A Multiproxy Exploration of the Terminal Ediacaran Stage at the Nevada National Security Site

Roughly 550 million years ago, life on Earth underwent a major transformation. During this time at the end of the Ediacaran Period the first animals began to form hard shells, move across the sea floor, and interact in new ways, including hunting and burrowing. These innovations laid the foundation for the “Cambrian Explosion,” a burst of evolutionary change that produced nearly all major animal groups. However, the fossil record from this critical time remains incomplete, and major questions persist about how and why these changes occurred. This project investigates ancient rocks at the Nevada National Security Site (NNSS), a region that has been closed to paleontological study for over 70 years. By uncovering and analyzing fossils preserved in these rocks, this research will provide new insights into the earliest animals and how they shaped Earth’s ecosystems. In addition to advancing scientific discovery, the project supports student training, public science outreach, and national collaboration, helping connect society with its deep evolutionary past. This project will be the first to systematically investigate Ediacaran- to Cambrian-aged strata within the Nevada National Security Site (NNSS), with the goal of understanding biotic and environmental dynamics during the terminal Ediacaran Period. The study focuses on fossiliferous carbonate and siliciclastic units that may preserve cloudinomorph-grade taxa and associated trace fossil assemblages, with particular attention to characterizing evidence of early biomineralization, ecological interactions (e.g., predation), and taphonomic pathways. The research team will employ high-resolution imaging (including scanning electron microscopy and X-ray tomographic microscopy), geochemical analyses (e.g., elemental mapping, stable isotope chemostratigraphy), and stratigraphic correlation to document fossil morphology, reconstruct paleoecological settings, and assess facies changes and preservational controls. The project also aims to provide data relevant to defining the proposed Terminal Ediacaran Stage of the geologic time scale and will contribute to international stratigraphic efforts through collaboration with the Ediacaran Subcommission of the International Commission on Stratigraphy. Outcomes will include taxonomic revisions, refined geochronologic and paleoenvironmental interpretations, and increased understanding of early animal evolution. 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.