Scientists have long been puzzled over the mechanism that enables birds and fish to return to their nests and home waters without fail.
But according to Hiroshima University President Yasuo Harada, an experiment conducted earlier this week proves his theory that traces of iron found in the otolith organs located in the inner ear of birds enables them to find their way back to their nests.
Otolith organs give animals the sense of horizontal and vertical. While animals all have two types of otolith organs, fish, birds and amphibians have a third version that helps them sense their position in the air or in water.
In March, Harada, who specializes in otolaryngology, detailed his theory that birds and fish use these iron traces in this third organ as a compass to sense terrestrial magnetism and thus get their bearings.