The mechanism of animal magnetoreception

Although humans do not sense the earth’s magnetic field (geomagnetic field) in daily lives, the magnetoreception ability has been demonstrated in a variety of species, including birds, reptiles, amphibians, fish, insects, and even bacteria. Animals, in particular, are thought to use the geomagnetic field for navigation during migration or homing. For description of animals’ magneto-responsibility, two types of mechanisms were proposed:“magnetite mechanisms”and“radical pair mechanisms”. The magnetite mechanism is a mechanical method that utilizes tiny magnetic particles, while the radical pair mechanism is a chemical method that utilizes light energy. Although the details of these mechanisms are still unknown, the study for elucidation of each mechanism have been proceeding in bacteria and birds, respectively. In this review, we introduce the organisms which possess the magnetoreception ability and the differences in the characteristics of the two magnetoreception mechanisms described above. In addition, our own research related to radical pair mechanisms and recent research trends is presented.