The Permian-Triassic extinction event occurred 251 million years ago. This is the worst recorded extinction period, also known as the Great Dying.  During this period, 96% of all marine species and 70% of all terrestrial vertebrate species became extinct.   All types of life forms were affected including marine life, plants and terrestrial invertebrates and vertebrates.  Due to the magnitude of the loss of life during this extinction period, Earth took a significantly longer period of time to recover than other mass extinctions.  It is estimated that earth may have taken 10 million years to get back to a healthy biodiversity.  This extinction period is related to some sort of catastrophic event such as a meteor impact, increased volcanic activities, or sudden methane release from the ocean floor.

Permian extinction – National Geographic science.nationalgeographic.com Read a National Geographic magazine article about the mass extinction at the end of the Permian period and get information, facts, and more about the Permian and …

BBC Nature – Permian mass extinction videos, news and facts http://www.bbc.co.uk Permian mass extinction. The Permian mass extinction has been nicknamed The Great Dying, since a staggering 96% of species died out. All life on Earth today is …

The Great Dying | Science Mission Directorate science.nasa.gov January 28, 2002: It was almost the perfect crime. Some perpetrator — or perpetrators — committed murder on a scale unequaled in the history of the world.

Evolution: Library: Permian-Triassic Extinction – PBS http://www.pbs.org Permian-Triassic Extinction: One of the most dramatic and mysterious events in the history of life, the so-called “Great Dying” of animals and plants some 250 million …