The Human Ear: Masterpiece of Engineering
The study of the human being has long been a fascinating task for philosophers, physicians and poets. With the recent advances in science and technology our knowledge about ourselves is increasing rapidly.
Humans are the only creatures that can stand upright naturally and have large complex brains that they can use to synthesize sounds into speech. No other creature has this capability. The human ear is unique since, besides processing sounds, it is also the organ of balance and equilibrium. Our ability to stand upright and walk on two legs has brought many advantages – specifically the opportunity to develop manual skills such as reading, writing, driving and operating equipment.
Without our eyes and ears and the ability to stand up, even the most modern communication systems will not work, since the eyes and ears have to prepare the input and interpret the output.
Why was the human being endowed with these attributes? Since we are the most intelligent species and dominate this earth, it behooves us to reflect on this.
Each part of the human is uniquely and beautifully constructed in the most efficient design. Today, we will look at the amazing human ears and see how clearly their construction points to a designer.
PLAIN BUT PERFECT!
Human ears are not much to look at, yet behind these flaps of skin and cartilage lie structures of such delicacy that they shame the most skillful craftsman, and of such reliable automatic operation that they inspire awe in the most ingenious engineer. Working together, the structure of the outer, middle, and inner ear perform acts of amazing range and virtuosity.
The ear has three main parts: the outer, middle, and inner ear.
The outer ear (all that we normally see) comprises the pinna, i.e., the flap of skin and cartilage leading to a narrow tunnel that terminates in the eardrum. The middle ear is an air filled cavity with the eardrum on one side and piece of stretched skin known as the oval window on the other side, leading to the inner ear, which contains the organs of hearing and the organ of balance.
The reason we have two ears is because they form a stereo system allowing us to identify the place from which the sound originated and also to identify whether the source is moving. The processing of sound by the ear and brain is so accurate that clicks presented to one ear and then the other can be distinguished as separate sounds when the time interval between them is as small as thirty microseconds.
YOU COULD HEAR A PINDROP…
The virtuosity of the human hearing is as remarkable as its importance. A man can hear a mosquito buzzing outside the window even though the power of the sound reaching him is no more than one quadrhhonth of a watt. If 100 such buzzes (100,000,000,000,000,000) could be combined and converted into electricity, there would be just enough power to light one reading lamp!
The sensitivity of the ear is remarkable. The movement of the eardrum in response to the minimum audible sound at a frequency of 1000 Hz is about a thousand millionth of a centimeter: considerably less than the diameter of a hydrogen atom. The movement of the basilar membrane in response to the same sound is about a hundred times smaller – about the diameter of an atomic nucleus!
This represents the ultimate limit of performance. If the, sensitivity of the ear was further increased, we would be conscious of the continual bombardment of the eardrum by air molecules. Even at the present limit it is surprising that we do not hear our own blood flowing through the tiny vessels in the eardrum. This is so because the ear can ignore signals which are constantly present.
MUSICIANS – ALL
The ear also displays a judgement of pitch which is unequalled in the animal kingdom, and makes man the most musical of all living animals. With no musical training, we can distinguish the Note A sounded on the piano from the same note played on a violin. We can also distinguish the combination of different tones peculiar to each instrument that make up the note. We can reject the hubbub of a function while picking out a single familiar voice. Even during sleep the ear continues to function with incredible efficiency: because the brain can interpret and select signals passed to it by the ear, a person can sleep soundly through noisy traffic and the blaring of a neighbor’s television , and yet awaken promptly at the gentle urging of an alarm clock. A barking dog, a squealing tire, a footstep — can all be identified. In fact, a normal ear can discriminate among some 400,000 sounds.
ALL THIS AND MORE!
The ears, besides being a high fidelity stereophonic hearing system, are also responsible for keeping the body in balance. This is done with the help of two systems located within the inner ear.
Of all the organs of the body, few can accomplish as much in so little a space as the ear. If an engineer could duplicate its functions, he would have to compress into approximately one cubic inch a sound system tht includes an impedance matcher, a wide range mechanical analyser, a mobile relay and amplification unit, a multichannel transducer to convert mechanical energy to electrical energy, a system to maintain a delicate hydraulic balance and an internal two-way communication system. Even if he could perform this miracle of miniaturization, he would be unable to match the ear’s performance.
Many birds and animals have learned to signal one another by their voices, both for warning and recognition, but we, the humans, with our ears, our mobile tongues and throats, and our large complex brains have learned to speak. We have learned to be articulate, to attach arbitrary and abstract meaning to sounds, synthesize words, and create a language which we then use as a tool to communicate our experiences of the past and also our ideas and plans for future action. We now have innumerable languages across the world. Humans are the only creatures capable of achieving all this. The great strides we are making in every field are evidence of this fact. Even with our minimal numbers and our average sizes we dominate the planet earth to the exclusion of all other creatures.
WHY ALL THIS?
Is there a lesson to be learned from all this? Is there a purpose? And if so, what is it? What is our responsibility?
It seems abundantly clear to me that our main responsibility is to use our ears and eyes and brain to recognize the role of the Almighty God and to understand the purpose of our existence.
Using our God given senses and our unique ability to explore this vast Universe we have learnt a great deal about the physical laws that govern it. We know that these laws are fixed and consistent; that they apply equally at all points through out the Universe, without differentiation. This attests to the fact that there is one Creator and His system is unchangeable.
Let us be appreciative of Him by using our senses in the only way they should be used – to recognize Him as the absolute God and pledge our allegiance to Him alone, the Creator of mankind.
He is the One who granted you the hearing, the eyesight and the brains. Rarely are you appreciative. (Quran, 23:78)
By Shakira Karipineni
Source: http://www.universalunity.net/ear.htm
