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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] It is often considered to be the second-largest known extinction event just ...
The Cambrian–Ordovician extinction event, also known as the Cambrian-Ordovician boundary event, [1] was an extinction event that occurred approximately 485 million years ago (mya) in the Paleozoic era of the early Phanerozoic eon. [2] It was preceded by the less-documented (but probably more extensive) End-Botomian mass extinction around 517 ...
The Late Ordovician glaciation is widely considered to be the leading cause of the Late Ordovician mass extinction, [2] [12] and it is the only glacial episode that appears to have coincided with a major mass extinction of nearly 61% of marine life. [13]
The Ordovician (/ ɔːrdəˈvɪʃi.ən, - doʊ -, - ˈvɪʃən / or-də-VISH-ee-ən, -doh-, -VISH-ən) [ 9 ] is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period 485.4 Ma (million years ago) to the start of the Silurian Period 443.8 Ma.
The Great Ordovician Biodiversification Event (GOBE), was an evolutionary radiation of animal life throughout [ 1 ] the Ordovician period, 40 million years after the Cambrian explosion, [ 2 ] whereby the distinctive Cambrian fauna fizzled out to be replaced with a Paleozoic fauna rich in suspension feeder and pelagic animals.
The largest extinction was the Kellwasser Event (Frasnian - Famennian, or F-F, 372 Ma), an extinction event at the end of the Frasnian, about midway through the Late Devonian. This extinction annihilated coral reefs and numerous tropical benthic (seabed-living) animals such as jawless fish, brachiopods, and trilobites.
Glikson claims the impact that caused the crater may have occurred during the Late Ordovician mass extinction event. “Specifically, I think it may have triggered what’s called the Hirnantian ...
The Ordovician mass extinction did not leave the trilobites unscathed; some distinctive and previously successful forms such as the Telephinidae and Agnostida became extinct. The Ordovician marks the last great diversification period amongst the trilobites: very few entirely new patterns of organisation arose post-Ordovician.