What is the Triassic-Jurassic Extinction Event?
The Triassic-Jurassic extinction event, which occurred worldwide 200 million years ago, is one of five major mass extinctions throughout the last 600 million years. The extinction wiped out 20% of marine families, 30% of marine genera, many therapsids (formerly called “mammal-like reptiles”, although they are neither), all large crurotarsans (non-dinosaur archosaurs, ancestors of modern-day crocodiles, alligators, and gavials), and most large amphibians, which up until that point had been the dominant terrestrial fauna. It is estimated that 50% of all species went extinct. Some paleontologists call the Triassic-Jurassic extinction the second greatest mass extinction of prehistory. It occurred in the blink of a geological eye, over no more than 10,000 years. The Triassic-Jurassic extinction came just 50 million years after the greatest extinction event in the era of animal life, the Permian-Triassic extinction of 250 million years ago. The first mass extinction of the Mesozoic era, the
