Huge volcanic eruptions caused the largest mass extinction in history, scientists believe. The last Permian extinction, also known as the Great Dying, devastated life on Earth when it took place 250million years ago. It saw 95 per cent of sea life wiped out and 70 per cent of animals on land killed.
While it is widely accepted that a meteorite was at least the partial cause for ending the dinosaur era 65million years ago, it was unclear what led to the earlier, more severe extinction.
The location of volcanoes, known as the Siberian Traps, are now found in northern Russia, centred around the city of Tura and also encompass Yakutsk, Noril’sk and Irkutsk. They cover an area just under two million square kilometres, a size greater than that of Europe.
The ash plumes from the volcanoes travelled to regions now in Canada’s Arctic where coal ash layers were found.
Previous research had suggested massive volcanic eruptions through coal beds in Siberia generated significant greenhouse gases that in turn caused runaway global warming.
Now scientists from the University of Calgary believe the most violent volcanic eruption in history to be the reason behind the extinction.
They cite the discovery of layers of coal ash in rocks from the extinction boundary in Canada’s High Arctic as the first direct proof to support this.
Dr Steve Grasby said: ‘This could literally be the smoking gun that explains the latest Permian extinction.
‘Our research is the first to show direct evidence that massive volcanic eruptions – the largest the world has ever witnessed – caused massive coal combustion thus supporting models for significant generation of greenhouse gases at this time.’
At the time of the extinction, Earth contained one big land mass, a super-continent known as Pangaea. The environment ranged from desert to lush forest.
Four-limbed vertebrates were becoming more diverse and among them were primitive amphibians, early reptiles and synapsids – the group that would, one day, include mammals.