Mass Extinctions on Earth

Throughout the history of earth, there have been five mass extinctions that destroyed most of the life on the planet.  These extinction events have been found by studying fossil records.  During a mass extinction, a sharp decrease in the number of species living on earth occurs.

  1. First Mass Extinction (Ordivician-Silurian Extinction Event)  This mass extinction event occurred around 450 to 440 million years ago.
  2. Second Mass Extinction (Late Devonian Extinction Event)   This mass extinction event occurred around 375 to 360 million years ago.
  3. Third Mass Extinction (Permian-Triassic Extinction Event)   This mass extinction event occurred 251 million years ago. This is the worst recorded extinction period, also known as the Great Dying.
  4. Fourth Mass Extinction (Triassic-Jurassic Extinction Event)    This mass extinction event occurred 205 million years ago.
  5. Fifth Mass Extinction (Cretaceous-Paleogene Extinction Event)    This mass extinction event occurred 65 million years ago.  This extinction caused all dinosaurs to become extinct.
  6. Sixth Mass Extinction (The Holocene Extinction)  This extinction is happening now and is caused by humans.

 

 

 

cosmosmagazine.com
Biologists suspect we’re living through the sixth major mass extinction. Earth has witnessed five, when more than 75% of species disappeared.

 

 

Earth’s five mass extinction events Posted on 15 April 2010 by John Cook. As climate changes, a major question is whether nature can adapt to the changing conditions?

 

https://en.wikipedia.org/wiki/Extinction_event

en.wikipedia.org
An extinction event (also known as a mass extinction or biotic crisis) is a widespread and rapid decrease in the biodiversity on Earth. Such an event is identified by …

 

 

science.nationalgeographic.com
Learn about prehistoric mass extinctions and animal die-offs and get information, facts, and more about dinosaur extinctions from National Geographic.

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