A new study suggests that some animals can detect the magnetic field of the Earth thanks to aggregates of proteins that prompt their nervous system allowing them to have a sense of direction. The paper is published in Nature Materials.
Aimed at finding the mechanism that governs the ability of some animals to navigate themselves, a team of scientists from Peking University, China, analysed a type of protein associated with magnetic fields found in the fruit fly. That was how they identified a ‘molecular compass’ comprising of an assemblage of small iron-binding protein MagR and flavoproteins known as cryptocromes. Apparently, the rod-shaped protein cluster helps animals to find their directions by acting on their nervous system.
When the proteins were examined in isolation in the lab, they would suddenly align when placed in the presence of a magnetic field. They were also strongly attracted to the researchers’ equipment that consisted of iron which then had to be replaced with plastic ones.
How does the MagR-cryptochrome cluster works in the animal body, then? It seems that when it detects changes in magnetic field, it signals nearby cells which then relay the information to the nervous system.
Lead researcher Can Xie explained in a statement to The Guardian that the “nanoscale biocompass” positions itself along the lines of geomagnetic field to “obtain navigation cues”. If this alignment changes, components of cells in the surroundings will transfer the information to the nervous system, thereby bringing about a sense of direction in the animal.
The clusters in question have also been detected in pigeons, and monarch butterflies. The researchers later found that the protein structures can form in the mole rat, and minke whale too. They were also eventually spotted in human cells, implying that humans might be endowed with a magnetic sense of direction, just not as strong as that of animals; as Xie explained, “human sense of direction is complicated”. But, he also added that it might constitute a potential explanation pertaining to people who are gifted with a good perception of direction.