Birds migration is the journey that birds travel due to the absence of food or the change in weather, in order to travel to their own habitats. It is known that some birds use the sun as a compass in their navigation’s, others depend for their migration on detecting magnetic fields.
Scientists of University of Oxford along with the scientists of National University of Singapore has reached to a new theory that the birds can see the force of magnetism, that are invisible for us. The concept is that when the birds eye absorb the light photon, a molecule in the eye kick an electron for a distance of few nanometers. While the electron return to its place it creates an electric dipole field which increases the bird’s sight.
That’s the kind of evolutionary trick that’s truly amazing. As worded in an Oxford press release: “According to the new model, when a photon of light from the Sun is absorbed by a special molecule in the bird’s eye, it can cause an electron to be kicked from its normal state into an alternative location a few nanometres away. Until the electron eventually relaxes back, it creates an ‘electric dipole field’ which can augment the bird’s vision – for example altering colours or brightness.”
There are many of these molecules with many orientations spread throughout the eye, the researchers presume, so as the bird moves its head the patterns in its field of vision shift, offering crucial information about the Earth’s magnetic field and navigational direction.
The researchers also note that while this sounds like some kind of higher vision mechanism, it’s really the kind of thing that could evolve quite easily. It doesn’t require the development of some new sensory organ but rather just piggybacks on normal vision. If some birds developed this trait via genetic mutation or some other avenue, it would give them a distinct evolutionary advantage over their peers when it comes to migration. And it wouldn’t take long, in evolutionary terms, for something like this to manifest itself across populations.