Changes

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. However, even without a surface or subsurface-mounted tympanic membrane, many "earless" reptiles can indeed "hear", though to varying degrees.  

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. However, even without a surface or subsurface-mounted tympanic membrane, many "earless" reptiles can indeed "hear", though to varying degrees.  

Gekkonids who vocalize have both high sensitivity and high frequency, up into the 10,000Hz range.

Lizards such as gekkonids can vocalize (different to the rapid expellation of air resulting in a hiss) and have both high sensitivity and high frequency, up into the 10,000Hz range. Although very few studies have been done on gekkonid vocalization, research seems to indicate that in some species, it may play a role in territoriality and social groupings.

==Anatomy==

==Anatomy==