Sense to Navigation that is magnetic

The researchers from the University of Munich in Germany claim that salmons, rainbow trout, turtles and many birds can migrate a thousand of miles at a time sensing the Earth's magnetic field.

A rainbow trout can navigate across distance, with the help detectors. These detectors have been identified as tiny compass needles existing in the nose of the rainbow trout.  

These researchers have identified cells that are present in the nasal passage of the trout that is very sensitive to the magnetism. They then placed these cells in the rotating magnetic field, a bunch of tiny iron rich crystals inside the cells called magnetic spun in synchrony with the field, turning the cells around with them. About one out of every 10,000 cells spun with the same frequency.  

Michael Winklhofer, who led the study said, "More importantly, we show for the first time that the internal compass needle has a strong connection to the plasma membrane [or outer membrane] of the cell, which is important to realise an immediate sensing process."

The researchers said, "The magnetic cells clearly meet the physical requirements for a magnetoreceptor capable of rapidly detecting small changes in Earth's magnetic field."

These findings were published in the Journal Proceedings of the National Academy of Sciences.

This study was based on age old research, which showed that magnetic fields affected the electrical activity of nerves that carried information from the fishes' noses. The researchers here didn't opt for the age old method of grinding up the tissues for analysis rather they gently isolated whole cells from the tissues and put them into petri dishes.

Kenneth Lohmann, a biology professor at the University of North Carolina who studies animals' magnetic sense, concluded saying, "The findings have ramifications beyond the realm of rainbow trout. If the authors are correct that the magnetite they have found is involved in detecting magnetic fields. This might have important implications for how other animals perceive magnetic fields. It is quite possible that similar magnetite crystals are involved in detecting magnetic fields in numerous animals.  It is also possible that there are two or more types of magnetoreceptors that evolved separately."