Integrating fossils, anatomy, and physics to unravel the interplay between body size and locomotor ecology in the ancient forerunners of amphibians

This project studies temnospondyls, extinct amphibian relatives that lived for over 200 million years and ranged from small animals to giants. Amphibians help keep freshwater ecosystems healthy and serve as early warning signs of environmental stress, yet many species are declining rapidly. To manage the habitats Americans depend on, we need to understand how amphibians became successful and why some body plans endure while others disappear. Because fossils preserve bones but not behavior, computer simulations will be used to test how animals of different sizes likely walked, swam, and moved between water and land. By combining fossils, living amphibians, and computer models, this study will show how body size and limb performance shaped ecology and survival across changing habitats through evolutionary time. This project synthesizes fossils with extant data and biomechanical simulations to unravel the interplay between size, shape, locomotion, and ecology. Key objectives include: 1) quantifying anatomical factors in salamanders, the modern descendants of temnospondyls; 2) producing quantitative assessments of limb performance across extinct taxa; and 3) testing how body size constrained ecological innovation over time. The resulting insights will provide a powerful lens to study how mechanical factors shape macroevolution, helping to explain why certain body plans persist while others fail. This project will also generate a novel framework for interpreting locomotor efficacy during land-water transitions, paving the way for future investigations into major evolutionary shifts in vertebrate history. The project includes outreach programs to improve public literacy in science. Educational activities will be held during National Fossil Day at the Harvard Museum of Natural History, targeting families and schools. These sessions will showcase amphibian biology, including paleontology, behavior, and wildlife conservation. Research outcomes will be disseminated through conference presentations and publications. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. NSF Award ID: 2528867 | Program: 01002627DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Stephanie Pierce | Institution: Harvard University, CAMBRIDGE, MA | Award Amount: $300,000 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2528867 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2528867.html