According to everything we know, 4.6 billion years ago, the glowing fireball that was to become the Earth, the Sun and other planets were all formed from a cloud of gas. The universe itself was already 9.2 billion years old.
Biological evolution replaces chemical evolution 500 million years after Earth is formed. This marks the beginning of the development of life.
Precursors of cyanobacteria (formerly called blue-green algae) are the first cells whose traces can be detected in old rocks. Thanks to their cell membrane they were able to regulate the exchange of substances and energy with their environment.
Cells are developing the ability to produce energy from sunlight ever more efficiently. Over millions of years, the oxygen produced leads to the formation of water insoluble metal salts in the oceans. This results in the significant banding layers which are being mined today.
Towards the end of this age, cells appear for the first time which, unlike bacteria, have a real cell nucleus in which their genetic material is stored in a more protected way.
The first fossils of clusters of interconnected cells date from this period. By connecting, they lay the foundation for the division of labour among cells and the development of more complex living beings.
The oxygen content in the sea rises sharply, and within 5–10 million years most of the blueprints for the creatures that still exist today are created. Fish are the first creatures with an internal skeleton and flexible spine.
The first plants and insects conquer the land and many new species emerge. A tropical climate prevails, but the plants fundamentally change it: they bind carbon dioxide (a greenhouse gas) from the atmosphere, the temperature on earth drops. At the same time, the oxygen content of the atmosphere increases.
At the beginning of the Silurian, vertebrates develop movable jaws that allow them to grasp, hold and chop food. This opens up completely new feeding possibilities for the jawed animals.
Multiple rapid climate changes and lower oxygen levels in the water lead to the third major extinction. Amphibians — vertebrates that can breathe air and live on land — have opened up the land as a new habitat.