Theoretical Timeline from Billions of Years to Thousands of Years

4.6 Billion Years Ago

The Origin of The Earth

3.5 - 3.8 Billion Years Ago

First Life Arises, Simple Celled Bacteria (Prokaryotes)

3 Billion Years Ago

Photosynthesis Began

2 Billion Years Ago

First Complex Cells with Organelles (Eukaryotes)

1 Billion Years Ago

First Multicellular Life Begins, Cells with Multiple Organelles

600 Million Years Ago

Simple Animals Appear, Such as Jellyfish and Worms

570 Million Years Ago

Arthropods (Ancestors of Insects, Arachnids and Crustaceans)

550 Million Years Ago

Complex Animals, Such as Bilaterians

520 Million Years Ago

First Appearance of Trilobites

500 Million Years Ago

First Fish and Proto-Amphibians Begin to Appear

475 Million Years Ago

First Land Plants and Fungi Form

400 Million Years Ago

Insects and Seeds

360 Million Years Ago

Amphibians Evolve, Most of The Land Surface Was Covered in Fern Forest Which Eventually Would Become Coal

300 Million Years Ago

Reptiles Evolve

250 Million Years Ago

First Mass Extinction of Life Forms, Including Trilobites

231 Million Years Ago

Dinosaurs First Appeared

200 Million Years Ago

First Mammals Appear

150 Million Years Ago

First Birds

130 Million Years Ago

First Flowering Plants

120 Million Years Ago

First Appearance of Bees

65 Million Years Ago

Second Mass Extinction, Non-Avian Dinosaurs Die Out

45 Million Years Ago

First Modern Mammals

35 Million Years Ago

First Grasses Form

3 Million Years Ago

First Hominids (Australopithecus)

2.6 Million Years Ago

Start of the Ice Age

2.5 Million Years Ago

Appearance of Homo sapiens

200,000 Years Ago

Appearance of Modern Humans

100,000 Years Ago

Humans Colonise All Habitable Land Masses

25,000 Years Ago

Neanderthals Died Out, Leaving Space For The Homo Sapiens to Become the Only Species of Human

11,500 Years Ago

End of the Ice Age

15,000 Years Ago

Agriculture Began