A new study shows that homing pigeons rely on iron-rich immune cells in their livers to sense Earth's magnetic field. The discovery offers a fresh explanation for how birds navigate over long distances, especially in poor weather.
Researchers at institutions including the University of Bonn and the Max Planck Institute of Animal Behavior found that macrophages in the liver accumulate iron and exhibit strong magnetic properties. These cells sit near nerve fibers, suggesting a pathway for magnetic signals to reach the brain.