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  2. Ammonoidea - Wikipedia

    en.wikipedia.org/wiki/Ammonoidea

    They are often called ammonites, which is most frequently used for members of the order Ammonitida, the only remaining group of ammonoids from the Jurassic up until their extinction. [ 2 ] Ammonoids exhibited considerable diversity over their evolutionary history, with over 10,000 species having been described. [ 3 ]

  3. Cretaceous–Paleogene extinction event - Wikipedia

    en.wikipedia.org/wiki/Cretaceous–Paleogene...

    Ammonite genera became extinct at or near the K–Pg boundary; there was a smaller and slower extinction of ammonite genera prior to the boundary associated with a late Cretaceous marine regression, and a small, gradual reduction in ammonite diversity occurred throughout the very late Cretaceous. [73]

  4. Paleocene ammonites - Wikipedia

    en.wikipedia.org/wiki/Paleocene_ammonites

    A fossil of Hoploscaphites, an ammonite believed to have survived the K-Pg extinction event well into the Paleocene. The term Paleocene ammonites describes families or genera of Ammonoidea that may have survived the Cretaceous–Paleogene extinction event, which occurred 66.043 million years ago.

  5. Timeline of the evolutionary history of life - Wikipedia

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

    End Cretaceous: 66 million years ago, 76% of species lost, including all ammonites, mosasaurs, plesiosaurs, pterosaurs, and nonavian dinosaurs; Smaller extinction events have occurred in the periods between, with some dividing geologic time periods and epochs. The Holocene extinction event is currently under way. [12]

  6. List of ammonite genera - Wikipedia

    en.wikipedia.org/wiki/List_of_ammonite_genera

    This list of ammonites is a comprehensive listing of genera that are included in the subclass †Ammonoidea, excluding purely vernacular terms. The list includes genera that are commonly accepted as valid, as well as those that may be invalid or doubtful ( nomina dubia ), or were not formally published ( nomina nuda ), as well as junior ...

  7. List of extinction events - Wikipedia

    en.wikipedia.org/wiki/List_of_extinction_events

    Permian–Triassic extinction event 252 Ma Large igneous province (LIP) eruptions [ 23 ] from the Siberian Traps , [ 24 ] an impact event (the Wilkes Land Crater ), [ 25 ] an Anoxic event , [ 26 ] an Ice age , [ 27 ] or other possible causes

  8. Timeline of Cretaceous–Paleogene extinction event research

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

    Harold Urey argued that comet impacts may have caused mass extinctions in the past and may have been responsible for demarcating the periods of the geologic time scale. [27] 1974. Jan Smit began studying the extinction of foraminifera at the K–T boundary in Caravaca, Spain. He observed that some of these extinctions must have been rapid. [28 ...

  9. Acanthoceras (ammonite) - Wikipedia

    en.wikipedia.org/wiki/Acanthoceras_(ammonite)

    Acanthoceras is an extinct cephalopod genus belonging to the subclass Ammonoidea and family Acanthoceratidae that lived from the Albian to early Coniacian stages of the Cretaceous. [ 1 ] Description