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  2. Geologic time scale - Wikipedia

    en.wikipedia.org/wiki/Geologic_time_scale

    The geologic time scale is a way of representing deep time based on events that have occurred throughout Earth's history, a time span of about 4.54 ± 0.05 Ga (4.54 billion years). [5] It chronologically organises strata, and subsequently time, by observing fundamental changes in stratigraphy that correspond to major geological or ...

  3. Timeline of the evolutionary history of life - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_the...

    539 Ma – present. The Phanerozoic Eon (Greek: period of well-displayed life) marks the appearance in the fossil record of abundant, shell-forming and/or trace-making organisms. It is subdivided into three eras, the Paleozoic, Mesozoic and Cenozoic, with major mass extinctions at division points.

  4. Timeline of human evolution - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_human_evolution

    The timeline of human evolution outlines the major events in the evolutionary lineage of the modern human species, Homo sapiens, throughout the history of life, beginning some 4 billion years ago down to recent evolution within H. sapiens during and since the Last Glacial Period. It includes brief explanations of the various taxonomic ranks in ...

  5. Devonian - Wikipedia

    en.wikipedia.org/wiki/Devonian

    The Devonian (/ dəˈvoʊni.ən, dɛ -/ də-VOH-nee-ən, deh-) [9][10] is a geologic period and system of the Paleozoic era during the Phanerozoic eon, spanning 60.3 million years from the end of the preceding Silurian period at 419.2 million years ago (Ma), to the beginning of the succeeding Carboniferous period at 358.9 Ma. [11]

  6. Phanerozoic - Wikipedia

    en.wikipedia.org/wiki/Phanerozoic

    The Quaternary spans from 2.58 million years ago to present day, and is the shortest geological period in the Phanerozoic Eon. It features modern animals, and dramatic changes in the climate. It is divided into two epochs: the Pleistocene and the Holocene. The Pleistocene lasted from 2.58 million to 11,700 years ago.

  7. History of life - Wikipedia

    en.wikipedia.org/wiki/History_of_life

    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 ...

  8. Geochronology - Wikipedia

    en.wikipedia.org/wiki/Geochronology

    Geochronology. An artistic depiction of the major events in the history of Earth. Geochronology is the science of determining the age of rocks, fossils, and sediments using signatures inherent in the rocks themselves. Absolute geochronology can be accomplished through radioactive isotopes, whereas relative geochronology is provided by tools ...

  9. Miocene - Wikipedia

    en.wikipedia.org/wiki/Miocene

    The Miocene (/ ˈ m aɪ. ə s iː n,-oʊ-/ MY-ə-seen, -⁠oh-) [6] [7] is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words μείων (meíōn, "less") and καινός (kainós, "new") [8] [9] and means "less recent" because it has 18% fewer modern marine invertebrates ...