Sharks use Earth’s magnetic field like GPS to navigate the oceans

How do sharks navigate the deep and dark world under the sea? Scientists now say they have the first evidence showing sharks use Earth’s magnetic field like GPS to move through the oceans and oceans. There are no “street lights” or physical barriers to guide them on their long-distance journeys and migrations. Yet they seem to identify and reach their destination thousands of miles precisely. Saying that sailing in three-dimensional oceans is one of evolution’s most astonishing feats, the researchers say it’s likely that sharks use their sensory organs to read Earth’s magnetic field such as maps or atlases.

Published in the latest issue of the journal Current Biology, the research tested a previously unverified theory that sharks use magnetic fields to navigate. For this, they focused on smaller sharks. Researchers are also trying to identify shark species that are known to return to specific locations each year. Save Our Seas Foundation project leader Bryan Keller, who was conducting research in a Florida laboratory, decided to study the wild head bonnethead (Sphyrna tiburo).

Keller Told SciTechDaily stated that the behavior of bonnetheads who “come home” every year has shown that they know where their home is. Keller and his colleagues used a magnetic displacement experiment to test 20 tiny hood heads.

They make devices that create special magnetic conditions that sharks might encounter in the ocean. Their effort is to see the navigation orientation of these sharks as a function of the strength and angle of the artificial magnetic field. If they were oriented in some way, the researchers predicted it would be an indication that they were using a magnetic field to find their position on Earth and determine their swimming direction.

The researchers used a different magnetic field. Bonnetheads don’t get much of a response to magnetic fields that mimic their native region or that they would find along their normal return path. But when exposed to a magnetic field 600 km south of their way to their home, they constantly try to aim and orient themselves north with their heads.

The researchers believe their findings will provide insight into how sharks migrate across vast oceans and how marine technology used by humans can affect them.

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