How Giant Birds Can Fly Nearly 10,000 Miles In One Go

Forget circumnavigating the globe in 80 days - an albatross can do it in a mere 46. These world travelers are among the largest flying birds, weighing up to 25 pounds (11 kilograms), and with a wingspan of 11 feet (3 meters).

But hefting such huge bodies off the ground takes a lot of energy. If albatrosses flew simply by flapping their wings, they would lose about half their body mass fueling that kind of flight. So how do these kings of the sky complete such long journeys so quickly?