Duration and Timing of The Extinction Events
Extinction rates appear to be higher than the background rate for an extended period lasting the last 20–25 million years of the Devonian. During this period, about eight to ten distinct events can be seen, of which two stand out as particularly severe. The Kellwasser event was preceded by a longer period of prolonged biodiversity loss. The fossil record of following first 15 million years of the Carboniferous is largely void of terrestrial animal fossils, likely related to losses during the end-Devonian Hangenberg event. This period is known as the Romer's gap.
Read more about this topic: Late Devonian Extinction
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