Dr. Somero's group studies the effects of environmental factors, such as temperature, salinity, hydrostatic pressure, and oxygen availability on marine animals. Their studies of molecular evolution focus on macromolecular adaptations, for instance, changes in protein structure that underlie adaptive variation in functional properties and stability, and "micromolecular" adaptations that provide the appropriate intracellular milieu for macromolecular function. Studies of short-term responses to environmental change use DNA microarray technology to follow shifts in gene expression in marine organisms.