The ear is the sense organ that detects sounds. In Biology, an organ ( Latin: organum, "instrument tool" from Greek όργανον - organon "organ instrument Sound' is Vibration transmitted through a Solid, Liquid, or Gas; particularly sound means those vibrations composed of Frequencies The vertebrate ear shows a common biology from fish to humans, with variations in structure according to order and species. Vertebrates are members of the Subphylum Vertebrata, Chordates with backbones or spinal columns The grouping sometimes includes Fish are aquatic Vertebrate animals that are typically ectothermic (previously Cold-blooded) covered with scales, and equipped with two Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus It not only acts as a receiver for sound, but plays a major role in the sense of balance and body position. The ear is part of the auditory system. The auditory system is the Sensory system for the sense of hearing.
The word "ear" may be used correctly to describe the entire organ or just the visible portion. In most animals, the visible ear is a flap of tissue that is also called the pinna. The pinna ( Latin for Feather) is the visible part of the Ear that resides outside of the head (this may also be referred to as the auricle or The pinna may be all that shows of the ear, but it serves only the first of many steps in hearing and plays no role in the sense of balance. In people, the pinna is often called the auricle. Vertebrates have a pair of ears, placed symmetrically on opposite sides of the head. This arrangement aids in the ability to localize sound sources.
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Introduction to ears and hearing
Audition is the scientific name for the perception of sound. Sound is a form of energy that moves through air, water, and other matter, in waves of pressure. Sound' is Vibration transmitted through a Solid, Liquid, or Gas; particularly sound means those vibrations composed of Frequencies Sound is the means of auditory communication, including frog calls, bird songs and spoken language. Although the ear is the vertebrate sense organ that recognizes sound, it is the brain and central nervous system that "hears". Sound waves are perceived by the brain through the firing of nerve cells in the auditory portion of the central nervous system. Neurons (ˈnjuːɹɒn also known as neurones and nerve cells) are responsive cells in the Nervous system that process and transmit information The ear changes sound pressure waves from the outside world into a signal of nerve impulses sent to the brain.
The outer part of the ear collects sound. That sound pressure is amplified through the middle portion of the ear and, in land animals, passed from the medium of air into a liquid medium. Sound pressure is the local Pressure deviation from the ambient (average or equilibrium pressure caused by a Sound Wave. The change from air to liquid occurs because air surrounds the head and is contained in the ear canal and middle ear, but not in the inner ear. The inner ear is hollow, embedded in the temporal bone, the densest bone of the body. The temporal bones are situated at the sides and base of the Skull. The hollow channels of the inner ear are filled with liquid, and contain a sensory epithelium that is studded with hair cells. Hair cells are the Sensory receptors of both the Auditory system and the Vestibular system in all Vertebrates. The microscopic "hairs" of these cells are structural protein filaments that project out into the fluid. The hair cells are mechanoreceptors that release a chemical neurotransmitter when stimulated. Sound waves moving through fluid push the filaments; if the filaments bend over enough it causes the hair cells to fire. In this way sound waves are transformed into nerve impulses. In vision, the rods and cones of the retina play a similar role with light as the hair cells do with sound. In Psychology, visual perception is the ability to interpret information from Visible light reaching the Eyes The resulting Perception is also The vertebrate retina is a light sensitive part inside the inner layer of the Eye. The nerve impulses travel from the left and right ears through the eighth cranial nerve to both sides of the brain stem and up to the portion of the cerebral cortex dedicated to sound. Cranial nerves are Nerves that emerge directly from the Brain stem in contrast to Spinal nerves which emerge from segments of the Spinal cord. The cerebral cortex is a structure within the Brain that plays a key role in Memory, Attention, perceptual Awareness, Thought, This auditory part of the cerebral cortex is in the temporal lobe. The temporal lobes are parts of the cerebrum that are involved in speech, Memory, and Hearing.
The part of the ear that is dedicated to sensing balance and position also sends impulses through the eighth cranial nerve, the VIIIth nerve's Vestibular Portion. Those impulses are sent to the vestibular portion of the central nervous system. The human ear can generally hear sounds with frequencies between 20 Hz and 20 kHz (the audio range). The hertz (symbol Hz) is a measure of Frequency, informally defined as the number of events occurring per Second. The hertz (symbol Hz) is a measure of Frequency, informally defined as the number of events occurring per Second. Sound' is Vibration transmitted through a Solid, Liquid, or Gas; particularly sound means those vibrations composed of Frequencies Although the sensation of hearing requires an intact and functioning auditory portion of the central nervous system as well as a working ear, human deafness (extreme insensitivity to sound) most commonly occurs because of abnormalities of the inner ear, rather than the nerves or tracts of the central auditory system. [1]
Mammalian ear
The shape of outer ear of mammals varies widely across species. The pinna ( Latin for Feather) is the visible part of the Ear that resides outside of the head (this may also be referred to as the auricle or However the inner workings of mammalian ears (including humans') are very similar.
Parts of the ear
Outer ear (pinna, ear canal, surface of ear drum)
The outer ear is the most external portion of the ear. The outer ear is the external portion of the Ear, which consists of the pinna, Concha, and Auditory meatus. The outer ear includes the pinna (also called auricle), the ear canal, and the very most superficial layer of the ear drum (also called the tympanic membrane). The pinna ( Latin for Feather) is the visible part of the Ear that resides outside of the head (this may also be referred to as the auricle or In humans, and almost all vertebrates, the only visible portion of the ear is the outer ear. Although the word "ear" may properly refer to the pinna (the flesh covered cartilage appendage on either side of the head), this portion of the ear is not vital for hearing. The outer ear does help get sound (and imposes filtering), but the ear canal is very important. Unless the canal is open, hearing will be dampened. Ear wax (medical name - cerumen) is produced by glands in the skin of the outer portion of the ear canal. Earwax, also known by the Medical term cerumen, is a yellowish waxy substance secreted in the Ear canal of Humans and many other This outer ear canal skin is applied to cartilage; the thinner skin of the deep canal lies on the bone of the skull. Only the thicker cerumen-producing ear canal skin has hairs. The outer ear ends at the most superficial layer of the tympanic membrane. The tympanic membrane is commonly called the ear drum.
The pinna helps direct sound through the ear canal to the tympanic membrane (eardrum). The tympanic membrane (also tympanum or myrinx is a thin membrane that separates the External ear from the Middle ear. The framework of the auricle consists of a single piece of yellow fibrocartilage with a complicated relief on the anterior, concave side and a fairly smooth configuration on the posterior, convex side. The Darwinian tubercle, which is present in some people, lies in the descending part of the helix and corresponds to the true ear tip of the long-eared mammals. The lobule merely contains subcutaneous tissue. [2] In some animals with mobile pinnae (like the horse), each pinna can be aimed independently to better receive the sound. For these animals, the pinnae help localize the direction of the sound source. Human beings localize sound within the central nervous system, by comparing arrival-time differences and loudness from each ear, in brain circuits that are connected to both ears. This process is commonly referred to as EPS, or Echo Positioning System.
Human outer ear and culture
The auricles also have an effect on facial appearance. In Western societies, protruding ears (present in about 5% of ethnic Europeans) have been considered unattractive, particularly if asymmetric. The European peoples are the various Nations and Ethnic groups of Europe. The first surgery to reduce the projection of prominent ears was published in the medical literature in 1881.
The ears have also been ornamented with jewelry for thousands of years, traditionally by piercing of the earlobe. Earrings are jewelry attached to the ear through a piercing in the Earlobe or some other external part of the ear (except in the case of clip earrings On the Ear of Humans and many other animals the earlobe('lobulus auriculæ' sometimes simply lobe or lobule) is the soft lower part of the external ear In some cultures, ornaments are placed to stretch and enlarge the earlobes to make them very large. Tearing of the earlobe from the weight of heavy earrings, or from traumatic pull of an earring (for example by snagging on a sweater being removed), is fairly common. [3] The repair of such a tear is usually not difficult.
A cosmetic surgical procedure to reduce the size or change the shape of the ear is called an otoplasty. Otoplasty, is a Cosmetic surgery to change the appearance of a person's external ears In the rare cases when no pinna is formed (atresia), or is extremely small (microtia) reconstruction the auricle is possible. Microtia (meaning 'Small ear' is a congenital deformity of the pinna (outer ear Most often, a cartilage graft from another part of the body (generally, rib cartilage) is used to form the matrix of the ear, and skin grafts or rotation flaps are used to provide the covering skin. However, when babies are born without an auricle on one or both sides, or when the auricle is very tiny, the ear canal is ordinarily either small or absent, and the middle ear often has deformities. The initial medical intervention is aimed at assessing the baby's hearing and the condition of the ear canal, as well as the middle and inner ear. Depending on the results of tests, reconstruction of the outer ear is done in stages, with planning for any possible repairs of the rest of the ear. [4][5][6]
Middle ear
The middle ear, an air-filled cavity behind the ear drum (tympanic membrane), includes the three ear bones or ossicles: the malleus (or hammer), incus (or anvil), and stapes (or stirrup). The middle ear is the portion of the ear internal to the Eardrum, and external to the Oval window of the Cochlea. The ossicles (also called auditory ossicles) are the three smallest Bones in the human body The opening of the Eustachian tube is also within the middle ear. The Eustachian tube (or auditory tube) is a tube that links the Pharynx to the Middle ear. The malleus has a long process (the manubrium, or handle) that is attached to the mobile portion of the eardrum. The incus is the bridge between the malleus and stapes. The stapes is the smallest named bone in the human body. The three bones are arranged so that movement of the tympanic membrane causes movement of the malleus, which causes movement of the incus, which causes movement of the stapes. When the stapes footplate pushes on the oval window, it causes movement of fluid within the cochlea (a portion of the inner ear).
In humans and other land animals the middle ear (like the ear canal) is normally filled with air. Unlike the open ear canal, however, the air of the middle ear is not in direct contact with the atmosphere outside the body. The Eustachian tube connects from the chamber of the middle ear to the back of the pharynx. The Eustachian tube (or auditory tube) is a tube that links the Pharynx to the Middle ear. The middle ear is very much like a specialized paranasal sinus, called the tympanic cavity; it, like the paranasal sinuses, is a hollow mucosa-lined cavity in the skull that is ventilated through the nose. Paranasal sinuses are air-filled spaces communicating with the nasal cavity within the bones of the Skull and face The mastoid portion of the human temporal bone, which can be felt as a bump in the skull behind the pinna, also contains air, which is ventilated through the middle ear.
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Normally, the Eustachian tube is collapsed, but it gapes open both with swallowing and with positive pressure. The malleus or hammer is a hammer-shaped small Bone or ossicle of the Middle ear which connects with the Incus and is attached The tensor tympani, the larger of the two muscles of the Tympanic cavity, is contained in the bony canal above the osseous portion of the Auditory tube, from which For the record label see Incus Records. The incus or anvil is the Anvil -shaped small Bone or ossicle The stapedius is the smallest striated muscle in the Human body For more uses of the word labyrinth, see Labyrinth (disambiguation The labyrinth is a System of fluid passages in the The stapes or stirrup is the stirrup-shaped small Bone or ossicle in the Middle ear which attaches the Incus to the Fenestra ovalis The ear canal ( external auditory meatus, external acoustic meatus) is a tube running from the Outer ear to the Middle ear. The tympanic membrane (also tympanum or myrinx is a thin membrane that separates the External ear from the Middle ear. The Eustachian tube (or auditory tube) is a tube that links the Pharynx to the Middle ear. The tympanic cavity is a small cavity surrounding the bones of the Middle ear. The middle ear is the portion of the ear internal to the Eardrum, and external to the Oval window of the Cochlea. When taking off in an airplane, the surrounding air pressure goes from higher (on the ground) to lower (in the sky). The air in the middle ear expands as the plane gains altitude, and pushes its way into the back of the nose and mouth. On the way down, the volume of air in the middle ear shrinks, and a slight vacuum is produced. Active opening of the Eustachian tube is required to equalize the pressure between the middle ear and the surrounding atmosphere as the plane descends. The diver also experiences this change in pressure, but with greater rates of pressure change; active opening of the Eustachian tube is required more frequently as the diver goes deeper into higher pressure.
The arrangement of the tympanic membrane and ossicles works to efficiently couple the sound from the opening of the ear canal to the cochlea. There are several simple mechanisms that combine to increase the sound pressure. The first is the "hydraulic principle". The surface area of the tympanic membrane is many times that of the stapes footplate. Sound energy strikes the tympanic membrane and is concentrated to the smaller footplate. A second mechanism is the "lever principle". The dimensions of the articulating ear ossicles lead to an increase in the force applied to the stapes footplate compared with that applied to the malleus. A third mechanism channels the sound pressure to one end of the cochlea, and protects the other end from being struck by sound waves. In humans, this is called "round window protection", and will be more fully discussed in the next section.
Abnormalities such as impacted ear wax (occlusion of the external ear canal), fixed or missing ossicles, or holes in the tympanic membrane generally produce conductive hearing loss. Conductive hearing loss may also result from middle ear inflammation causing fluid build-up in the normally air-filled space. Tympanoplasty is the general name of the operation to repair the middle ear's tympanic membrane and ossicles. Grafts from muscle fascia are ordinarily used to rebuild an intact ear drum. Sometimes artificial ear bones are placed to substitute for damaged ones, or a disrupted ossicular chain is rebuilt in order to conduct sound effectively.
Inner ear: cochlea, vestibule, and semi-circular canals
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The inner ear includes both the organ of hearing (the cochlea) and a sense organ that is attuned to the effects of both gravity and motion (labyrinth or vestibular apparatus). The inner Ear is the bony labyrinth, a system of passages comprising two main functional parts the organ of hearing or Cochlea The posterior semicircular canal is a part of the Vestibular system and detects rotations of the head in the Sagittal plane The superior semicircular canal ( anterior semicircular canal) is a part of the Vestibular system and detects rotation of the head around a rostral-caudal (anterior-posterior The utricle, or utriculus along with the Saccule is one of the two Otolith organs located in the Vertebrate Inner ear. The lateral or horizontal canal (external semicircular canal is the shortest of the three canals "Vestibulum" and "vestibule" redirect here For other uses see Vestibule (disambiguation. The cochlea is the auditory portion of the Inner ear. Its core component is the Organ of Corti, the sensory organ of hearing, which is distributed along Introduction The saccule is a bed of sensory cells situated in the inner ear The inner Ear is the bony labyrinth, a system of passages comprising two main functional parts the organ of hearing or Cochlea The cochlea is the auditory portion of the Inner ear. Its core component is the Organ of Corti, the sensory organ of hearing, which is distributed along For more uses of the word labyrinth, see Labyrinth (disambiguation The labyrinth is a System of fluid passages in the The balance portion of the inner ear consists of three semi-circular canals and the vestibule. The semicircular canals are three half-circular interconnected tubes located inside each Ear that are the equivalent of three Gyroscopes located in three orthogonal "Vestibulum" and "vestibule" redirect here For other uses see Vestibule (disambiguation. The inner ear is encased in the hardest bone of the body. Within this ivory hard bone, there are fluid-filled hollows. Within the cochlea are three fluid filled spaces: the tympanic canal, the vestibular canal, and the middle canal. The eighth cranial nerve comes from the brain stem to enter the inner ear. When sound strikes the ear drum, the movement is transferred to the footplate of the stapes, which presses into one of the fluid-filled ducts of the cochlea. The fluid inside this duct is moved, flowing against the receptor cells of the Organ of Corti, which fire. The organ of Corti (or spiral organ) is the organ in the Inner ear of Mammals that contains auditory sensory cells or " Hair cells " These stimulate the spiral ganglion, which sends information through the auditory portion of the eighth cranial nerve to the brain. The spiral ganglion is the group of nerve cells that serve the sense of hearing by sending a representation of sound from the Cochlea to the Brain.
Hair cells are also the receptor cells involved in balance, although the hair cells of the auditory and vestibular systems of the ear are not identical. Vestibular hair cells are stimulated by movement of fluid in the semicircular canals and the utricle and saccule. Firing of vestibular hair cells stimulates the Vestibular portion of the eighth cranial nerve. [7]
Damage to the human ear
Outer ear trauma
Auricle
The auricle can be easily damaged. Because it is skin-covered cartilage, with only a thin padding of connective tissue, rough handling of the ear can cause enough swelling to jeopardize the blood-supply to its framework, the auricular cartilage. That entire cartilage framework is fed by a thin covering membrane called the perichondrium (meaning literally: around the cartilage). The perichondrium is a layer of dense irregular Connective tissue which surrounds the Cartilage of developing bone Any fluid from swelling or blood from injury that collects between the perichondrium and the underlying cartilage puts the cartilage in danger of being separated from its supply of nutrients. If portions of the cartilage starve and die, the ear never heals back into its normal shape. Instead, the cartilage becomes lumpy and distorted. Wrestler's Ear is one term used to describe the result, because wrestling is one of the most common ways such an injury occurs. Cauliflower ear is another name for the same condition, because the thickened auricle can resemble that vegetable. Cauliflower ear (also hematoma auris or perichondrial hematoma) is a condition most common among amateur wrestlers, rugby players, mixed
The lobule of the ear (ear lobe) is the one part of the human auricle that normally contains no cartilage. On the Ear of Humans and many other animals the earlobe('lobulus auriculæ' sometimes simply lobe or lobule) is the soft lower part of the external ear Instead, it is a wedge of adipose tissue (fat) covered by skin. "Adipose" redirects here For the Doctor Who monster see " Partners in Crime " There are many normal variations to the shape of the ear lobe, which may be small or large. Tears of the earlobe can be generally repaired with good results. Since there is no cartilage, there is not the risk of deformity from a blood clot or pressure injury to the ear lobe.
Other injuries to the external ear occur fairly frequently, and can leave a major deformity. Some of the more common ones include, laceration from glass, knives, and bite injuries, avulsion injuries, cancer, frostbite, and burns. In Medicine, a wound is a type of Injury in which the Skin is torn cut or punctured (an open wound or where blunt force trauma Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled Frostbite ( congelatio in Medical terminology) is the Medical condition whereby damage is caused to Skin and other tissues
Ear canal
Ear canal injuries can come from firecrackers and other explosives, and mechanical trauma from placement of foreign bodies into the ear. The ear canal is most often self-traumatized from efforts at ear cleaning. The outer part of the ear canal rests on the flesh of the head; the inner part rests in the opening of the bony skull (called the external auditory meatus). The ear canal ( external auditory meatus, external acoustic meatus) is a tube running from the Outer ear to the Middle ear. The skin is very different on each part. The outer skin is thick, and contains glands as well as hair follicles. A gland is an organ in an animal's body that synthesizes a substance for release such as Hormones or Breast milk, often into the Bloodstream A hair follicle is part of the Skin that grows Hair by packing old cells together The glands make cerumen (also called ear wax). Earwax, also known by the Medical term cerumen, is a yellowish waxy substance secreted in the Ear canal of Humans and many other The skin of the outer part moves a bit if the pinna is pulled; it is only loosely applied to the underlying tissues. The skin of the bony canal, on the other hand, is not only among the most delicate skin in the human body, it is tightly applied to the underlying bone. A slender object used to blindly clean cerumen out of the ear often results instead with the wax being pushed in, and contact with the thin skin of the bony canal is likely to lead to laceration and bleeding.
Middle ear trauma
Like outer ear trauma, middle ear trauma most often comes from blast injuries and insertion of foreign objects into the ear. Skull fractures that go through the part of the skull containing the ear structures (the temporal bone) can also cause damage to the middle ear. Small perforations of the tympanic membrane usually heal on their own, but large perforations may require grafting. Displacement of the ossicles will cause a conductive hearing loss that can only be corrected with surgery. Forcible displacement of the stapes into the inner ear can cause a sensory neural hearing loss that cannot be corrected even if the ossicles are put back into proper position. Because human skin has a top waterproof layer of dead skin cells that are constantly shedding, displacement of portions of the tympanic membrane or ear canal into the middle ear or deeper areas by trauma can be particularly traumatic. If the displaced skin lives within a closed area, the shed surface builds up over months and years and forms a cholesteatoma. Cholesteatoma is a destructive and expanding sac in the middle ear and/or Mastoid process. The -oma ending of that word indicates a tumour in medical terminology, and although cholesteatoma is not a neoplasm (but a skin cyst), it can expand and erode the ear structures. The treatment for cholesteatoma is surgical.
Inner ear trauma
There are two principal damage mechanisms to the inner ear in industrialized society, and both injure hair cells. The first is exposure to elevated sound levels (noise trauma), and the second is exposure to drugs and other substances (ototoxicity). Ototoxicity is damage of the Ear ( oto) specifically the Cochlea or auditory nerve and sometimes the Vestibulum, by a Toxin
In 1972 the U. S. EPA told Congress that at least 34 million people were exposed to sound levels on a daily basis that are likely to lead to significant hearing loss. Noise health effects are the Health consequences of elevated Sound levels Elevated workplace or other Noise can cause Hearing impairment [8] The worldwide implication for industrialized countries would place this exposed population in the hundreds of millions.
Vestigial structures
It has long been known that humans, and indeed other primates such as the orangutan and chimpanzee have ear muscles that are minimally developed and non-functional, yet still large enough to be easily identifiable. The orangutans are two Species of great apes known for their intelligence long arms and reddish-brown hair Chimpanzee (often shortened to chimp) is the common name for the two extant Species of Apes in the Genus Pan. Muscle (from Latin musculus, diminutive of mus "mouse" is contractile tissue of the body and is derived from the [9] These undeveloped muscles are vestigial structures. Vestigiality describes homologous characters of Organisms which have lost all or most of their original function in a species through A muscle that cannot move the ear, for whatever reason, can no longer be said to have any biological function. This serves as evidence of homology between related species. In Evolutionary biology, homology has come to mean any similarity between characters that is due to their shared ancestry. In humans there is variability in these muscles, such that some people are able to move their ears in various directions, and it has been said that it may be possible for others to gain such movement by repeated trials. [9]
Non-vertebrate hearing organs
Only vertebrate animals have ears, although many invertebrates are able to detect sound using other kinds of sense organs. In insects, tympanal organs are used to hear distant sounds. A Tympanal organ is a hearing organ in Insects, consisting of a membrane ( tympanum) stretched across a frame backed by an air sac They are not confined to the head, but can occur in different locations depending on the group of insects. [10]
Simpler structures allow arthropods to detect near field sounds. Arthropods are Animals belonging to the Phylum Arthropoda (from Greek ἄρθρον arthron, " Joint " The near field and far field of an antenna or other isolated source of Electromagnetic radiation are regions around the source where different parts of the field Spiders and cockroaches, for example, have hairs on their legs which are used for detecting sound. Caterpillars may also have hairs on their body that perceive vibrations[11] and allow them to respond to the sound.
References
- ^ Greinwald, John H. Jr MD; Hartnick, Christopher J. MD The Evaluation of Children With Hearing Loss. Archives of Otolaryngology — Head & Neck Surgery. 128(1):84-87, January 2002
- ^ Stenström, J. Sten: Deformities of the ear; In: Grabb, W. , C. , Smith, J. S. (Edited): “Plastic Surgery”, Little, Brown and Company, Boston, 1979, ISBN 0-316-32269-5 (C), ISBN 0-316-32268-7 (P)
- ^ Deborah S. Sarnoff, Robert H. Gotkin, and Joan Swirsky (2002). Instant Beauty: Getting Gorgeous on Your Lunch Break. St. Martin's Press. ISBN 031228697X.
- ^ Lam SM. Edward Talbot Ely: father of aesthetic otoplasty. [Biography. Historical Article. Journal Article] Archives of Facial Plastic Surgery. 6(1):64, 2004 Jan-Feb.
- ^ Siegert R. Combined reconstruction of congenital auricular atresia and severe microtia. [Evaluation Studies. Journal Article] Laryngoscope. 113(11):2021-7; discussion 2028-9, 2003 Nov.
- ^ Trigg DJ. Applebaum EL. Indications for the surgical repair of unilateral aural atresia in children. [Review] [33 refs] [Journal Article. Review] American Journal of Otology. 19(5):679-84; discussion 684-6, 1998 Sep.
- ^ Anson and Donaldson, Surgical Anatomy of the Temporal Bone, 4th Edition, Raven Press, 1992
- ^ Senate Public Works Committee, Noise Pollution and Abatement Act of 1972, S. Rep. No. 1160, 92nd Cong. 2nd session.
- ^ a b Darwin, Charles (1871). Charles Robert Darwin (February 12 1809 &ndash April 19 1882 was an English naturalist, who realised and demonstrated that all Species of life The Descent of Man, and Selection in Relation to Sex. The Descent of Man and Selection in Relation to Sex is a book on Evolutionary theory by English naturalist Charles Darwin, first John Murray: London.
- ^ Yack, JE, and JH Fullard, 1993. What is an insect ear? Ann. Entomol. Soc. Am. 86(6): 677-682.
- ^ Scoble, MJ. 1992. The Lepidoptera: Form, function, and diversity. Oxford Univ. Press.
See also
- WikiSaurus:ear — the WikiSaurus list of synonyms and slang words for ears in many languages
- Absolute threshold of hearing
- Acoustic reflex
- Cerumen
- Cholesteatoma
- Ear pick
- Ear piercing
- Ear piercing instrument
- Earring
- Georg von Békésy, winner of the 1961 Nobel Prize for his research on the cochlea
- Glossary of medical terms related to communications disorders
- Loudness
- Musical acoustics
- Noise health effects
- Otoplasty External Ear Surgery
- Pitch (music)
- Sound localization
- Timbre
- Tinnitus
- Vestibular system
- Auditory brainstem response (ABR) test
External links
- Protein behind hearing
- 3D Ear page
- Details of various ear problems
- Ear wiggling mechanism unmasked
- Cotton swabs can pose serious health risk: coroner from ctv.ca
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