One of the mysteries of palaeontology is the flipside of the mass extinctions, or an evolutionary explosion. The famous Cambrian Explosion is an interesting period. In a relatively brief period of time, the number of species on Earth multiplied to a degree they have not seen before or since.
It's not hard to understand mass extinction. It's easy to kill things. What's hard to explain is how evolution seems to work at a plodding deliberate pace, and then suddenly leaps forward.
There are many theories, some discarded, some still considered, about how this occurred.
I wonder if these bursts of evolution and diversity correspond to magnetic pole reversals? We know mutations occur more often in high radiation periods. They have found that the magnetic poles of Earth reverse from time to time. Without the proper configuration of the magnetic field, Earth would be without shielding from cosmic radiation that the field provides. Perhaps when this field was temporarily down, the increased radiation caused increased mutation?
Some believe that there was nothing special about the Cambrian Explosion, it was just a developmental threshold that was passed when conditions were ripe for life to expand into all the niches that Earth provided it.
If that is true, is it possible for this to happen again?
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