USING MAGNETIC FIELDS FOR ORIENTATION

Magnetoreception is a sense which allows organisms to detect magnetic fields and use them to align themselves. This sensory system is used by a range of animals for orientation and navigation. The idea that animals perceive earth’s magnetic field was once dismissed as impossible by physicists and biologists – they argued that it is much too weak for an organism to detect and there are no biological mechanisms capable of converting magnetic-field information into electrical signals used by the nervous system. Over time, however, evidence showed that animals can perceive magnetic fields. It is now clear that many species utilise information in earth’s magnetic field to guide their movements over distances both large and small. What has remained mysterious is exactly how they do this.

South African Quantum Physicists, Betony Adams and Francesco Petruccione, share some current theories, including how birds use magnetoreception to navigate during long-distance migration. This article first appeared in ‘Quest: Science for South Africa’ in January 2022.