{"id":32424,"date":"2025-07-02T11:13:11","date_gmt":"2025-07-02T11:13:11","guid":{"rendered":"https:\/\/www.europesays.com\/us\/32424\/"},"modified":"2025-07-02T11:13:11","modified_gmt":"2025-07-02T11:13:11","slug":"the-great-dying-wiped-out-90-of-life-then-came-5-million-years-of-lethal-heat-new-fossils-explain-why","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/us\/32424\/","title":{"rendered":"The \u2018Great Dying\u2019 wiped out 90% of life, then came 5 million years of lethal heat. New fossils explain why"},"content":{"rendered":"

Around 252 million years ago, life on Earth suffered its most catastrophic blow to date: a mass extinction event<\/a> known as the \u201cGreat Dying\u201d that wiped out around 90% of life.<\/p>\n

What followed has long puzzled scientists. The planet became lethally hot and remained so for 5 million years.<\/p>\n

A team of international researchers say they have now figured out why using a vast trove of fossils \u2014 and it all revolves around tropical forests.<\/p>\n

Their findings<\/a>, published Wednesday in the journal Nature Communications, may help solve a mystery, but they also spell out a dire warning for the future as humans continue to heat up the planet by burning fossil fuels.<\/p>\n

The Great Dying was the worst of the five mass extinction events that have punctuated Earth\u2019s history, and it marked the end of the Permian geological period.<\/p>\n

It has been attributed to a period of volcanic activity in a region known as the Siberian Traps, which released huge amounts of carbon and other planet-heating gases into the atmosphere, causing intense global warming. Enormous numbers of marine and land-based plants and animals died, ecosystems collapsed and oceans acidified.<\/p>\n

What has been less clear, however, is why it got so hot and why \u201csuper greenhouse\u201d conditions persisted for so long, even after volcanic activity ceased.<\/p>\n

\u201cThe level of warming is far beyond any other event,\u201d said Zhen Xu, a study author and a research fellow at the School of Earth and Environment at the University of Leeds.<\/p>\n

Some theories revolve around the ocean and the idea that extreme heat wiped out carbon-absorbing plankton, or changed the ocean\u2019s chemical composition to make it less effective at storing carbon.<\/p>\n

But scientists from the University of Leeds in England and the China University of Geosciences thought the answer may lie in a climate tipping point: the collapse of tropical forests.<\/p>\n

The Great Dying extinction event is unique \u201cbecause it\u2019s the only one in which the plants all die off,\u201d said Benjamin Mills, a study author and a professor of Earth system evolution at the University of Leeds.<\/p>\n

To test the theory, they used an archive of fossil data in China that has been put together over decades by three generations of Chinese geologists.<\/p>\n

\"A<\/p>\n

A complicated broad leaf seed fern from a pre-extinction South China rainforest. – Dr. Zhen Xu<\/p>\n

\"A<\/p>\n

A post-extinction plant called a lycopod sporophyll. – Dr. Zhen Xu<\/p>\n

They analyzed the fossils and rock formations to get clues about climate conditions in the past, allowing them to reconstruct maps of plants and trees living on each part of the planet before, during and after the extinction event. \u201cNobody\u2019s ever made maps like these before,\u201d Mills told CNN.<\/p>\n

The results confirmed their hypothesis, showing that the loss of vegetation during the mass extinction event significantly reduced the planet\u2019s ability to store carbon, meaning very high levels remained in the atmosphere.<\/p>\n

Forests are a vital climate buffer as they suck up and store planet-heating carbon. They also play a crucial role in \u201csilicate weathering,\u201d a chemical process involving rocks and rainwater \u2014 a key way of removing carbon from the atmosphere. Tree and plant roots help this process by breaking up rock and allowing fresh water and air to reach it.<\/p>\n

Once the forests die, \u201cyou\u2019re changing the carbon cycle,\u201d Mills said, referring to the way carbon moves around the Earth, between the atmosphere, land, oceans and living organisms.<\/p>\n

Michael Benton, a professor of paleontology at the University of Bristol, who was not involved in the study, said the research shows \u201cthe absence of forests really impacts the regular oxygen-carbon cycles and suppresses carbon burial and so high levels of CO2 remain in the atmosphere over prolonged periods,\u201d he told CNN.<\/p>\n

\"Another<\/p>\n

Another post-extinction lycopod. – Dr. Zhen Xu<\/p>\n

It highlights \u201ca threshold effect,\u201d he added, where the loss of forests becomes \u201cirreversible on ecological time scales.\u201d Global politics currently revolve around the idea that if carbon dioxide levels can be controlled, damage can be reversed. \u201cBut at the threshold, it then becomes hard for life to recover,\u201d Benton said.<\/p>\n

This is a key takeaway from the study, Mills said. It shows what might happen if rapid global warming causes the planet\u2019s rainforests to collapse in the future \u2014 a tipping point<\/a> scientists are very concerned about.<\/p>\n

Even if humans stop pumping out planet-heating pollution altogether, the Earth may not cool. In fact, warming could accelerate, he said.<\/p>\n

There is a sliver of hope: The rainforests that currently carpet the tropics may be more resilient to high temperatures than those that existed before the Great Dying. This is the question the scientists are tackling next.<\/p>\n

This study is still a warning, Mills said. \u201cThere is a tipping point there. If you warm tropical forests too much, then we have a very good record of what happens. And it\u2019s extremely bad.\u201d<\/p>\n

For more CNN news and newsletters create an account at CNN.com<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"Around 252 million years ago, life on Earth suffered its most catastrophic blow to date: a mass extinction…\n","protected":false},"author":3,"featured_media":32425,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8],"tags":[27236,27239,27238,27232,9189,159,27233,67,132,27235,68,27237,27234],"class_list":{"0":"post-32424","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-benjamin-mills","9":"tag-china-university-of-geosciences","10":"tag-climate-conditions","11":"tag-mass-extinction-event","12":"tag-nature-communications","13":"tag-science","14":"tag-tropical-forests","15":"tag-united-states","16":"tag-unitedstates","17":"tag-university-of-leeds","18":"tag-us","19":"tag-volcanic-activity","20":"tag-zhen-xu"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@us\/114783348687170837","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/32424","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/comments?post=32424"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/32424\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media\/32425"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media?parent=32424"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/categories?post=32424"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/tags?post=32424"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}