Remember when you were a kid and you looked up at the sky to see dozens of geese soaring overhead in a V shape? "Why do they do that?" you probably wondered. Seeing birds — from geese to pelicans and ...

From geese and pelicans to cranes and cormorants, many birds use a V-shaped flock to master the aerodynamics of long-distance flight. Here is the science behind this clever energy-saving strategy.

The dark, smudgy streaks on Xavi Bou's photographs suggest the jerky ink tracks created by a malfunctioning printer, but they actually record the various patterns birds trace while flying in flocks.