The largest extinction in Earth’s history marked the end of the Permian period, some 252 million years ago. Long before dinosaurs, our planet was populated with plants and animals that were mostly obliterated after a series of massive volcanic eruptions in Siberia.
Fossils in ancient seafloor rocks display a thriving and diverse marine ecosystem, then a swath of corpses. Some 96 percent of marine species were wiped out during the “Great Dying,” followed by millions of years when life had to multiply and diversify once more.
What has been debated until now is exactly what made the oceans inhospitable to life – the high acidity of the water, metal and sulfide poisoning, a complete lack of oxygen, or simply higher temperatures. MORE
Header image: This fossilised spiralling shark tooth is from the Helicoprion, an unusual shark that lived during the Permian. The tooth whorl was located inside the shark’s lower jaw. The fossil is on display at the Idaho Museum of Natural History. Credit: James St. John/Flickr.