When we go somewhere on holiday, the satnav (usually) helps us. Migrating songbirds, however, routinely travel more than 10,000 kilometers – come rain or shine.
The tiny birds exhibit remarkable navigational precision. Even when they get lost or fly somewhere new, they always reach their destination.
It’s a mystery scientists have been trying to unravel for years. Now, growing evidence suggests the birds use the earth’s magnetic field as their compass.
The earth’s magnetic field, it is said, forms a grid of north-south and east-west lines, similar to our Cartesian coordinates.
Tests have shown that songbirds not only sense the earth’s magnetic field, but are capable of internalizing it, even altering their direction of take-off after undergoing a ‘virtual displacement’.