CAREER: Unlocking the small-mammal fossil record to investigate eco-evolutionary responses to landscape and climate dynamics: a multi-proxy and cross-scale approach

About This Grant

Understanding plant and animal responses to environmental change across space and time remains a longstanding question in biology, with pressing relevance in today’s rapidly changing world. The fossil record provides key information about the influence of climate and landscape on species ecology and evolutionary history; however, parts of the fossil record remain vastly understudied. Small mammals, such as rodents, are challenging to study in the fossil record, yet as a diverse group of early responders to shifts in environmental conditions hold untapped potential for understanding these relationships today and in the past. This research will generate and assess multiple lines of evidence to illuminate long-term responses to environmental change in small mammals across two systems, the Basin and Range Province of western North America and the East Africa Rift in Kenya, over the last 23 million years. Work in the US and Kenya will additionally foster collaboration between student researchers and promote capacity building for national and international researchers in paleontology. Research and educational aims will be unified through a training program that includes workshops and activities centered on 1) advanced approaches in analytical paleobiology, 2) feasible solutions for data sharing, and 3) scientific communication. In collaboration with the Turkana Basin Institute, educational objectives also include a redesigned field course with embedded research in Vertebrate Paleontology and the development of educational materials for local schools in Turkana Basin, Kenya. This CAREER proposal aims to develop novel multi-proxy trait data from the small-mammal fossil record to capture dietary ecology, habitat use, and ecological structure across a hierarchy of taxonomic, spatial, and temporal scales. Research will unfold across the fossil record of two continental systems–the Basin and Range Province of western North America and the East Africa Rift in Kenya–providing a comparative framework for evaluating the roles of global and regional climate change, the expansion of C4 grasslands, and tectonic regime on the eco-evolutionary history of small mammals during the Miocene (23-5 Ma), a period known for the assembly of modern biota. To reconstruct the paleoecology of small mammals (rodents and lagomorphs), this research will develop a multi-proxy toolkit that includes dental metrics, dental topographic analysis from high-resolution microCT scans, and stable isotopic composition using laser ablation methods for sampling sub-millimeter teeth. Trait-based measurements of ecological structure across spatial scales will be evaluated against local-scale paleoenvironmental data and regional-scale tectonic and climate models to test process-level explanations for the observed patterns in the fossil record. Educational objectives include the development of field-, collections-, and lab-based educational and research experiences for students and early-career scientists. The project will additionally foster and support a cohort of US and Kenyan scholars to produce collaborative research, implement feasible solutions to challenges in data sharing, participate in technical training, and generate educational resources for local communities in Kenya. 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.