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• Permian Extinction

  More than 90 percent of all organisms that have ever lived on Earth are extinct
• Extinction


  The termination of an organism or of a group of organisms (taxon), usually a species
• Moment of extinction


  The death of the last individual of the species, although the capacity to breed and recover may have been lost before this point
• Extinction event


  A widespread and rapid decrease in the biodiversity on Earth
• Mass extinction


  An extinction event
• Biotic crisis


  An extinction event
• An extinction event is identified by a sharp change in the diversity and abundance of multicellular organisms
• First mass extinction, 86% of species lost


  444 million years ago
• First mass extinction (End Ordovician)


  • Caused by glaciation and falling sea levels
  • Trilobites, brachiopods, and graptolites died off in large numbers
• Second mass extinction, 75% of species lost

  375 million years ago
• Second mass extinction (Late Devonian)


  • Caused by giant land plants releasing nutrients into the oceans, leading to algal blooms and oxygen depletion
  • Volcanic ash cooling temperatures killed off spiders, scorpions, and amphibious creatures
• Third mass extinction, 96% of species lost

  251 million years ago
• Third mass extinction (End Permian)


  • Caused by volcanic eruptions releasing carbon dioxide and methane, warming the Earth and acidifying the oceans
• Fourth mass extinction, 80% of species lost

  200 million years ago
• Fourth mass extinction (End Triassic)


  • Caused by asteroid impact, climate change, and flood basalt eruptions
• Fifth mass extinction, 76% of all species lost

  66 million years ago
• Fifth mass extinction (End Cretaceous)


  • Caused by a combination of volcanic activity, asteroid impact, and climate change, leading to the extinction of dinosaurs
• Sixth mass extinction (Holocene extinction)


  Present
• Sixth mass extinction (Holocene extinction)


  • Caused by human activities such as habitat destruction, overharvesting, and climate change
• The Holocene extinction is considered the largest extinction event since the Cretaceous-Paleogene extinction that wiped out the dinosaurs
• Current estimates suggest as many as 140,000 species are going extinct each year