Homing pigeons are known for their uncanny ability to find their way home – navigating complex and changing landscapes. In fact, they do th...
Homing pigeons are known for their uncanny ability to find their way home – navigating complex and changing landscapes. In fact, they do this so well they were used as a source of secure communication more than 2,000 years ago.
Julius Caesar reportedly sent news of his conquest of Gaul back to Rome via pigeons, as did Napoleon Bonaparte following his defeat by England in the 1815 Battle of Waterloo.
We know pigeons use visual cues and can navigate based on landmarks along known travel routes. We also know they have a magnetic sense called “magnetoreception” which lets them navigate using Earth’s magnetic field.
But we do not know exactly how they (and other species) do this. In research published recently in the Proceedings of National Academy of Sciences, my colleagues and I tested a theory that attempts to link magnetoreception in homing pigeons with tiny lumps of iron-rich material found in their inner ears.
By using a new kind of magnetic microscope, we confirmed this is not the case. But the technology has opened the door for us to investigate the phenomenon in several other species.
Current hypotheses
Scientists have spent decades exploring the possible mechanisms for magnetoreception. There are currently two mainstream theories.
The first is a vision-based “free-radical pair” model. Homing pigeons and other migratory birds have proteins...
