Essay on Bottlenose Dolphins

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Bottlenose Dolphins This essay is NOT formatted Bottlenose dolphins are among the most vocal of the nonhuman animals and exhibit remarkable development of the sound production and auditory mechanisms. This can be seen in audition, which is shown in the animal’s highly refined echolocation ability, and in tightly organized schools in which they live that are made up by sound communication. In testing the communication skills of dolphins, extensive studies have been done on vocal mimicry, in which the animal imitates computer-generated sounds in order to test motor control in terms of cognitive ability. Language comprehension on the other hand has been tested through labeling of objects, which has proven to be…show more content…
1986). In order to understand the complexity of these highly mechanized acoustic systems, it is necessary to learn the process for which the dolphin hears. In most water-adapted cetaceans, tissue conduction is the primary route of sound conduction to the middle ear. The isolation of the bullae shows an adaptation for tissue conducted sound. The lower jaw contains fat that is closely associated with the impedance of seawater. The lower jawbone of most odontocetes becomes broadened and quite thin posteriorly, and the fat forms an oval shape that closely corresponds to the area of minimum thickness of the jaw. This fat body leads directly to the bulla, producing a sound path to the ear structures located deep within the head. Paired and single air sacs are scattered throughout the skull, which serve to channel these tissue-conducted sounds (Popov & Supin, 1991). Other than this description, there are still more studies needed to determine the function of the middle ear and the type of bone conduction that occurs within the bulla. Due to detailed audiograms, dolphins have been shown to have the ability to detect high-frequency sounds. In an experiment by Johnson (1966) as cited in Schusterman et al. (1986), sine-wave sounds ranging in frequency from 75 Hz to 150 Hz were presented to a bottle-nosed dolphin. The animal was trained to swim in a stationary area within a stall and to
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