A recent study found evidence that previously extreme global warming had wiped off most forms of life on Earth as the species couldn't bear the heat. Scientist worry this may happen again.
About 252 million years ago, Earth was on the verge of experiencing a mass extinction called the end-Permian event. This was because of extreme global warming. The Earth's surface was heating up above bearable temperatures and life near the Equator was struggling to survive.
Researchers have found that hot ocean surface waters reaching more than 104 degrees Fahrenheit left Earth a virtual wasteland.
"We may have found the hottest time the world has ever had," researcher Paul Wignall, a geologist at the University of Leeds in England, told LiveScience.
After the end-Permian mass extinction came a time "called the 'dead zone,'" Wignall said. "It's this 5-million-year period where there's no recovery, where there is a very low diversity of life. We had to go through several tons of rock to look at tiny conodont fossils.
"People always thought the end-Permian extinctions were related to temperature increases, but they never measured the temperature then in much detail before, since it involves a lot of hard work looking at these microfossils."
Wignall further explained.
"Photosynthesis starts to shut down at about 35 degrees C [95 degrees F], and plants often start dying at temperatures above 40 degrees C [104 degrees F]," Wignall said. "This would explain why there's not much fossil record of plants at the end-Permian- for instance, there are no peat swamps forming, no coal-forming whatsoever. This was a huge, devastating extinction.
"I'm sure there will be questions as to whether sea-surface temperatures really did get this extreme. But I think extreme temperatures would explain quite a lot with the fossils we see showing major losses of animal and plant life."
These findings and the case of global warming that has been taking place currently has lead to the raising of the question, "could this happen again".
According to Wignall, "In theory, it could." But the scientist assures all that though global warming is a posing problem that needs to be addressing seriously and immediately, Earth is far from reaching conditions as severe as extinction.
"We're not going to get anywhere near the level seen after the end-Permian," Wignall said. "We need to worry about global warming, but it's not going to get to this stage."