Abstract: The most exciting scientific questions are those at the crossroads of different disciplines. Genomics has revolutionized the study of biology and has reinforced the significance of Dobzhansky's famous quip, "Nothing in biology makes sense except in the light of evolution." My research combines computational and experimental approaches to investigate: (i) the factors influencing phylogenetic accuracy and their usefulness in obtaining more robust phylogenies, (ii) the molecular origins of multicellularity in fungi and animals, and (iii) the molecular foundations of the fungal lifestyle. In my talk, I will concentrate on describing recent work on the last of the three aims. Fungi exhibit a remarkably diverse array of physiologies and eating habits, suggesting that metabolism is of high ecological and evolutionary significance. We have conducted population genomic, functional and phylogenomic analyses to better understand the evolutionary origins, maintenance and demises of the galactose assimilation pathway across the fungal kingdom. I will discuss the implications of our findings for the maintenance of complex variation in natural populations and for shaping genome architecture.