Great Dying

Definition

The Great Dying refers to a massive and widespread extinction event that occurred around 252 million years ago at the end of the Permian period, resulting in the loss of about 90% of marine species and 70% of terrestrial vertebrate species. This event had profound impacts on biodiversity, reshaping ecosystems and paving the way for new forms of life in the aftermath.

5 Must Know Facts For Your Next Test

1. The Great Dying is considered the largest mass extinction in Earth's history, with estimates suggesting it wiped out approximately 90% of all marine life.
2. The event is thought to have been caused by a combination of volcanic eruptions, climate change, and possibly asteroid impacts, leading to drastic environmental changes.
3. After the Great Dying, ecosystems underwent a significant transformation, allowing for the rise of new species during the Triassic period.
4. The recovery from this mass extinction took millions of years, illustrating the long-lasting impact such events can have on biodiversity and ecosystem dynamics.
5. This extinction event set the stage for the dominance of dinosaurs in subsequent eras, showcasing how mass extinctions can reshape the course of evolutionary history.

Review Questions

• Discuss the main causes of the Great Dying and their relationship to subsequent biodiversity changes.
  • The Great Dying was primarily triggered by volcanic eruptions that led to significant climate shifts, ocean acidification, and anoxic conditions in marine environments. These drastic changes resulted in widespread habitat loss and altered ecosystems, which directly contributed to the massive loss of biodiversity. The aftermath saw a shift in evolutionary paths as surviving species adapted to new conditions, leading to different forms of life emerging during the Triassic period.
• Evaluate the ecological consequences of the Great Dying on both marine and terrestrial ecosystems.
  • The Great Dying had devastating effects on both marine and terrestrial ecosystems. In marine environments, about 90% of species went extinct, leading to significant alterations in food webs and ecological interactions. On land, approximately 70% of terrestrial vertebrates disappeared, resulting in a shift in vegetation types and ecological niches. The reduction in biodiversity opened opportunities for new species to evolve and fill these niches, fundamentally changing ecosystem structures.
• Analyze how the Great Dying influenced evolutionary trends following its occurrence and its relevance to current biodiversity crises.
  • The Great Dying had lasting implications for evolution by allowing new species to dominate post-extinction landscapes. This event paved the way for reptiles, including dinosaurs, to become prominent during the Mesozoic era. Understanding this mass extinction helps us draw parallels to today's biodiversity crises caused by human activities. The lessons learned from how ecosystems recovered after such a catastrophic event can inform conservation efforts aimed at mitigating current threats to biodiversity.

Related terms

Permian-Triassic Extinction: The most severe mass extinction event in Earth's history, marking the boundary between the Permian and Triassic geological periods.

Biodiversity: The variety and variability of life on Earth, encompassing the diversity of species, ecosystems, and genetic variations within species.

Ecological Recovery: The process through which ecosystems rebound and re-establish following a disturbance, such as a mass extinction event.