Birds can travel the world without any of the gizmos that humans depend on, and a new study suggests how: Our feathered friends might "see" Earth's magnetic field.
While other mechanisms are thought to help birds navigate, including magnetically sensitive cells within their beaks, their brain regions responsible for vision are in full gear during magnetic navigation, researchers said.
"If you look into the brain of a bird during magnetic compass orientation, only the visual system is highly active," said study co-author Henrik Mouritsen, a biologist at the University of Oldenburg in Germany, noting that most migratory birds do so at night. "Other regions of the brain are not, so birds could use vision to 'see' Earth's magnetism and orient themselves.
