We are exposed to fungi every time we breathe/yet the vast majority of these interactions are not harmful. Why do a small subset of fungi cause severe disease in humans? These infections are not passed person-to-person/so whatever provides the selective pressure for some fungi to cause disease must come from the fungal environmental niche. In this project/we will explore the activation of diverse stress pathways in the budding yeast Saccharomyces cerevisiae. We will test whether certain conditions can promiscuously activate multiple pathways and whether promiscuous activation facilitates the ability of fungi to infect other organisms. We will also test how stress pathways respond to extreme weather and whether heat waves/drought/etc./and whether adaptations to those events also increase fungal ability to colonize or infect animals.