Fossil discovery reveals complex ecosystems existed on Earth much earlier than previously thought

[rangerrebew]

NEWS RELEASE 9-FEB-2023
Fossil discovery reveals complex ecosystems existed on Earth much earlier than previously thought

Discovery challenges understanding of how quickly life recovered from the greatest mass extinction in Earth’s history

Peer-Reviewed Publication
MCGILL UNIVERSITY
 

CREDIT: XU DAI

About 250 million years ago, the Permian-Triassic mass extinction killed over 80 per cent of the planet's species. In the aftermath, scientists believe that life on earth was dominated by simple species for up to 10 million years before more complex ecosystems could evolve. Now this longstanding theory is being challenged by a team of international researchers – including scientists from McGill University and Université du Québec à Montréal.

A fossilized ocean ecosystem
Until now, scientists have long theorized that scorching hot ocean conditions resulting from catastrophic climate change prevented the development of complex life after the mass extinction. This idea is based on geochemical evidence of ocean conditions at the time. Now the discovery of fossils dating back 250.8 million years near the Guizhou region of China suggests that complex ecosystems were present on Earth just one million years after the Permian-Triassic mass extinction, which is much earlier than previously thought.

“The fossils of the Guizhou region reveal an ocean ecosystem with diverse species making up a complex food chain that includes plant life, boney fish, ray-finned fish, crabs, lobsters, shrimp, and molluscs. In all, our team discovered 12 classes of organisms and even found fossilised faeces, revealing clues about the diets of these ancient animals,” says Morgann Perrot, a former postdoctoral researcher at McGill University, now at Université du Québec à Montréal.

Challenging an age-old theory

https://www.eurekalert.org/news-releases/979313

[Smokin Joe]

What makes these ecosystems any more complex than say, those of the Silurian, with Eurypterids, prey animals, bottom feeders, and the plant flora and microfauna those fed on, or for that matter, those in the Devonian where fish and early land animals and plants were known to be in the mix?
If some 90% of the species on earth went extinct at the Permian-Triassic boundary, surely there was a complex ecology present.
I must note later papers all seem to focus on the great grant magnet of "climate change", but earlier ones had a more distant source for the extinction, one which is at least equally plausible, even if it doesn't keep the money rolling in. To wit:

Impact Event at the Permian-Triassic Boundary: Evidence from Extraterrestrial Noble Gases in Fullereneshttps://www.science.org/doi/10.1126/science.1057243

That great die-off may have been caused by something no more exotic than a cosmic impact--a rock.