The role of ecology as a modulator of sexual conflict in the wild: an experimental approach with Drosophila melanogaster

Sexual conflict is essential to understand phenotypic evolution in promiscuous species.

Yet we know very little about how it operates in the wild and how ecology may help explain the overwhelming variation in sexual traits showcased in nature.

I propose an ambitious multi-disciplinary approach combining phenotypic-level measurements with transcriptomic and proteomic tools to study the ecological factors that underlie variation in sexual conflict in Drosophila melanogaster, at a global ecological scale.

This is a powerful system because: a) it has a global distribution that spans marked ecological variation, b) it exhibits intense sexual conflict including well studied pre- and post-copulatory traits, c) its sexual conflict traits have been shown to harm females and decrease population viability, d) it affords the use of state-of-the-art molecular techniques and e) despite being a model organism in sexual selection and sexual conflict studies, we know very little about the role of ecology.

I will study 1) how temperature, population density, sex ratio and habitat characteristics modulate sexual conflict across different levels of sexual selection (i.e. pre-copulatory vs. post-copulatory) and genetic conflict (i.e. intra-locus vs. inter-locus sexual conflict), 2) the role of phenotypic plasticity and local adaptation in shaping sexual conflict responses to temperature, 3) how this may impact population viability, and 4) the physiological and genetic mechanisms underlying variation in sexual conflict.

Given the novelty and reach of the questions addressed this action represents an important advance in our understanding of how sexual conflict evolves and operates in nature, as well as the consequences in terms of potential eco-evolutionary feedback on population viability.

Understanding the latter can be particularly relevant to predict the fate of populations and species facing directional environmental changes, such as those imposed by global warming.