It has long been known as ESP, Spider Sense, or the ability to see things before they happen. But now scientists have proved that humans really do have a sixth sense - that lets them detect magnetic fields.

一直以来，第六感也被称为超感知觉、蜘蛛感应，也就是预知未来事物的能力。但现在科学家已证实人类确实有第六感，正是这第六感让人类能够感应到磁场。

Tests have shown that mankind may have the same innate¹ sense of Earth’s magnetic field that has long been proved to exist in animals.

By putting a protein from the human retina（视网膜） into fruit flies, researchers noticed that the insect modified its flight path just as if its eye had not been altered.

This suggests that the 'sixth sense' does exist in humans but we might not be aware of it.

Animals use such sight to navigate² long distances during migration³ or, in the case of birds, to ‘see’ where they are going.

The complex tests involved examining the process by which light goes through a bird’s eye, which has intrigued⁴（使迷惑） the scientific community for more than 30 years.

In the late 1970s, the physicist⁵ Klaus Schulten concluded that birds navigate by relying on geomagnetically sensitive biochemical reactions in their eyes.

Tests have shown that the special cells in the eye carry out this function using the protein cryptochrome（隐花色素） .

Professor Reppert’s team used wild fruit flies and replaced their version of cryptochrome with the human equivalent then put them in a maze⁶（迷宫，迷惑） with each wing wrapped in a metal coil.

They then sent a current through it so that the coil was magnetised in a way which mimicked⁷ Earth’s electromagnetic field.

The flies responded in exactly the same way as if they had their own cryptochrome, by either avoiding the magnetic fields or moving towards them if the researchers had placed sugar nearby.

The new study was published in the journal Nature Communications.