At Phys.org:
The team show for the first time that a molecule present in all living cells called flavin adenine dinucleotide (or FAD for short), can, at high enough amounts, impart magnetic sensitivity on a biological system.
Scientists already know that species such as the monarch butterfly, pigeon, turtle and other animals use the earth’s magnetic field to navigate over long distances. But the discovery could mean the biological molecules required to sense magnetic fields are present—to a greater or lesser extent—in all living things.
Co-lead researcher and neuroscientist Professor Richard Baines from The University of Manchester said, “How we sense the external world, from vision, hearing, through to touch, taste and smell, are well understood. But by contrast, which animals can sense and how they respond to a magnetic field remains unknown. This study has made significant advances in understanding how animals sense and respond to external magnetic fields—a very active and disputed field.”
To do so, the research team exploited the fruit fly (Drosophila melanogaster) to manipulate gene expression to test out their ideas. The fruit fly, although very different on the outside, contains a nervous system that works exactly the same way as ours and has been used in countless studies as a model to understand human biology.
– University of Manchester, February 22, 2023
The paper is open access.
Note: For all we know, humans have that sixth sense too. But we don’t pay much attention to fine points about anything beyond sight, sound, and touch.
You may also wish to read: Has the human sense of smell declined in recent millennia?
and
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