Some species of shark are able to swim thousands of kilometers from feeding grounds and return to them each year, according to science.
The sharks possess an amazing ability: they can find your way back to the feeding grounds every year even though thousands of kilometers are away from them.
According to one study, this is because sharks are endowed with a superior navigation tool: they orient themselves using the Earth’s magnetic field.
However, they are not the only animals that have this species of Internal GPS. The birds, the Whales and lots other species also use this innate sixth sense to chart their migrations.
Florida State University biologist and co-author of the study published in Current Biology, Bryan Keller believes it is the best explanation for understand why sharks are capable of such distant migratory journeys and return to the food fishing grounds. Every year.
Sharks create a kind of map of the Earth’s magnetic field
More than 3,000 kilometers below the Earth’s surface, the iron that surrounds the outer core of the planet generates a magnetic field extending from the inside to the outer space that surrounds the earth. It fulfills a fundamental function: protect life on the surface of solar radiation.
Now, the direction in which the electromagnetic energy flows, and the strength of the resulting protective layer depend on where the individual or animal is on the planet. Animals that use the magnetic field to orient themselves in their migrations detect differences between force intensity and field flow to find out where they are and where they want to go.
Scientists have long suspected that sharks navigate using the Earth’s magnetic field. All animals can feel these fields. However, until Keller’s study, it had not been possible to confirm the general hypothesis.
“This means that sharks have the ability to remember a specific location and return to it,” explained the biologist in statements to Business Insider.
To prove their hypothesis, the team caught 20 sharks off the coast of Florida traveling to the Gulf of Mexico and took the animals to a tank 3 by 3 meters in which generated a magnetic field in a small area.
Subsequently, the team introduced lightweight variations in magnetic field generated to mimic sea conditions where the sharks in the study had been caught. They let the sharks act the same way they would in the wild, and indeed the ‘guinea pigs’ they tried to reorient themselves naturally and they swam in the direction that for them led to the Florida coast inside the tank.
The team went one step further, and also recreated the conditions of the Gulf of Mexico, and there the animals showed no signs of reorientation, so the research team assumes in their study that the sharks considered they were in the right place.
Sharks are not the only ones: many animals use the magnetic field to orient themselves
How could a great white shark, for example, migrate from South Africa to Australia, a distance of more than 12,000 miles, and return to the same area nine months later if not using the Earth’s magnetic fields? This is the basis on which Keller justifies the conclusion of his study.
“On the way to Australia, the animal showed an incredibly straight swim path,” says Keller. “Given that the magnetic field is perhaps the only constant and ubiquitous signal available to these migratory sharks, it makes sense to think that magnetic-based navigation is what gives them that ease of navigation.”
The biologist himself acknowledges that there are other navigation signs in nature known, as currents and tides, but he considers the action of the magnetic field more useful for sharks since it is a more constant or fixed aid in their natural navigation systems.
For now, biologists are not sure how sharks detect this field. In 2017, a study suggested that magnetic receptors in animals are probably located in the nose.
Scientists have observed this ability to detect magnetic fields and use them as a guide for their orientation in bacteria, algae, mud snails, lobsters, eels, manta rays, bees, honey, mole rats, newts, birds, as well as in fish like tuna and salmon, or in mammals like dolphins and whales.
In the case of the Marine turtles They use these magnetic signals for breeding: they carry their eggs to the beaches where they were born, thousands of kilometers from their later habitat.
Dogs can find their way home thanks to their impressive sense of smell and that they orient themselves using magnetic forces, according to a study.
This article was published in Business Insider Spain.