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Late Devonian: 375 million years ago, 75% of species lost, including most trilobites. End Permian, The Great Dying: 251 million years ago, 96% of species lost, including tabulate corals, and most trees and synapsids. End Triassic: 200 million years ago, 80% of species lost, including all conodonts. End Cretaceous: 66 million years ago, 76% of ...
t. e. This timeline of prehistory covers the time from the appearance of Homo sapiens approximately 315,000 years ago in Africa to the invention of writing, over 5,000 years ago, with the earliest records going back to 3,200 BC. Prehistory covers the time from the Paleolithic (Old Stone Age) to the beginning of ancient history .
Earth formed in this manner about 4.54 billion years ago (with an uncertainty of 1%) [25] [26] [4] and was largely completed within 10–20 million years. [27] In June 2023, scientists reported evidence that the planet Earth may have formed in just three million years, much faster than the 10−100 million years thought earlier.
The meteorite samples, however, show a spread from 4.53 to 4.58 billion years ago. This is interpreted as the duration of formation of the solar nebula and its collapse into the solar disk to form the Sun and the planets. This 50 million year time span allows for accretion of the planets from the original solar dust and meteorites.
The Great Oxidation Event ( GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, Oxygen Crisis or Oxygen Holocaust, [ 2] was a time interval during the Earth 's Paleoproterozoic era when the Earth's atmosphere and shallow seas first experienced a rise in the concentration of free oxygen. [ 3]
The Upper Paleolithic (or Upper Palaeolithic) is the third and last subdivision of the Paleolithic or Old Stone Age. Very broadly, it dates to between 50,000 and 12,000 years ago (the beginning of the Holocene ), according to some theories coinciding with the appearance of behavioral modernity in early modern humans, [ 1] until the advent of ...
In physical cosmology, the age of the universe is the time elapsed since the Big Bang.Astronomers have derived two different measurements of the age of the universe: [1] a measurement based on direct observations of an early state of the universe, which indicate an age of 13.787 ± 0.020 billion years as interpreted with the Lambda-CDM concordance model as of 2021; [2] and a measurement based ...
The 10th millennium BC spanned the years 10,000 BC to 9001 BC (c. 12 ka to c. 11 ka). It marks the beginning of the transition from the Palaeolithic to the Neolithic via the interim Mesolithic (Northern Europe and Western Europe) and Epipaleolithic (Levant and Near East) periods, which together form the first part of the Holocene epoch that is generally believed to have begun c. 9700 BC (c. 11 ...