Birds' migration habits are as unique as they are. Some birds fly solo, others in groups, but perhaps what is most commonly recognized by the average non-birder is the V formation. Linear flight formations like the V are called echelons. Interestingly, the V formation is actually not as common as the J formation. For years researchers were puzzled by this flight behavior. Now, it is widely accepted by scientists that the V formation serves an aerodynamic purpose; each bird's upwash vortex fields help the one behind it fly faster with less effort.

Research conducted with photography and using fluid dynamics and energy wave configuration calculations show that no matter where the V pattern occurs, it usually provides the biggest energy advantage. Other factors influence the pattern, particularly communication needs.  Scientists also believe that vision is important in determining a bird's position in the group. Each bird is at an angle so that he or she doesn't block the eyesight of its neighbor. There is still little known about flock leaders are chosen. Data has yet to show a correlation between gender, age, size, or social status.