A recent investigation revealed an unknown mass extinction happened before the appearance of dinosaurs. It was a violent series of volcanic explosions that occurred 233 million years ago. Composed of carbon dioxide, water vapor, and methane, these explosions created unprecedented global warming.
Just before the age of the dinosaurs, a mass extinction event changed the composition of the planet. Extinguishing most of the dominant tetrapods, this newly discovered event was part of a series of mass extinctions that created the world we know today.
According to geologists and paleontologists, there have been five mass extinctions in Earth’s history (at least, that is so far what research indicates). The Cretaceous mass extinction, which put an end to the existence of dinosaurs, is known as the last such event. However, until now, the event that led to the appearance of dinosaurs was unknown.
Referred to as the Carnian pluvial episode, this event was characterized as the cause of unprecedented global warming on Earth before the dinosaurs arose. Through intense volcanic explosions, the Earth’s soil and the environment became so hot that they caused a massive die-off.
Marine and terrestrial ecosystems changed intensely as the Earth warmed and dried out. Plants and herbivores experienced a decline, as did herbivorous tetrapods or dicynodonts. However, this prehistoric global warming was not enough to annihilate life. Experts say this episode set the stage for the age of the dinosaurs.
After the explosions, these immense animals found a new foothold, and from then on, their existence lasted about 165 million years. Turtles, lizards, other mammals, crocodiles, and some modern tetrapods found the revolution of life and grew. This is how the Carnian pluvial episode triggered a new stage on Earth.
How was this unknown mass extinction discovered?
In 1980, a group of European geologists discovered that the seafloor had undergone a major change some 232 million years ago. Then, geologist Jacopo dal Corso identified a coincidence between a peak of eruptions of the Wrangellia basalts and the pluvial episode.
Finally, the review of Triassic rocks, plus a trace of the Carnian pluvial episode in South America, North America, Australia, Asia, and Europe, proved that the pre-dinosaur mass extinction did occur. But what exactly happened in the Carnian pluvial episode?
According to experts, this event involved five volcanic eruptions that pumped carbon dioxide, methane, and water vapor into the atmosphere to cause global warming.
This event produced precipitation all over the world, which was accompanied by acid rain. The Earth was covered in dilute acid, which caused the oceans to acidify. Life died, but as time passed, the balance was restored, and a multitude of incredible organisms re-emerged: the mighty dinosaurs!
Text courtesy of Ecoosfera
Photos: Unsplash: Jon Butterworth / Markus Spiske
Translated by María Isabel Carrasco Cara Chards
