diff --git a/sijapi/data/article.md b/sijapi/data/article.md new file mode 100644 index 0000000..d5a439a --- /dev/null +++ b/sijapi/data/article.md @@ -0,0 +1,72 @@ +# Watch turtles ‘dance’ when a magnetic field signals a meal + +*By Frances Vinall* + +*Published: 2025-02-12* + + + +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. + +Advertisement + +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.” + +Advertisement + +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.