Humans can only use five senses to perceive the world around us. In the animal world, many are also capable of detecting the magnetic field of the Earth. Researchers reported new conclusions on magnetic detection in birds and recently presented their research. Scientists from the University of Oldenburg, Germany and Oxford in the United Kingdom have gathered evidence suggesting that magnetic detection of migratory birds such as European robins is based on a specific light-sensitive protein.
In their research, the team has demonstrated a protein called Cryptochrome 4 found in the bird’s retina is sensitive to magnetic fields and could be the magnetic sensor that scientists are looking for. The researchers of the project extracted the genetic code of Cryptochrome 4 found in European migratory robins at night and were first able to produce the photoactive molecule in large quantities with the help of bacterial cell cultures.
Another team of researchers has used a range of magnetic resonance and optical spectroscopy techniques to study the protein and demonstrate its sensitivity to magnetic fields. The researchers on the project may also discern the mechanism that gives rise to the sensitivity, which is called another important step. The electrons capable of moving in the molecule after activation of blue light play a critical role.
Proteins, like cryptochrome, have amino acid chains and Robin Cryptochrome 4 have 527. The researchers of the project found that four of these 527 amino acids called tryptophanes are essential for the magnetic properties of the molecule. The calculations showed that the electrons jump from a tryptophan to another, generating something called magnetically sensitive radical pairs. The experiments have shown that the radical pairs generated are essential for explaining the observed magnetic field effects.
The team estimates that the results they found are important because they show for the first time that the visual molecule of the visual device of a migratory bird is sensitive to magnetic fields. However, the team is clear that they have not found the definitive proof that Cryptochrome 4 is the magnetic sensor that the team is looking for.
