Collaborative Research: A Chronology and Ecological Context of Primate and Mammalian Evolution

Arizona State University, Scottsdale AZ

Investigators

Abstract

Primate fossils discovered over the past few hundred years have vastly improved the understanding of primate evolution. However, major questions remain regarding the relationship between local geology and the precise identification of many fossil species. Recently, new fossil primates, including a new ape species, were discovered in Middle Miocene deposits, demonstrating the potential for significant additional finds. In this project, the investigators will reanalyze local geology, search for additional fossils, and reassess previously identified mammal species to develop more precise geological age estimates and advance knowledge about primate and mammalian evolution and environments. The project involves students from underrepresented groups from high school through graduate school, providing them with STEM research opportunities in evolutionary biology, geology, paleontology, and imaging. Furthermore, it will foster research collaborations and training opportunities. Outreach will be provided through various media formats and digitized fossils will be made available to researchers and educators to promote scientific inquiry as part of a virtual laboratory. This project combines paleontological and geological fieldwork with lab-based recovery efforts and isotopic analyses focused on Middle Miocene deposits. The investigators will: (1) recover additional fossils from newly discovered fossil localities; (2) establish a more accurate biochronological and stratigraphic assessment of these localities; and (3) reconstruct the paleoenvironment at these fossil localities to assess how the fauna and paleoecology of the region relate to other well-studied localities. Fossils will be collected through surface surveys and wet sieving of sediments for micromammals in a laboratory setting. A joint faunal identification effort with local faunal experts will allow for a revised, standardized taxonomy and an updated biochronological correlation directly with regional fauna for the first time. Geological survey efforts will concentrate on reinterpretation of the major sandstone stratigraphy with an effort to place the fossil-bearing localities in a firmer relative stratigraphic framework using novel methods in GIS. Paleoenvironmental reconstructions will be conducted via relative faunal abundances and stable isotope analyses on fossil mammal enamel. Finally, regional fossil collections will be digitized using 3D surface scanning and micro-CT imaging, and then made available online to facilitate faunal identifications across researchers and for future scientific study. This project is jointly supported by the Biological Anthropology and Sedimentary Geology & Paleobiology programs. 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.