EARTH Magazine: When Earth Hit the Reset Button on Life
From EARTH Magazine, November 3, 2016 -- The Permian-Triassic extinction event wiped out 96% of all marine life and at least 75% of terrestrial life. It is the largest of the "Big Five" extinction events in Earth history, and it defined the boundary between the Paleozoic and the Mesozoic geologic eras. EARTH Magazine explores new research on the "P-T" mass extinction to look at what caused it, and how it can inform our understanding of today's ongoing extinction event.
The trouble started when flood basalts erupted in what is now Siberia some 252 million years ago and didn't stop for approximately a million years. These eruptions released massive quantities of gas into the atmosphere; the greenhouse effect quickly heated the planet. What is known is that whole ecosystems both in the oceans and on land began to topple like dominos.
Scientists are still busy refining this narrative. With more data and the discovery of new usable outcrops from study sites in China to South Africa, researchers hope to more concisely figure out the timing and the exact causes of this extinction event. Did climate change, ozone loss and/or ocean acidification kill off Permian fauna? Did the extinctions occur throughout the entire million years of the eruption, or during a shorter period of thousands of years? Was the massive Siberian eruption the only driver of this extinction event? Explore the latest research on this tumultuous time in the planet's history in EARTH Magazine: http://www.earthmagazine.org/article/when-earth-hit-reset-button-life-ne...
The November issue of EARTH Magazine is now available. It includes stories on the discovery of a new type of meteorite found in Sweden, new insight into the electric fields of dust storms and what this means for Mars research, and new research on the paleontological conundrum of the turtle that suggests their shells evolved for burrowing, not protection. To explore more about the science of our planet visit www.earthmagazine.org.