Stanford study links mass extinction to metabolic inability to survive w…

A Stanford-led study has provided the most detailed explanation yet for the Permian-Triassic mass extinction, the most severe in Earth’s history, which wiped out 96% of marine species and 70% of land animals around 252 million years ago. The research, published in the *Proceedings of the National Academy of Sciences*, links the catastrophe to a combination of volcanic activity, ocean warming, and oxygen depletion, with a critical role played by the metabolic limitations of ancient marine life.

The study, led by Erik Anders Sperling of Stanford’s Doerr School of Sustainability, focused on why certain species survived while others perished. It found that organisms with slower metabolisms, such as brachiopods and sea lilies, were disproportionately affected. These creatures, which dominated seafloors for 280 million years, struggled to cope with the warming, oxygen-poor waters triggered by a surge of carbon dioxide and methane from Siberian volcanic eruptions. In contrast, species with faster metabolisms, like mollusks and echinoderms, adapted better, shaping the modern ocean ecosystem.

“The key was how different metabolic rates interacted with environmental stressors,” Sperling said. “The Paleozoic fauna couldn’t keep up with the rapid temperature changes, while modern groups had the physiological tools to survive.” The research involved experiments on living analogs of ancient species, revealing that slow-metabolizing organisms required less oxygen under normal conditions but failed to adapt when temperatures rose, increasing their oxygen demands exponentially.

While volcanic activity was a primary driver, other studies highlighted additional factors. A 2024 paper from the University of Leeds and China University of Geosciences suggested that prolonged El Niño-like events exacerbated the crisis. These mega-El Niños, lasting decades, caused extreme weather variability, including prolonged droughts and floods, which disrupted ecosystems on land and in the oceans. “It wasn’t just warming — it was the wild swings in climate that made survival impossible,” said Paul Wignall, a co-author of the study.

Regional differences in the extinction’s timing also emerged. A UC Davis study analyzing a drill core from Southwest China found that terrestrial ecosystems collapsed in stages, with tropical rainforests dying centuries after high-latitude regions. This challenges the notion of a single, global “hammer blow” and suggests a complex, cascading series of environmental failures. “The land and ocean systems were interconnected but responded at different paces,” said Jianbo Chen, a former UC Davis researcher.

The collapse of tropical forests further worsened the crisis. A 2025 study in *Nature Communications* linked the extinction to the dieback of these ecosystems, which reduced carbon sequestration and prolonged warming. “Forests acted as a carbon sink, but their loss created a feedback loop that kept the planet hot for millions of years,” said Dr. Zhen Xu of the University of Leeds. This mechanism, the researchers argued, explains why the warming after the Permian-Triassic extinction lasted far longer than other volcanic events in Earth’s history.

The Stanford team emphasized parallels to today’s climate crisis. “We’re seeing the same drivers — oxygen loss, warming, and acidification, but at an accelerated pace,” Sperling warned. Current projections suggest global temperatures could rise 1.5–4°C by 2100, mirroring the 8–12°C increase that triggered the Great Dying over thousands of years. However, the study noted that modern societies have the tools to mitigate these risks, unlike the ancient world.

Other research underscored the role of ocean acidification, though it was deemed less critical than warming and oxygen depletion. “Acidification was a contributing factor, but the primary killers were the extreme temperatures and low oxygen levels,” Sperling said. The study also highlighted the importance of preserving modern marine biodiversity, as species with resilient metabolisms may hold clues to surviving future environmental shifts.

The findings collectively paint a picture of an extinction driven not by a single event but by a web of interacting stressors. While the Permian-Triassic crisis reshaped life on Earth, leaving dinosaurs and mammals to dominate, the lessons from the past offer a stark warning. “We’re at a crossroads,” Sperling said. “The choices we make now will determine whether we repeat the mistakes of the past or forge a more sustainable future.”