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oksano4ka [1.4K]
3 years ago
11

During which era was the earth dominated by mostly single-celled organisms?

Biology
2 answers:
lubasha [3.4K]3 years ago
6 0

The first known single-celled organisms appeared on Earth about 3.5 billion years ago, roughly a billion years after Earth formed. More complex forms of life took longer to evolve, with the first multicellular animals not appearing until about 600 million years ago.

charle [14.2K]3 years ago
4 0

I think it’s Proterozoic era where life on Earth was mostly single-celled and small.

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