The Great Permian Extinction

Trilobite fossil image with a plot of number of Trilobite families as a function of millions of years ago. Last Trilobite family was extinct about 250 million years ago.More than 250 million years ago, when the current continents formed a single land mass, known as the Pangea and there was one super-ocean called Panthalassa, something extraordinary happened. Nearly all life on Earth was wiped out. Over 90% of all marine species and over 70% of terrestrial species went extinct; only their fossils remained to tell us the story.

This so-called Great Permian Extinction, or Great Dying, marked the end of the Permian period and the beginning of the Triassic period in the natural history of the Earth. It was the most devastating extinction, shadowing even the Cretaceous-Tertiary one 65 million years ago when a giant meteor hit the Earth and caused the extinction of the Dinosaurs. Most species, however, did not disappear from the face of the Earth over-night. There was a gradual dying-off over thousands or even millions of years.

The Trilobites, for example, were extremely successful marine life forms at the time. In total, over 150 families and 15,000 species of these hard-shelled, thumb-sized creatures existed. The number of families, as you can see from the plot in the image, started dying off about 450 million years ago. The last remaining family of Trilobites however disappeared abruptly about 250 million years ago. A similar pattern can be seen in the extinction of some other species as well. So what could have caused this? Scientists believe it was a combination of volcanic activity spilling out tons of dust and greenhouse gases into the atmosphere and into the ocean; and then a meteor, the size of Mount Everest, hitting the Earth and spilling massive amounts of sulfur-related compounds into the ocean. What a way to go: first you get suffocated, poisoned and burned for thousands or millions of years, just to be finished off with a big sulfur-carrying meteor. Hell of Earth.

About the Author

Anton Skorucak, MS

Anton SkorucakAnton Skorucak is a founder and publisher of Anton Skorucak has a Master of Science (MS) degree in physics from the University of Southern California, Los Angeles, California and a B.Sc. in physics with a minor in material science from the McMaster University, Canada. He is the president and creator of, a comprehensive physics and astronomy online education, research and reference web site.