Loggerhead turtles navigate long distances using geomagnetic fields.

• Loggerhead turtles can learn and remember the magnetic signature of an area, performing a ‘turtle dance’ when in a location associated with food.

• Researchers from the University of North Carolina at Chapel Hill housed juvenile sea turtles in tanks with magnetic signs related to specific geographical locations.

• The turtles were fed in only one of the two magnetic fields, demonstrating they can distinguish between them.

• The turtles’ internal’magnetic map’ relies on a separate mechanism to the ‘compass’, suggesting two distinct geomagnetic senses for navigation.

• The magnetic map sense of the turtle does not rely on this mechanism, while orientation behavior requiring the use of the magnetic compass was disrupted by radiofrequency oscillating magnetic fields.