Animals use their sensory systems to detect information about the external environment in order to find mates, locate food and habitat and avoid predators. Yet, there is little understanding of the relative amounts of genetic and/or environmental variation in sensory system properties. In this paper, we demonstrate genetic and environmental variation in opsin expression in a population of bluefin killifish. We measured expression of five opsins (which correlates with relative frequency of corresponding cones) using quantitative, real-time polymerase chain reaction for offspring from a breeding study where offspring were raised under different lighting conditions. Sire (i.e. genetic) effects were present for opsin found in yellow photopigment. Dam effects were present for opsins that create violet, blue and red photopigment. Lighting conditions affected expression of all opsins except SWS2A and mimicked the pattern found among populations. These results highlight the fact that sensory systems are both plastic and yet readily evolvable traits.