CHAPTER 3

Communication and Target Location Systems

ECHOLOCATION OF BATS

Bats are very interesting creatures. The most intriguing of their abilities is their extraordinary faculty of navigation.

The echolocative ability of bats was discovered through a series of experiments conducted by scientists. Let us take a closer look at these experiments in order to unveil the extraordinary design of these creatures:26

In the first of these experiments, a bat was left in a completely dark room. On one corner of the same room, a fly was placed as a prey for the bat. From then on, everything taking place in the room was monitored with night vision cameras. As the fly started to take into the air, the bat, from the other corner of the room, swiftly moved directly to where the fly was and captured it. Through this experiment, it was concluded that the bats had a very sharp sense of perception even in complete darkness. However, was this perception of the bat due to the sense of hearing? Or, was it because it had night vision?

In order to answer these questions, a second experiment was carried out. In a corner of the same room a group of caterpillars were placed and covered under a sheet of newspaper. Once released, the bat did not lose any time in lifting the newspaper sheet and eating the caterpillars. This proved that the navigational faculty of the bat has no relationship with the sense of vision.

Scientists continued with their experiments on bats: a new experiment was conducted in a long corridor, on one side of which was a bat and on the other a group of butterflies. In addition, a series of partition walls were installed perpendicular to the sidewalls. In each partition, there was a single hole just big enough for the bat to fly through. These holes, however, were located in a different spot on each partition. That is, the bat had to zigzag its way through them.

Experiments show that bats are able to easily locate and fly through the passageways in the walls even in complete darkness.

Scientist started their observations as soon as the bat was released into the pitch darkness of the corridor. When the bat came to the first

partition it located the hole easily and passed right through it. The same was observed at all partitions: the bat appeared not only to know where the partition was but also where exactly the hole was. After going through the last hole, the bat filled its stomach with its catch.

Absolutely stunned by what they observed, the scientists decided to conduct one last experiment in order to understand the sensitivity of the bat's perception. The goal this time was to determine the bat's perceptual limits more clearly. Again, a long tunnel was prepared and steel wires of 3/128-inch (0.6 mm) diametre were hung from ceiling to floor and placed randomly throughout. Much to the observers' astonishment, the bat completed its journey without tripping over a single obstacle. This flight showed that the bat is able to detect obstacles of as little as 3/128-inch (0.6 mm) thickness. The research that followed revealed that the bat's incredible perceptual faculty is linked to their echolocation system. Bats radiate high frequency sounds in order to detect objects around them. The reflection of these sounds, which are inaudible to humans, enables the bat to get a "map" of its environment.27 That is, the bat's perception of a fly is made possible by the sounds reflected back to the bat from the fly. An echolocating bat registers each outgoing sound pulse and compares the originals to returning echoes. The time lapsed between generating the outgoing sound and receiving an incoming echo provides an accurate assessment of a target's distance from the bat. For example, in the experiment where the bat caught the caterpillar on the floor, the bat perceived the caterpillar and the shape of the room by emitting high pitch sounds and detecting the reflected signals. The floor reflected the sounds; hence, the bat determined its distance from the floor. On the contrary, the caterpillar was about 3/16-inch (0.5 cm) to 3/8-inch (1 cm) closer to the bat than was the ground. In addition, it made minute moves and this, in turn, changed the reflected frequencies. This way, a bat could detect the presence of a caterpillar on the floor. It emitted about twenty thousand cycles in a second and could analyse all the reflected sounds. Furthermore, while it carried out this task, the bat itself travelled. Careful consideration of all these facts clearly reveals the miraculous design in their creation.

The system used by bats to locate their prey is millions of times more efficient and accurate than manmade radar and sonar. The table above clearly illustrates these properties. "Echolocation efficiency index" is range divided by the product weight times power times target diametre. "Relative figure of merit" compares the echolocation efficiency indexes with the bat as 1.

Another stunning feature of bats' echolocation is the fact that the hearing of bats has been created such that they cannot hear any other sounds than their own. The spectrum of frequencies audible to these creatures is very narrow, which would normally create a great problem for the animal because of the Doppler Effect. According to the Doppler Effect, if the source of sounds and the receiver of sounds are both relatively stationary, the receiver will detect the same frequency as the source emits. However, if one or the other is moving, the detected frequency will be different than the emitted frequency. In this case, the frequency of the reflected sound could fall into the spectrum of frequencies inaudible to the bat. The bat, therefore, faces the potential problem of not being able to hear the echoes of its sounds from a fly that moves away.

The largest bat colony on earth, with a population reaching 50 million, lives in America. Freetails ride 60 mph (95 km/h), and fly as high as 10,000 feet (3050 metres). It is so large that it can be easily observed by airport radar.28	It is discovered that bats wander in many different ways once they leave their cave. However, they always fly back to it on a straight route from wherever they are. It is still not clear how they are able to navigate the return journey to the cave.

Nevertheless, this is never a problem for the bat because it adjusts the frequency of sounds that it sends towards moving objects as if it knows about the Doppler Effect. For instance, it sends the highest frequency sounds to a fly moving away so that the reflections are not lost in the inaudible section of the sound spectrum.

So, how does this adjustment take place?

In the brain of the bat, there are two kinds of neurons (nerve cells) that control its sonar systems; one perceives the reflected ultrasound and the other commands the muscles to produce echolocation calls. These two neurons work in such complete synchrony that a minute deviation in the reflected signals alerts the latter and provide the frequency of the call to be in tune with the frequency of the echo. Hence, the pitch of the bat's ultrasound changes in accordance with its surroundings for maximum efficiency.

It is impossible to overlook the blow that this system deals to the explanations of the theory of evolution through coincidence. The sonar system of bats is extremely complex in nature and cannot be explained by evolution through arbitrary mutations. The simultaneous existence of all components of the system is vital for its functionality. The bat has not only to release high pitch sounds but also to process reflected signals and to manoeuvre and adjust its sonar squeals all at the same time. Naturally, all of this cannot be explained by coincidence and can only be a sure sign of how flawlessly Allah created the bat.

Scientific research further reveals new examples of the miracles of creation in bats. Through each new miraculous discovery, the world of science attempts to understand how these systems work. For example, new research on bats has had very interesting findings in recent years.29 A few scientists, who wanted to examine a group of bats living in a certain cave, installed transmitters on some of the group members. Bats were observed to leave the cave at night and feed outside until dawn. Researchers kept detailed records of these journeys. They discovered that some bats travelled as far as 30-45 miles (50-70 kilometres) from the cave. The most astonishing finding was the return flight, which started shortly before sunrise. All bats flew straight back to the cave from wherever they were. How can bats know where they are and how far away they are from their caves?

We do not yet have detailed knowledge of how they navigate their return flight. Scientists do not believe the auditory system to have a big impact on the return journey. Reminding us that bats are completely blind to light, scientists expect to encounter another surprising system. In short, science continues to discover new miracles of creation in the bats.

ELECTRIC FISH

The Electroshock Gun in the Electric Eel

The electric eels, whose lengths sometimes exceed 6.6 feet (2 metres), live in the Amazon. Two-thirds of the bodies of these fish are covered with electrical organs, which have around 5,000 to 6,000 electroplaques. Thus, they can produce charges of 500 volts of electricity at about two amperes. This is roughly equivalent to more power than a conventional TV set utilises.

The faculty of generation of electricity has been given to these creatures for purposes both of defence and offence. The fish uses this electricity to kill its predators by giving them an electric shock. The electric shock generated by this fish is enough to kill cattle from a distance of 6.6 feet (2 metres). The electricity-generating mechanism of this fish is capable of engaging as quickly as in two to three thousandth of a second.

Such an immense power in a creature is a tremendous miracle of creation in itself. The system is quite complex and cannot possibly be explained through "step by step" development. That is because an electrical system without full functionality could not bring the creature any advantage in terms of survival. In other words, all components of the system must have been created perfectly at the same time.

Fish that "See" By Means of an Electrical Field

Apart from fish armoured with potential electric charges, there are other fish that generate low voltage signals of two to three volts. If these fish do not use such weak signals for hunting or defence, for what could they be possibly used?

Fish utilise these weak signals as a sensory organ. Allah created a sensory system in the bodies of fish, which transmits and receives these signals.30

The fish produces emissions of electricity in a specialised organ on its tail. The electricity is emitted from thousands of pores on the creature's back in the form of signals that momentarily create an electrical force field surrounding it. Any object within this field refracts it, by which the fish is informed of the size, conductivity and movement of the object. On the body of fish, there are electrical sensors that continuously detect the field just as do radar.

In short, these fish have a radar that transmits electrical signals and interprets the alterations in the fields caused by objects interrupting these signals around their bodies. When the complexity of radar used by humans is considered, the wonderful creation in the body of fish becomes clear.

Special Purpose Receptors

Gnathonemus Petersi

In the bodies of these fish, there are various types of receptors. Ampullary receptors detect the low frequency electrical signals given off by other swimming fish or insect larvae. These receptors are so sensitive that they can even detect the magnetic field of the earth as well as gather information on prey and predators.

The ampullary receptors cannot perceive the high frequency signals transmitted by the fish. This is accomplished by a tubular receptors. These sensors are sensitive to fish's own discharge and they work to map the surroundings.

By means of this system these fish can communicate and warn one another against any threats. They also exchange information about species, age, size and gender.

Signals Describing Gender Differences

Each species of electric fish has a unique signature signal. Furthermore, there can be differences among the individuals of a species. However, the general structure remains unchanged. Some details are particular to the individual. When a female runs across a male fish it immediately senses it and behaves accordingly.

Signals Describing Age

Electrical signals also carry information on the age of these fish. A newly hatched fish bears a different signature from an adult. The signals of the newly hatched fish maintain their characteristic until the fourteenth day after its birth, when they change and become like the normal signals of an adult. This plays a great role in regulating the complex relationships of motherhood and fatherhood. A father can recognise his infant, and bring it home to safety.

Living Activities Communicated Through Signals

Fish can also communicate information other than gender and age. In all the species of electrical fish, frequency hikes transmit alerting messages. For instance, an elephant fish (Mormyridae) normally transmits electrical signals with a frequency of 10 Hz. i.e.10 vibrations per second, which it can easily increase up to 100-120 Hz. A motionless elephant fish warns opponents of an attack. This behaviour resembles the tightening of fists before a fight. Most of the time, this warning is powerful enough to discourage the opponent. After a fight, the wounded party, in an electrical silence, stops sending signals for about 30 minutes. The fish that calms down or leaves the fight usually remains motionless. The purpose behind this is to make it harder for the others to find them. Another purpose is to avoid hitting surrounding objects since they become electrically blind due to lack of signals.

An electric fish locates another one by means of signals.

Special System for Non-Confusion of Signals

So then, what happens when an electric fish comes near another producing the same signals? Does this not interfere with both their radars? Interference would be a normal consequence here. However, they have been created with a natural defence mechanism that prevents this confusion.

Experts name this system "Jamming Avoidance Response" or JAR for short. When the fish encounters another at the same frequency, it changes its frequency. This way confusion is avoided early and it, therefore, never reaches any further.

All of this confirms the extremely complex systems in electrical fish. The origin of these systems cannot be fully explained by evolution. Likewise, Darwin in his book, The Origin of Species, admitted the impossibility of explaining these creatures by his theory in a chapter called "Difficulties of the Theory".31 Since Darwin, the electrical fish have been shown to have much more complex systems than he thought.

Just like all other forms of life, electric fish were also created flawlessly by Allah as a demonstration for us of the existence and infinite knowledge of Allah Who created them.

Types of signals emitted by different species of fish
The fish that transmit electrical waves communicate through these waves. Members of the same species use similar signals. Due to their communal life, they change frequencies in order to prevent confusion, which enables similar but distinct signals to be distinguished.	An electric fish can detect the gender of another by means of signals.

SONAR INSIDE A DOLPHIN'S SKULL

A dolphin can distinguish between two different metal coins under water in complete darkness and up to 2 miles (3 kilometres) away. Does it see that far? No, it does this without seeing. It can make such accurate determinations by means of the perfect design of an echolocation system inside its skull. It gathers very detailed information on shape, size, speed and structure of near objects.

It takes some time for a dolphin to master the skills needed to use such a complicated system. While an experienced adult dolphin can detect most objects through a few signals, a juvenile has to experiment for years.

Dolphins do not use their echolocation just to detect their surroundings. Sometimes they group during feeding and emit high-pitched sounds so powerful that they dazzle their prey, which are then ready to be picked up. An adult dolphin produces sounds inaudible to humans (20,000 Hz. and above). The focusing of soundwaves is done in several areas of the dolphin's head. The melon, which is a fatty structure in the dolphin's forehead, serves as an accaustical lens and focuses the clicks of the dolphin into a narrow beam. Therefore, the dolphin can direct the clicks at will by moving its head. It can direct these waves at will by moving its head.

The clicks immediately echo back when they hit any obstacle. The lower jaw acts as a receptor, which transmits the signals back to the ear. On each side of the lower jaw is a thin bony area, which is in contact with a lipid material. Sound is conducted through this lipid material to the auditory bullae, a large vesicle. Then the ear forwards the data to the brain, which analyses and interprets the meanings. A similar lipid material also exists in the sonar of whales. Different lipids (fatty compounds) bend the ultrasonic (sound waves above our range of hearing) sound waves traveling through them in different ways. The different lipids have to be arranged in the right shape and sequence in order to focus the returning sound waves. Each separate lipid is unique and different from normal blubber lipids and is made by a complicated chemical process that requires a number of different enzymes. This sonar system in dolphins could not possibly have developed gradually, as claimed by the theory of evolution. That is because only by the time the lipids would have evolved to their final place and shape, could the creature have made use of this crucial system. In addition, support systems like the lower jaw, the inner ear system and the analysis centre in the brain would all have to be fully developed. Echolocation clearly is an "irreducibly complex" system, which for it to have evolved in phases is simply impossible. Hence, it is obvious that the system is another flawless creation of Allah.

An adult dolphin radiates sounds inaudible to humans (20,000 Hz. and above). These waves are released from the lobe, called "melon", in front of their heads. It can direct these waves at will by moving its head. The sonar waves are immediately reflected when they encounter any obstacle. Lower jaw acts as a receptor, which transmits the signals back to the ear. Ear forwards the data to the brain, which analyzes and interprets the meanings.

THE STORY OF A MOMENT'S COMMUNICATION

Everybody can remember a time when his or her eyes met with an acquaintance's eyes and they greeted one another. Would you believe that this communication of a brief moment has a long story?

Let's assume that on a certain afternoon two men are situated apart from one another. In spite of their close friendship, they have not yet recognised one another. One of these men, turning his head in the direction of his friend, whom he has not yet recognised, starts a chain of biochemical reactions: the light reflected from the body of his friend enters the eye lens at a speed of ten trillion photons (light particles) per second. Light travels through the lens and the fluid that fills the eyeball before falling on the retina. On the retina there are about hundred million cells called "cones" and "rods". Rods differentiate light from dark and cones perceive colours.

CORNEA AND IRIS The cornea, one of the 40 basic components of the eye, is a transparent layer located at the very front of the eye. It allows light through as perfectly as does window glass. It is surely not a coincidence that this tissue, found at nowhere else in the body, is situated just at the right place, that is, the front surface of the eye. Another important component of the eye is the iris, which gives the eye its colour. Located right behind the cornea, it regulates the amount of light admitted into the eye by contracting or expanding the pupil - the circular opening in the middle. In bright light, it immediately contracts. In dim light, it enlarges to allow more light to enter the eye. A similar system has been adapted as a basis for the design of cameras in order to adjust the amount of light intake, but it is nowhere near as successful as the eye.

The human eye functions through the harmonious working of about forty different components. In the absence of even one of these components would make the eye useless. For instance, in the absence of even tear gland alone, the eye would eventually dry out and cease to function. This system, which is irreducible to simplicity, can never be explained by "gradual development" as is claimed by evolutionists. This shows that the eye emerged in a complete and perfect form, which means that it was created.

Depending on the external objects, varying light waves fall on different places on the retina. Let's think about the moment the person in our assumed situation sees his friend. Some features on his friend's face cast different intensities of light on his retina e.g. darker facial features such as eyebrows would reflect light at much lower intensities. Neighbouring cells on the retina, however, receive stronger intensities of light reflected from the forehead of his friend. All of his friend's facial features cast waves of various intensities on the retina of his eye.

What kind of stimuli do these light waves provoke?

The answer to this question is, indeed, very complicated. Nevertheless, the answer has to be examined to fully appreciate the extraordinary design of the eye.

The Chemistry of Seeing

When photons hit the cells of the retina, they activate a chain reaction, rather like a domino effect. The first of these domino pieces is a molecule called "11-cis-retinal" that is sensitive to photons. When struck by a photon, this molecule changes shape, which in turn changes the shape of a protein called "rhodopsin" to which it is tightly bound. Rhodopsin then takes a form that enables it to stick to another resident protein in the cell called "transducin".

Prior to reacting with rhodopsin, tranducin is bound to another molecule called GDP. When it connects with rhodopsin, transducin releases the GDP molecule and is linked to a new molecule called GTP. That is why the complex consisting of the two proteins (rhodopsin and transducin) and a smaller chemical molecule (GTP) is called "GTP-transducinrhodopsin".

The new GTP-transducinrhodopsin complex can now very quickly bind to another protein resident in the cell called "phosphodiesterase". This enables the phosphodiesterase protein to cut yet another molecule resident in the cell, called cGMP. Since this process takes place in the millions of proteins in the cell, the cGMP concentration is suddenly reduced.

How does all this help with sight? The last element of this chain reaction supplies the answer. The fall in the cGMP amount affects the ion channels in the cell. The so-called ion channel is a structure composed of proteins that regulate the number of sodium ions within the cell. Under normal conditions, the ion channel allows sodium ions to flow into the cell, while another molecule disposes of the excess ions to maintain a balance. When the number of cGMP molecules falls, so does the number of sodium ions. This leads to an imbalance of charge across the membrane, which stimulates the nerve cells connected to these cells, forming what we refer to as an "electrical impulse". Nerves carry the impulses to the brain and "seeing" happens there.

In brief, a single photon hits a single cell and, through a series of chain reactions, the cell produces an electrical impulse. This stimulus is modulated by the energy of the photon, that is, the brightness of light. Another fascinating fact is that all of the processes described so far happen in no more than one thousandth of a second. Other specialised proteins within the cells convert elements such as 11-cis-retinal, rhodopsin and transducin back to their original states. The eye is under a constant shower of photons, and the chain reactions within the eye's sensitive cells enable it to percieve each one of these photons.32

The process of sight is actually a great deal more complicated than the outline presented here would indicate. However, even this brief overview is sufficient to demonstrate the extraordinary nature of the system. There is such a complicated, finely calculated design inside the eye that chemical reactions in the eye resemble the domino shows in the Guinness Book of World Records. In these shows, tens of thousands of domino pieces are so strategically placed that tipping the first piece activates the entire system. In some areas of the domino chain, many apparatuses are installed to start a new sequences of reactions, e.g. a winch carrying a piece to another location and dropping it exactly at the place necessary for a further sequence of reactions.

Of course, nobody thinks that these pieces have been "coincidentally" brought to their precise locations by winds, quakes or floods. It is obvious to everyone that each piece has been placed with great attention and precision. The chain reaction in the human eye reminds us that it is nonsense to even entertain the thought of the word "coincidence". The system is composed of a number of different pieces assembled together in very delicate balances and is a clear sign of "design". The eye is created flawlessly.

Click image to see larger photo The figure above illustrates the biochemistry of vision. Symbols indicate; RH=Rhodopsin, Rhk=Rhodopsin Kinase, A=Ariestin, GC=Guanylate Cyclase, T=Tranducin, PDE=Phosphodiesterase.

Biochemist Michael Behe comments on the chemistry of the eye and the theory of evolution in his book Darwin's Black Box:

Now that the black box of vision has been opened, it is no longer enough for an evolutionary explanation of that power to consider only the anatomical structures of whole eyes, as Darwin did in the nineteenth century (and as popularizers of evolution continue to do today). Each of the anatomical steps and structures that Darwin thought were so simple actually involves staggeringly complicated biochemical processes that can not be papered over with rhetoric.33

Beyond Seeing

What has been explained so far is the first contact of photons, reflected off a friend's body, with a man's eye. The retinal cells produce electrical signals through complicated chemical processes as described above. In these signals there exists such detail that the face of the man's friend in the example, his body, hair colour and even a minute mark on his face have been encoded. Now the signal has to be carried to the brain.

Nerve cells (neurons) stimulated by retinal molecules show a chemical reaction as well. When a neuron is stimulated, protein molecules on its surface change shape. This blocks the movement of the positively charged sodium atoms. The change in the movement of the electrically charged atoms creates a voltage differential within the cell, which results in an electrical signal. The signal arrives at the tip of the nerve cell after travelling a distance shorter than a centimetre. However, there is a gap between two nerve cells and the electrical signal has to cross this gap, which presents a problem. Certain special chemicals between the two neurons carry the signal. The message is carried this way for about a quarter to a fortieth of a millimetre. The electrical impulse is conducted from one nerve cell to the next until it reaches the brain.

These special signals are taken to the visual cortex in the brain. The visual cortex is composed of many regions, one on top of the other, about 1/10 inch (2.5 mm) in thickness and 145 square feet (13.5 square metres) in area. Each one of these regions includes about seventeen million neurons. The 4th region receives the incoming signal first. After a preliminary analysis, it forwards the data to neurons in other regions. In any phase, any neuron can receive a signal from any other neuron.

This way, the man's picture forms in the visual cortex of the brain. However, the image now needs to be compared to the memory cells, which is also done very smoothly. Not a single detail is overlooked. Furthermore, if the friend's perceived face looks slightly more pale than normal then the brain activates the thought, "why is my friend's face so pale today?"

Greeting

That's how two separate miracles happen within a period of time less than a second, which we refer to as "seeing" and "recognising".

The input that arrives in hundreds of millions of light particles reaches the mind of the person, is processed, compared to the memory and enables the man to recognise his friend.

A greeting follows recognition. A person deduces the reaction to be given to acquaintances from within the memory cells in less than a second. For example, he determines that he needs to say "greetings" upon which the brain cells controlling facial muscles will command the move that we know as a "smile". This command is similarly transferred through nerve cells and triggers a series of other complicated processes.

Simultaneously, another command is given to the vocal cords in the throat, tongue and the lower jaw and the "greetings" sound is produced by the muscle movements. Upon release of the sound, air molecules start travelling towards the man to whom the greeting is sent. The auricle gathers these sound waves, which travel at approximately twenty feet (six metres) per one fiftieth of a second.

The auricle is designed to collect and focus sounds into the auditory canal. The inside surface of the auditory canal is covered with cells and hairs that secrete a thicle waxy product to protect the ear against external dirt. At the end of the ear canal towards the start of the middle ear is the eardrum. Beyond the eardrum there are three small bones called the hammer, anvil and stirrup. The eustachian tube functions to balance air pressure in the middle ear. At the end of the middle ear is the cochlea that has an extremely sensitive hearing mechanism and is filled with a special fluid.

The vibrating air inside both ears of that person rapidly travels to his middle ear. The eardrum, 0.30 inch (7.6 millimetre) in diametre, starts vibrating as well. This vibration is then transferred to the three bones in the middle ear, where they are converted into mechanical vibrations that travel to the inner ear. They then create waves in a special fluid inside a snail shell-like structure called the cochlea.

Inside the cochlea, various tones of sound are distinguished. There are many strings of varying thickness inside the cochlea just as in the musical instrument, the harp. The sounds of the man's friend literally play their harmonies on this harp. The sound of "greetings" starts from a low pitch and rises. First, the thicker cords are rattled and then the thinner ones. Finally, tens of thousands of little bar-shaped objects transfer their vibrations to the auditory nerve.

Now the sound "greetings" becomes an electrical signal, which quickly travels to the brain through the auditory nerves. This journey inside the nerves continues until reaching the hearing centre in the brain. As a result, in the person's brain, the majority of the trillions of neurons become busy evaluating the visual and audio data gathered. This way, the person receives and perceives his friend's greeting. Now he returns the greeting. The act of speaking is realised through perfect synchronisation of hundreds of muscles within a minute portion of a second: the thought that is designed in the brain as a response is formulated into language. The brain's language centre, known as Broca's area, sends signals to all the muscles involved.

THE TRAVELLING OF THE SOUND FROM EAR TO BRAIN It is He Who has created hearing, sight and hearts for you. What little thanks you show! (Surat al-Muminun: 78) The ear is such a complex wonder of design that it alone nullifies the explanations of the theory of evolution in regards to a creation based on "coincidence". The hearing process in the ear is made possible by a completely irreducibly complex system. Sound waves are first collected by the auricle (1) and then hit the eardrum (2). This sets the bones in the middle ear (3) vibrating. Thus sound waves are translated into mechanical vibrations, which vibrate the so-called "oval window" (4), which in turn sets the fluid inside the cochlea (5) in motion. Here, the mechanical vibrations are transformed into nerve impulses which travel to the brain through the vestibular nerves (6). There is an extremely complex mechanism inside the cochlea. The cochlea (enlarged figure in the middle) has some canals (7), which are filled with fluid. The cochlear canal (8) contains the "organ of corti" (9) (enlarged figure on far right), which is the sense organ of hearing. This organ is composed of "hair cells" (10). The vibrations in the fluid of the cochlea are transmitted to these cells through the basilar membrane (11), on which the organ of corti is situated. There are two types of hair cells, inner hair cells (12a)and outer hair cells (12b). Depending on the frequencies of the incoming sound, these hair cells vibrate differently which makes it possible for us to distinguish the different sounds we hear. Outer hair cells (13) convert detected sound vibrations into electrical impulses and conduct them to the vestibular nerve (14). Then the information from both ears meet in the superior olivary complex (15). The organs involved in the auditory pathway are as follows: Inferior colliculus (16), medial geniculate body (17), and finally the auditory cortex (18).34 The blue line inside the brain shows the route for high pitches and the red for low pitches. Both cochleas in our ears send signals to both hemispheres of the brain. As is clear, the system enabling us to hear is comprised of different structures that have been carefully designed in the minutest detail. This system could not have come into existence "step by step", because the lack of the smallest detail would render the entire system useless. It is, therefore, very obvious that the ear is another example of flawless creation.

First, the lung provides "hot air". Hot air is the raw material of speech. The primary function of this mechanism is the inhalation of oxygen-rich air into the lungs. Air is taken in through the nose, and it travels down the trachea into the lungs. The oxygen in the air is absorbed by the blood in the lungs. The waste matter of blood, carbon dioxide, is given out. The air, at this point, becomes ready to leave the lungs.

The air returning from the lungs passes through the vocal cords in the throat. These cords are like tiny curtains, which can be "drawn" by the action of the small cartilages to which they are attached. Before speech, the vocal cords are in an open position. During speech they are brought together and caused to vibrate by the exhaled air passing through them. This determines the pitch of an individual's voice: the tenser the cords, the higher the pitch.

The air is vocalised by passing through the cords and reaches to the surface via the nose and mouth. The person's mouth and nose structure adds personal properties unique to him. The tongue draws near to and away from the palate and the lips take various shapes. Throughout these processes, many muscles work at great speed.35

The person's friend compares the sound he hears to others in his memory. By comparing, he can immediately tell if it is a familiar sound. Therefore, both parties recognise and greet each other.

The three bones in the middle ear function as a bridge between the eardrum and the inner ear. These bones, which are connected to one another by joints, amplify sound waves, which are then transmitted to the inner ear. The pressure wave that is created by the contact of the stirrup with the membrane of the oval window travels inside the fluid of the cochlea. The sensors triggered by the fluid start the "hearing" process.

All the above takes place during two friends noticing and greeting one another. All of these extraordinary processes happen at incredible speeds with stunning precision, of which we are not even aware. We see, hear and speak so very easily as if it is a very simple thing. However, the systems and processes that make them possible are so unimaginably complex.

In order to facilitate speech, not only do the vocal cords, nose, lungs and air passages have to work in harmony, but also the muscle systems that support these organs. Sounds created during speech are produced by air passing through the vocal cords.	Vocal cords are comprised of flexible cartilages tied to muscles on the skeleton. When the muscles are at rest, the cords are open (left). The cords close during speech (below). The tenser the cords, the higher the pitch.

The operation of the vocal cords has been photographed by means of high-speed cameras. All of the different positions seen above take place within less than one tenth of a second. Our speech is made possible through the flawless design of the vocal cords.

This complex system is full of examples of unparalleled design that the theory of evolution cannot explain. The origins of vision, hearing and thinking cannot be explained by the trust of evolutionists in "coincidences". On the contrary, it is obvious that all of them have been created and given to us by our Creator. While the human cannot even understand the working mechanism of systems that enable him to see, hear and think, the infinite wisdom and power of Allah Who created all these from nothing is apparently obvious.

In Qur'an, Allah invites humans to ponder this and to be thankful:

Allah brought you out of your mothers' wombs knowing nothing at all, and gave you hearing, sight and hearts so that perhaps you would show thanks. (Surat an-Nahl: 78)