The inverse, or 'reverse' polarity is also equally as probable and stable. Paleomagnetic studies have shown that polarity reversals of Earth's magnetic field are not periodic and cannot be predicted.

Secrets of ‘polar dinosaur’ forest home revealed for first time in 120 million years - At least 100 million years ago, dinosaurs thrived on the piece of land that is modern-day Australia ...

And although less than 1.2% of these polar areas are covered in vegetation, the scientists discovered that over 90% of the rocks they looked at were colonized by the cyanobacteria. Similar activity ...