Do we have biological internal compass

Birds have magneto-reception model called Cryptochrome

When migrating, the birds depend on their sense to determine the right path. Wherever they are come from, they never get lost even though the trip takes thousands of kilometers. Whatever the disaster comes including winds, rainy or sometimes they stop in certain places, they always arrive at the same place every year. What makes they always correct?

It is not only birds that have the ability of sensing the right path. Whales, butterflies, and ducks are some of the animals that has ability to determine the north point. If those animals use their instinctive sense for doing migration, sea turtles use it for remembering the same place in order to lay their eggs.
The ability of animals can point the north direction is happened because they have internal compass built-in inside their body. Scientists called this ability as magneto-reception as the animals use their receptor in sensing the magnetic field created by the earth. This ability is not only about pointing the north pole, but also the ability of memorizing the departure and arrival places. For instance, the pigeon birds which are classified as pet in certain society are able to memorize where exactly their nest in the first time. so, everywhere they fly, they always go back to their home.

Magneto-receptors in Human
If we compare to human, actually we also have the ability of remembering the direction. For long time ago, scientists have been wondering if human also the same ability which can determine where the north pole is. In 1980s, Robin Baker set up series of experiments in order to understand the human sense of direction by blindfolding the students inside the bus. When blindfolded, the bus was driven to certain places and then the students were asked about their point of departure. Interestingly, this British biologist utilize the magnetic and nonmagnetic bars within their brass.

The result was quite interesting as the students which have the magnetic bars inside their brass was able to point the direction of where their homes are. However, Baker’s result was rejected by Caltech geophysicist Joe Kirschvink as Baker’s experiments were contaminated. Meanwhile, study published in 1983 suggested that our sinus bones are actually magnetic, implying to the possibility of sensing the magnetic poles created by the Earth’s magnetic core.

Magneto-receptors in Animals
So, how actually the animals are able to sense the magnetic field in nature? The answer lies on they have been built with magneto-receptors. In birds, they are built by Cryptochrome model which is located mysteriously in double cone cells. This is actually located inside the eyes acting like wave sensor. This sensor is able detect short-wavelength light. Unlike human’s eyes which are only able to see visible lights, the birds actually could see the world in form of short-wavelength such as micro, radio or even ultra violet waves.

Some species of fish also has ability in sensing magnetic field because they have magneto-receptor cells built-in inside their nose. Salmon is one of the fish that is able to do sensing because its nose has this sensor located between ciliated olfactory sensory cells.

Based on above explanation, the internal compass which probably is inside our body is still not to be found yet. The possibility of having internal compass might have been in the discovery of magnetic bones located in our nose. However, compare to the birds’ ability in their eyes, it is impossible to human to have this ability unless we evolve.

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[1] Image is downloaded from www.wikipedia.org