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BOTTLENOSE DOLPHINS - Communication and Echolocation

Autor /Dacjan Dodano /10.11.2011

Dolphins probably rely on sound production and reception to navigate, communicate, and hunt in dark or murky waters. Under these conditions, sight is of little use. The odontocete larynx does not possessvocal cords, but researchers have theorized that at least some sound production originates in the larynx. Early studies suggested that "whistles"were generated in the larynx while "clicks" were produced in the nasal sac region. Sounds are probably produced by movements of air in the trachea and nasal sacs. During some vocalizations, bottlenose dolphins actually release air from the blowhole, but scientist believe that these bubble trails and clouds are a visual display and not necessary for producing sound.

The sounds vary in volume, wavelength, frequency, and pattern. Bottlenose dolphins identify themselves with a signature whistle. However, scientists have found no evidence of a dolphin language. A mother dolphin may whistle to her calf almost continuously for several days after giving birth. This acoustic imprinting helps the calf earn to identify its mother. The brain receives the sound waves in the from of nerve impulses, which relay the messages of sound and enable the dolphin to interpret the sound's meaning. By this complex system of echolocation, odontocetes can determine size, shape, speed, distance, direction, and even some of the internal structure of objects in the water.

Bottlenose dolphins are able to learn and later recognize the echo signatures returned by preffered prey species. Many of the details of echolocation are not completely understood. Research on echolocation continues. are able to learn and later recognize the echo signatures returned by preffered prey species. Many of the details of echolocation are not completely understood. Research on echolocation continues. are able to learn and later recognize the echo signatures returned by preffered prey species. Many of the details of echolocation are not completely understood. Research on echolocation continues.

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