Postdoctoral Fellowship: PRFB: Proximate origins and ecological and evolutionary consequences of resource polyphenism

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2025. The fellowship supports research and training of the fellow that will contribute to biology in innovative ways. The research will investigate phenotypic plasticity, the phenomenon in which changes in how organisms look, function, and behave are environmentally dependent.

Phenotypic plasticity allows organisms to deal with a variable environment, such as changes in temperature across a day, seasonal rainfall changes, and fluctuating predator densities. The fellow will investigate how plastic responses originate and whether plastic responses expressed early in life impact individuals later in life. Results from the research will allow us to better predict whether and how organisms can respond to rapid environmental change.

Through mentoring undergraduates, participation in high school enrichment programs, and public outreach via blog posts and collaborations with natural history museums, the fellow will support the next generation of researchers and increase public engagement with science.

To investigate the origins and consequences of plastic responses, the fellow will study the Mexican spadefoot toad, Spea multiplicata. This species occurs in the harsh and variable conditions of Southwestern North American deserts. To deal with these complex conditions, these tadpoles have evolved a novel form of plasticity.

Typically, tadpoles develop as a small-headed omnivore form, eating dead plant and animal matter. However, under certain conditions, tadpoles can quickly change their features and express a distinctive large-headed carnivore form. Experimental manipulation of the environment will allow for testing the independent and interactive effects of specific environmental conditions that may influence the transition from omnivore to carnivore.

Additionally, the fellow will investigate whether this form of plasticity arose via novel gene expression or by co-option of ancestral mechanisms. To assess the long-term consequences of this plasticity, tadpoles of known morph will be raised to adulthood. The relationship between the form an individual expressed as a tadpole and reproductive fitness will then be assessed.

The fellow will learn techniques in transcriptomic and bioacoustic analyses and further develop the conceptual foundation for future research. The fellow will continue growing as an educator by mentoring undergraduate students and conducting outreach programs with high school students and a natural history museum.

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.