Diving in the World of Biosonar
Channel: American Scientist
Date: 2015-01-30

Some animals use additional senses to see the world differently than humans. One such sense is called biological sonar. Biological sonar is when an animal releases a series of sounds that may not be audible to humans and waits for the echoes to return. Toothed whales, which includes porpoises, are one of two types of animals that use biological sonar to sense and navigate through their environment (the other being bats).

These clicks are one of the most high-pitched signals produced by any animal. The time between the released clicks and the returning echo tells the porpoise the distance and location of the nearby object.

The porpoise’s way of sensing its surroundings is disrupted by noises emitted by pile driving, seismic explosions, and ships, just to name a few. Understanding how they detect their underwater world can help protect them.

To learn more about the research behind this fascinating ability, read the article titled, “The Acoustic World of Harbor Porpoises” in the January–February 2015 issue of American Scientist (restricted to American Scientist subscribers and Sigma Xi members): 

http://www.americanscientist.org/issues/feature/2015/1/the-acoustic-world-of-harbor-porpoises

American Scientist is the illustrative, award-winning magazine of Sigma Xi, The Scientific Research Society and is your source of science, technology and engineering news and features since 1913! Visit our website at http://www.americanscientist.org.

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Image and Audio Attributions:

Background Music: Lost Radiance, "Far Away," http://freemusicarchive.org/music/Lost_Radiance/.

"Principle of a sonar or radar distance measurement" by Georg Wiora (Dr. Schorsch) (Self drawn with Inkscape) [GFDL (http://www.gnu.org/copyleft/fdl.html), CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0/) or CC BY-SA 2.5 (http://creativecommons.org/licenses/by-sa/2.5)], via Wikimedia Commons

"Echolocating Bats Use a Nearly Time Optimal Strategy to Intercept Prey" from Ghose K, Horiuchi T, Krishnaprasad P, Moss C. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1436025/?tool=pmcentrez PLOS Biology. DOI:10.1371/journal.pbio.0040108. PMID 16605303. PMC: 1436025.

"Example of hazel-green eyes. Photo taken by myself of my own eyes. Laurin Guadiana" by Laurinemily at en.wikipedia [CC BY-SA 2.5 (http://creativecommons.org/licenses/by-sa/2.5)], from Wikimedia Commons

"The Harbor Porpoise - Kerteminde Fjordcenter - Denmark" by Erik Christensen (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons

"Drina river bottom covered in rocks and gravel near Šćepan Polje. Upper course of the river." by Liquid Art (Own work) [CC BY-SA 4.0 (http://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons

"Pile driving operations in the Port of Tampa, Florida, United States." by JillFine at en.wikipedia [Public domain], from Wikimedia Commons

Ocean map, Natural Earth II at www.shadedrelief.com/natural2/index.html

Rumble sound effects by Sandyrb on https://www.freesound.org/people/sandyrb/sounds/84347/.


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