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Notis: Det följande är en reproduktion av artiklen
"Birds as marvels of God."
Structure and Flight
Do they not see the birds committed to
fly in the atmosphere of the sky? None holds them up in the air except God.
This should be (sufficient) proof for people who believe.
(16:79)
That birds can fly and so
efficiently is miraculous. In order to work, such a flying machine must be
amazingly lightweight and yet incredibly tough and strong. To take off and
maintain flight, the bird can’t be too heavy. Yet to survive the conditions
faced in the air and the force of landing, it must be tough so as not to break
on impact. These two qualities (lightness and toughness) are exactly how a bird
is constructed.
The skeletal framework of a bird is rigidly interconnected with a
very sturdy spinal column of fused verte-brae. The neck is strong but incredibly
flexible as it must have the strength to support the head (keeping it
motion-less when in flight) yet flexible and ready to swing it suddenly in any
di-rection, bending far downward or up-ward to spot prey or predators. The
number of vertebrae in a bird’s neck varies from long-necked to short-necked
birds. This may sound obvi-ous. But a mouse has the same num-ber of cervical
vertebrae as a giraffe (seven). Birds have a minimum of 11. Flexibility of the
neck is achieved by a system of long bands of muscles and smaller muscles that
are perfectly co-ordinated. From the slow turning of an owl’s head to the flash
of a heron catching a fish, it’s a masterful ma-chine.
Bones in the bird are hollow and thin-walled for lightness with
internal struts for support. All weight is con-centrated toward the center of
the bird. At that center is a very large breastbone to which are attached the
pectoral muscles, the mighty muscles which drive the wings. Flight muscles may
account for 25-30 percent of a bird’s weight, compared to pectoral muscles in
the human which weigh less than one percent of total weight. These muscles
working to drive the wings build up great heat. To coun-teract this, the bird
has the most effi-cient respiratory system of any verte-brate. Rather than a
single pair of lungs the bird has a system of air sacs throughout the body even
in some of the hollow spaces in the bones. The air is taken in quickly to all
important parts of the body and the bird’s faster heartbeat provides rapid
circulation.
Good eyesight is an important prereq-uisite of flight. A bird
relies more heavily on vision than most animals. In some birds their eyes
actually weigh more than their brains. Birds can see distant things as much as
eight times more clearly than man can, and they also see close up much better.
Most birds have both monocu-lar and binocular vision. They can rely on what one
eye sees close up and then count on sharper binocular vi-sion for distances.
Have they not seen the birds above them
lined up in columns and spreading their wings? The Most Gracious is the One who
holds them in the air. He is Seer of all things. (67:19)
Most important to flight are the wings and feathers. The wing is
really an arm with a large ball joint fitting into the socket in the shoulder.
This is a specialized joint allowing great mo-bility. The way the bird can
rotate as well as flap up and down gives the bird the ability to maneuver, slow
down, change direction suddenly and land gracefully.
The feather is a unique and wonderful creation. It’s light yet
sturdy, flexible, versatile and easy to care for, provides cushioning, thermal
insulation, and is water repellent and replaceable. Bright colored feathers are
important in some bird species for attracting a mate and for territorial
displays. Some birds have feathers camouflaged like their surroundings to help
them hide.
The simple looking feather is actually a very complex mechanism.
There is a center shaft attached to the skin. From this project many parallel
branches or barbs which in turn bear smaller bar-bules, which are equipped with
hooks and barbs. All of these barbs catch in one another like little zippers
forming a smooth surface. If the feather is ruf-fled and the connection broken,
it’s easily smoothed out and rehooked. On each feather there are millions of
these barbules hooking the feather to-gether. When the wings are folded the
feathers lie over one another like roof shingles with air spaces between to
insulate against heat loss.
With all the bird does, there is con-tinuous wear and tear on the
feathers, so they must be replaceable. That’s why birds molt on a regular basis.
Molting is a precise process, triggered in the least severe season. The
feath-ers are discarded usually in pairs (one from the right side and the
corre-sponding one from the left). And never so many that the bird can’t fly,
although it may be weakened. To compensate the new feathers grow in very fast.
None holds the birds in the air except God
God holds them in the air. God gives them the physical
construction to fly, the use of wings. They can raise and lower the wings, can
move them for-ward or back, they can reduce the wing area, can rotate the wing
at the shoulder, can twist the wings. Then God gives them the instincts to know
how to do it. Birds don’t study the laws of gravity but they use them. From
great heights, they’ll tuck their wings and fall straight down, then pull out
the wings to provide resis-tance to slow down and land. They make it look easy.
Hummingbirds can fly backwards. Penguins, who don’t fly, use their
wings like a powerful oar to move quickly through the water. Hawks can turn
upside down in full flight to catch smaller birds trying to escape, then right
themselves and fly on with-out missing a beat.
Birds use the wind with great skill, as if they studied science.
Some birds use land drafts to soar and glide, like an eagle using the currents
in a canyon. Over water, seabirds are incredibly adept at using drafts. Gulls
also have the instinct to use obstacles, like ships, which create extra
updrafts. They’ll follow motionless, looking as if they’re tied like a kite on a
string.
The structure of the bird and the miracle of flight are signs from
God if we choose to see them. This is a proof for people who believe.
The Mystery Of Migration
Have they not seen the birds above them
lined up in columns and spreading their wings? The Most Gracious is the One who
holds them in the air. He is Seer of all things. (67:19)
Certainly of all things
about birds, one of the most incredible is migration. In ancient times, all
kinds of strange explanations were advanced to explain why certain birds
disappeared in certain seasons. It was believed swallows spent the winter
sleeping at the bottom of lakes. Aristotle announced that the European robin
changed into another bird, the European redstart, at the approach of summer, and
then presumably back into a robin. The Romans generally agreed, but claimed
swallows turned into frogs. In 1703 an Englishman wrote that birds flew to the
moon taking 60 days to get there and then on arrival finding no nourishment went
into hibernation.
We now know that when birds disap-pear from one location it is
because they migrate. We know when they go, which birds go where, over what
route. Some are truly incredible jour-neys. The sandpiper goes from Can-ada to
Tierro del Fuego. The golden plover travels from the arctic to the pampas of
Argentina. Some barn swallows go 9000 miles from Alaska to Patagonia.
Scandinavian swallows end up at the southern tip of Africa. Little warblers
weighing less than an ounce take solitary night journeys from Germany to central
Africa. The arctic tern is the champion long dis-tance flyer, going between 10
and 14 thousand miles in its migration, breeding at the North Pole and
win-tering in Antarctica.
Those are the things we know. What still baffles scientists is the
how. What prompts them to start when they start and to return when they return?
And how do they find their way? For each new theory advanced, tests were
per-formed which disproved it. Do they use landmarks? A species of stork when
migrating south through the North American plains makes an abrupt turn to the
west at approxi-mately Great Falls, Montana to cross the Rockies. But it
couldn’t be land-marks, because birds cross vast stretches of ocean to remote
islands. The golden plover travels over 2000 miles from Alaska to Hawaii over
open seas. Some curlews go 6000 miles from Alaska to Tahiti with no landmarks to
follow.
Birds use the position of the sun. Ex-periments with birds in
cages showed that they would orient themselves to the sun and become confused by
mir-rors changing the sun’s position. Yet many species of birds migrate by
night. They then must use the stars. But while it’s true that birds rarely start
out on a cloudy night, they will continue their migration even if clouds obscure
the stars.
It is generally acknowledged now that all these factors apply.
Birds do use the sun by day and the stars at night and also the earth’s magnetic
field, perhaps also wind currents, land-marks and deep ocean sound vibra-tions.
How they use these things re-mains a puzzle.
And how do they know where to go? In an experiment a bird was
carried from its burrow in Wales to Boston, Mass. and released. Within two
weeks, it was back in its burrow, 3000 miles across the Atlantic, totally
un-familiar territory. The bronze cuckoo of New Zealand is raised by foster
parents who do not migrate, yet the young cuckoo migrates over 2500 miles of
open ocean to the Solomon Islands for its first winter.
They must carry within them a "map," which shows them
instinc-tively the route and the destination. And they must also have within
them an internal clock that tells them when to leave. The swallows return to
Cap-istrano on the same day each year and the vultures to Hinkley, Ohio (so man
can marvel and turn it into an event.)
Migration is an amazing phenome-non. It’s a difficult journey and
many perish, providing food supplies for other animals along the migration
route. A Mediterranean falcon lays its eggs later in the season than any other
bird so it can feed its young off the migration of other birds.
To help conserve energy and insure that the most individuals
complete the trip many birds fly in formation. The beautiful V-shape of the
Canada goose and others is the most efficient use of drafting. It saves a lot of
energy for the whole flock, each bird able to rest on the air currents created.
Who teaches them that?
Do you not realize that everyone in the
heavens and the earth glorifies God, even the birds as they fly in a column?
Each knows its prayer and its glorification. God is fully aware of everything
they do. (24:41)
While the ornithologists and scientists struggle and experiment
and test out theories, we know the truth. A bird flies because God is the One
who holds it in the air. It migrates along mysterious routes because it follows
God’s plan. Its flight is part of its glo-rification of its Creator.
The robin doesn’t wish it were an ea-gle. The crow doesn’t care
that he’s not colorful like the cardinal. The hummingbird doesn’t want to try
fish for change like the duck.
That’s a lesson for us. A sign for people who understand and take
heed. Our job is to worship God alone. If we can do that job even a fraction as
well as birds do their jobs, we might just be fortunate enough to fly with them
in heaven.
Lydia Kelley
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