‘Pigeon-nav’ linked to built-in magnetic compass that humans also have – new report
A new study published in the journal Nature Materials has discovered magnetic proteins in the eyes of animals that, together with sunlight, act as a compass in the Earth’s magnetic field. Even more fascinating is that researchers have discovered the same proteins also exist in human eyes.
The proteins, which run from the retina nerve in the eye to the brain, form rod-shaped complexes that orientate in a north to south direction in a magnetic field - just like a built-in compass.
Pigeons are known to be exceptional navigators, covering enormous distances to reach their exact desired location. But according to the study, they are not the only ones producing these magnetic proteins: fruit flies, monarch butterflies, minke whales, and naked mole-rats all seem to have what it takes to navigate using a magnetic field. That’s not to mention humans - although we seem to have the proteins in lesser quantities.
Dr Can Xie, a molecular biologist at Peking University in China who led the research, explains that the proteins act just like a compass needle and send information to the nervous system.
This “needle” is so magnetic that the researchers had to develop special plastic tools to carry out their work.
Similar research from Texas this summer showed a magnetic field sensor in a worm, adding to evidence that certain animals use the planet’s magnetic field to navigate. However, scientist’s haven’t been able to prove exactly how.
READ MORE Worm’s-eye view: Scientists find first-ever animal sensor detecting Earth's magnetic field
“The bio-compass model we present here may serve as a step towards fully uncovering the molecular mechanism of animal navigation and magnetoreception,” Dr Can Xie said.
When it comes to humans, he believes that “the existence of a human magnetic sense is controversial, but geomagnetic fields are thought to affect the light sensitivity of the human visual system.”
