Mega Eruptions Killed off Ancient Life

By Selina Haefeli

Worldwide volcanic eruptions caused mass extinction of plants and animals 200 million years ago.

Over the history of life on our planet dramatic global events such as ice ages, meteorites crashing into the Earth and climate changes have caused the mass extinction of most creatures around at the time. Not just the dinosaurs were victims of such events: in fact there have been five major catastrophes in the past 540 million years that have led to worldwide major extinction.

One of the “big five” took place at the end of the Triassic period, 200 million years ago. Over half of the life on Earth perished due to the devastating event, which cleared the way for dinosaurs to dominate the Earth for the next 135 million years. Scientists have not been entirely sure what caused the end-Triassic extinction, however, some researchers from the Massachusetts Institute of Technology (MIT) and Columbia University in the United States have recently determined that volcanoes are the main culprits.

In their study published in Science Express the researchers show that large-scale volcanic eruptions occurred at precisely the same time that land and marine species disappeared from the fossil record. They go on to explain that it was not the eruptions themselves that killed off animals and plants but the extremely high amounts of carbon dioxide (CO2) and other gases that got released into the atmosphere and affected the Earth’s environment.

The researchers think there could be an important lessons to be learnt from this study. “In some ways, the end-Triassic-extinction is analogous to what’s happening today… It’s operating on a similar time scale,” said lead author of the study, Terrance Blackburn, to ABC News. “We can gain an insight on the future impact of increasing atmospheric carbon-dioxide levels on global temperatures, ocean acidity and life, by studying the geologic record.”

Source: [MIT News]

Did you know?

Of all the species that have ever existed on Earth 98 percent of them are now extinct.