The Structure of Birds' Feathers
The most important difference that distinguishes birds from other creatures is surely their ability to fly. Birds can fly by means of their feathers, which in fact have a very special structure.
A bird feather is a light structure that has lift force and can easily regain its original shape. If we examine a bird's feather under a microscope, we see a marvelous creation. In the middle part of the feather is a hard central shaft with a series of paired branches called barbs on either side. These barbs, whose lengths and softness vary, enable the bird to fly in the air.
As we examine the subject in further detail, we encounter even more interesting structures. Minute hairs called "barbules" project from each barb. Barbules cannot be seen with the naked eye. On these barbules are little hooks. The barbules are interlocked by these hooks, just like a zipper.
The hooks are clamped together like the two rows of a zipper. The barbules held together by hooks are so close to each other that not even smoke can pass through them. If these hooks are somehow unlocked, it is enough for the bird to shake itself or to put its feathers in order with its beak, to make the feathers return to their previous state.
In order to survive, birds must always keep their feathers clean, neat and ready for use. For the care of their feathers, they use oil sacs at the bottom of their tails. They take some oil with their beak, and then clean and polish their feathers. In swimming birds, this oil prevents water from reaching their skin when they are in the water or in the rain.
In addition, birds can prevent loss of body heat by ruffling their feathers in cold weather. In hot weather, on the other hand, they keep their body cool by smoothing their feathers.
Each group of feathers in a particular part of the body has particular functions. For example the down feathers and the feathers that lie along the wings and tail have different structures. Large tail feathers are used for steering as well as for braking. As the wing feathers are spread wide while flying, the surface area is expanded and lift force increased.
When the bird flaps its wing downwards, these feathers come closer and prevent air passing through. As the wings move up, the feathers open wide and permit air to pass through them. In order to maintain their ability to fly, birds shed their feathers at certain times of the year. Large torn or worn out feathers that do not function properly any more are renewed quickly.
This detailed structure exists in the feathers of every bird. All of them have the features that enable birds to fly. One who reflects on what is explained here and uses his intellect will notice the spectacular attributes in birds and will realize that these are Allah's creation. Just thinking about the attributes of birds alone is enough to understand that Allah is almighty.
It is stated in the Qur'an that believers reflect on the creation by Allah:
The kingdom of the heavens and earth belongs to Allah. Allah has power over all things. In the creation of the heavens and the earth, and the alternation of night and day, there are Signs for people with intelligence: those who remember Allah, standing, sitting and lying on their sides, and reflect on the creation of the heavens and the earth (and say): 'Our Lord, You have not created this for nothing. Glory be to You! So safeguard us from the punishment of the Fire. (Surah Al 'Imran: 189-191)