EPSCoR Research Fellows: NSF: The microbiota as a facilitator of adaptation to environmental change

This Research Infrastructure Improvement EPSCoR Research Fellows project will provide a fellowship to a faculty member and training for a graduate student at Oklahoma State University. This work will be conducted with collaborators at the University of Pittsburgh. Climate change is now a major selective pressure for many organisms with consequences for range distributions, timing of migration and breeding, and changes to body shapes and sizes.

However, the mechanisms underlying these changes are often poorly understood and may be critical to predicting the ability of organisms to respond to climate change. The microbiome is a strong candidate mechanism for generating differences in body size, and the avian microbiome is particularly understudied, especially in connection with host phenotypes.

Through the fellowship, the PI aims to use a house sparrow study system to test the idea that gut microbiome composition contributes to body size variation and the ability of organisms to adapt to local environmental change. This project will integrate multiple data types to provide insight into a novel mechanism, microbially mediated plasticity that may allow organisms to respond rapidly to human-induced environmental change.

The broader impact of this project includes undergraduate trainees in the research, the advancement of women in science, and the leveraging of information from fellowship activities to revamp a Physiology course.

Rapid environmental changes challenge the ability of organisms to adapt through genetic mechanisms. To facilitate more rapid responses to environmental change, organisms utilize phenotypic plasticity. Additional plasticity may be conferred by the genes of the diverse microbes inhabiting hosts.

This extended range of phenotypes is called microbially mediated plasticity, and the potential for the microbiome to contribute to host adaptation to environmental change is a novel and largely unexplored mechanism that might enhance host acclimation. Body size is one trait likely to be important in adaptation to environmental change. In endotherms, body size increases with latitude following the ecographic pattern, called Bergmann’s Rule.

Larger body sizes are favored in colder environments for heat retention or greater fat stores. However, despite widespread taxonomic support for Bergmann’s Rule, the mechanisms responsible for generating this pattern are unknown. Through this fellowship, the PI will work with collaborators at the University of Pittsburgh to use house sparrows to test the idea that gut microbiome composition contributes to body size variation and the ability of organisms to adapt to local environmental change.

Specifically, this fellowship will enable the PI to utilize previously collected samples from a widely distributed songbird and: (1) determine the effect of the gut microbiota on adult host phenotypes across environmental gradients, (2) determine the relationships between the gut microbiota and growth rates during development, and (3) determine the effect of host environment on the gut microbiota of developing young through a reciprocal transplant experiment. The fellowship training will also support a new active learning lab for a large undergraduate Physiology course.

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.