After years of digging across Africa, scientists have built a clearer picture of life just before Earth’s worst die-off. New fossils reveal bustling ecosystems in southern Pangea, from burrowers to tusked plant-eaters to saber-toothed hunters.
The fossils show which species thrived before the “Great Dying” and hint at why so many vanished. A team led by researchers at the University of Washington and the Field Museum pulled together this record in a 14-paper collection.
A new perspective on mass extinctions
The research spans more than 15 years of field seasons and lab study, and it focuses on the late Permian, which ran from 299 to 252 million years ago.
Christian Sidor is a UW professor of biology and curator of vertebrate paleontology at the UW Burke Museum of Natural History & Culture.
“This mass extinction was nothing short of a cataclysm for life on Earth, and changed the course of evolution,” said Sidor. “But we lack a comprehensive view of which species survived, which didn’t, and why.”
“The fossils we have collected in Tanzania and Zambia will give us a more global perspective on this unprecedented period in our planet’s natural history.”
Fossil hunt across southern Pangea
The study centers on three basins rich in fossils and extinction records in southern Africa: the Ruhuhu Basin in southern Tanzania, the Luangwa Basin in eastern Zambia, and the Mid-Zambezi Basin in southern Zambia.
Most specimens came from month-long expeditions over the past 17 years. Others were museum pieces collected decades ago and newly analyzed.
“These parts of Zambia and Tanzania contain absolutely beautiful fossils from the Permian,” Sidor said. “They are giving us an unprecedented view of life on land leading up to the mass extinction.”
Fieldwork began in 2007. The team, which included students and postdoctoral researchers, made five trips to the Ruhuhu Basin and four to the Mid-Zambezi and Luangwa basins. The work was conducted in partnership with the Tanzanian and Zambian governments.
Crews hiked between distant sites, stayed in villages, and sometimes camped under the stars. One night, they awoke to the ground quaking from a nearby elephant herd. All collected fossils will return to Tanzania and Zambia after study.
Fossils challenging old extinction records
The Permian Period closed the Paleozoic Era. During this time, life that first evolved in the oceans spread onto land and built complex food webs. By the late Permian, amphibian and reptile-like animals roamed environments from early forests to arid valleys.
The end-Permian extinction, whose cause is still debated, shattered many of those ecosystems. It cleared the slate for the Mesozoic, which produced dinosaurs and, later, the first birds, flowering plants, and mammals.
For decades, much of what scientists knew about this transition came from fossil discoveries in South Africa’s Karoo Basin, which preserves a near-continuous record across the extinction boundary.
Since the 1930s, however, researchers have recognized that Tanzania and Zambia also preserve superb sequences from this interval.
The new series builds on earlier work, including a 2018 synthesis of post-Permian life from the Ruhuhu and Luangwa basins, by pushing deeper into the Permian layers.
Final flourishing before collapse
The papers describe several new species of dicynodonts – small, burrowing, herbivorous synapsids with beak-like snouts. Many had a pair of small tusks that likely helped with digging. By the time the crisis hit, dicynodonts dominated plant-eating niches on land.
The team also reports multiple new gorgonopsians – large, saber-toothed predators that stalked the same landscapes. In addition, they identify a new temnospondyl, a hefty, salamander-like amphibian that lived in rivers and swamps.
Together, these animals map the food webs across southern Pangea in the final Permian chapters. They also allow direct comparison with South Africa’s fossil record.
That comparison is crucial for testing which lineages were widespread and which were local, and for tracking who faded and who endured.
“The number of specimens we’ve found in Zambia and Tanzania is so high, and their condition is so exquisite, that we can make species-level comparisons to what paleontologists have found in South Africa,” Sidor explained.
“I know of no better place on Earth for obtaining such detailed information about this time period, or for making such precise conclusions and comparisons.”
Matching fossil timelines worldwide
By putting multiple regions side by side, researchers can test patterns of survival and collapse rather than rely on a single archive. The African basins now offer parallel timelines bracketing the end-Permian horizon.
With that, scientists can probe whether communities unraveled in the same way everywhere, or if stress hit different places differently.
“We can now compare two different geographic regions of Pangea and see what was going on both before and after the end-Permian mass extinction,” Sidor said. “We can really start to ask questions about who survived and who didn’t.”
The answers could reveal how ecosystems respond when pushed to the brink. They may also show which traits help lineages ride out cascading shocks.
That fossil evidence sharpens the narrative of Earth’s greatest extinction and the long recovery that followed. It also deepens our view of the world the dinosaurs inherited and reshaped.
The research is published in the Journal of Vertebrate Paleontology.
—–
Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates.
Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.
—–
Source link
