454
Lesson 454 of 500 · Extra Passages
⭐ 30 XPEarth History
📖Story Brief #454
Earth has a long and fascinating history that stretches back about 4.
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Earth has a long and fascinating history that stretches back about 4.5 billion years. Scientists study this history to understand how our planet has changed over time. One way they do this is by examining rock layers, known as strata. Each layer represents a different period in Earth's history, and the fossils found in these layers give clues about what life was like at that time. For example, dinosaur fossils found in certain strata indicate that they roamed the Earth during the Mesozoic Era, which lasted from about 252 to 66 million years ago. By dating these rock layers, scientists can create a timeline of events, such as when the first plants appeared or when mass extinctions occurred. This timeline helps us understand how life has evolved and how Earth itself has transformed through processes like volcanic eruptions and plate tectonics.
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1 of 2How do scientists study Earth's history?
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