The History Of The Earth From Formation To Present Day
Earth formed approximately 4.54 billion years ago and was mostly completed within 10–20 million years.
In 4.4 billion years ago, our planet's first oceans formed. Water vapor was freed into the Earth's atmosphere by volcanism. It then cooled, dropped back down as precipitation, and created the planet's first oceans. Some water has additionally been delivered to Earth by asteroids and comets.
3.85 billion years ago, the first life emerged on the planet.
Between 2.1 billion and 2.03 billion years ago, the increase of oxygen began rapidly, and the present situation was reached 1.5 billion years ago. Cyanobacteria make oxygen a product of photosynthesis.
700 million years ago, the first simple single-celled animals evolved.
530 million years ago, the first vertebrates in the ocean (fish) appeared on the planet.
400 million years ago, the first land plants developed. Oxygen in the atmosphere acted to form ozone, which created a layer. The ozone layer functioned as a protecting barrier to the dangerous rays coming from space, supporting plants to colonize the land.
350 million years ago, the first land vertebrates emerged. With plants being on the land to give a food source, animals quickly followed. The first to attempt onto the land was first amphibians, and reptiles emerged shortly after.
225 million years ago, the first dinosaurs developed from reptiles.
65 million years ago, the dinosaurs and many other species were gone by the after-effects of a meteorite collision. The impact set off a series of earthquakes, volcanic explosions, and tsunamis, which threw lots of dust particles and acid into the atmosphere, causing an impact winter. The dust impeded out the sunshine so plants could no longer photosynthesize, and food chains were destroyed. After the extinction of the dinosaurs, mammals developed quickly and filled the evolutionary niches they left behind.
130 thousand ago, modern humans developed. Homo sapiens emerged in the African continent from the first humans. They left Africa about 35 thousand years ago and spread worldwide.
A visualization below shows the significant events on planet Earth during its four-billion-year history.
Here is another map that shows how the coasts of the continents have changed over millions of years.