A PROTEIN that detects blue light also helps fruit flies tune into the Earth’s magnetic field. Sensing this weak field is crucial for the homing and migration abilities of many animals.
Researchers suspected that proteins known as cryptochromes detect magnetic fields, perhaps by making charged molecules – called free radicals – when they’re struck by blue light. The number of free radicals formed may depend on the strength of the field, indicating the creature’s latitude. But evidence from migratory warblers and salamanders has so far only hinted at this connection.
Now a team led by Robert Gegear and Steven Reppert of the…
