Mosquitoes are the deadliest animals on Earth, but out of thousands of species, just a few are responsible for the vast majority of human disease – those species that have recently adapted to specialize in biting and living around humans. We use a combination of population genomics and field ecology, supplemented with behavioral, physiological, and developmental work in a controlled laboratory environment to study how mosquitoes have come to thrive in the human niche, and how this shapes the spread of human disease. Our work spans multiple timescales, ranging from evolutionary responses of mosquitoes to the development of human societies over millennia, to rapid adaptation to growing urban environments in the present day, up to ecological and evolutionary shifts taking place across months. Similarly, we work across multiple spatial scales, ranging from global invasions to the ecology of microhabitats.