A mass extinction 233 million years ago reshaped life on Earth, allowing dinosaurs to take over, according to scientists.
The event, which has been named the Carnian Pluvial Episode, is said to have been caused by a sudden change in climate.
A team of 17 scientists reviewed geological and palaeontological evidence, finding that massive volcanic eruptions in western Canada are the most likely cause of the event.
These eruptions led to large volumes of volcanic basalt rocks pouring out and forming what is now the western coast of North America.
The climate warming has been linked to an increase in rainfall at the time – this was first identified as a humid episode lasting a million years by geologists in the 1980s.
Despite large parts of life being wiped out both in the ocean and on land, the event allowed dinosaurs to take over the planet – they existed 20 million years before but were rare and unimportant.
Researchers have also said the event led to more modern ecosystems forming with conifer forests, as well as some of the first mammals – turtles, crocodiles and lizards appearing and diversifying during this time.
Professor Jacopo Dal Corso, from the China University of Geosciences in Wuhan, said: “The eruptions were so huge, they pumped vast amounts of greenhouse gases like carbon dioxide, and there were spikes of global warming.”
He explained that up to now, five significant mass extinctions have been identified over 500 million years of history, saying they’ve all “had a profound effect on the evolution of the Earth and of life”.
He added: “We have identified another great extinction event, and it evidently had a major role in helping to reset life on land and in the oceans, marking the origins of modern ecosystems.”
The researchers have also suggested that the Carnian Pluvial Episode affected ocean life, seeing the beginnings of modern-style coral reefs, as well as many of the modern groups of plankton.