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The first eon in Earth's history, the Hadean, begins with the Earth's formation and is followed by the Archean eon at 3.8 Ga. [2]: 145 The oldest rocks found on Earth date to about 4.0 Ga, and the oldest detrital zircon crystals in rocks to about 4.4 Ga, [34] [35] [36] soon after the formation of the Earth's crust and the Earth itself.
At long irregular intervals, Earth's biosphere suffers a catastrophic die-off, a mass extinction, [9] often comprising an accumulation of smaller extinction events over a relatively brief period. [10] The first known mass extinction was the Great Oxidation Event 2.4 billion years ago, which killed most of the planet's obligate anaerobes.
Iron columns had been used in Wren's designs for the House of Commons and were used in several early 18th-century churches in London, but these supported only galleries. In the second half of the 18th century the decreasing costs of iron production allowed the construction of major pieces of iron engineering.
These timelines of world history detail recorded events since the creation of writing roughly 5000 years ago to the present day. For events from c. 3200 BC – c. 500 see: Timeline of ancient history; For events from c. 500 – c. 1499, see: Timeline of post-classical history; For events from c. 1500, see: Timelines of modern history
Sometimes Doors were made from ox-hide. Doors between houses were often so low, that people needed to crouch to walk though them. Houses would usually have no windows, if they did it would be made of clay or wooden grilles. Floors would usually be made of dirt. Mesopotamian houses would often crumble. Houses needed to be repaired often. [14] [15]
The earliest Earth crust probably forms similarly out of similar material. On Earth the pluvial period starts, in which the Earth's crust cools enough to let oceans form. c. 4,404 Ma – First known mineral, found at Jack Hills in Western Australia. Detrital zircons show presence of a solid crust and liquid water.
The history of life on Earth traces the processes by which living and extinct organisms evolved, from the earliest emergence of life to the present day. Earth formed about 4.5 billion years ago (abbreviated as Ga, for gigaannum) and evidence suggests that life emerged prior to 3.7 Ga. [1] [2] [3] The similarities among all known present-day species indicate that they have diverged through the ...
The date used as the end of the ancient era is arbitrary. The transition period from Classical Antiquity to the Early Middle Ages is known as Late Antiquity.Late Antiquity is a periodization used by historians to describe the transitional centuries from Classical Antiquity to the Middle Ages, in both mainland Europe and the Mediterranean world: generally from the end of the Roman Empire's ...