EMBRACE-EAR-Seed: Establishment of terrestrial herbivory during the Permian of central Pangea

The trophic pyramid, where many plants are consumed by a large number of herbivores, which are, in turn, eaten by a smaller number of carnivores, is the foundation for land-based ecosystems today. In fact, it is one of the earliest features of ecology that students learn in school. This structure, despite its ubiquity, has not always been in place. Three hundred million years ago, during the Permian Period, carnivores were the dominant dietary ecology and herbivores were exceptionally rare. At some point, likely during the Permian, a key shift occurred from the carnivore-dominated ecosystem to the herbivore-dominated environments observed today. The fossil record of Oklahoma, which includes the most diverse and best-preserved fossil vertebrate assemblage from the Paleozoic, offers an exceptional opportunity to explore this change. The goals of this project are to track the evolution of herbivory in different tetrapod clades and assess the patterns and processes that lead to it becoming the foundational dietary ecology of terrestrial environments today. This project will directly support Oklahoma graduate and undergraduate students through scientific and technical skills training, as well as broader institutions by utilizing understudied resources, such as the vertebrate faunal collections at the University of Central Oklahoma and the Sam Noble Museum, Oklahoma’s Museum of Natural History.

The establishment of the modern terrestrial ecosystem structure represents a profound ecological transition in vertebrate history. To evaluate the tempo and mode of this change, this research will 3D scan the teeth from Permian fossil vertebrates recovered primarily from Oklahoma. Subsequently, this work will use the 3D scans to quantify dental complexity, which directly relates to diet in living mammals and saurians, using the Orientation Patch Count Rotated method. The quantification of tooth shape permits direct comparison of dissimilar shapes from a wide variety of vertebrates and will elucidate the strategies that different clades took to consume plants. Changes in dental shape, complexity, and disparity will be evaluated through deep time to elucidate the ecological changes that occurred through the Permian Period. This research seeks to identify when herbivory became the critical diet of terrestrial systems, how different groups varied in their approach to consuming plants, and what strategies were most successful. Ultimately, this work will uncover the patterns that gave rise to modern terrestrial ecosystems.

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.

Award Number: 2432203
Principal Investigator: Keegan Melstrom
Funds Obligated: $196,485
State: OK