For what part of the day did only unicellular life-forms exist?

At what time of day did the first plants appear on earth?

At what time of day did mammals appear on earth?

Question:

For what part of the day did only unicellular life-forms exist?

Answer:

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.

Question:

At what time of day did the first plants appear on earth?

Answer:

The first land plants appeared around 470 million years ago, during the Ordovician period, when life was diversifying rapidly. They were non-vascular plants, like mosses and liverworts, that didn't have deep roots.

Question:

At what time of day did mammals appear on earth?

Answer:

The period between the extinction of the dinosaurs and the present day is called the Age of Mammals or Cenozoic. Mammals appeared on the earth long before the extinction of the dinosaurs; in fact, dinosaurs and mammals originated within 10 million years of each other, in the late Triassic about 200 million years ago.

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