Abstract: Many living things have an internal compass which can get the information of orientation from geomagnetism as well as people using a real compass. We start from the generation of magnetism, and then introduce the property of geomagnetism and biological magnetic induction. Birds having migratory behavior are the kinds of Vertebrata which has firstly been found to have a remarkable ability of perceiving the Earth’s magnetic field. Research results show that, migratory birds can perceive and remember the magnetic features of the place they have ever been and get route direction from them. In addition, some of the avian compass
have a dependence on blue light, and may be disrupted by anomalous magnetic field. Such phenomenon can be explained by two prevalent modes of magneto-reception, the magnetite-based magneto-reception and chemical magneto-reception, either or both of them could be found in organisms that have the so-called sixth sensation. Many other creatures, including human beings, have the same kind of magneto-receptors as well. However, not all of them use the sixth sensation as a visual or auditory aid, during the long term evolution this ability may be disappeared or replaced by something else. This review also focuses on progress in biological magnetic phenomena and biological perspective of hypo-magnetic field; they are expected to elicit more amazing results.

Key words: geomagnetism, migratory bird, internal compass, the magnetite-based magneto-reception, chemical magnetoreception, hypo-magnetic field