Bird Migration: The Maps Of The Mind

Adult birds develop navigational maps inside them to help them travel to faraway lands. How this happens is still a mystery and various theories are being considered: infra-sound, smells, and gravity variations.

A theory gathering some evidence is that the earth’s magnetic field forms a grid that is followed by the birds.

Studies done on the reed warbler (Acrocephalus scirpaceus), a Eurasian migratory bird, provide clear evidence of the magnetic field.