interesting dolphin facts for kids
Dolphins are extremely and almost constantly vocal. They are capable of two kinds of sounds. A specialized mechanism in the nasal passages just below the blow-hole enables them to emit short, pulse-type sounds. These sounds, called clicks, can be produced in such rapid succession as to sound like a buzz or even a duck like quack. The clicks are used as a form of sonar, in which echoes of sounds from surrounding objects enable the animals to detect obstacles, other dolphins, fish, and even tiny bits of matter in the water. Deeper in the respiratory system--presumably in the larynx--dolphins produce another type of sound: a high pitched whistle of squeal, which is capable of rapid pitch changes. The whistles differ from the clicks in being essentially single tones. Apparently the dolphin used the whistles to communicate a particular emotional state and thus influence the behavior of other dolphins. Typically, the squeals denote alarm or sexual excitement.