About 2.4 billion years ago, Earth's atmosphere had almost no oxygen. The microbes living at the time were anaerobic—they thrived without it and found it toxic. Then came the Cyanobacteria. These tiny organisms evolved a new trick called photosynthesis. They used sunlight to create energy and released oxygen as a waste product. For millions of years, they pumped this "waste" into the oceans and air. This triggered the Great Oxidation Event. For the existing life on Earth, it was an apocalypse. T

Known as the Great Oxidation Event, this was not a sudden catastrophe but a planetary transformation lasting hundreds of millions of years. The oxygen produced by these ancient microbes reacted with iron dissolved in the oceans, creating the banded iron formations we see in rocks today. This process likely triggered a 'Snowball Earth' – a global glaciation – as oxygen removed methane, a potent greenhouse gas, from the atmosphere. While it caused a die-off of anaerobic life that couldn't adapt, i

When Oxygen Nearly Killed All Life - Over 2.4 billion years ago, a single event changed our planet forever. How did oxygen turn Earth into a frozen world? And why did it nearly wipe out all life? This video unravels the mystery behind the Great Oxidation Event, using insights from geochemists and evolutionary biologists. A deadly transformation that shaped the world we know today. | The Brain Maze