NSF PRFB FY 2023: Behavioral and Physiological Innovations Facilitating the Evolution of Brood Parasitism

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2023, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment, and Phenotypes. The fellowship supports research and training of the fellow that will contribute to the area of Rules of Life in innovative ways. This project will investigate the evolution of selfish begging behavior in birds through muscle physiology and genomics. For many animals, survival is most challenging immediately after hatching/birth and natural selection strongly favors the evolution of extreme (and sometimes bizarre) behavioral traits at this stage to enhance offspring survival. One example of this is begging to receive care in nestling birds. The Fellow will study how begging evolved and characterize how selfish traits promote competition among offspring by applying behavioral, genomic, and physiological techniques to nestling birds raised with chicks they are related to or unrelated to. The Fellow, as a former teacher, will also conduct outreach on the relationship between muscle physiology and behavior at local schools and mentor undergraduate students both at the host institution and from minority-serving institutions. The process by which traits evolve iteratively over time and support the diversification of behavioral phenotypes is of critical importance to generating a mechanistic understanding of behavior. This is particularly interesting in the case of early life traits, which are theorized to be under a stronger selective force than those traits that manifest after first reproduction. Begging in nestling birds is a model system for addressing questions of iterative evolution because it is well-studied from a behavioral perspective. However, little is known about the molecular and physiological mechanisms that facilitate/constrain begging as a behavior or how iterative trait evolution guides the transition from specialized begging directed at parents to a generalized parasitic begging phenotype that may be successful at coercing care in a variety of host species nests. The goal of this research combines an emerging model of layered evolution, where the innovation of behavioral traits can be modeled by looking at molecular shifts in the expression of individual genes and how it builds on ancestral evolutionary scaffold, with physiological methods like in situ muscle recording to explore the basis of mechanistic constraints on begging evolution. The project’s broader impacts target the retention and development of scientists from under-represented backgrounds through middle school outreach and through the training and direct mentorship of undergraduates in the host institution’s NSF REU program. 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.