O mundo já acabou 5 vezes (e você não sabia) | Flavio Pretto | TEDxUFSM

Quick Overview

The world has not ended five times, contrary to popular belief derived from media interpretations of ancient predictions, but the Permian-Triassic extinction event, known as "The Great Dying" approximately 252 million years ago, was the most severe extinction in Earth's history, wiping out 96% of marine life and 70% of terrestrial vertebrates, caused by massive volcanism that expelled massive amounts of CO2, leading to global warming, ocean acidification, and desertification.

Key Points: The speaker refutes the idea that the world ended five times based on popular media interpretations, specifically referencing the Mayan calendar prediction of 2012. The most catastrophic event was the Permian-Triassic (P-Tr) extinction, or "The Great Dying," occurring about 252 million years ago. The P-Tr extinction impacted the planet globally, resulting in the extinction of 96% of marine life and 70% of terrestrial vertebrates. The primary cause cited for this mass extinction was massive volcanism in Siberia, which released significant amounts of greenhouse gases, notably CO2, into the atmosphere. This volcanism led to global warming, ocean acidification, and widespread desertification, creating an inhospitable environment. Survivors of the P-Tr extinction, such as small reptiles and early archosaurs (ancestors of crocodiles and birds), were able to endure the catastrophe because they were small, adapted, and not dominant herbivores. Fossils of these survivors, including small synapsids and archosaurs found in the Rio Grande do Sul region, demonstrate their ability to persist through environmental crises.

Context: Flávio Pretto, a paleontologist from UFSM (Federal University of Santa Maria), delivers a TEDx talk discussing mass extinction events, contrasting popular misconceptions (like the Mayan calendar prediction) with the scientific reality of the Permian-Triassic extinction event, the largest in Earth's history. He uses paleontological evidence, particularly fossils found in Southern Brazil, to illustrate the severity of past catastrophes and discuss the characteristics of the few organisms that managed to survive and eventually diversify.