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4400 BCE
earth is formed
Earth was formed about 4.5 million years ago by collisions in the giant disc-shaped cloud of material that also formed the sun -
4 BCE
1st forms of life
For the next 1.3 billion years the archean period, first life begins to appear and the words landmass began to form. Earth's initial life forms were bacteria -
2 BCE
oxygen enters the atmosphere
Tiny organisms known as cyanobacteria conducted photosynthesis using sunshine water and carbon dioxide to produce carbohydrates but roughly 2.45 million years ago the isotonic ratio of sulfur transferred indicating that for the first time oxygen was gonna become a significant component of earth's atmosphere -
300
pangaea formed
About 300 million years ago, Earth didn't have seven continents, but instead one massive supercontinent called Pangaea, which was surrounded by a single ocean called Panthalassa -
375
pangaea begins to break up
Pangaea began to break up in the Jurassic Period about 180 million years ago and was mostly broken up by 100 million years ago. -
Mar 21, 1000
3rd major mass extinctions
The third largest extinction in Earth's history, the Ordovician-Silurian mass extinction During the Ordovician, most life was in the sea, so it was sea creatures such as trilobites, brachiopods and graptolites that were drastically reduced in number. -
Mar 21, 1000
permian mass extintion
The event turns out to have been complex, as there were at least two separate phases of extinction spread over millions of years. Marine creatures were particularly badly affected and insects suffered the only mass extinction of their history. -
Mar 21, 1500
cretacestous-tertiary mass exectintion
The Cretaceous-Tertiary mass extinction - also known as the K/T extinction - is famed for the death of the dinosaurs. However, many other organisms perished at the end of the Cretaceous including the ammonites, many flowering plants and the last of the pterosaurs. Some groups had been in decline for several million years before the final event that destroyed them all. It's suggested that the decline was due to flood basalt eruptions affecting the world's climate -
triassic-jurasstic mass extintion
During the final 18 million years of the Triassic period, there were two or three phases of extinction whose combined effects created the Triassic-Jurassic mass extinction event. Climate change, flood basalt eruptions and an asteroid impact have all been blamed for this loss of life. -
1st multicellular life
about 2.1 billion years ago. In fact, acritarchs are the most common fossils of the late Proterozoic. Some are thought to have been the resting stages, or cysts, of dinoflagellates, which are one of the most prominent groups of planktonic -
1st eukaryotes
An important evolutionary innovation was multicellularity. The oldest known possible multicellular eukaryote is Grypania spiralis, a coiled, ribbon-like fossil two millimeters wide and over ten centimeters long. It looks very much like a coiled multicellular alga and has been described from banded iron formations in Michigan 2.1 billion years old. -
1st homo sapiens
The species that you and all other living human beings on this planet belong to is Homo sapiens. During a time of dramatic climate change 200,000 years ago, Homo sapiens evolved in Africa. -
Period: to
uy
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late devoniar mass extintion
Three quarters of all species on Earth died out in the Late Devonian mass extinction, though it may have been a series of extinctions over several million years, rather than a single event over 100 million years later
