Our planet’s magnetic field helps protect life from energetic particles that would otherwise hit it from outer space. Mars currently doesn’t have a strong magnetic field, and it is believed that the conditions on the red planet are so damaging to life that the microbes that could potentially live on the planet would be found way beneath the surface.
On Earth, the magnetic field is a crucial component for life to flourish on the surface.
However, our planet’s magnetic field changes, with poles sometimes alternating and the field weakening or mostly vanishing at times. Still, an analysis of those events showed nothing out of the ordinary – no considerable connections to extinctions, no significant ecological upsets.
A recently published paper in Science features a surprisingly accurate dating for a past magnetic field flip by analyzing rings of trees that have been dead for tens of thousands of years. That shows that the flip is associated with climate change. However, the paper continues by attempting to tie the flip to everything from a minor extinction.
The data suggests that the magnetic field began to decrease 42,350 years ago, and it reached the lowest level some 41,800 years ago, which approximately 300 years before the pole flip.
The curious thing is, many regions, including Australia, faced a significant extinction of megafauna that peaked approximately 42,000 years ago, which is suggestive of a link to the modified rainfall provoked by the change in poles. However, that idea is still under intense debate as extinction events usually extend for a long time before and after peaking.