20 Animal Journeys That Still Defy Explanation

A bird that weighs less than a nickel should not look like a long-distance athlete, but the ruby-throated hummingbird has never cared about appearances. Before migration, it feeds intensely and stores fat, turning a tiny body into a living fuel tank. Some cross the Gulf of Mexico in a nonstop flight that can cover roughly 500 miles, often at night and without a branch, fencepost, or feeder in sight. The risk is obvious. A bad storm or poor timing can turn the journey dangerous quickly.