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  2. Geologic time scale - Wikipedia

    en.wikipedia.org/wiki/Geologic_time_scale

    For example, the Cretaceous–Paleogene extinction event, marks the lower boundary of the Paleogene System/Period and thus the boundary between the Cretaceous and Paleogene systems/periods. For divisions prior to the Cryogenian , arbitrary numeric boundary definitions ( Global Standard Stratigraphic Ages , GSSAs) are used to divide geologic time.

  3. Timeline of natural history - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_natural_history

    c. 143.1 Ma – End of Jurassic and beginning of Cretaceous Period. c. 145 Ma – First mantises. c. 140 Ma – Earliest orb-weaver spiders evolve. c. 130 Ma – Laurasia and Gondwana begin to split apart as the Atlantic Ocean forms. First flowering plants. Earliest anglerfish.

  4. Cretaceous–Paleogene extinction event - Wikipedia

    en.wikipedia.org/wiki/CretaceousPaleogene...

    The Cretaceous–Paleogene (K–Pg) extinction event, [a] also known as the K–T extinction, [b] was the mass extinction of three-quarters of the plant and animal species on Earth [2] [3] approximately 66 million years ago. The event caused the extinction of all non-avian dinosaurs.

  5. Template:Paleogene graphical timeline - Wikipedia

    en.wikipedia.org/wiki/Template:Paleogene...

    Printable version; In other projects ... Cretaceous. P a l e o g e n e. Neogene. P a l e o c e n e. E o c e n e. O l i g o c e n e. ... Subdivision of the Paleogene ...

  6. Template:Cretaceous graphical timeline - Wikipedia

    en.wikipedia.org/wiki/Template:Cretaceous...

    Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Pages for logged out editors learn more

  7. Geological history of Earth - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_Earth

    The Cretaceous is justly famous for its chalk; indeed, more chalk formed in the Cretaceous than in any other period in the Phanerozoic. [51] Mid-ocean ridge activity—or rather, the circulation of seawater through the enlarged ridges—enriched the oceans in calcium; this made the oceans more saturated, as well as increased the bioavailability ...

  8. Timeline of Cretaceous–Paleogene extinction event research

    en.wikipedia.org/wiki/Timeline_of_Cretaceous...

    A study aiming to quantify the habitat of latest Cretaceous North American dinosaurs, based on data from fossil occurrences and climatic and environmental modelling, and evaluating its implications for inferring whether dinosaur diversity was in decline prior to the Cretaceous–Paleogene extinction event, was published by Chiarenza et al ...

  9. Paleogene - Wikipedia

    en.wikipedia.org/wiki/Paleogene

    The Paleogene Period (IPA: / ˈ p eɪ l i. ə dʒ iː n,-l i. oʊ-, ˈ p æ l i-/ PAY-lee-ə-jeen, -⁠lee-oh-, PAL-ee-; also spelled Palaeogene or Palæogene) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period 66 Ma (million years ago) to the beginning of the Neogene Period 23.04 Ma.