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[[Image:Lizard_ear.bmp|150px|thumb|right|Lizard ear]]  
 
[[Image:Lizard_ear.bmp|150px|thumb|right|Lizard ear]]  
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Most of the lizards seem to hear in the same range as the green iguana (500 to 4,000Hz range), with a sensitivity peak at 700 Hz, equal to about 24 dB. For lizards lacking a tympanic membrane, such as the lesser (Northern) earless lizard (''Holbrookia maculata''), hearing is limited to lower frequencies.  
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Most of the lizards seem to hear in the same range as the green iguana (500 to 4,000Hz range), with a sensitivity peak at 700 Hz, equal to about 24 dB. For lizards lacking a tympanic membrane, such as the lesser (Northern) earless lizard (''Holbrookia maculata'') and many fossorial (burrowing) and semi-fossorial lizards (for example the legless Anniella), hearing is limited to lower frequencies.  
    
Gekkonids who vocalize have both high sensitivity and high frequency, up into the 10,000Hz range.
 
Gekkonids who vocalize have both high sensitivity and high frequency, up into the 10,000Hz range.
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The stapes (or stirrup) is a single bone that connects the eardrum to the inner ear; it crosses the middle ear cavity, from the inside of the tympanic membrane, its inner end fitted inside the oval opening. The outer end of the stapes has a cartilage cap which comes into contact with the tympanic membrane. In some reptiles, this cartilage, called the extrastapes, is attached to the quadrate, the primary support of the lower jaw. The upper and lower jaws contain several bones not found in mammals.
 
The stapes (or stirrup) is a single bone that connects the eardrum to the inner ear; it crosses the middle ear cavity, from the inside of the tympanic membrane, its inner end fitted inside the oval opening. The outer end of the stapes has a cartilage cap which comes into contact with the tympanic membrane. In some reptiles, this cartilage, called the extrastapes, is attached to the quadrate, the primary support of the lower jaw. The upper and lower jaws contain several bones not found in mammals.
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The inner ear cavity comprises organs related to balance (the semicircular canals, utricle, and saccule) and hearing (cochlear duct). The cochlear duct and the saccule are both suspended in perilymphatic fluid; the cochlear is also filled with this fluid. The inside of the duct has two specialized regions, the papilla basilaris and the smaller macula lagenae. Both of these areas are actually clusters of sensory cells. These areas also have cilia, which are embedded in a membrane within the cochlear duct. These sensory cells give rise to the auditory nerve (the VIIIth cranial nerve).
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The inner ear cavity comprises organs related to balance (the semicircular canals, utricle, and saccule) and hearing (cochlear duct). The cochlear duct and the saccule are both suspended in perilymphatic fluid; the cochlear is also filled with this fluid.  
    
There is a single ossicle, the columella.
 
There is a single ossicle, the columella.
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==Function==
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