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  2. List of extinction events - Wikipedia

    en.wikipedia.org/wiki/List_of_extinction_events

    Dresbachian extinction event: 502 Ma: End-Botomian extinction event: 517 Ma: Precambrian: End-Ediacaran extinction: 542 Ma: Anoxic event [45] Great Oxygenation Event: 2400 Ma: Rising oxygen levels in the atmosphere due to the development of photosynthesis as well as possible Snowball Earth event. (see: Huronian glaciation.)

  3. Extinction event - Wikipedia

    en.wikipedia.org/wiki/Extinction_event

    Asteroid impacts: one large impact is associated with a mass extinction, that is, the Cretaceous–Paleogene extinction event; there have been many smaller impacts but they are not associated with significant extinctions, [105] or cannot be dated precisely enough.

  4. Galactic year - Wikipedia

    en.wikipedia.org/wiki/Galactic_year

    Permian–Triassic extinction event: 0.2933 gal Cretaceous–Paleogene extinction event: 0.0013 gal Emergence of anatomically modern humans: Future (years from now) 0.15 gal Mean time between impacts of asteroidal bodies in the order of magnitude of the K/Pg impactor has elapsed. [8] 1 gal All the continents on Earth may fuse into a supercontinent.

  5. What is a mass extinction, and why do scientists think we’re ...

    www.aol.com/brief-history-end-world-every...

    The most famous of these mass extinction events — when an asteroid slammed into Earth 66 million years ago, dooming the dinosaurs and many other species — is also the most recent. But ...

  6. Background extinction rate - Wikipedia

    en.wikipedia.org/wiki/Background_extinction_rate

    Normal extinction rates are often used as a comparison to present day extinction rates, to illustrate the higher frequency of extinction today than in all periods of non-extinction events before it. [1] Background extinction rates have not remained constant, although changes are measured over geological time, covering millions of years. [2] [3] [4]

  7. Timeline of the evolutionary history of life - Wikipedia

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

    The first known mass extinction was the Great Oxidation Event 2.4 billion years ago, which killed most of the planet's obligate anaerobes. Researchers have identified five other major extinction events in Earth's history, with estimated losses below: [11] End Ordovician: 440 million years ago, 86% of all species lost, including graptolites

  8. The Most Devastating Animal Extinctions in Recent History - AOL

    www.aol.com/most-devastating-animal-extinctions...

    Here are 10 of the most devastating animal extinctions in recent history, ... The Golden Toad was last seen in 1989 and is now considered extinct. Climate change, habitat loss, and pollution ...

  9. Future of Earth - Wikipedia

    en.wikipedia.org/wiki/Future_of_Earth

    Impacts from these comets could trigger a mass extinction of life on Earth. These disruptive encounters are estimated to occur an average of once every 45 million years. [28] There is a 1% chance every billion years that a star will pass within 100 AU of the Sun, potentially disrupting the Solar System. [29]