Male and female diet choice in response to the socio-sexual environment

From recent advances in animal nutrition research, it is now clear that for many species, it is not only the amount of food eaten but also the protein and carbohydrate content of that food that influences life history and health1. In particular, diets that are relatively high in protein and low in carbohydrate enhance reproduction, whereas low protein and high carbohydrate diets prolong life. However, current understanding of the 'ideal' diet is often limited to simplified social environments. In particular, we know little about how nutritional preferences and optima shift in response to mating, or about how individuals can achieve their dietary optima despite conflicts of interest over nutrition with their mates and family members.

The goal of this studentship is to examine how the diets that maximize health, lifespan and reproduction vary with the ecological and social setting. The project will use the fruit fly Drosophila melanogaster because it is an experimentally tractable animal with well-established nutritional and behavioural protocols. Research questions to be addressed include:

How do the diets that maximize male and female lifespan and reproduction change with mating frequency?

To what extent do evolutionary conflicts of interest - for example, when mothers have different optimal diets from their offspring - shape dietary preferences?

By what mechanisms might males influence the nutritional preferences of their mates? A candidate mechanism is male seminal proteins, which are known to influence female behaviour and physiology4.

These questions will be addressed in laboratory experiments that manipulate diet composition and interactions with the opposite sex, followed by assays of reproduction, lifespan, and feeding and mating behaviour. The project will include assays of replicated populations of flies that have undergone experimental evolution in the supervisory team's laboratories under low, moderate or high conflict between males and females; and the use of genetically manipulated flies (e.g., in which candidate seminal proteins are not expressed). There will also be the opportunity for the student to develop the project independently by exploring research questions inspired by results from the initial experiments.

The proposed research is closely related to the primary supervisor's NERC-funded fellowship research. The research targets two areas of NERC remit: Ecology, Biodiversity and Systematics (behavioural ecology; foraging behaviour); and Genetics & Development (adaptation and the evolution of life histories).