How the 'Great Dying' wiped out plants first? Researchers find answer

Smoke rises from the Pu'u O'o vent on the Kilauea Volcano October 29, 2014 on the Big Island of Hawaii.
Representational picture Reuters

A group of researchers claimed that the world's largest extinction wiped out 90 percent of all plants before many animals counterparts almost 250 million years ago.

The earth-spanning cataclysm, also known as 'The Great Dying' killed off plants up to 400,000 years prior to the extinction of ancient animals and marine species. It happened when the planet's continental crust mashed into the supercontinent, Pangaea, volcanoes in modern-day Siberia began erupting.

The eruption which caused the release of carbon and methane into the atmosphere for almost two million years helped to extinguish almost 96 percent of marine life and 70 percent of land-based vertebrates.

But, as per the new study, published in the journal Nature Communications conducted by the University of Nebraska-Lincoln, the team of the researchers suggested that the nickel byproduct from a volcanic eruption started wiping out some Australian plants before most marine species.

The lead author of this study, Christopher Fielding said, "That's big news. People have hinted at that, but nobody's previously pinned it down. Now we have a timeline."

The research team studied fossilized pollen, as well as the chemical composition and age of rock, including the layering of sediment on the cliff-sides of the south-eastern part of Australia. During the research, they also found high concentrations of nickel in the Sydney Basin's mud-rock and it was surprising because there are no local sources of such elements.

This led the team to the conclusion of the study and Tracy Frank, professor and chair of Earth and atmospheric sciences said that the findings point to the eruption of lava through nickel deposits in Siberia.

She also stated that the volcanism could have converted the nickel into an aerosol that drifted thousands of miles southward before poisoning and killing much of the plant life there and she added that similar spikes in nickel have been found in other parts of the world.

Researchers believe that the phenomena may have caused a series of others such as herbivores dying from the lack of plants, carnivores dying from a lack of herbivores and release of toxic sediment into seas already reeling from rising carbon dioxide, acidification and temperatures.

Frank said that the emerging similarities, mostly between the spikes in greenhouse gases and the continuous disappearance of species, make it a lesson worth studying.

She added that "Looking back at these events in Earth's history is useful because it lets us see what's possible. How has the Earth's system been perturbed in the past? What happened where? How fast were the changes? It gives us a foundation to work from - a context for what's happening now."

In 2018, researchers found that the Flood Basalts eruption caused the disappearance of a large proportion of life on Earth.