Characterizing the effects of evolution on nutrient cycling

点击翻译按钮获取中文摘要

The overall goal of my research program is to characterize the ecological consequences of evolutionary processes. In particular, my students and I characterize how animal evolution alters the flows of energy and nutrients in aquatic ecosystems. We work on the three-spined stickleback species complex from coastal British Columbia because it is one of the most important models for studying speciation, an evolutionary process that generates species. Stickleback evolution has led to a tremendous diversity in their defensive bony structures (i.e. armour), which protect them from predators. Because it is highly rich in phosphorus, variability in bone content has been invoked to explain differences in nutrient storage and recycling among fish species. However, hypotheses linking the evolution of bony traits with nutrient recycling have not been tested. Sticklebacks provide us with a unique opportunity to test these hypotheses, thereby gaining a better understanding of how animal traits influence their roles in ecosystem processes. We will characterize how armour traits affect the ability of sticklebacks to store and recycle nitrogen and phosphorus - two elements that limit primary production in aquatic ecosystem. Using a combination of field surveys and experiments, we will assess the effects of armour on stickleback elemental composition (the concentrations and proportions of elements in their bodies), their dietary demands for nitrogen and phosphorus, their capacity to recycle these elements, and the effects of these recycled elements on primary production. We will sample a number of stickleback populations from marine and freshwater environments, which encompass large differences in armour traits. My research will significantly advance our understanding of how evolution affects ecosystems. This understanding is important for a range of evolutionary and ecological processes, and is also required for effective conservation management. This research also addresses key mechanistic questions about nutrient recycling, a regulating ecosystem service which is important for ecosystem stability. Findings from this program will therefore benefit evolutionary biologists, ecosystem scientists, and conservation managers.