A new study reveals the remarkable resilience of inconspicuous small and soft animals.

About 252 million years ago, something catastrophic happened on our planet. About 95 percent of all life on earth was brutally wiped off the face of the earth by rigorous climate change. Scientists consider this mass extinction, which took place during the transition from the Permian to the Triassic, as the largest ever. It then took millions of years for species to recover. And now researchers have discovered which creatures were the most resilient and the first to resurface.

South China

Researchers traveled to southern China for the study. And that is not without reason. “The mass extinction at the end of the Permian and the recovery of life in the early Triassic are very well documented throughout southern China,” said study researcher Michael Benton. In some places, huge numbers of beautifully preserved fossils have even been found. “These fossils show us when and where certain animals thrived during the early Triassic,” Benton said.

Reconstruction

The team examined the traces and caverns left behind discovered on the South China seabed. Subsequently, they were able to reconstruct how life in the sea recovered after the catastrophic mass extinction. “We were able to map the recovery of benthos (the organisms that live on or around the seabed, ed.), nekton (the organisms that can actively move in the water column, ed.) and soft, burrowing animals. to bring,” said Benton.

Worms and crayfish

Which animals were the first to recover after the largest mass extinction ever? These were so-called detrivores; animal organisms that feed by eating sediment on the sediment and aquatic plants. “It’s about worms and crustaceans,” says researcher Alison Cribb. “The recovery of filter-feeding organisms (non-mobile animals that mainly feed on plankton and other food floating in the water, ed.) such as armpods, bryozoans and many bivalves took much longer.”

Resilience

The study reveals the remarkable resilience of nondescript soft and small creatures such as worms and crustaceans, which apparently emerged first. “In the beginning, there were only a few survivors,” said study researcher Chunmei Su. “Then animals living in deep waters started to recover first.” The researchers also suspect that detrivores may be the reason why it took a relatively long time for filter-feeding organisms to appear. “Detrivores may have made quite a mess of it on the seafloor,” Cribb said. “The water could have been very polluted with mud, preventing filter-feeding organisms from thriving on the seafloor.” Still, filter-feeding organisms certainly weren’t the last to bounce back. “Some animals, such as corals, had completely disappeared,” said study researcher Zhong-Qiang Chen. “Coral reefs didn’t really come back until much later.”

Important

Why is it important to learn more about the mass extinction that happened 252 million years ago? “The answer is that this crisis at the end of the Permian — and so devastating to life on the planet — was caused by global warming and ocean acidification,” said researcher Xueqian Feng. And that may sound familiar to you; we see similar circumstances today. “Apparently, soft animals were better able to cope with this than skeletal organisms,” Feng said.

As mentioned, during the Permian-Triassic mass extinction, about 95 percent of the species living in the ocean became extinct. And that in less than 100,000 years. While that may seem long, in geological terms, that’s really fast. During this period, virtually all life that had existed over a span of 3,800,000,000 years died out. In proportion, this equates to the extinction of 95 percent of marine life in just 14 minutes of a year! Then it took millions of years for life to recover, with apparently small, soft animals best suited to cope with high CO2 concentrations and global warming.