Skeleton of an early dinosaur Coelophysis bauri from the Late Triassic. The prolonged restructuring of terrestrial ecosystems in the Early Jurassic coincided with the diversification of dinosaurs. Credit: Courtesy of the Natural History Museum of Los Angeles County
Research team from University of Southern California Dornsife made important discoveries regarding the radical changes caused by increasing greenhouse gases and rising temperatures, which led to mass extinctions, paving the way for the emergence of living organisms. Jurassic Dinosaurs.
Stunning new insights into the catastrophic impact of one of the most devastating events in Earth's history have been revealed by a team led by researchers from the USC Dornsife College of Letters, Arts and Sciences. Their findings not only deepen our understanding of the endingTriassic mass extinction but also offers important lessons for addressing current environmental challenges.
About 200 million years ago, Earth experienced its fourth major mass extinction event. This event, caused by a significant rise in greenhouse gases due to volcanic activity, led to rapid global warming and a major shift in the planet's biosphere, ending the Triassic and launching the Jurassic. Many scientists now believe that Earth is in the midst of another mass extinction, driven largely by similar climate changes.
Earth scientists at USC Dornsife have taken a unique approach to analyzing the impact of this extinction event on both ocean and land ecosystems, using a new “ecological space framework” method that classifies animals only outside their boundaries. Classify. It explains ecological roles and behaviors – from predators that fly or swim to grazing herbivores and from the ocean floor Invertebrates For animals that live in the soil on Earth.
Reconstruction of the Late Triassic ecosystem from Ghost Ranch, New Mexico. Published specimens and species preserved at Ghost Ranch have been integrated into the research team's global ecological dataset. Credit: Victor O. Leschick / Natural History Museum of Los Angeles County
“We wanted to understand not just who survived and who didn't, but how the roles that different species played in the ecosystem changed,” said David Bottger, USC Dornsife professor of earth sciences, biological sciences and environmental studies. author. “This approach helps us see the broader, interconnected environmental picture.”
The study — a collaboration between students and faculty at USC Dornsife and the Natural History Museum of Los Angeles County — was recently published in the journal Proceedings of the Royal Society B.
Marine life suffered, but not as much as land animals
The research revealed a stark difference in the impact on marine and terrestrial ecosystems. While both areas suffered significantly, the results suggest that terrestrial ecosystems were more severely affected and experienced longer-term instability.
In the oceans, approximately 71% of species classes, called genera, have disappeared. Surprisingly, despite this huge loss, the overall structure of marine ecosystems has shown resilience. Predators such as sharks, molluscs known as ammonites, and filter feeders such as sponges and brachiopods, although severely affected, eventually rebounded.
A graphical representation of the concept of the study and its results. Credit: C. Henrik Woolley / Natural History Museum of Los Angeles County
On the ground, the scenario proved bleaker. A staggering 96% of terrestrial species have become extinct, dramatically reshaping the landscape of life on Earth. Large herbivores such as early dinosaurs and many small predators suffered greatly, with significant changes in their numbers and roles within the ecosystem.
“This contrast between land and sea tells us about the different ways ecosystems respond to catastrophic events,” said co-author Alison Cribb, who received her Ph.D. Dornsife received his PhD in geosciences from USC this year and is now at the University of Southampton in the UK. “It also raises important questions about the interplay between biodiversity and ecological resilience.”
Climate change evidence from ancient disaster
The study's findings arouse more than just historical interest; they hold significant implications for today's environmental challenges. “Understanding past mass extinctions helps us predict and perhaps mitigate the effects of current and future environmental crises,” said co-lead author Kirsten Formoso, who is completing her doctoral studies in vertebrate paleobiology at USC Dornsife and will soon move to a position at USC. Rutgers University.
The similarities between rapid global warming at the end of the Triassic and climate change today are particularly striking. “We are now seeing similar patterns – rapid climate change, loss of biodiversity. Learning how ecosystems responded in the past can inform our conservation efforts today,” Böttger said.
He added that the research also provides a rare window into the world as it was more than 200 million years ago. “It's like a time machine, giving us a glimpse into life during a period of profound change.”
The study's eco-space framework, with its focus on functional roles, offers a new perspective on ancient life, according to Frank Corsetti, professor of geosciences and chair of the USC Dornsife Department of Geosciences. “It's not just about identifying fossils,” he said. “It's about piecing together the puzzle of ancient ecosystems and how they work.”
Future projects will delve into the lessons of the past
As they plan further research, the scientists aim to explore how different species and ecosystems recover after extinction, and how these ancient events might parallel current biodiversity loss due to climate change.
Future studies are also planned to examine changes in ecospace dynamics across other periods of deep environmental change in the Archean era.
“We've only just scratched the surface,” Cribb said. “There is a lot to learn about how life on Earth responds to extreme changes, and this new eco-space framework offers great potential to help us do that.”
The pandemic sparks a unique collaborative project
The study was designed, and much of the work was done, over a period of time Covid-19 During the pandemic, Boettger said, restrictions were imposed on many other types of research. “This has produced unique conditions that have fostered and led to the development and completion of this research involving individuals with expertise in a wide range of ancient biological fields, from microbes to invertebrates to… Vertebrates“In marine and terrestrial environments, where everyone is working together to achieve one goal,” he said.
Reference: “Contrasting terrestrial and marine ecospace dynamics after the end-Triassic mass extinction event” by Alison T. Cribb and Kirsten K. Formoso, and C. Henrik Woolley, James Beach, Shannon Brophy, Paul Byrne, and Victoria C. Cassady, and Amanda L. Godbold, Ekaterina Larena, Philip Peter Maxiner, Yun-Hsien Wu, Frank A. Corsetti and David J. Potger, December 6, 2023, Proceedings of the Royal Society B.
doi: 10.1098/rspb.2023.2232
Böttger said that Cribb and Formoso initially conceived the collaboration with his supervision, Corsetti's supervision, and key contributions from the study's other co-authors.
Study investigators include Cribb, Formoso, Böttger, Corsetti, James Beach, Shannon Brophy, Victoria Cassady, Amanda Godbold, Philip Peter Maxiner, and Ekaterina Larena (now at the University of Texas at Austin) of the USC Dornsife Department of Geosciences. In addition to C. Henrik “Hank” Woolley, Paul Byrne, and Yuen-Hsien Wu of USC Dornsife Geosciences and the Natural History Museum of Los Angeles County.
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