Parasitism is a highly successful lifestyle that has evolved repeatedly and independently across the tree of life. My research focuses on understanding how parasites evolve by utilizing eukaryotic biodiversity to identify genomic and evolutionary trends that underpin this widespread lifestyle. Despite the impact of eukaryotic parasites on human health and livelihood, how parasites evolve, specifically the cellular mechanisms that drive the transition from a free-living to parasitic lifestyle, remains unclear, limiting our ability to understand parasite biology and disease. During my EMBO Postdoctoral Fellowship, I will examine the pseudofungi, an important group of pathogens that includes Phytophthora, the cause of potato blight, and in which parasitism has evolved multiple times in parallel. I will use comparative and functional genomics, to reconstruct the evolution of gene families in the pseudofungi, and test the hypothesis that certain groups of organisms may be genetically predisposed to being parasites.