What happens if we don't get enough oxygen? We'll die! But what if the air has more oxygen? We'll die!
Earth's atmosphere had no oxygen about 2 billion years ago. But a new bacterium emerged. Bacteria. These microorganisms squander oxygen.
Today, the Oxygen level is 21% but during that period, oxygen levels rise at a very fast rate, approximately 77-79%.
Anaerobic bacteria means bacteria that don't need oxygen; oxygen is like poison to them. The levels of this type of bacteria dropped quickly!
Methane present in the atmosphere keeps the Earth warm, but when excess oxygen is combined with methane, Carbon-dioxide was created.
Soon, CO2 levels rise suddenly, thus cooling down the earth! The temperature dropped so quickly that all the water bodies turned into ice.
Earth was like a giant ice ball! Earth's minerals and nutrition levels fluctuated.
Climate, nutrition, and temperature changes produced the mass extinction that wiped off 99 percent of Earth's life. But, how did dinosaurs, reptiles, and birds evolve?
As oxygen levels rose, new species were able to emerge. Despite the massive annihilation, some life survived and developed!