The Permian extinction event taken place some 250 million years ago is believed to have extirpated all life forms due to massive volcanic eruption and devastating global warming. Well, a newly excavated fossil site in south-west China seems to have an astonishing tale to tell. Investigators from the Chengdu Geological Center in China claim that the fossil site sheds light on the possible way planet Earth recovered from the mass extinction.
When extinction took place one in ten species apparently survived and formed the basis for the recovery of life in the subsequent time period, known as Triassic. If the fossil site at Luoping in Yunnan Province is to be believed then, a fully-functioning ecosystem was developed after around 10 million years. Researchers assume that the bottom of the food chains was dominated by species typical of later Triassic marine faunas such as crustaceans, fishes and bivalves. It now seems that these species were different from the preceding ones.
Professor Mike Benton, in the School of Earth Sciences, added. “The Luoping site dates from the Middle Triassic and contains one of the most diverse marine fossil records in the world. It has yielded 20,000 fossils of fishes, reptiles, shellfish, shrimps and other seabed creatures. We can tell that we’re looking at a fully recovered ecosystem because of the diversity of predators, most notably fish and reptiles. It’s a much greater diversity than what we see in the Early Triassic – and it’s close to pre-extinction levels.”
Top predators presumably were the long-snouted bony fish Saurichthys, the ichthyosaur Mixosaurus, the sauropterygian Nothosaurus and the prolacertiform Dinocephalosaurus. These predators apparently fed on fishes as well as small predatory reptiles. The fossils provide a detailed insight into the recovery and development of marine ecosystems after the end-Permian mass extinction. Investigations will be continued to understand the way life reasserted itself after the most catastrophic global event in the history of this planet.
The research was published in the Proceedings of the Royal Society B.