Formation of the Earth's Atmosphere. The early Earth was very different from our Earth today. The early Earth experienced frequent impacts from asteroids and meteorites and had much more frequent volcanic eruptions. There was no life on Earth for the first billion years because the atmosphere was not suitable for life.
Answer: B:The drought decreased the grass and vegetation on the ground, leaving only vegetation on shrubs and trees above the ground. Natural selection selected for the tortoises with the domed shells and hoods.
Explanation: