Craig Ramsey, age 11, of Gastonia, N.C., for his question:
HOW DO FLYING FISH FLY?
Flying fish certainly leave the water and take short trips through the air. The mystery is whether or not they flap their fins as birds flap their wings. This dispute raged for a long time, and both experts and non experts had their say. We now have evidence that these remarkable fish cannot flap like birds, though their gauzy fins may shiver and vibrate in the sparkling air.
The average flying fish pops unexpectedly out of the water, takes off at 40 miles per hour, skims over the waves for about 10 feet and plops back down. The whole thing happens in about 10 seconds, which is too fast for the human eye to see clearly. We merely catch a glimpse of a silvery blue body with gauzy butterfly fins. True, the shiny fins seem to beat the air. But even the ordinary movie camera cannot prove whether they do or not. The separate frames in the movie are too blurred.
The shivering motions of those gauzy wings called for stroboscopic photography. This type of camera takes a series of exposures at split second intervals. The separate pictures are precise and clear enough to show the slightest changes in a moving object.
Stroboscopic pictures prove that the flying fish is a glider and not a fin flapper. These results gave the fish experts a chance to say, "I told you so." They had examined the muscle structure of the flying fish. Birds need mighty chest muscles to flap their wings. But the flying fish does not have the right muscles for flapping.
Several species of flying fish live frantic lives in warm seas around the world. Our favorite is the four finned flying fish, often seen off the southern shores of California. He takes to the air like a shimmering silvery blue dragonfly 18 inches long. When underwater, he swims with his four wide fins folded to his side.
The trip upstairs is triggered below, when the fish swims frantically to escape a shark or some other hungry predator.
He darts to the surface, lashing his tail and vibrating his huge tail fin at perhaps 50 beats per second. For a moment he taxis along, then he spreads his fins and becomes airborne. The momentum from his last frantic swim carries him along for about 10 feet. In the air, sad to say, he may be grabbed by a greedy gull.
As he leaves the water, his lashing tail shakes his body and vibrates his gauzy fins. Wavelets and air currents
may make them flutter and the uncertain picture is blurred by the shiny fish in the sparkling air. To the human eye, the flying fish may seem to beat his fins, but careful researchers assure us that he does not.