A World on the Wing: The Global Odyssey of Migratory Birds

In the past two decades, our understanding of the navigational and physiological feats that enable birds to cross immense oceans, fly above the highest mountains, or remain in unbroken flight for months at a stretch has exploded. What we've learned of these key migrations is nothing short of extraordinary.



Bird migration entails almost unfathomable endurance, like a sparrow-sized sandpiper that will fly nonstop from Canada to Venezuela-the equivalent of running 126 consecutive marathons with...