Three geese, three stories of travelers. The greylag goose breeds in northern Europe, and many spend the winter in Andalusian wetlands such as Doñana. It is the ancestor of the domestic goose, and it was with greylags that the scientist Konrad Lorenz discovered that goslings follow the first creature they see when they hatch. He himself had greylags that followed him everywhere. The bar-headed goose, with its white head and two black stripes, is a true mountaineer: it crosses the Himalayas flying at more than seven thousand meters, where the air has hardly any oxygen. And the emperor goose lives on the icy coasts of the Bering Sea. Its white head is often stained rust-colored by the iron in the waters where it feeds. All three form pairs for life and fly in a V formation, taking turns at the front. Teamwork at thousands of meters.