This paper proposes that the rapid extinction of Pleistocene Megafauna and the subsequent reduction in human lifespan were not caused solely by climate change or overhunting, but by a catastrophic failure of the Earth’s geomagnetic shield. We argue that a massive Plasma Bolide event ~12,900 years ago impacted the South Atlantic, creating a persistent "Reverse Flux" eddy (the South Atlantic Anomaly) that permanently destabilized the Geodynamo. This event ended a "Hyper-Shielded" epoch, plunging the biosphere into a high-radiation environment that continues to degrade biological viability and DNA integrity today.
Joshua Roland (Wed,) studied this question.