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Only until the Earth's surface started to cool and water vapour started to condense to produce rain, which was then stored in the oceans, did the approximately 4.54 billion year-old planet start to support life. The Archean age, which brought about the first forms of life that persisted for nearly billions of years before new species began to emerge, began with these modifications.

Over 500 million years ago, during the Ordovician period, land plants first started to emerge. Plants evolved gradually as a result of the development of vascular tissue, seed generation, and flowering, among other reproductive systems. Paleobotanists examine the fossil record in the context of the surrounding geological deposits to reconstruct the development of plant form.

• The Cambrian epoch, which began 1.9 million years ago, is the first period of the Paleozoic era. The rapid variety of life forms throughout this time was a defining feature. Metazoan and protist animals were first created.
• About 1.5 million years ago, the Silurian period began. It lasted until the end of the Ordovician period and the beginning of many Devonian periods. Beginning in the Silurian period, plants began to proliferate. However, it is not the first time that plants have existed.
• The beginning of the Devonian era came immediately after the Silurian era. It is frequently referred to as the age of fish since a great diversity of fishes developed during this time.