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Some Animal Stories
Have you ever wondered if fish have ears? Can they hear as we know it or how exactly to they hear? Well, fish do in actual fact have ears but obviously they don’t hear as we know it. Aside from the obvious difference in medium (i.e. they live in water), they actually “hear” by changes of pressure through the ridges on their body.
How about snakes – can they hear? Yes, snakes can hear and they do this through their jawbone and through a traditional inner ear. Snakes are rather fortunate then because they effectively have two types of hearing mechanisms – all the better to hear and catch their prey.
Hmmm, here’s another one – male mosquitoes “hear” with thousands of tiny hairs that grow on their antennae. That’s why they go deaf when you clap them between your hands… or is it because they die maybe J
A cat on the other hand has 32 muscles in each ear and each ear can turn independently.
Ever heard your tummy grumble, well cicadas have their ‘ears’ in their stomachs – their “grumbling” must be loud and clear.
Crickets stick their knees up in the air because that’s where their ears are (in their knees). Ok so not sure if that’s why they stick them up in the air but it makes sense.
Ever seen a dog respond to something that you were totally oblivious to. Well that’s because they can hear at much higher frequencies than we do. Did you ever see the film “The Doberman Gang” – a good one that illustrates that fact.
Talk about high frequencies: -
- People can hear in the range of 20 Hz to 20,000 Hz;
- Cats hear in the range 45 Hz to 64,000 Hz.
- Mice hear in the range 1000 Hz all the way up to 91,000 Hz
- Bats hear up to 110,000 Hz
- Porpoises take top prize in the high frequency stakes. They can hear up to 150,000 Hz.
Some ear facts
Hearing is one of the 5 senses of the body.
The ear contains the smallest bones in the body. Scientifically they are called the malleus, incus and stapes. Commonly, or in layman’s terms, they are known as the hammer, anvil and stirrup. All three bones can fit together on a penny.
Your ear drum moves less than a billionth of an inch when hearing.
You get a new ear canal every year! The ear canal skin is constantly growing outward at a rate of 1.3 inches every year. Just as well it just falls off – imagine what you’d have hanging out of your ear if it didn’t!
Have you ever suddenly woken up, positive you heard something, but with no idea what it was? Well, just as our subconscious is “wide awake” while we are sleeping, so too does the ear continue to hear while we’re asleep. Our brain just shuts out the noises. Makes you think doesn’t it – are we really asleep?
The inner ear is effectively 2 organs – one containing the cochlea and the other the semi-lunar canals (or semi-circular canals). The cochlea is responsible for our hearing but the semi-lunar canals aid our balance.
Do you like to sit right in front of the speakers when you go to a music concert? You certainly hear the music loud and clear but by doing that, it can expose you to 120 decibels. And so – your point? I hear you say indignantly – well at that level, it will begin to damage your hearing after only a very brief seven and a half minutes. How long were you going to sit there for – 120 minutes maybe? That’s quite a whack of noise you are subjecting your ears to only to end up with a kind of hearing loss known as a “noise induced hearing loss”. This damage is not reversible, so no jokes here!
Our ears help us detect sound. They convert sound waves into nerve impulses that are sent to the brain.
Our ears are a little like antennae really – their job is to pick up the sound waves from the air. After that, it’s up to the brain to do the grunt work and translate those impulses into something that makes sense that we understand.
There is more to the ear than meets the eye i.e. the part that you can see on the outside of your head. If you go literally by their names, you have 3 ears – an outer ear, a middle ear and an inner ear.
The outer ear (the part you can see) catches sound waves
The middle ear (the part just behind the ear drum) takes that sound wave (pressure) and amplifies it.
The inner ear has 2 functions: to convert the sound waves received from the outside into nerve impulses that can be translated by the brain and to assist us with balance
To keep the pressure inside the ear the same as that outside the ear (equalize pressure), the middle ear also contains the Eustachian tube. This tube helps maintaining that tender balance of pressure inside and outside the ear as well has helping drain mucus.
Ear infections are more common in children. This is not because their ears are more susceptible to infection but rather because of their developing immune systems. It also has something to do with the fact that their Eustachian tubes differ to those of adults.
The inner ear is well protected. It is found inside the temporal bone which also happens to be the hardest bone in the human body.
Sounds waves arrive at the ear via the air surrounding us. Within the cochlea inside the inner ear, there exists a liquid and so it is said that sound waves are passed from “air to liquid” in the inner air.
The cochlea contains minute hair cells which react to sound waves. This reaction triggers chemicals that are released and sent to the brain as nerve impulses.
Due to the sensitivity of the inner ear, any abnormalities there can cause deafness.
Ear wax is produced by skin glands in the ear canal and has the important role of protecting the ear by lubricating it as well as cleaning it of dirt and dust that finds its way into the ear.
Sometimes our hearing can be impaired if there is an excessive ear wax build up. This is especially the case if the wax is pressed hard against the eardrum by attempting to clean the ear with a cotton bud or some other object for example.
Wax normally comes out of your ear naturally so don’t try and remove it yourself. Aside from compacting or pushing ear wax further down the ear against the ear drum thus impairing hearing, there is the risk of perforating the ear drum.
In some cultures around the world, it is common practice to pierce the ears of men and women alike adorning them with jewelry and in some cases with large seemingly unattractive “jewelry” that can only be described as a large hole in the bottom part of the earlobe filled with what appears to be a doughnut shaped piece of wood i.e. circular piece with a hole in the middle.
Practices like this have been commonplace around the world for thousands of years for both cultural and cosmetic reasons.
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