Cells scraped from the nasal passages of rainbow trout have been found to contain clumps of iron-rich crystals called magnetite, the same mineral used to create compass needles.
It is believed these crystals are sensitive enough to detect Earth’s weak magnetic field, equipping the trout (and possibly other migratory animals) with a kind of biological compass.
The discovery could have important technological applications, such as being used to develop miniaturised GPS systems or gene therapies that would restore sight, hearing or smell to people who have lost those senses.
Read more at University of Munich