Role in ArgumentDiff: Hard
Logic Breakdown
Passage Summary: Early Earth was a chaotic mess of asteroid hits that likely killed off any early life, while Mars was much calmer. Because Mars could have developed life earlier and we know Mars rocks land on Earth, it's possible our life actually started on Mars and hitched a ride here.
Conclusion: Life on Earth might have originated from microbes traveling on meteorites from Mars.
Reasoning: Early Earth was too bombarded for life to survive, but Mars escaped this, meaning life could have existed there first; since Mars meteorites land on Earth, they could have transported those microbes.
Analysis: The statement in question acts as an intermediate conclusion. It is supported by the facts about the different bombardment levels of Earth and Mars. In turn, it serves as a necessary premise for the final conclusion that life could have migrated from Mars to Earth. Without the possibility of Mars having life before Earth, the 'hitchhiking microbe' theory wouldn't work.
Conclusion: Life on Earth might have originated from microbes traveling on meteorites from Mars.
Reasoning: Early Earth was too bombarded for life to survive, but Mars escaped this, meaning life could have existed there first; since Mars meteorites land on Earth, they could have transported those microbes.
Analysis: The statement in question acts as an intermediate conclusion. It is supported by the facts about the different bombardment levels of Earth and Mars. In turn, it serves as a necessary premise for the final conclusion that life could have migrated from Mars to Earth. Without the possibility of Mars having life before Earth, the 'hitchhiking microbe' theory wouldn't work.
Passage Stimulus
Passage Redacted
Unlock Full Passage20.Which one of the following most accurately describes the role played in the astronomer's argument by the statement that there could have been microbial life on Mars prior to there being such life on Earth?
Correct Answer
C
The claim is supported by earlier evidence and is required for the main conclusion’s possibility; without earlier life on Mars, life on Earth could not have originated from Mars. Yet even if true, it doesn’t establish that Earth’s life did come from Mars, only that it could have.
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