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Skip to content. Twitter Facebook Pinterest Google Classroom. Article Vocabulary. By Hillel J. Our van slowed to a stop in the gentle hills of the Czech Republic. The Black Triangle gets its name from the coal burned by nearby power plants. Decades of acid rain from power-plant emissions have devastated the region's ecosystems. For months I'd been on the trail of the greatest natural disaster in Earth's history.
About million years ago, at the end of the Permian period, something killed off 90 percent of the planet's species. Less than five percent of the animal species in the seas survived. On land nearly all the trees died. Looy had told me that the Black Triangle was the best place today to see what the world would have looked like after the Permian extinction. We saw the first signs of death as we walked into the hills — hundreds of fallen logs lay hidden in the undergrowth.
No birds called, no insects hummed. The only sound was the wind through the weeds. Looy believes that the Permian extinction was caused by acid rain following a massive release of volcanic gases. She is like a homicide detective studying pollen and pine cones for clues about what happened millions of years earlier.
Looy is one of many scientists on the case. They are trying to identify the killer responsible for the largest mass extinction that has struck the planet. To understand this extinction, I wanted to get a sense of its scale — and for that, I had to go to South Africa.
I joined Roger Smith, a paleontologist at the South African Museum, and we drove across a treeless stretch of land known as the Karoo. If we had driven here before the Permian extinction, we would have seen animals as abundant and varied as in today's Serengeti. Most would have belonged to a group known as synapsids.
They looked like a cross between a dog and a lizard, and for more than 60 million years they were Earth's dominant land vertebrates. They filled the same ecological space as their successors, the dinosaurs. Smith slowed, rolled down the window, and pointed to a horizontally banded cliff.
He explains the fossil record here reveals the transition between the Permian and Triassic periods. The fossils embedded in the rock indicate that synapsids took a savage hit at the end of the Permian. Their remains are abundant on the lower layers, but higher up they dwindle and disappear. Plants were also hit by the extinction. To see evidence of the destruction of the world's forests I travel to the Italian Alps. I joined a research team led by Henk Visscher of the University of Utrecht.
We visited exposed fossil beds revealing the transition from the Permian to the Triassic. Here researchers showed me evidence of a great die-off of trees.
The older, lower levels of the fossil record contain a great deal of pollen from conifers from before the extinction event. In rocks from the Permo-Triassic boundary, however, the pollen has disappeared, replaced by fossilized fungi.
As it decays, fungi grow into it from spores on the ground, decomposing it. Visscher's team has found elevated levels of fungal remains in Permo-Triassic rocks from all over the world. But even getting halfway there would be something to be very concerned about. The magnitude of change we are currently experiencing is fairly large. Deutsch added that the only way to avoid a mass aquatic die-off in the oceans was to reduce carbon emissions, given there is no viable way to ameliorate the impact of climate change in the oceans using other measures.
This article is more than 2 years old. A model in the study mimicking conditions in the Permian period suggests marine animals essentially suffocated in the warming waters. Photograph: AP. When Pangaea was finally formed in the middle of the Permian, there was a substantial decrease in the area of shallow marine environments. These shallow environments were the most productive parts of the oceans and produced much of the oxygen on the planet. Without them, the planet may have seen a decrease in the amount of oxygen available.
These areas were also home to many organisms that were the base of food chains. The formation of Pangaea may have also had an effect on ocean circulation which in turn affected nutrient circulation in the oceans, and may have also affected global weather patterns.
Another possible cause of the extinction is an impact event, much like the meteor that famously killed the dinosaurs at the end of the Cretaceous Period. The Permian extinction appears to have happened in two or three pulses of extinction. Two or more separate impacts could have possibly accounted for these pulses.
Some possible evidence for impact events are meteorite fragments in Australia, rare shocked quartz in both Australia and Antarctica, and craters in Australia.
If a meteor did impact Earth during this time, it more than likely landed in the ocean. Since the ocean floor is recycled by tectonic activity every million years, any evidence of the impact is likely gone.
The most likely scenario is that the Permian mass extinction was caused by a combination of many events which together made the Earth unsuitable for most life. It is important for scientists to try to understand the conditions during the Permian mass extinction because it will help them to better understand the climate crisis we are currently facing and possibly help take measures to avoid another mass extinction event in the future.
Encyclopedia Britannica: Permian Period. Encyclopedia Britannica: Permian extinction. Jackson Chambers Writer. All Posts. Julio Lacerda Staff Artist and Writer. Of the five mass extinction events on Earth, the one million years ago during the Permian Period was the most devastating.
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