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Magnetoception (or "magnetoreception") is the ability to detect changes in a magnetic field to perceive direction or altitude and has even been postulated as a method for animals to develop regional maps. It is most commonly observed in birds, though it has also been observed in many other animals including honeybees and turtles. Researchers have identified a probable sensor in pigeons: a small (dwarf), heavily innervated region of the skull, which contains biological magnetite. Humans have a similar magnetite deposit in the ethmoid bone of the nose, and there is some evidence this gives humans some magnetoception. ^{1citation needed} The eyes of the birds have been proposed to detect magnetic fields using the Zeno quantum effect. ². Magnetic fields are believed to affect the sleeping patterns of cows.³

Although there is no dispute that a magnetic sense exists in many avians (it is essential to the navigational abilities of migratory birds), it is a controversial and not well-understood phenomenon. Certain types of bacteria (magnetotactic bacteria) and fungi ⁴are also known to sense the flux direction, these contain organelles known as magnetosomes for this purpose. In bees, it has been observed that magnetite is embedded across the cellular membrane of a small group of neurons; the theory is that when the magnetite aligns with the Earth's magnetic field, induction causes a current to cross the membrane which depolarizes the cell.

See also

• Quantum biology

References

External links

• ABC Dr Karl - Magnetic Sixth Sense
• Evidence of a nonlinear human magnetic sense
• Modulation of spike frequencies by varying the ambient magnetic field and magnetite candidates in bees (Apis mellifera)
• The Physics and Neurobiology of Magnetoreception (Nature Reviews Neuroscience)