Many species have enlarged pelvic fins as well and are known as four-winged flying fish. The process of taking flight, or gliding, begins by gaining great velocity underwater, about 37 miles per hour.

Imagine a fish so desperate to survive that it takes flight above the waves, using the open air as its last line of defense.

At the right moment, large wing-like pectorals (which were held close to the body when the fish was submerged) are extended. The fish gains lift and becomes airborne. Some flying fish also have large ...