The planet and its inhabitants are protected from the dangerous plasma and cosmic rays that are blasted off from the Sun by the magnetic field of the Earth. However, some animals use this magnetic field innovatively for navigating just like a GPS and also carry the capacity to turn it on and off very flexibly.
Researchers from Bowling Green State University in the US and the University of Western Ontario in Canada discovered a region of the brain which is called cluster N that is used by birds to detect and process the magnetic field of the Earth.
European Journal of Neuroscience published a study which stated that Cluster N gets activated only when the birds wish to migrate and probably engage in their magnetic compass.
Birds use magnetically sensitive proteins
In previous studies, it has been discovered that the birds like to use magnetically sensitive proteins called cryptochromes which are located in their retinas that enable their signalling and sensing functions, helping the birds in navigating the long distances they travel while migrating.
The team, headed by psychology PhD candidate Madeleine Brodbeck, studied white-throated sparrows and found that they were activating cluster N at night when they were motivated to migrate to other places and they were switching it off when they were resting during the day.
“This brain region is super important for activating the geomagnetic compass, especially for songbirds when they migrate at night. Almost all previous work on this specific brain function was done at one lab in Europe, so it was great to replicate it in a North American bird like the white-throated sparrow,” Brodbeck said.
The magnetic field, which is generated by molten iron’s flow in the inner core of the planet and extends out into space, remains invisible to humans.
However, in some animals that mechanism is present in their brain which helps them detect it when they travel long distances.
“If we want to understand bird migration or how other animals move from one place to another, we need to know how they do it. And more importantly, we need to know what we’re doing, as humans, that might influence them,” stated MacDougall-Shackleton.
According to the scientists, the birds don’t use the magnetic field normally, but instead, they pay attention to the stars and the Sun as cues too.
“This type of basic research informs us and lets us know the full suite of ways that animals perceive the world when they’re migrating and what we as humans need to do to minimize our impact,” MacDougall-Shackleton stated.