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Signs Of God, Design In Nature
A thorough examination of the feathers of a bird, the sonar system of a bat or the wing structure of a fly...

Futuyma's Bosphorus Errors
A conference was recently
held at the Bosphorus
University (BU) in Istanbul,
following another held at
the Middle East Technical
University (METU), Turkey,
to which the State University of New York's
evolutionary biologist
Douglas J. Futuyma was
invited as a guest of the
METU Biology Department
teaching staff member
Aykut Kence.

Home page > Animal Kingdom > Flawless Flying Machines: Birds

Animal Kingdom

eagleBecause they believe that the birds must have somehow evolved, evolutionists assert that birds are descendants of reptiles. However, the progressive model of evolution cannot explain any of the body mechanisms of birds, which have a completely different structure from mammals. First, the primary feature of birds, i.e. wings, is a great obstacle for the theory of evolution to explain. One of the Turkish evolutionists, Engin Korur, makes the following confession in reference to the impossibility of the evolution of wings:

The common trait of eyes and the wings is that they can only function if they are fully developed. In other words, a halfway-developed eye cannot see and a bird with half-formed wings cannot fly. How these organs came into being is one of those mysteries of nature that has still to be accounted for. 1

The question of how the flawless structure of wings might have been formed through a series of consecutive random mutations remains completely unanswered. The process in which the front leg of a reptile could transform into a flawless wing seems to be as inexplicable as ever.

Furthermore, the existence of wings is not the only prerequisite for a land creature to become a bird. Mammals totally lack a number of mechanisms that are used by birds in flying. For example, the bones of birds are considerably lighter than those of mammals. Their lungs are of a different structure and function as well as are their skeletal and muscular structures. Their circulatory systems are much more specialised than those of mammals. All of these mechanisms could not possibly come into existence over time through an "accumulative process". Assertions of the transformation of mammals into birds are, therefore, only nonsensical claims.

Structure of Bird Feathers

The theory of evolution, which claims that birds are descendants of reptiles, is not able to explain the colossal differences between these two classes of beings. Birds display properties distinct from reptiles in having a skeletal structure composed of hollow, extremely lightweight bones, and a unique respiratory system and in being warm-blooded creatures. Another structure unique to birds, which places an unbridgeable gap between birds and reptiles, is the feather.


Feathers are the most important of the interesting aesthetical aspects of birds. The phrase "light as a feather" depicts the perfection in the intricate structure of a feather. 2

Feathers are constructed of a protein substance called keratin. Keratin is a hard and durable material that is formed by the old cells that migrate away from the nutrient and oxygen sources in the deeper layers of the skin and die in order to give way to new cells.

The design in bird feathers is so complex that the process of evolution simply cannot explain it. Scientist Alan Feduccia says feathers "have an almost magical structural complexity" which "allows a mechanical aerodynamic refinement never achieved by other means".14 Although he is an evolutionist, Feduccia also admits that "feathers are a near-perfect adaptation for flight" because they are lightweight, strong, aedodynamically shaped, and have an intricate structure of barbs and hooks. 3

The design of feathers also compelled Charles Darwin ponder them. Moreover, the perfect aesthetics of the peacock's feathers had made him "sick" (his own words). In a letter he wrote to Asa Gray on April 3, 1860, he said "I remember well the time when the thought of the eye made me cold all over, but I have got over this stage of complaint..." And then continued:

... and now trifling particulars of structure often make me very uncomfortable. The sight of a feather in a peacock's tail, whenever I gaze at it, makes me sick! 4

Small Barbs and Hooklets

barb and hookletsOne encounters an incredible design if the feather of a bird is examined under the microscope. As we all know, there is a shaft that runs up the centre of the feather. Hundreds of small barbs grow on either side of this shaft. Barbs of varying softness and size give the bird its aerodynamic nature. Furthermore, each barb has thousands of even smaller strands attached to them called barbules, which cannot be observed with the naked eye. These barbules are locked together with hooklike hamuli. The barbules hold on to one another like a zip with the help of these hooklets. For example, just one crane feather has about 650 barbs on each side of the shaft. About 600 barbules branch off each of the barbs. Each one of these barbules are locked together with 390 hooklets. The hooks latch together as do the teeth on both sides of a zip. These barbules interlock so tightly that even smoke blown at the feather cannot penetrate through it. If the hooklets come apart for any reason, the bird can easily restore the feathers to their original form by either shaking itself or by straightening its feathers out with its beak.

In order to survive, birds have to keep their feathers clean, well-groomed and always ready for flight. They use an oil-gland located at the base of their tails for the maintenance of their feathers. They clean and polish their feathers by means of this oil, which also provides water proofing when they are swimming, diving or walking and flying in rain.

In addition, in cold weather the feathers prevent the body temperature of birds from falling. The feathers are pressed closer to the body in hot weather in order to keep it cool. 5

Feathers spring from a hollow cylindrical structure of the skin. A chick that is 2-3 hours old primarily has feathers for warmth.

Types of Feather

Feathers take on different functions depending on where on the body they are located. The feathers on a bird's body have different properties from those on the wings or tail. The full-feathered tail functions to steer and brake. On the other hand, wing feathers have a distinct structure that enables the surface area to expand during beating in order to increase forces of up-lift. When the wing is flapped downward, the feathers come closer together, preventing the through passage of air. When the wing is in an upward movement the feathers open up, to give way to the passage of air. 6 Birds shed their feathers during certain periods in order to maintain their abilities to fly. Worn or damaged large feathers are renewed immediately.

bird flying
This serial motion depicts various phases in a sparrow's flight: take-off, short flight and landing.
bird flying
Old feathers of birds are replaced with new ones with different frequencies in different species. The renewal of feathers is called moulting, which happens before migration.


Due to the curvature of the wing, air pressure on the upper surface is weaker than on the under surface, which in turn lifts the bird into the air (bottom left). If the wing is curved, further airflow at the top increases the pressure creating a downward force. This way the bird stalls (right bottom). falcon wing
bird's wings
Yellow lines indicate the curvature of the wing.
The wing of a falcon


A close examination of birds reveals that they are designed specifically for flying. The body has been created with air-sacs and hollow bones in order to reduce body mass and overall weight. The fluid nature of their wastes ensures that excess water in the body is disposed of. Feathers are extremely light structures in comparison to their volume.

Let us examine these special structures of birds one by one:

1- The skeleton

bird skeleton
Bird bones are extremely light but sturdy, largely because they are hollow. There is air inside the cavities where supporting bars stiffen the bones. These hollow bones are the main inspirations for the design of modern aeroplane wings.

The strength of a bird's skeleton is more than adequate even though the bones are hollow. For example, a hawfinch 7 inches long (18 cm) exerts about 151 lbs. (68.5 kg) pressure in order to crack open an olive seed. Better "organised" than mammals, the shoulder, hip and chest bones of birds are fused together. This design improves the strength of the bird's structure. Another feature of the skeleton of birds, as mentioned previously, is that it is lighter than in all other mammals. For instance, the skeleton of the dove weighs only about 4.4% of its total body weight. The bones of the frigate bird weigh 118 gr, which is less than the total weight of its feathers.

2- Respiratory System

Birds have a very different anatomy from their alleged ancestors, the reptiles. Bird lungs operate in a completely different fashion from those of mammals. Mammals inhale and exhale air through the same windpipe. In birds, however, the air enters and exits through opposite ends. A special "design" such as this has been created to provide for the high volumes of air needed during flight. Evolution of such a structure from that of reptiles is not possible.

The respiratory system of mammals and birds operate on completely different principles, primarily because birds need oxygen in much greater quantities than do mammals. For example, a certain bird could require up to twenty times the amount of oxygen necessary for humans. Therefore, the lungs of mammals cannot provide oxygen in the quantities required by birds. This is why the lungs of birds are created upon a much different design.

Unidirectional airflow in the bird's lungs is facilitated by a system of air-sacs. These sacs collect air and then pump it regularly into the lung. In this way, there is always fresh air in the lungs. A complex respiratory system such as this has been created to satisfy birds' needs for high quantities of oxygen.

In mammals, air flow is bidirectional: air travels through a network of channels, and stops at the small air sacs. Oxygen-carbon dioxide exchange takes place here. Used air follows a reverse course in leaving the lung and is discharged through the windpipe.

On contrary, in birds, air flow is unidirectional. New air comes in one end, and the used air goes out the other end. This provides an uninterrupted supply of oxygen for birds, which satisfies their need for high levels of energy. Michael Denton, an Australian biochemist and a well-known critic of Darwinism, explains the avian lung in this way:

In the case of birds, the major bronchi break down into tiny tubes which permeate the lung tissue. These so-called parabronchi eventually join up together again, forming a true circulatory system so that air flows in one direction through the lungs…. Although air sacs occur in certain reptilian groups, the structure of the lung in birds and the overall functioning of the respiratory system is quite unique. No lung in any other vertebrate species is known which in any way approaches the avian system. Moreover, it is identical in all essential details in birds… 7

In his book A Theory in Crisis, Michael Denton also points out to the impossibility of formation of such a perfect system through progressive evolution:

Just how such an utterly different respiratory system could have evolved gradually from the standard vertebrate design is fantastically difficult to envisage, especially bearing in mind that the maintenance of respiratory function is absolutely vital to the life of an organism to the extent that the slightest malfunction leads to death within minutes. Just as the feather cannot function as an organ of flight until the hooks and barbules are coadapted to fit together perfectly, so the avian lung cannot function as an organ of respiration until the parabronchi system which permeates it and the air sac system which guarantees the parabronchi their air supply are both highly developed and able to function together in a perfectly integrated manner. 8

In short, the transition from mammal lung to avian lung is impossible due to the fact that the lung that would be in a transitional developmental stage would have no functionality. No creature without lungs can live for even a few minutes. Therefore, the creature simply would not have millions of years to wait for random mutations to save its life.

The unique structure of the avian lung demonstrates the presence of a perfect design that supplies the high levels of oxygen required for flight. It only takes a little bit of a common sense to see that the unparalleled anatomy of birds is not an arbitrary result of unconscious mutations. It is clear that the lungs of a bird are another of the countless evidences that all creatures have been created by God.

3-The System of Balance

God has created birds without flaw just as He has the rest of the creation. This fact is manifest in every detail. The bodies of birds have been created to a special design that removes any possible imbalance in flight. The bird's head has been deliberately created light in weight so that the animal does not lean forward during flight: on average, a bird's head weight is about 1% of its body weight.

The aerodynamic structure of the feathers is another property of the system of balance in birds. The feathers, especially in the wing and tail, provide a very effective system of balance for the bird.

These features ensure that a falcon maintains absolute balance while diving for its prey at a speed of 240 mph (384 km/h).

4- The Power and Energy Problem

Every process in the form of a sequence of events, i.e. in biology, chemistry or physics, conforms to the "Principle of the Conservation of Energy". In short, one can summarise this as "it takes a certain amount of energy to get a certain work done".

A significant example of this conservation can be observed in flight of birds. Migrating birds have to store enough energy to take them through their trip. On the other hand, another necessity in flight is being as light as possible. No matter what the results, extra weight has to be done away with. In the meantime, the fuel has also to be as efficient as possible. In other words, while the weight of fuel has to be at a minimum, the energy output from it has to be at a maximum. All of these problems have been solved for birds.

The first step is to determine the optimum speed for flight. If the bird is to fly very slowly, then a lot of energy has to be spent to remain aloft in the air. If the bird is to fly very fast, then fuel will be spent in overcoming air resistance. It is therefore obvious that an ideal speed has to be maintained in order to spend the least amount of fuel. Depending on the aerodynamic structure of the skeleton and wings, a different speed is ideal for each kind of bird.

5. Digestion System
birds digestion systme
The sparrow's heart beats 460 times per minute. Its body temperature is 108°F (42°C). Such a high body temperature, which would mean certain death for a land creature, is vitally important for a bird's survival. The high level of energy birds require for flight is generated by this rapid metabolism.

Flight requires a great deal of power. For this reason birds have the largest muscle-tissue/body-mass ratio of all creatures. Their metabolism is also in tune with high levels of muscle power. On average, a creature's metabolism doubles as the body temperature increases by 50°F (10°C). The sparrow's 108°F (42°C) body temperature and a fieldfare's 109.4°F (43.5°C)body temperature indicate how quickly their metabolism functions. Such a high body temperature, which would kill a land creature, is vitally important for a bird's survival by increasing energy consumption and, therefore, power.

Due to their need for a lot of energy, birds also have a body that digests the food they eat in an optimum fashion. Birds' digestive systems enable them to make the best use of the food they eat. For example, a baby stork puts on 2.2 lbs (1 kg) body mass for every 6.6 lbs (3 kg) food. In mammals with similar food choices, this ratio is about 2.2 lbs (1 kg) to 22 lbs. (10 kg). The circulatory system of birds has also been created in harmony with their high energy requirements. While a human's heart beats 78 times a minute, this rate is 460 for a sparrow and 615 for a humming bird. Similarly, blood circulation in birds is very fast. The oxygen that supplies all of these fast working systems is provided by special avian lungs.

Birds also use their energy very efficiently. They demonstrate significantly higher efficiency in energy consumption than do mammals. For instance, a migrating swallow burns four kilocalories per mile (2.5 per kilometre) whereas a small mammal would burn 41 kilocalories.

Mutation cannot explain the differences between birds and mammals. Even if we assume one of these features to occur through random mutation, which is not a possibility, a single feature by itself does not make any sense. The formation of a high energy-producing metabolism has no meaning without specialised avian lungs.

Moreover, this would cause the animal to choke from insufficient oxygen intake. If the respiratory system were to mutate before the other systems then the creature would inhale more oxygen than it needs, and would be harmed just the same. Another impossibility relates to the skeletal structure: even if the bird somehow obtained the avian lungs and metabolic adaptations it still could not fly. No matter how powerful, no land creature can take off from the ground due to its heavy and relatively segmented skeletal structure. The formation of wings also requires a distinct and flawless "design".

All of these facts take us to one result: it is simply impossible to explain the origin of birds through accidental growth or a theory of evolution. Thousands of different species of birds have been created with all their current
physical features in "a moment". In other words, God has created them individually.


1. Engin Korur, "Gözlerin ve Kanatlarin Sirri" (The Secret of the Eyes and Wings), Bilim ve Teknik (Journal of Science and Technology), October 1984, Issue 203, p. 25.
2. Douglas Palmer, "Learning to Fly" (Review of “The Origin of and Evolution of Birds” by Alan Feduccia, Yale University Press, 1996), New Scientist, Vol. 153, March, 1 1997, p. 44
3. A. Feduccia, The Origin and Evolution of Birds, New Haven, CT: Yale University Press, 1996, p. 130 cited in Jonathan D. Sarfati, Refuting Evolution.
4. Francis Darwin, The Life and Letters of Charles Darwin, Volume II, From Charles Darwin to Asa Gray, April 3rd, 1860
5. Hakan Durmus, "Bir Tüyün Gelismesi" (The Development of a Feather), Bilim ve Teknik (Journal of Science and Technology), November 1991, p. 34.
6. Hakan Durmus, "Bir Tüyün Gelismesi" (The Development of a Feather), Bilim ve Teknik (Journal of Science and Technology), November 1991, page 34-35.
7. Michael Denton, Evolution: A Theory in Crisis, London, Burnett Books Limited, 1985, p. 210-211.
8. Michael Denton, Evolution: A Theory in Crisis, London, Burnett Books Limited, 1985, p. 211-212.

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