Born to Fly
by:
George Vandeman
The construction of a fighter plane is incredibly precise. The type of wing. The sweep of the wing. The structure of the tail. The engine housing. And of course the weight. All must be right-- if it is to fly.
But did you know that the tiny sparrow in your back yard has been constructed even more precisely--for flight?
A sparrow is not worth much, by some standards. In the days of Christ, you could buy two of them for a farthing. Yet Jesus said that not one of them falls to the ground without our Father's notice.
And we say, "That's love. That's care. You'd expect a loving God to notice even a insignificant sparrow."
But did you know that a sparrow has already had considerable attention, long before it first takes to the sky? In fact, it seems evident that God used as much care in constructing the sparrow as He did in creating the world.
You see, sparrows were never meant to fall to the ground. They were designed for flight, the same as most other birds. A notable exception is penguins, which are superbly designed for "flying" in water.
According to an ancient Greek myth, an Athenian man named Daedalus and hes son Icarus both fell out of favor with the king of Crete. They were exiled on a small island in the Mediterranean Sea. Naturally they sought some way to escape.
As the story goes, Daedalus carefully studied the design of the wings of sea birds. Then he made two pairs of wings out of wax and feathers, and these wings enabled them to escape from the island. But it all ended in disaster when Icarus, excited with his new ability, flew too near the sun. The poet describes it thus:
With melting wax and loosing strings
Sank hapless Icarus on unfaithful wings.
Hundreds of years passed before man really did fly, but it was not by attaching wings to his body. A man simply is not designed to fly. And it would take more than wings to change the situation.
For one thing, the breast muscles that operate a man's shoulders and arms contain less that 1 percent of his total body weight. In birds those muscles make up as much as 30 percent of the total body weight.
For another thing, the bones of a bird are extremely light. They are also hollow and full of warm, buoyant air. For instance, although a man-o'-war bird has a wingspan of about seven feet, its bones weigh only four or five ounces. Think of it-- its feathers actually weigh more that its skeleton! And feathers are light, you know.
Yet in spite of the lightness of a bird's bones, they are unusually flexible and strong. These features are essential for withstanding the stresses and strains of flight.
You realize, of course, that tremendous energy is demanded for flight. But here again birds are well equipped. They have the highest body temperatures of any animal. This high temperature, along with an efficient digestive system and rapid circulation, means that birds can utilize an unusually high percentage of the food they eat.
Someone has calculated that the golden plover is so efficient it can migrate thousands of miles across the ocean from Labrador to the central part of South America with the loss of only about two ounces of body weight. If a small airplane did as well, it would go about 160 miles on a gallon of gasoline instead of 20 miles as it now does!
Of course, there must be rapid delivery of energy to the breast muscles. But nothing is overlooked. Birds have a higher blood pressure than men, and blood-sugar concentrations are about twice that of mammals. Birds with little use for their wings, such as domestic chickens, have a relatively poor blood supply to the breast muscles. That is why the breast meat is pale in color. But strong fliers have good circulation in these muscles, and in them the muscles are dark red.
For flight there must be keen eyesight. But that is also cared for. In some hawks and other birds of prey, vision is eight to ten times more efficient than in humans. This does not mean that hawks have telescopic vision. But it does mean that their eyes have an almost incredible resolving power. The most sensitive part of a hawk's eye contains up to 1.5 million visual cells--in contrast to only 200,000 in a man's eye. You can see why a hawk is able to distinguish detail.
A birds' feathers are amazingly structured for protection against heat and cold, for fanning the air, and for streamlining the body. And every slight change in position of a feather during flight is designed to absorb energy from the air and use it effectively. It is estimated that, for their weight, feathers are stronger than material made by man. Below the contour feathers of the body, many birds are provided with an undercoat of soft feathers that serve as insulation.
If you inspect the construction of a single wing feather under a microscope, you will see a truly marvelous design. That feather is extremely complex in both structure and function. We are told that a single pigeon primary wing feather has more than a million parts. There are vanes and barbs and barbules and flanges and tiny hooks, and they all work together to form a natural zipper. When the zipper comes open, it can be zipped up again by preening.
There is even more. As a bird flies, every slight change in air flow is automatically compensated. The flight feathers of the wing tip act like the propeller of an airplane. They change pitch in response to the changing stresses that the air exerts upon them. The base part of the wing acts like the wing of a plane. And the secondary and tertiary wing feathers function as flaps.
But now listen. Embedded in the skin near the quill of each flight feather are nerve endings that actually convert the feathers into sensory receptors. They record the precise position of every feather. Then, by way of the spinal cord, they bring about continuous adjustment in the more than twelve thousand tiny muscles attached to the base of the feathers!
But that still is not everything. The precise body position of the bird is recorded by the semicircular canals of the inner ear. And the inner ear reports the changing conditions to the cerebellum of the bird's brain. What do you think of that?
When you watch a bird in flight, it is impossible to tell what all is going on. The form of the wing is constantly changing. And of course we cannot see the internal muscular movements.
In general, the larger the bird, the slower it flaps its wings. A hummingbird vibrates its wings about fifty times per second, and a heron only about two times. Taking off and landing naturally demand the greatest energy and coordination.
Gliding flight is much like a toboggan sliding downhill, except that the bird is sliding on air instead of on snow. Here is how it works. If a bird is gliding down an air slope and losing altitude at the rate of ten feet per second-- but the air that contains the air slope is rising ten feet per second-- the bird will glide along in level flight. And of course if the air is rising faster than the bird is gliding downhill, the bird will gain altitude without any effort.
If the wind speed equals the forward and downward speed of a gliding bird, the bird will appear to stand still. It is as if a man were walking down a moving stairway at the same speed the stairs move up. His progress in space is zero.
You may have noticed soaring birds with their wing tips spread like fingers on a hand. This is called slotting. It serves to reduce turbulence behind the wings when the wings are tilted downward. This is necessary when a bird is coming in for a landing.
Then there are the helicopter actions of some birds--vertical, reverse, and hovering flight. These are extremely complicated maneuvers that we do not fully understand. We do know that these acrobats of the air use not only a powered downstroke but also a powered upstroke.
All these facts are absolutely amazing. Birds-- whether sparrows or hummingbirds, hawks or eagles-- are born to fly. They are fantastically equipped to fly. They are intricately made to fly!
And right here I would like to thank my friend, the ornithologist Dr. Asa Thoresen, for all this fascinating information about birds.
Is it any wonder that God challenged ancient Job with questions about birds? "Doth the hawk fly by thy wisdom, and stretch her wings toward the south? Doth the eagle mount up at thy command, and make her nest on high? She dwelleth and abideth on the rock, upon the crag she seeketh the prey, and her eyes behold afar off. . . .And where the slain are, there is she"(Job 39:26-30).
Did all this come about by chance? Did birds just develop all these capabilities over long ages? Did their fantastic equipment for flight come about little by little?
Think it through. Suppose a bird had the right kind of wings but his breast muscles were weak. Would he be able to fly? What if he had no way of rapidly supplying energy to those muscles? Could he fly? What would happen if the bird had poor eyesight?
What if a bird's feathers were simply constructed--like scales on a fish or a reptile, for instance? What if the feathers did not allow constant changes in the form of the wings? And what if these changes were not recorded in the inner ear and sent to the brain for perfect coordination? If even one piece of the bird's equipment were missing or undeveloped, could he fly?
In other words, if a bird had some of the necessary flight equipment but not all of it, could he function some way in the meantime while he waited for the missing equipment to develop? No. He needs it all at once. He has to be born that way. He has to be made that way. And that, my friend, is not evolution. It is creation! It is "in the beginning God"!
It was Job, you recall, who suggested, "Ask . . . the fowls of the air, and they shall tell thee"(Job 12:7).
Ask the birds. Watch them in flight. Study the way they are made. The message is too clear to be missed. There is a God. There is a Creator. There is meaning to life. The birds did not just happen. No bird is the product of blind, meaningless, mindless, haphazard chance. And neither are we!
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Well, I thought that was really good!!!! I hope you enjoyed reading it!
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