Life on earth has been assaulted multiple times over its long history, by vicious mass extinctions and crashes in biodiversity. The most devastating of these was The Great Dying, a mass extinction that occurred 252 million years ago, at the end of the Permian.
A new study published in Proceedings of the Royal Society B details how life recovered from The Great Dying (approximately 251.9 million years ago), in comparison with two flanking smaller extinction events: the Guadalupian–Lopingian (273mya) and Triassic–Jurassic (201.3 may) mass extinctions.
The team, comprised of researchers from the China University of Geosciences, the California Academy of Sciences, the University of Bristol, Missouri University of Science and Technology, and the Chinese Academy of Sciences, demonstrated that The Great Dying was harsher than any other extinction event, with 19 out of every 20 species lost, and sought to explain why species took so much longer to recover.
“We found that the end-Permian event was exceptional in two ways,” says Professor Mike Benton from the University of Bristol. “First, the collapse in diversity was much more severe, whereas in the other two mass extinctions there had been low-stability ecosystems before the final collapse. And second, it took a very long time for ecosystems to recover, maybe 10 million years or more, whereas recovery was rapid after the other two crises.”
To explore why this event was so exceptionally damaging to biodiversity, lead author and Academy researcher Yuangeng Huang reconstructed food webs for a series of 14 life assemblages.
“By studying the fossils and evidence from their teeth, stomach contents, and excrement, I was able to identify who ate whom,” says Huang.
The creatures ranged from plants, molluscs and insects living in ponds and rivers to half-tonne herbivores with tiny heads. By detailing their food webs, the team were able to deduce the impact of wiping out certain species on the rest of the food chain, and shed light on the unique destructiveness of The Great Dying.