We all know that there are "big five" extinction events in Earth history, today I want to focus on the largest extinction of all time, the end-Permian extinction event.
The following images are courtesy to BBC Nature, and some of my own research. First of all, what is Permian? According to BBC Nature, the Permian is defined as the following: Permian period: The Permian started with an ice age and ended with the most devastating mass extinction the Earth has ever experienced. In fact, at least two mass extinctions occurred during this time. It's also when all the continents of the world finally coalesced into one supercontinent, named Pangaea (meaning 'the entire Earth'). As the globe warmed up and the ice retreated, many areas of Pangaea became very arid. The oxygen level plummeted too, from a high of 35% of the total atmosphere to around 15%. For comparison, today's oxygen content is 21%. (I have doubts about the above assertion of oxygen levels, more information on Late Permian oxygen levels, see my recent work on oxygen during the end-Permian mass extinction, an Earth system modeling perspective). The webpage for the images below is: http://www.bbc.co.uk/nature/history_of_the_earth/Permian#intro
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Ying CuiI'm a geoscientist doing research on extreme environmental change and its impact to biodiversity in the geologic past. ArchivesCategories |