Evolutionary conflict over animal nutrition and diet choice

点击翻译按钮获取中文摘要

Recent advances in animal nutrition research have produced remarkable findings. Across many species, it is not only the amount of food eaten but also the protein and carbohydrate content of that food that influences health. In particular, diets that are relatively high in protein and low in carbohydrate diets enhance reproduction, whereas low protein and high carbohydrate diets prolong life. These results often lead to a picture of an ideal diet composition that maximizes a species' reproduction and another diet composition that maximizes lifespan, a result of keen interest for human health. However, our current understanding of the ideal diet is limited to overly simplified laboratory conditions. This is a problem because the diet compositions that maximize reproduction and lifespan in benign and stable conditions might not translate to the complex environments that all organisms, including humans, experience in the real world. In particular, an animal's mating frequency might strongly affect its nutritional needs, because increased mating frequency is associated with increased reproduction and lifespan in many species. We currently 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 my research is to address this gap by bringing an evolutionary perspective to nutritional ecology. I aim to discover how the diets that maximize health, lifespan and reproduction vary with the ecological and social settings that animals experience. I will use the fruit fly Drosophila melanogaster, an experimentally tractable animal that shares most of its nutritional physiology with vertebrates - including humans - to enable me to directly test nutritional hypotheses in experiments that are not feasible with human subjects. With this research I will focus on three questions: how diets that maximize lifespan and reproduction change with mating frequency; to what extent evolutionary conflicts of interest - for example, when mothers have different optimal diets from their offspring - shapes dietary preferences; and by what mechanisms might males influence the nutritional preferences of their mates. This work has the potential to contribute to our basic understanding of animal adaptation and to the potential for improving the health, lifespan or reproductive capacity of humans and other animals.