J.I. (Joana) Sabino Pinto, PhD

My current project explores the role of sexual selection in the evolution of disease resistance.

Sexual selection (SS) is a strong evolutionary force that can promote or inhibit adaptation to environmental challenges. When populations face novel pathogens, SS can influence their persistence by impacting the spread of resistance alleles. The Major Histocompatibility Complex (MHC) encodes proteins that recognize pathogens and activate the acquired immune system. Many vertebrates preferentially mate with partners carrying beneficial MHC alleles, conferring higher resistance to the offspring.

​Here, I study the role of SS in the evolutionary dynamics of amphibian resistance to chytridiomycosis (chytrid), an emerging infectious disease that is causing population declines and extinctions worldwide. I will use poison frogs, a species-rich group in which the strength of SS differs between species, and that is experiencing dramatic population declines. I test whether mate choice is influenced by i) MHC and ii) infection status of both partners. Subsequently, I will use comparative analysis and field surveys to iii) evaluate the association between the strength of SS and species’ susceptibility to chytrid, testing the prediction that species with strong SS are more resistant.

​This project not only contributes to our general understanding of the role of SS in adaptation and disease dynamics, but also present the first experimental analysis of MHC-based mate choice in amphibians. Results are highly relevant for amphibian conservation, by identifying a major factor underlying species differences in chytrid resistance, which will help to set conservation priorities.