Gabrielle Warren, age 11, of Miami, Fla, for her question:
HOW DO DOLPHINS COMMUNICATE WITH ONE ANOTHER?
Dolphins are small, whalelike mammals. Scientists tell us that dolphins communicate with one another by making sounds that include whistles, clicks and barks. A bottle nose dolphin can even imitate some sounds of the human voice.
The bottle nosed dolphin is considered by scientists to be one of the most intelligent animals in the world. It is rated in intelligence between the chimpanzee, which is the most intelligent, and the dog. And some of the scientists rank the dolphin even higher than the chimp.
When dolphins communicate they produce sounds by blowing air through the air passages they use for breathing. These passages lead to the blowhole, an opening at the top of the dolphin's head. The air passages and the blowhole have flaps of muscles that move to help make different sounds.
Because of the dolphins' very high intelligence, some scientists believe that man may eventually be able to communicate with the animals. An American physician by the name of John Lilly conducted communications experiments during the 1950s and 1960s, but he failed to develop a system of communication with the dolphins. Other research projects are continuing.
The bottle nosed dolphin is the star performer in many water snows. This dolphin can be trained to leap high into the air to grab a fish from its keeper's hand. And it can also be taught to jump through hoops and to fetch thrown sticks and balls.
The United States Navy is conducting research to learn more about the dolphins' use of echolocation. Echolocation is the dolphins' natural sonar system that helps them locate underwater objects. Dolphins locate objects by making sounds and then listening for echoes the sounds make when reflected by the object.
The sounds for echolocation are sent out of the dolphine's body through an organ called the melon. This organ lies within a bulge at the top of the animal's head.
There are chiefly two kinds of dolphins: The bottle nosed dolphin and the common dolphin. The bottle nosed type grows up to 12 feet long and weighs as much as 800 pounds while the common dolphin is about seven feet long and weighs only 150 pounds. The bottle nosed kind has from 80 to 88 teeth while the common variety has from 80 to 100.
Large schools of common dolphins often leap around ships in apparent joy. For hundreds of years, sailors have regarded these dolphins as a sign that their voyage will be smooth and happy.
Many people confuse the dolphin and the porpoise. Dolphins have snouts that form beaks but porpoises do not have beaks.
Dolphins are found in all of the oceans of the world and in some rivers. They feed mainly on fish and octopus like animals called squids. The animals are swift and very graceful swimmers. They can make sharp turns, sudden stops and high leaps as they swim.
Dolphins have keen eyesight and hearing and excellent sense of taste. But they have no sense of smell.