In early March 2025, Royal Society Open Science published a fascinating study on a long-standing mystery in paleontology: how temnospondyls, ancient amphibian-like creatures, not only survived but thrived after the most catastrophic extinction event in Earth’s history. The study, The Ecology and Geography of Temnospondyl Recovery After the Permian–Triassic Mass Extinction, was led by Aamir Mehmood, Suresh A. Singh, Armin Elsler, and Michael J. Benton.
How Did Temnospondyls Survive When So Many Others Didn’t?
About 252 million years ago, the Permian-Triassic mass extinction marked the most devastating biological crisis in Earth’s history, wiping out an astonishing 90% of marine species and 70% of land vertebrates. Triggered by massive volcanic eruptions in what is now Siberia, the event unleashed extreme global warming, ocean acidification, and widespread anoxia, making survival nearly impossible for most species. It was the closest life has ever come to complete annihilation. Most groups struggled to recover, but temnospondyls—a clade of semi-aquatic predators resembling massive salamanders—defied the odds.
So how did they do it? This study suggests it wasn’t because of any unique evolutionary breakthroughs. Instead, temnospondyls seemed to bounce back simply because they were already well-suited to surviving harsh conditions. Their fossils show a wide range of skull shapes, sizes, and feeding strategies, meaning they could adapt to different environments. They also lived in freshwater, a habitat that may have been more stable than terrestrial ecosystems during the extinction aftermath.
The ‘Tropical Dead Zone’ Wasn’t So Dead After All
For years, scientists thought the tropics were uninhabitable after the mass extinction—a so-called “Tropical Dead Zone” too hot for life to survive. But this study challenges that idea. Fossil evidence shows that some temnospondyls actually lived in equatorial regions, suggesting there were at least pockets of survivable habitat. It’s possible that freshwater environments provided a buffer against the extreme climate swings of the time.
No Evolutionary Overdrive—Just Business as Usual
When creatures survive a mass extinction, we often assume they must have evolved some kind of “superpower” to adapt. But this research found no signs of rapid evolutionary change in temnospondyls. Their skull shapes and body sizes followed predictable patterns of evolution, similar to what is seen in stable ecosystems.
Some groups, like the Trematosauria, did explore more extreme body shapes, but overall, temnospondyls didn’t dramatically reinvent themselves. Instead, they stuck to the strategies that had already worked for them before the extinction.
The Beginning of the End
Despite their early success, temnospondyls couldn’t hold onto their dominance forever. By the Middle Triassic, their numbers were dwindling, and by the Late Triassic, they were being replaced by reptiles like early crocodile relatives. The study suggests this decline wasn’t due to competition but rather shifting climates and habitat loss.
A few members of the group, the chigutisaurids, clung on into the Jurassic and Cretaceous, but they were limited to southern regions before disappearing entirely.
What We Can Learn From Their Story
The rise and fall of temnospondyls offer valuable lessons about how life recovers from mass extinctions. Traditionally, we’ve assumed that ecosystems rebuild from the bottom up—plants and small creatures recover first, then larger predators appear later. But this study adds to growing evidence that recovery can be unpredictable. Large predators, including temnospondyls, rebounded quickly, possibly because they had generalist diets and flexible lifestyles that helped them exploit whatever resources were available.
Their success also highlights the importance of freshwater habitats, which may have served as crucial refuges when conditions on land became too extreme.
Final Thoughts
Temnospondyls were among nature’s great survivors. Their ability to persist through the worst catastrophe in Earth’s history—and even thrive afterward—tells us something fundamental about the resilience of life. But their eventual decline reminds us that even the toughest survivors can’t outrun the slow march of environmental change forever.
Research Study Source
- Mehmood, A., Singh, S. A., Elsler, A., & Benton, M. J. (2025). The Ecology and Geography of Temnospondyl Recovery After the Permian–Triassic Mass Extinction. Royal Society Open Science. March 5, 2025. [https://doi.org/10.1098/rsos.241200] (Retrieved March 2025).
