Doctoral Dissertation Research: The ecological context of early ape evolution

This doctoral dissertation project examines the early diversification of apes within the broader context of mammalian community evolution. Leveraging rich fossil collections, the investigators characterize mammal assemblages from multiple, well-studied localities to examine how time, space and environmental factors impacted mammalian community structure. The scientific importance of this project lies in providing a comparative backdrop of mammalian evolution to better understand the ecological setting for major adaptations in the ape and human lineage. More broadly, this project can have significant impacts for science and society by expanding participation in science through graduate training and research opportunities for undergraduate students from groups underrepresented in STEM research. A relational database of paleontological data assembled through this project is planned for public distribution to scientists and educators via the Data Repository at the University of Minnesota (DRUM). Other results will be made available through peer-reviewed publications, conference presentations, and public outreach opportunities aimed at providing scientific engagement at public schools and museums.

The early divergence of ape lineages, during which several major adaptive characteristics of the ape-human clade were established, is primarily recorded in the early Miocene (ca. 23-16 Ma). Although fossil apes from this time have been the subject of intense study, little work has been done to properly situate the diversity of these species within the broader context of mammalian community evolution. This project asks the central question: how did environment, time, and geographic distance influence the structure of early Miocene mammalian communities? Using large fossil assemblages, this project pursues four specific questions: 1) do fossil assemblages from major collecting areas represent differences in mammalian community structure? 2) do changes in mammalian community structure track environmental differences inferred from associated paleoecological proxies? 3) are mammalian community structures most similar among assemblages that are closest in age? and 4) does similarity in mammalian community structure decrease with increasing geographic distance between assemblages? These questions are addressed by analyzing the mammalian community structure across 13 fossil localities that are already well-characterized in terms of age and paleoenvironment. By situating mammalian community succession within temporal, geographic, and environmental contexts, this project can inform our understanding of how these factors influenced changes among mammal species, thereby clarifying the ecological parameters within which major adaptations in the ape and human lineage arose.

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.