1. The Ordovician-Silurian Extinction
439 million years ago
Didn’t ordovician period, most life on earth lived in the sea. A sudden drop in sea levels occurred as glaciers formed, and a sudden rise in sea levels are god is glaciers melted. This dramatically impacted sea dwelling creatures, causing about 25% of marine families and 60% of marine genera to die.
The Late Devonian Extinction
364 million years ago
During this extinction event much of the sea but became the word of oxygen, making it inhospitable for anything except bacteria. Scientist think that new plant species caused the climate change, with significantly contributed to the massive loss of life. Notably the event may have been characterized by series of extensions over several million years, rather than a single event. Three quarters of a species died.
The Permian Triassic Extinction
215 million years ago
The permian mass extinction has been nicknamed “The Great Dying” since a staggering Instagram 96% of species disappear. This means that all life on Earth is descended from the 4% of species that survive. Although direct evidence has yet to be found, the primary hypothesis is that an impact event caused just to cover the Earth, which cause a significant loss of oxygen.
The End Triassic Extinction
199 – 214 million years ago
Scientists that this event was most likely caused by massive floods of lava erupting from the central Atlantic magmatic province, triggering the breakup of pangaea and the opening of the Atlantic ocean the volcanism may have led to deadly global warming.
The Cretaceous-Tertiary Extinction
65 million years ago
Also known as the K/T extinction, this is the famed event that led to the death of the dinosaurs. However, many other organisms also be perished at the end of the Cretaceous, including the ammonites, many flowering plants, and the last of the pterosaurs. It was caused by the impact of a several-kilometre-wide by asetroid which created the Chicxulub crater that is on the Yucatan Peninsular and beneath the gulf of Mexico.