Scientists have long wondered how many animals are able to essentially detect Earth’s magnetic fields, and they might finally have their answer. Within the cells of fruit flies, scientists from China say that they have located a complex of proteins that the flies use to align with the magnetic field of Earth. The findings were made by a team that was led by Peking University biophysicist Xie Can.
This “biocompass” has long been hypothesized in many animal species, including humans. This could explain why animals such as birds and insects are seemingly able to detect and respond to magnetic forces. Scientists believe that animals use this natural compass to determine the direction they should take at certain periods in the year.
However, scientists still have some work to do. It has not yet been shown how the protein complex actually behaves as a compass, and it is still unknown how it is able to detect magnetism. Some scientists have suspected that the study could be totally off the mark.
The ability to use Earth’s magnetic forces to navigate oneself is known as “magneto-reception”. Some researchers have said that magneto-reception is linked to magnetically-sensitive proteins that are called “cryptochromes”. It has been found that fruit flies without the cryptochromes proteins cannot properly sense magnetic fields.
However, since cryptochrome proteins cannot differentiate between north and south, they cannot act as a compass alone. Some scientists have speculated that iron-based proteins found within the animals could play a role, but this has not been proven.
The Chinese scientists are claiming that they found a protein in the fruit flies that both interacts with the cryptochromes and binds to iron. The protein is called CG8198. When it works with the cryptochromes, it essentially acts as a compass, at least in theory. The CG8198 protein has already been shown to affect the day-night cycle of the fruit flies.
When examined using an ultra-powerful electron microscope, the scientists say that they saw these protein rods orient themselves in the same way as the needle of a compass. Since then, the CG8198 protein has been nicknamed MagR, or magnetic receptor.
Additionally, the study also opens the door for scientists to use magnetic fields to control cells within the brain. Scientists have already used light-sensing proteins to manipulate the brain, but this requires direct access. Magnetic forces could be used to control the brain from the outside, without access.
In fact, neuroscientist from Tsinghua University in Beijing Zhang Sheng-jia said earlier this year in September that he already used the biocompass within earthworms to manipulate the neurons within their brains. However, Zhang’s research was based on that of Xie’s, and Xie has complained that Zhang’s early publication was in violation of an agreement that was made between them. Zhang has since been fired from Tsinghua University, a move that he is currently disputing.
Still, many scientists are skeptical that the findings from Xie can be applied to other organisms. Just because they worked in fruit flies does not mean that other animals use the same method of detecting magnetism.
For now, scientists will continue to conduct research in order to better understand how animals are able to sense direction. Regardless of the findings, there’s no denying the fact that animals have some pretty useful techniques in their brains.