We know that birds navigate by the magnetic field, only the magnetic field changes, and the birds will be lost fall,

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Specific proteins in migratory birds eye "cryptochrome" Maybe this is the light-dependent magnetic field sensing of the media. Light stimulation of this protein produced a pair of free radicals, free radicals can be carried by the electron spin may be able to perceive the special properties of Earth's magnetic field.

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Migratory birds into the power failure and lost the ability to identify the direction, there are other serious consequences, including:
- All animals, including the human immune system will be significantly weakened.

- changes in the crust will be more frequent volcanic and more intense tectonic movements, earthquakes and landslides.

- weakening the magnetic field caused by cosmic rays have greatly increased, due to radioactive contamination will cause more cancer.

- asteroids may be more accessible to the Earth.

- changes in Earth's gravity field.

All these may be added together, not difficult to find civilization, 2012, Earth will be threatened. They also speculated that a similar event in the distant past have occurred on Mars.