The Great Permian Extinction

Definition

The Great Permian Extinction was a massive global extinction event that occurred approximately 252 million years ago, leading to the loss of around 90% of marine species and 70% of terrestrial vertebrate species. This event marked the boundary between the Permian and Triassic periods and had profound effects on the evolution of life on Earth, reshaping ecosystems and paving the way for the dominance of dinosaurs in the Mesozoic era.

5 Must Know Facts For Your Next Test

1. The Great Permian Extinction is considered the largest extinction event in Earth's history, leading to dramatic shifts in biodiversity.
2. Various factors contributed to this extinction event, including volcanic eruptions, climate change, and changes in ocean chemistry.
3. The Siberian Traps, a vast region of volcanic rock, is often associated with the events that triggered the Great Permian Extinction due to its massive release of carbon dioxide and other gases.
4. After this extinction, recovery took millions of years before ecosystems fully stabilized, allowing new groups of organisms to thrive.
5. The end of the Permian marked a significant transition in Earth's history, allowing for the rise of reptiles and the eventual dominance of dinosaurs in subsequent periods.

Review Questions

• What were some major factors that led to the Great Permian Extinction, and how did they impact biodiversity?
  • The Great Permian Extinction was driven by several major factors, including extensive volcanic activity from the Siberian Traps, which released vast amounts of carbon dioxide and sulfur dioxide into the atmosphere. This caused severe climate change, including global warming and ocean acidification. These environmental changes devastated marine ecosystems and led to significant declines in biodiversity both in oceans and on land, causing a dramatic restructuring of life on Earth.
• Discuss how the configuration of Pangaea may have influenced the events leading up to the Great Permian Extinction.
  • The formation of Pangaea during the late Paleozoic era had profound effects on Earth's climate and biodiversity. As a single landmass, Pangaea altered ocean currents and weather patterns, which may have contributed to widespread environmental stress. The resulting changes in habitat availability likely made ecosystems more vulnerable to external pressures like volcanic eruptions and climatic shifts. Therefore, Pangaea's configuration played a key role in setting the stage for the mass extinction that followed.
• Evaluate the long-term impacts of the Great Permian Extinction on subsequent evolutionary trends during the Triassic period.
  • The Great Permian Extinction dramatically reshaped life on Earth and set the stage for new evolutionary trends during the Triassic period. The dramatic reduction in biodiversity allowed for adaptive radiation among surviving species, leading to the emergence of new life forms such as early dinosaurs and mammals. This period of recovery created ecological niches that were previously filled by extinct organisms, thus facilitating evolutionary innovation. The consequences of this extinction event were long-lasting, influencing which species would dominate in later eras.

Related terms

Mass Extinction: A widespread and rapid decrease in biodiversity on Earth, characterized by the extinction of a large number of species in a relatively short period.

Pangaea: The supercontinent that existed during the late Paleozoic and early Mesozoic eras, consisting of nearly all of Earth's landmasses, which affected climate and sea levels.

Triassic Period: The geological period following the Permian Extinction, marking the beginning of the Mesozoic Era and featuring the emergence of dinosaurs and mammals.