This section provides information about the evolution of life on Earth. For reasons of simplicity some important events and life forms were selected for each geological time span. However this should not give the impression that the evolution of life on Earth is or was a sequential event. Many life forms that were not mentioned in this text were very successful and have evolved or in some cases maintained a very successful life strategy. Prokaryotes, for example are the most successful and abundant organisms on Earth, in both numbers and biomass and still make up to 90% of the total weight of living things. For further information on each geological period or special life forms mentioned, there are links to other websites about this time.

The evolution of life is organized into 20 sections referring to their biological and geological significance.

• Birth of Earth – approximately 4600 million years ago – The Hadean Period (4600 m.y. – 3800 m.y.)
• The earliest cells and stromatolites – The Archaean Period (3800 m.y. – 2500m.y.)
• The first algae – 1200 million years ago – The Proterozoic Era (2500 m.y. – 544 m.y.)
• The Vendian animals – 570 million years ago – The Vendian Period (650 m.y. – 544 m.y)
• The Cambrian Explosion – The Cambrian Period (544m.y.- 505 m.y.)
• The Rise of the fish – The Ordovician Period (505 m.y.-440 m.y.)
• Venturing on land – the Silurian Period (440 m.y. – 410 m.y.)
• •Invasion of the land – the Devonian period (410m.y. – 360m.y.)
• Reptiles and Conifers – the Carboniferous Period (360m.y. – 286m.y.
•   Pangea – the Permian period (286m.y.- 248m.y.)
• Mammals and dinosaurs – the Triassic period (248m.y.-213m.y.)
• Dinosaurs and birds – the Jurassic period (213 m.y. – 145 m.y.)
• The final season of the dinosaurs – The Cretaceous period (145m.y.-65m.y.)
• Archaic mammals and early primates – the Paleocene epoch (65m.y.- 55.5m.y.)
• Whales and horses – The Eocene epoch (55.5 m.y. – 33.7m.y.)
• Grasses and primates – the Oligocene epoch (33.7m.y. – 23.8m.y.)
• Kelp forests and horses – the Miocene epoch (23.8 m.y. – 5.3m.y.)
• The first hominids – the Pliocene epoch (5.3 m.y. – 1.8 m.y.)
• Glaciation, the Moa and Homo sapiens – the Pleistocene epoch (1.8 m.y. – 10,000 y.)
• The Age of Humans – the Holocene epoch (8,000 years – present)

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