Late Devonian Extinction

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The Late Devonian extinction was a series of mass extinction events that occurred during the Late Devonian Epoch, approximately 372 to 359 million years ago. This period saw significant biodiversity loss, with about 19% of all families and 50% of all genera becoming extinct[1][4]. The Kellwasser event, at the Frasnian-Famennian boundary, and the Hangenberg event, at the end of the Devonian, were two major extinction pulses[1][3]. These events primarily affected marine life, with hard-hit groups including brachiopods, trilobites, and reef-building organisms like corals and stromatoporoids[1][3]. The causes of the Late Devonian extinction are still debated but are thought to involve a combination of factors, including climate changes, ocean anoxia, tectonic activity, and possibly impact events[2][3]. Climate fluctuations and anoxia likely played significant roles, as evidenced by the presence of black shales indicative of low oxygen conditions[2][3]. The extinction events had profound impacts on Earth's ecosystems, leading to a permanent change in marine ecosystems and affecting the evolution of terrestrial life[5]. Despite extensive research, the precise triggers remain unclear, with hypotheses ranging from volcanic eruptions to bolide impacts[2][5].