Stanford Study Ties 252-Million-Year Extinction Survival to Metabolism as 96% of Marine Species Died
Updated
Updated · SciTechDaily · Jul 18
Stanford Study Ties 252-Million-Year Extinction Survival to Metabolism as 96% of Marine Species Died
3 articles · Updated · SciTechDaily · Jul 18
Summary
A Stanford-led study in PNAS found metabolism largely determined which marine animals survived the Permian-Triassic extinction 252 million years ago, helping explain why mollusks endured while brachiopods collapsed.
Experiments on living relatives of ancient groups showed warming and oxygen loss hit slow-metabolism seafloor animals hardest: they tolerated low oxygen in cool water, but their oxygen needs rose sharply as temperatures increased.
The team links that selective die-off to massive volcanism that pumped greenhouse gases into the atmosphere, warming oceans and reducing dissolved oxygen during the “Great Dying,” which killed 96% of marine species and 70% of land animals.
That turnover reshaped ocean life: brachiopods once outnumbered bivalves, but only about 400 brachiopod species remain today versus roughly 10,000-15,000 bivalves.
Researchers said the ancient event is not a direct modern parallel, but the same biological pressures—warmer water holding less oxygen while raising animals’ oxygen demand—are already increasing in parts of today’s ocean.
Earth's worst extinction was a metabolic stress test. Which modern sea creatures are most likely to fail it?
Ancient extinctions warn of ocean collapse from warming. But could modern geology offer an unexpected escape route?
A prehistoric crisis of heat and low oxygen decided life's winners. Is humanity now repeating that lethal experiment?
Survival by Metabolism: Lessons from the Permian–Triassic Extinction for Today’s Climate Crisis
Overview
A new Stanford-led study published in July 2026 reveals that metabolism was the key factor in determining which marine species survived Earth's greatest extinction, the Permian–Triassic event about 252 million years ago. This mass extinction, the most severe in Earth's history, dramatically reshaped marine life. The research shows that species with higher metabolic rates and better ability to handle environmental stressors like rising temperatures and low oxygen were more likely to survive. These findings explain why certain groups, such as bivalves, replaced others like brachiopods, and highlight how ancient metabolic traits still shape today's ocean ecosystems.