a way