Scientists have been interested in magnetoreception, the ability of living organisms to perceive magnetic fields, for the quite some time. Ever since its discovery, numerous different species have been identified which possess the ability to sense direction and navigate using Earth’s magnetic field.
Sea turtles, honeybees, spiny lobsters, and several migratory birds all possess a built-in magnetic compass that enables them to perceive and utilize information from Earth’s magnetic field. What’s even more interesting is that our planet’s magnetism can even act as a map for some animals.
New research by Dorothee Kremers and her colleagues at the Ethos unit of the Université de Rennes in France provides experimental behavioral proof that dolphins are among the animals that are magnetoreceptive. Various observations have suggested that this was the case, but there was previously no evidence to back up these assumptions.
In order to investigate further, the team of French researchers examined the behavior of six captive bottlenose dolphins that were being kept at the Planète Sauvage safari park in France. The researchers recorded the response of the dolphins to the presentation of two devices that were contained within boxes.
One of the devices was strongly magnetized, and the other was a demagnetized control. The blocks were identical in shape and destiny and were therefore indistinguishable by echolocation. During the experiments, the dolphins were allowed to swim around the pool as they pleased.
What the researchers found was that the dolphins were much quicker to approach the magnetized block than the control block, although they did not interact differently with the two barrels, suggesting that the dolphins may have been more intrigued by the magnetized block, rather than physically drawn to it.
“Dolphins are able to discriminate between objects based on their magnetic properties, which is a prerequisite for magnetoreception-based navigation,” lead author of the recently published Naturwissenschaften study Dorothee Kremers said in a news-release. “Our results provide new, experimentally obtained evidence that cetaceans have a magnetic sense, and should therefore be added to the list of magnetosensitive species.”
Read more about the story at Springer.