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“Do they not see the birds committed
to fly in the atmosphere of the sky? No-one holds them up in the air except Allah. This should be (sufficient) proof for
people who believe”.
(Quran16:79)
 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
The skeletal framework of a bird is rigidly
interconnected with a very sturdy spinal column of fused
vertebrae. 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 direction, 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 obvious. But a mouse has the same number 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 machine.
Bones in the bird are hollow and thin-walled for lightness
with internal struts for support. All weight is concentrated
toward the centre of the bird. At that centre 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 counteract this, the bird has
the most efficient respiratory system of any vertebrate.
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.
Eyesight
Good eyesight is an important prerequisite
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 monocular and binocular
vision. They can rely on what one eye sees close up and then
count on sharper binocular vision 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."
(Quran 67:19)
Wings and Feathers
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 mobility. The way the bird
can rotate as well as flap up and down gives the bird the
ability to manoeuvre, 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 coloured 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 centre shaft attached to the skin.
From this project many parallel branches or barbs which in
turn bear smaller barbules, 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 ruffled and the connection broken, it’s
easily smoothed out and re-hooked. On each feather there are
millions of these barbules hooking the feather together.
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 continuous wear and tear on
the feathers, so they must be replaceable. That’s why
birds malt on a regular basis. Malting is a precise process,
triggered in the least severe season. The feathers are
discarded usually in pairs (one from the right side and the
corresponding one from the left). And never so many that the
bird can’t fly, although it may be weakened. To
compensate, new feathers grow in very fast.
No-one holds the birds in the air except Allah.
Allah holds them in the air. Allah 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
Allah 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 resistance 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 without missing a beat.
The Wind
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 Allah if we choose to see them. This is a proof
for people who believe.
Provided with kind permission from; IFSA
Mailing list, Islamic Forum for Science and the Arts.
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