China finds 91 new species of animals that survived ancient mass extinctions

The unique fossils were found in a small quarry in southern China's Hunan province. The results of the study are published in the journal Nature.

Between 2021 and 2024, the Chinese research team collected more than 50,000 fossil specimens in an area measuring just 12 metres high, 30 metres long and eight metres wide. More than 150 different species were identified in this limited space, of which 91 were new to science.

According to the lead author of the study, Han Zeng of the Chinese Academy of Sciences, the find was "exceptional". Many of the fossils retained soft tissue - gills, intestines, eyes and even elements of the nervous system, which is rare for such ancient organisms.

Among the discovered animals are ancient relatives of worms, sponges and jellyfish, as well as numerous arthropods, including radiodonts - large predators with spiny limbs and eyes on stalks, which were at the top of the food chain of the Cambrian period.

What makes the find particularly valuable is its age. The fossils date back to about 512 million years ago and belong to the period immediately after the so-called Sinking extinction, which occurred about 513 million years ago. At that time, scientists estimate that up to half of all marine animals disappeared - probably due to a dramatic drop in oxygen levels in the ocean.

The new fossil fauna, called Huaiyuan biota, is the first major discovery of soft-bodied organisms that lived in the immediate aftermath of the disaster. According to Han Zeng, it "opens a new window into understanding how life recovered from the extinction event."

Independent researchers say the finding also helps us understand which ecosystems were hardest hit. According to evolutionary biologist Michael Lee of the South Australian Museum, the Sino extinction particularly affected shallow-water life forms, while inhabitants of deeper waters were protected - similar to the way a home's basement is better insulated from outside temperature fluctuations.

Scientists were also surprised to learn that some species from the Chinese quarry had previously been found in the famous Burgess Shale sediments in Canada. This indicates that already in the early stages of Cambrian evolution, animals were able to spread over vast distances.

Although the Sinsky extinction is not among the "big five" of the most famous mass extinctions, researchers emphasise that over the past 540 million years on Earth could have occurred at least 18 such catastrophes. Against this backdrop, scientists are increasingly warning that the planet today may be experiencing another mass extinction - already caused by human activity.