3.5. It was just one of the five largest mass extinctions the planet has experienced since the evolution of living things billions of years ago, and it was not the worst.
Now, scientists say they have identified evidence of a new mass extinction in the fossil record, and it is one that allowed dinosaurs to dominate the earth for more than 200 million years.
It took place 232 million to 234 million years ago and this is called the corneal pleural episode.
“So far, paleontologists have identified five ‘large’ mass extinctions in the 500 million years of life history,” said the study’s co-author. Geographer Jacopo de la Corso of the University of Geosciences at Wuhan said in a statement.
“Each of these had an impact on the evolution of the earth and life. We have identified another great extinction phenomenon, and clearly played a key role in helping to restore life on its land and in the oceans, marking the origins of modern ecosystems.”
The researchers said that now most of the volcanic eruptions were caused in western Canada, where huge amounts of volcanic basalt were poured and eventually formed much of the west coast of North America.
“The eruption was so huge, they used huge amounts of greenhouse gases like carbon dioxide, and there were spikes of global warming,” Dal Corso said.
Climate change caused great damage to biodiversity at sea and on land. After the extinction, new groups took over, forming more modern-like ecosystems. Climate change has promoted the growth of plant life and the expansion of coniferous forests – mostly evergreen trees that we know today by needles and cones.
It wasn’t just dinosaurs. Many modern groups of plants and animals also appeared at this time, including the first turtles, crocodiles, lizards and the first mammals.
The study, published in the journal Scientific Advances, found that arn 33% of marine life was affected by the Carnian Pluvial episode, along with marine life. It marks the beginning of the type of coral reef we see today, as well as the beginning of many modern groups of plankton, indicating a profound change in ocean chemistry after mass extinction.
Warm weather was also associated with increased rainfall, and this lasted about 1 million years together in a humid episode in the 1980s. “It was the sudden dry conditions after the humid episode that gave the dinosaurs their chance,” said study co-author Mike Benten, Professor of Vertebrate Paleontology at the University of Bristol in the United Kingdom.
“We now know that dinosaurs originated about 20 million years before this event, but it remained very rare and significant until the Carnian Pluvial episode hit,” Benten said.
Alfio Alessandro Chiarenza, a paleontologist and research collaborator at University College London, said that while highlighting the many important changes taking place in life during this period, he was “careful to define this as mass extinction.”
“Given the disparity in fossil record, our information about trends in biodiversity by time and space is often ambiguous,” he said by email.
He added, “Remains we may not have investigated yet or may not be able to save in our days may be‘ hidden ’in rocks.
Scientists generally define mass extinction as the disappearance of at least 50% of all species in a short period of time. Geographically, that period Usually less than 2.8 million years.
Benten told CNN that he still could not estimate the figures for the loss of terrestrial life, but that the event would have affected plants and animals of a variety of ecology around the world, with significant species loss in the short term.
The worst mass extinctions occurred 250 million years ago, with 95% of all species being wiped out and large-scale volcanic eruptions in Siberia.
.
