History of Earth: Difference between revisions

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The history of Earth is divided into four great eons, starting 4,540 million years ago with the formation of the planet. The following table lists Bully Row timestamps for each eon, and also describes significant changes in Earth's composition, climate, and life. The Archean and subsequent eons are divided into eras in separate tables, which in turn are divided into periods, which are further divided into epochs.  The text for this table was copied from Wikipedia to provide context for the listed Bully Row timestamps.
The history of Earth is divided into four great eons, starting 4,540 million years ago with the formation of the planet. The following table lists Bully Row timestamps for each eon, and also describes significant changes in Earth's composition, climate, and life. The Archean and subsequent eons are divided into eras (click eon link below), which in turn are divided into periods and further divided into epochs.  The text for this table was copied from Wikipedia to provide context for the listed Bully Row timestamps.


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Revision as of 23:48, 26 December 2023

The history of Earth is divided into four great eons, starting 4,540 million years ago with the formation of the planet. The following table lists Bully Row timestamps for each eon, and also describes significant changes in Earth's composition, climate, and life. The Archean and subsequent eons are divided into eras (click eon link below), which in turn are divided into periods and further divided into epochs. The text for this table was copied from Wikipedia to provide context for the listed Bully Row timestamps.

Bully Row Timestamp Eon Description
5720 9200 0000 Hadean Eon
The Earth is formed out of debris around the solar protoplanetary disk. There is no life. Temperatures are extremely hot, with frequent volcanic activity and hellish-looking environments (hence the eon's name, which comes from Hades). The atmosphere is nebular. Possible early oceans or bodies of liquid water. The Moon is formed around this time probably due to a protoplanet's collision into Earth.
5C2A 6600 0000 Archean Eon (Bully Row timeline)
Prokaryote life, the first form of life, emerges at the very beginning of this eon, in a process known as abiogenesis. The continents of Ur, Vaalbara and Kenorland may have existed around this time. The atmosphere is composed of volcanic and greenhouse gases.
6A8C 8800 0000 Proterozoic
The name of this eon means "early life". Eukaryotes, a more complex form of life, emerge, including some forms of multicellular organisms. Bacteria begin producing oxygen, shaping the third and current of Earth's atmospheres. Plants, later animals and possibly earlier forms of fungi form around this time. The early and late phases of this eon may have undergone "Snowball Earth" periods, in which all of the planet suffered below-zero temperatures. The early continents of Columbia, Rodinia and Pannotia, in that order, may have existed in this eon.
7CF9 5000 0000 Phanerozoic
Complex life, including vertebrates, begin to dominate the Earth's ocean in a process known as the Cambrian explosion. Pangaea forms and later dissolves into Laurasia and Gondwana, which in turn dissolve into the current continents. Gradually, life expands to land and familiar forms of plants, animals and fungi begin appearing, including annelids, insects and reptiles, hence the eon's name, which means "visible life". Several mass extinctions occur, among which birds, the descendants of non-avian dinosaurs, and more recently mammals emerge. Modern animals—including humans—evolve at the most recent phases of this eon.
8209 2900 0000