Question

5. Describe how the cooling of the Earth affected the development of the continents, oceans, and atmosphere. 6. In the exercise, you labeled five periods of mass extinction on your time scale. Research the following questions: what are some proposed causes of these extinctions? Is the cause of any of the mass extinctions definitely known? Consider using Google Scholar instead of Goog le when researching this question, and consult your instructor on the rules of citation

Answer 1

Answer:

5. After just the earth was formed, there was cluster of super-heated gases which escapes into the outer space but as Earth started cooling i.e. temperature starting reaching below the boiling point of water, these gases got held by earth's gravity thus forming the atmosphere. Cloud started to form as water vapor started to condense. At one point of time, there was a period of prolonged rain which continued for enough time to create oceanic bodies. Landmass was created much later.

6. Some proposed causes of mass extinctions are: extensive volcanic activity, asteroid impact, beginning of a glacial period with changes in sea level, climate change, change in ocean and atmosphere chemistry, decrease in oxygen level.

No, these are all hypothesized causes that are stated based on evidences. But, these causes are not effective for every mass extinction. Volcanic activity is one of the major causes that is common in most of the cases while the most celebrated theory of asteroid impact is taken as the cause in just one event.