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Late Ordovician mass extinction: 445-444 Ma Global cooling and sea level drop, and/or global warming related to volcanism and anoxia [43] Cambrian: Cambrian–Ordovician extinction event: 488 Ma: Kalkarindji Large Igneous Province? [44] Dresbachian extinction event: 502 Ma: End-Botomian extinction event: 517 Ma: Precambrian: End-Ediacaran ...
An extinction event (also known as a mass extinction or biotic crisis) is a widespread and rapid decrease in the biodiversity on Earth. Such an event is identified by a sharp fall in the diversity and abundance of multicellular organisms .
The following list is incomplete by necessity, since the majority of extinctions are thought to be undocumented, and for many others there isn't a definitive, widely accepted last, or most recent record. According to the species-area theory, the present rate of extinction may be up to 140,000 species per year. [1]
The Late Ordovician mass extinction (LOME), sometimes known as the end-Ordovician mass extinction or the Ordovician-Silurian extinction, is the first of the "big five" major mass extinction events in Earth's history, occurring roughly 445 million years ago (Ma). [1]
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 ...
The Late Ordovician is the third and final epoch of the Ordovician period, lasting 15.1 million years and spanning from around 458.2 to 443.1 million years ago. [4] [5] The rocks associated with this epoch are referred to as the Upper Ordovician Series.
For the record: 2:18 p.m. May 31, 2023: An earlier version of this story misidentified the plant that was neither growing nor deteriorating.It was Sequoia sempervirens, or coast redwood, not ...
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