why are ears shaped the way they are?

Answer 1

to make it easier to catch sound waves..

Answer 2

Why is the cochlea in our ears shaped like a spiral? According to new work by scientists in the US, the spiral shape makes us more sensitive to low frequency sounds.

Catching Sound
We saw in the last section that sound travels through the air as vibrations in air pressure. To hear sound, your ear has to do three basic things:

Direct the sound waves into the hearing part of the ear
Sense the fluctuations in air pressure
Translate these fluctuations into an electrical signal that your brain can understand
The pinna, the outer part of the ear, serves to "catch" the sound waves. Your outer ear is pointed forward and it has a number of curves. This structure helps you determine the direction of a sound. If a sound is coming from behind you or above you, it will bounce off the pinna in a different way than if it is coming from in front of you or below you. This sound reflection alters the pattern of the sound wave. Your brain recognizes distinctive patterns and determines whether the sound is in front of you, behind you, above you or below you.

Your brain determines the horizontal position of a sound by comparing the information coming from your two ears. If the sound is to your left, it will arrive at your left ear a little bit sooner than it arrives at your right ear. It will also be a little bit louder in your left ear than your right ear.

Since the pinnae face forward, you can hear sounds in front of you better than you can hear sounds behind you. Many mammals, such as dogs, have large, movable pinnae that let them focus on sounds from a particular direction. Human pinnae are not so adept at focusing on sound. They lay fairly flat against the head and don't have the necessary muscles for significant movement. But you can easily supplement your natural pinnae by cupping your hands behind your ears.

Drum Set
Once the sound waves travel into the ear canal, they vibrate the tympanic membrane, commonly called the eardrum. The eardrum is a thin, cone-shaped piece of skin, about 10 millimeters (0.4 inches) wide. It is positioned between the ear canal and the middle ear. The middle ear is connected to the throat via the eustachian tube. Since air from the atmosphere flows in from your outer ear as well as your mouth, the air pressure on both sides of the eardrum remains equal. This pressure balance lets your eardrum move freely back and forth

The eardrum is rigid, and very sensitive. Even the slightest air-pressure fluctuations will move it back and forth. It is attached to the tensor tympani muscle, which constantly pulls it inward. This keeps the entire membrane taut so it will vibrate no matter which part of it is hit by a sound wave.


Normal ear anatomy



This tiny flap of skin acts just like the diaphragm in a microphone. The compressions and rarefactions of sound waves push the drum back and forth. Higher-pitch sound waves move the drum more rapidly, and louder sound moves the drum a greater distance.

The eardrum can also serve to protect the inner ear from prolonged exposure to loud, low-pitch noises. When the brain receives a signal that indicates this sort of noise, a reflex occurs at the eardrum. The tensor tympani muscle and the stapedius muscle suddenly contract. This pulls the eardrum and the connected bones in two different directions, so the drum becomes more rigid. When this happens, the ear does not pick up as much noise at the low end of the audible spectrum, so the loud noise is dampened.

In addition to protecting the ear, this reflex helps you concentrate your hearing. It masks loud, low-pitch background noise so you can focus on higher-pitch sounds. Among other things, this helps you carry on a conversation when you're in a very noisy environment, like a rock concert. The reflex also kicks in whenever you start talking -- otherwise, the sound of your own voice would drown out a lot of the other sounds around you.

The eardrum is the entire sensory element in your ear. As we'll see in the coming sections, the rest of the ear serves only to pass along the information gathered at the eardrum.

Answer 3

To enable maximum sound waves to enter the ear.

The ear needs to receive as much information as possible for you to hear a sound.

The shape of the ear works to maximise sound that is then transferred to the brain.

Answer 4

The outer part of the ear collects sound. That's the best shape that can be..

For more information see link.

http://en.wikipedia.org/wiki/Ears

Answer 5

Perhaps the difference. thicknesses (ridges, lobe, etc...) are conducive to different frequencies. The smallest freq. we hear is about 1/2 an inch modulation (cricket chirping) The biggest is about 4 1/2 feet ( Base-boom in expensive car-stereo)

Answer 6

because of two major function
1) To collect the maximum amount of sound ways.
2) Acts as a Radiator or colling system for head & brain.

Answer 7

its the way all the lumps n bumps channel sound in to the inner ear drum

Answer 8

To channel soundwaves into your inner so you can hear. Cupping a hand beside your ear also helps you hear better.

Answer 9

best design for stereo and getting out of the womb

Answer 10

to enable the sound to go on to the celia hairs which vibrate and allows sound