Hearing, or auditory perception, is the ability to perceive sounds by detecting vibrations,changes in the pressure of the surrounding medium, through an organ such as the ear.
The hearing structures of many species have defense mechanisms against injury. For example, the muscles of the middle ear in many mammals contract reflexively in reaction to loud sounds which may otherwise injure the hearing ability of the organism.
Hearing underwater: Hearing threshold and the ability to localize sound sources are reduced underwater in humans but not in aquatic animals, including whales, seals, and fishes which have ears adapted to process water borne sound.
Key words: hearing; hearing+