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When did life originate on Earth?

Answer 1

Hailey Alexander

See explanation.

a few conclusions drawn from science

When oxygen first appeared, it was 3.2 billion years ago (bya)

Two bya in unicellular life

Evolution from unicellular to multicellular: less than two bya

650 million years ago (mya): sea life

Worms with legs: 570 mya

Tree Wattizea: 380 Mya

Movement of animals from land to sea: 400–365 mya

Insects: 359–299 years ago

Dinosaurs with small wings: 160 mya

Bates: 50 million years

47 mya Anthropoid (human-like) primate Ida (female)

Unquestionably, you and I: Right now

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Answer 2

Hailey Alexander

It is estimated that between 3.5 and 4 billion years ago, life first emerged on Earth.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.