The history of the Late Ordovician mass extinction, the first one in history
It was almost twice as deadly as the mass extinction that killed the dinosaurs. 85% of marine species on Earth were eliminated during this extinction. It was the first one, and it's the second most severe to date. It occurred more than 440 million years ago (mya). The Late Ordovician mass extinction, also known as the Ordovician-Silurian or the end-Ordovician mass extinction, destroyed the 49-60% of marine genera and the 85% of marine species. Only the Permian-Triassic killed more species -it's not known as the Great Dying for no reason!-. But how did the first ever mass extinction happen? Let's discover it. As its own name indicates, this event occurred between the late Ordovician and the early Silurian period. There were two different phases or pulses in the extinction. The first pulse began roughly as the same time as the Hirnantian stage, the last of the Ordovician Period, 445.2 mya. What happened was a major drop in temperatures -possibly caused by a descent in carbo...