Permian Triassic Extinction Quiz: The Great Dying and Its Causes

The "Great Dying" was the most severe mass extinction in Earth's history. Nearly all marine life and roughly 70% of terrestrial vertebrate species vanished, nearly ending life on Earth and clearing the way for the rise of the dinosaurs.

The Siberian Traps was a period of immense volcanic activity that lasted for about a million years. It released massive amounts of lava and greenhouse gases, causing catastrophic climate change and ocean acidification.

This is false. While the K-Pg extinction (dinosaurs) is more famous, the Permian-Triassic event was significantly more lethal, earning its nickname "The Great Dying" due to the near-total collapse of global ecosystems.

As the Siberian Traps released CO2, the oceans absorbed much of it, forming carbonic acid. This made it difficult for marine organisms like corals and brachiopods to build shells, while the warming water held less dissolved oxygen.

The volcanic activity triggered a "runaway" greenhouse effect. Warming oceans released methane from the seafloor, further heating the planet and causing the oceans to lose oxygen, which suffocated most marine life.

Trilobites were incredibly successful and diverse throughout the Paleozoic Era. However, the extreme environmental shifts of the Permian-Triassic event finally wiped out the remaining lineages of these iconic armored creatures.

True. Mass extinctions function as a "reset button." By clearing out dominant Permian groups like the paramammalian therapsids, new ecological niches opened up, eventually allowing dinosaurs to dominate the Triassic period.

As global temperatures soared, the oceans warmed up. Warmer water cannot hold as much dissolved oxygen as cold water. This, combined with disrupted ocean currents, created "dead zones" where most marine animals simply could not breathe.

Some scientists believe that anoxic bacteria in the stagnant oceans produced massive amounts of hydrogen sulfide gas (H2S). This toxic gas may have bubbled out of the ocean, poisoning land animals and damaging the ozone layer.

Surviving organisms were typically those that could tolerate low oxygen or high CO2 levels. Lystrosaurus, a burrowing herbivore, became the most common land vertebrate after the event because it was adapted to harsh conditions.

The "Great Dying" serves as the definitive boundary between the Paleozoic Era ("Ancient Life") and the Mesozoic Era ("Middle Life"). It was the largest turning point in the history of the Phanerozoic Eon.

Because the extinction was so thorough and the environmental damage so extreme, it took approximately 10 million years for complex ecosystems to fully recover and for biodiversity to reach its previous levels.

Initial warming from volcanic CO2 likely melted methane ice on the seafloor. Methane is a much more potent greenhouse gas than CO2, so its release created a feedback loop that pushed global temperatures to lethal levels.

Ocean acidification occurs when CO2 reacts with seawater. This reduces the availability of carbonate ions, which organisms like corals and mollusks need to build their shells, causing their protective structures to weaken or dissolve.

The Siberian Traps are visible today as massive layers of volcanic rock called "flood basalts." Chemical signatures in these rocks and surrounding sediments confirm the massive release of gases that matches the timing of the extinction perfectly.