Today I found a short, interesting article from Live Science. It’s reasonably well-known that scientists believe birds can detect the Earth’s magnetic field. Last year, a study was released suggesting a pigeon’s ability to sense magnetic fields originates from neurons in their inner ears. Recently researchers have discovered that pigeons have microscopic irons balls in their inner ears. The scientists hypothesize that these iron pockets could be the key to understanding how birds are able to detect magnetic fields. The purpose of these “iron-imbued neurons” is still a mystery, but they are the best lead for understanding the pigeon’s amazing sensory biology. Another possible function of the iron clusters would be that they help birds hear low-frequency noises. Not only were these iron balls found in pigeons, they appeared in every bird species surveyed.
I think this is really interesting research. If the scientists are correct about the function of the iron balls, I suspect the neurology of other magnetic field receptive animals (i.e sea turtles) will be under evaluation next. From another post I did about animal sixth senses, the article said pigeons have iron-containing structures in their beaks as well. The iron structures in their beaks are supposed to allow pigeons to sense spatial orientation and identify their geographic position. I’m not quite sure how different these beak iron structures are from the ear iron structures, but it seems obvious that iron structures are important for magnetoreception. And pigeons sure seem to have a lot of them!