Marine Biology
dolphins use sonar

How Dolphins Communicate



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dolphins use sonar
Effie Moore Salem's image for:
"How Dolphins Communicate"
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Dolphins use echolocation, or sound waves, to communicate with others members of their group, to spy on their enemies, to tease and intrigue mates and to do lots of other fascinating things to captivate visitors. Dolphins are smart and they have a large vocabulary of sounds, clicks, moans, shrieks, scrapes, whistles and possibly all manner of combination sounds they learn in their developmental dolphin schools.  

While the above statements may read like fiction, scientific observations show they do imitate sounds they’ve learned from their environment:  motorboat motors whizzing, the voice of humans that coo to them, and other weird and unusual sounds. Watching them maneuver and show off is fun for spectators but to the dolphin their sonar is serious business. It enables them to stay clear of predators and to rush to the aid of offspring, to warn others of danger, and in general it’s their most used communicative tool.

How sonar words

Sonar or sound waves are echoes. They’re made by sounds bouncing off solid objects and when done underwater the magnification is greater than when done in air. Although each creature, whether air born or underwater has specialized DNA blueprinted toward their specific sonar needs.  Dolphins appears to have a set of sounds not totally unlike that of humans and that, along with their docility and their show off nature, makes them especially intriguing to humans.

Once the sounds are sent out they bounce off and are sent back and this tells the sender of what objects are nearby and how dangerous or how likely there’s food for fuel nearby or in hearing distance.  

Active and passive sonar

Of the two types of sonar, active sonar sends out sounds and if there’s equipment—man made transducers or other creatures such as dolphin to dolphin, dolphin to another sea creature—then the sound is recorded or heard and responded to with the appropriate reaction. Passive is sonar heard and decoded but not answered. An example of that would be the sound sea creatures hear when boats and large cargo sail by. From experience they have learned to get out of the way, dive deeper or swim into freer waters. To further define, active sonar is participatory; passive is listening in and acting according to mission.  

Dolphins and sonar

Bio-sonar characterizes the specialized sonar of dolphins. Their blueprint for sensitive hearing and detection is fine-tuned enabling them to survive in a dangerous environment. These sounds are made through their nasal passages and are sent through their forehead and processed into a beam before being emitted into the water. As the sound travels through the water it hits objects and echoes back the type of sound made. The sound is absorbed through the jaw. A wad of fat in the jaw transmits the echo to the inner ear and the sound is then passed on via a neurological passageway to the brain for interpretation.

Scientist study dolphins and have learned that their DNA closely resembles that of humans. With that relatively new information they’re searching for other likenesses that will shed light on many as yet unanswered questions.


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ARTICLE SOURCES AND CITATIONS
  • InfoBoxCallToAction ActionArrowhttp://octopus.gma.org/marinemammals/communication.html
  • InfoBoxCallToAction ActionArrowhttp://www.exploratorium.edu/theworld/sonar/sonar.html