Compare the early Earth atmosphere to Modern Earth atmosphere
The early Earth atmosphere was very different from the modern Earth atmosphere in terms of composition. The early Earth atmosphere is believed to have been primarily made up of gases like hydrogen, helium, methane, and ammonia. It was also very hot and lacked oxygen.
In contrast, the modern Earth atmosphere is predominantly made up of nitrogen (78%) and oxygen (21%), with trace amounts of other gases like carbon dioxide, argon, and water vapor. It is much cooler and the presence of oxygen allows for aerobic respiration and the formation of the ozone layer.
Additionally, the early Earth atmosphere lacked the protective ozone layer that shields the planet from harmful ultraviolet radiation, which played a significant role in shaping the evolution of life on Earth. Overall, the early Earth atmosphere was very different from the modern atmosphere and has undergone significant changes over billions of years.