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Dates and Events
Dates & Events Test I
| Term | Definition |
|---|---|
| 13.7 billion years ago | Origin of the Universe (Big Bang Theory) |
| 4.6 billion years ago | Origin of the Earth (Solar Nebula Theory) based on the age of asteroids |
| 4.4 billion years ago | first surface water on Earth |
| 4.2 billion years ago | oldest known rocks (pieces of Zircon; inclusions inside other rocks) had to be water to move rocks |
| 4.0 billion years ago | oldest known rock group: Acasta Gneiss in Canada |
| 3.8 billion years ago | oldest known documented life: Archeabacter |
| 2.1 billion years ago | Last significant Banded Iron Formations (BIFs) significance: no free oxygen in the Earth's atmosphere |
| 1.9 billion years ago | First evidence of a multi-celled organism on Earth: red algae |
| 1.8 billion years ago | First formation of coninental red beds on Earth. Significance: free oxygen in the atmosphere |
| 1.1 billion years ago | First supercontinent forms on Earth: Rodinia |
| 750 million years ago | Snowball Earth Theory: Earth is encased in a ball of ice. Spike in ancient marine phosphorus concentration (from 750-635 MYA) linked to emergence of complex life. |
| 650 million years ago | Second supercontinent forms: Pannotia |
| 620 million years ago | Significant emergence of marine multi-celled organisms appear on Earth: Ediacaran Fauna |
| 560 million years ago | Oldest skeletonized organizm: Coronacollin acula |
| 545 million years ago | Most major phylum (body plans) are present on Earth |
| 444 million years ago | First major mass extinction even on the face of the Earth. End of Ordovician Event |
| 359 million years ago | Second major mass extinction even on the face of the Earth. End Devonian Event |
| 251 million years ago | 3rd major mass extinction event on the face of the Earth (greatest known mass extinction event in the history of the Earth) End Permien Event. Third supercontinent forms: Pangea |
| 200 million years ago | Fourth major mass extinction event on the face of the Earth: End Triassic Event. |
| 65.5 million years ago | End of Cretaceous Event. Complete demise of the dinosaur. |