Explanation – The Great Oxygenation Event, also known as the “Oxygen Catastrophe” or “Oxidation Catastrophe,” occurred approximately 2.4 billion years ago during the Paleoproterozoic era. It marks a period when the Earth’s atmosphere experienced a significant increase in oxygen levels due to the evolution of oxygen-producing organisms like cyanobacteria. This event had a profound impact on the Earth’s atmosphere, allowing for the proliferation of oxygen-dependent life forms and paving the way for the diversification of complex life.

Source: Forum IAS