Organisms are routinely faced with many abiotic and biotic pressures that impact their survivorship, growth, and reproductive success. For example, a lizard’s ability to perform fitness-based tasks (like foraging or predator evasion) is limited by the thermal dependence of its performance, its hydric and metabolic economy, and its morphological dimensions. Yet, organisms are not exclusively at the whim and mercy of their surroundings. Of key importance is the preeminent role that organisms exert on their own selective environments and, correspondingly, on their evolution. This course considers the diverse ways in which organisms engineer their own evolutionary trajectories. Some of the topics we cover include niche construction, extended phenotypes, behavioral drive, the Bogert effect, and adaptive virulence (particularly in the context of the COVID-19 pandemic).