History of life

Archean era

38,000 BCE

It was during the Archean era that life first arose on Earth. At this time there were no continents, just small islands in a shallow ocean.

Cryogenian period

850 BCE

A succession of incredibly harsh ice ages waxed and waned during the Cryogenian. It is nicknamed Snowball Earth as it's been suggested that the glaciation was so severe it may even have reached the equator.

Ordovician period

495 BCE

During the Ordovician, a few animals and plants began to explore the margins of the land, but nothing colonised beyond these beachheads, so the majority of life was still confined to the seas.

Silurian period

433 BCE

The Silurian period was the time when reefs got their act together, grew really big and created a completely new type of ecosystem for marine life. Silurian reefs weren't built by the same types of coral around now, but by a host of tabulate and rugose corals, crinoids and sponges.

Devonian period

417 BCE

The Devonian is also known as the Age of Fishes, since several major fish lineages evolved at this time. Sea levels were high and the global climate was warm.

Permian period

290 BCE

The Permian started with an ice age and ended with the most devastating mass extinction the Earth has ever experienced. In fact, at least two mass extinctions occurred during this time.

Jurassic period

205 BCE

The Jurassic began after the mass extinction event that ended the Triassic. Life, however, was quick to recover from this blow and the Jurassic eventually became host to the most diverse range of organisms that Earth had yet seen.

Cretaceous period

142 BCE

The Cretaceous ended with the most famous mass extinction in history - the one that killed the dinosaurs. Prior to that, it was a warm period with no ice caps at the poles.

Palaeocene epoch

65 BCE

The Paleocene epoch was a time of dense forests and evolutionary experiments. The extinction of the dinosaurs and other giant reptiles at the end of the Cretaceous paved the way for mammals and birds to evolve to fill those empty niches, so many new creatures appeared.

Triassic period

248

The Triassic began after the worst mass extinction ever, at the end of the Permian. Life on Earth took a while to recover and diversify. The Triassic was characterised by heat, vast deserts and warm seas.

Carboniferous period

354

The Carboniferous is famed for having the highest atmospheric oxygen levels the Earth has ever experienced and for the evolution of the first reptiles. Plants grew and died at such a great rate that they eventually became coal.

Cambrian period

545

The Cambrian is famed for its explosion of abundant and diverse life forms. Life had diversified into many forms and many ways of living: animals now swam, crawled, burrowed, hunted, defended themselves and hid away.

Ediacaran period

Feb 13, 635

Known also as the Vendian, the Ediacaran was the final stage of Pre-Cambrian time. All life in the Ediacaran was soft-bodied - there were no bones, shells, teeth or other hard parts