Dolphins, it seems, can perceive the Earth’s magnetic fields.
Some researchers wondered if these intelligent cetaceans had a magnetic sense because they’ve found magnetite (magnetized iron oxide particles) in the brain membranes of dolphins. Also, it appears that dolphin strandings might be that magnetic GPS gone awry. The website OceanLink explains:
More precisely the theory states that dolphins are following disruptions in the magnetic field as navigation corridors. The strandings occur in areas of low magnetic field density where the navigation corridors intersect land at right angles. The theory states that dolphins follow these magnetic corridors and plough onto land thinking it is where they want to go. In areas where the corridors followed the coastline fewer strandings occurred.
But scientists weren’t sure that these shaky lines of evidence added up to proof of magnetic sensing. So a group of researchers from France decided to put the theory to the test. When the team put magnetized and unmagnetized objects in a pool, the dolphins swam faster toward the magnetized ones. Both kinds of objects were the same shape and density, so the dolphins weren’t distinguishing between them using their other sense, echolocation.
The work, published in the journal Naturweissenschaften, shows that dolphins can indeed feel magnetic fields.
“Inside the ocean, the magnetic field would be a very good cue to navigate,” lead researcher and animal behavior expert Dorothee Kramers from the University of Rennes told Livescience.com’s Tanya Lewis. “It seems quite plausible for dolphins to have a magnetic sense.”
Dolphins have a number of other special sensory talents—adaptations that allow them to navigate through their watery world. For example, their sensitive hearing came through a number of physical changes, according to Dolphinsworld.com:
They are able to hear frequencies that are least 10 times what the best adult hearing can offer. The ears are very small openings but don’t let that fool you. They are also able to hear well under the water and it is due to them doing so through the lower jaw rather than only using the ears. The lower jaw is able to conduct sound to the middle ear through a cavity that is filled with fat.
Their echolocation ability also means they can “see” things we can’t, such as pregnant women’s (and dolphins’) fetuses.
Still, the magnets used in the study were several times stronger than the magnetic field of the Earth, so more work needs to be done for researchers to be sure of this discovery. (Other research on magnetic senses in animals hasn’t always born out.) But in any case, dolphins will continue to be super cool. It is definitely not wrong to have them as your favorite animal.
Photo via LaPrimaDonna/Flickr (CC BY 2.0)