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+# Watch turtles ‘dance’ when a magnetic field signals a meal
+
+*By Frances Vinall*
+
+*Published: 2025-02-12*
+
+![Article Image](https://www.washingtonpost.com/wp-apps/imrs.php?src=https://d1i4t8bqe7zgj6.cloudfront.net/02-12-2025/t_9bc85bf333404f078852254febc003f2_name_turtle_1.png&w=1440)
+
+Scientists have discovered a new reason for turtles to dance for joy: Loggerhead
+sea turtles seem able to discern and remember magnetic field signatures, which
+could help them find food. The Earth’s magnetic field is detected by species
+across the animal kingdom — there are even suggestions that some humans
+unknowingly sense it — using an ability scientists call magnetoreception. But
+how animals are able to do this, and how different species use the magnetic
+field, remain open questions under investigation.
+
+Now, in a study published Wednesday in the journal Nature, researchers from the
+University of North Carolina at Chapel Hill report that when turtles are placed
+inside a magnetic field they have been trained to associate with food, they
+“dance” in response.
+
+“Sea turtles are renowned for their long-distance migrations and extraordinary
+navigational abilities,” wrote the authors, who include researchers from the
+university’s Lohmann Lab, which specializes in studying animal navigation and
+sensory biology.
+
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+
+Baby sea turtles seem to respond to information present in the magnetic field
+from the very beginning of their lives, they added.
+
+The researchers studied turtles in two laboratory environments with different
+magnetic signatures, feeding them in one and not in the other. When the
+loggerheads were placed in an environment up to four months later with the same
+magnetic signature as the one that they had learned to associate with meals,
+scientists reported, they were much more likely to do the “turtle dance,”
+indicating that they expected to be fed.
+
+They would tilt, open their mouths, flap their front flippers and spin in place
+in the water.
+
+“The results provide strong evidence that loggerhead turtles can learn the
+magnetic signatures of specific geographical areas,” the authors wrote. “Such an
+ability has, to our knowledge, never before been demonstrated in any animal.”
+
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+
+Earth’s magnetic field is generated by the spinning ball of molten iron at the
+planet’s center. It performs a variety of important functions, including acting
+as a shield against solar winds.
+
+Several migratory species, including birds and sharks, are believed to use a
+compass-like sense to navigate with its help. While scientists are still
+researching how it affects animals’ behaviors, it influences everything from how
+migratory birds find their destination to the fact that dogs usually defecate
+while standing along a north-south axis.
+
+While sea turtles may have this compass capacity as well, the sensory ability
+loggerheads demonstrated in the lab was distinct, the researchers said. The
+memorized signatures appear to help these turtles form a “map” of the magnetic
+field.
+
+Chemist and biophysicist Jonathan Woodward, a professor of the Graduate School
+of Arts and Sciences at the University of Tokyo who was not involved in the
+Nature study, said in an email that it was an “important study” that
+demonstrates how “turtles specifically use both the intensity and the
+inclination of the geomagnetic field to identify target locations and store and
+reuse this information over long periods of time.”
+
+Woodward, who studies the molecular basis of magnetoreception, added that there
+has been a long-standing debate over how animals might use the magnetic field to
+traverse the ocean, land and skies and map them.