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5 Cards in this Set
- Front
- Back
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When did some scientists propose that life originated in Earth’s oceans?
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Between 3.9 and 3.4 billion years ago
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What is a fossil?
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It is evidence of an organism that lived
long ago |
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What are paleontologists?
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Scientists who
study ancient life |
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What are fossils used for?
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They use fossils
to determine the kinds of organisms that lived during the past and sometimes to learn about their behavior. |
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What is a trace fossil?
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An indirect evidence
left by an animal and may include a footprint, a trail, or a burrow. |
