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What is the Hadean Eon?

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The Hadean Eon is the earliest eon in Earth's history, starting from the formation of the Earth about 4.6 billion years ago to about 4 billion years ago. It is characterized by the formation of the Earth's crust and the presence of molten rock.

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What is the Archean Eon?

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The Archean Eon is the second eon in Earth's history, lasting from about 4 billion to 2.5 billion years ago. It is known for the formation of the first stable continental crust and the emergence of simple life forms.

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What is the Proterozoic Eon?

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The Proterozoic Eon spans from about 2.5 billion to 541 million years ago. It is marked by the buildup of atmospheric oxygen and the appearance of multicellular life.

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What is the Phanerozoic Eon?

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The Phanerozoic Eon is the current eon, beginning around 541 million years ago. It is characterized by the abundance of fossil evidence and the development of complex life forms, including plants and animals.

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NGSS.MS-LS4-1

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When did the earliest life on Earth begin?

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The earliest life on Earth began approximately 3,500 million years ago during the Archean Eon.

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In which eon did humans evolve?

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Humans evolved during the Phanerozoic Eon.

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NGSS.MS-LS4-2

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What is the Quaternary Period?

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The Quaternary Period is the most recent geological time period, starting about 2.6 million years ago and continuing to the present. It is characterized by the development of humans and significant climate changes.

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NGSS.MS-ESS2-2

NGSS.MS-LS4-2

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What is the Precambrian Era?

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The Precambrian Era encompasses the Hadean, Archean, and Proterozoic eons, covering about 90% of Earth's history and including the formation of the Earth and the earliest life forms.

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NGSS.HS-ESS1-6

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What significant event occurred during the Cambrian Period?

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The Cambrian Period, starting around 541 million years ago, is known for the 'Cambrian Explosion,' a rapid diversification of life forms in the oceans.

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NGSS.MS-LS4-1

NGSS.MS-LS4-2

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What are fossils?

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Fossils are the preserved remains or traces of ancient organisms, providing evidence of past life and helping scientists understand Earth's history.

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