The Porpoise of Echolocation

SCIENCE

Researchers have revealed how porpoises finely adjust the beams of sound they use to hunt. (BBC)

Use our resources to learn more about porpoises and dolphins here.

Teachers, scroll down for a quick list of key resources in our Teachers’ Toolkit.

Harbor porpoises like this one do not generate echolocation signals in the larynx, nor do they emit them through their mouth. Instead, they have specialized sound-producing structures, called phonic lips, located high in the blowhole. Phonic lips! Photograph by AVampire Tear, courtesy Wikimedia. CC-BY-SA-3.0

Harbor porpoises like this one do not generate echolocation signals in the larynx, nor do they emit them through their mouth. Instead, they have specialized sound-producing structures, called phonic lips, located high in the blowhole. Phonic lips!
Photograph by AVampire Tear, courtesy Wikimedia. CC-BY-SA-3.0

Discussion Ideas

  • Researchers profiled in the BBC article studied the way porpoises use echolocation to hunt fish. What is echolocation?
    • Echolocation is the ability of some animals to emit sounds and determine an object’s distance by the time it takes for those sounds to echo back to the animal. Sometimes, echolocation is called “biosonar.”

 

  • According to the BBC article, the porpoises studied used two sounds in their echolocation technique. What are the two sounds?
    • clicking. When doing a broad search for food, porpoises use an exploratory click to get a general idea of where fish are.
    • buzzing. After a fish or school of fish have been “spotted” with the click, porpoises use a high-frequency buzz to elicit a continuous echo from the fish they are pursuing.

 

  • The BBC article says the porpoise echolocation technique is “like a adjusting a flashlight.” How?
    • Porpoises can switch from a narrow, penetrating burst of sound to a broad, wide beam of sound. “If you were trying to find your car in a car park, you could use a narrow beam over a long distance and still see a lot,” says one scientist. “But when you’re trying to get your keys into the car, you would switch to a wider beam.”

 

  • Can you think of any other animals that use echolocation to hunt prey?
    • Porpoises’ cousins, dolphins and toothed whales, also use echolocation.
    • Some birds (oilbirds and switftlets) use a type of echolocation.
    • A few terrestrial mammals, shrews and tenrecs (so cute!), use echolocation.
    • The world’s most famous echolocators are probably bats! Take a look at our terrific illustration of a bat using echolocation to zero in on a tasty moth.

Illustration by National Geographic

 

TEACHERS’ TOOLKIT

BBC: Porpoises, whales and dolphins use ‘sound searchlights’

Nat Geo: Is it a Porpoise or a Dolphin?

(extra credit!) eLife: Range-dependent flexibility in the acoustic field of view of echolocating porpoises (Phocoena phocoena)

2 responses to “The Porpoise of Echolocation

  1. Pingback: Whale’s Goes Native in the Dolphin Pool | Nat Geo Education Blog·

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