An alternative explanation for why Green Shield units work on rodents?
New Scientist is reporting that although certain mammals are able to detect magnetic fields, where the sense originates was not known. Now, the organ that houses magnetic sensors in Ansell’s mole rat (Fukomys anselli) has been identified. This species of mole rat, known for digging long, subterranean tunnels, has poor eyesight and tiny – but structurally intact – eyes. Mole rats were placed in an arena in which magnetic fields could be used to artificially change the direction of magnetic north. They found that the mole rats with intact eyes always built their nests in the magnetic south-eastern quadrant of the arena. Researchers believe the eyes may contain magnetite, a magnetic iron ore, and we think one explanation of the way this works is that the slight changes in the magnetite’s movement to align with the Earth’s magnetic field allows the mole rat to detect the field and orient themselves. If magnetite is also present in other rodents, then the Green Shield unit’s field may disturb their sense of orientation, increasing their stress levels, which inclines them to leave the area.
