Seasonal Wing Pattern Variation in a Central Indiana Population of the Cabbage White Butterfly (Pieris rapae)

Indianapolis, IN

Environmental changes affect the phenotype displayed by many organisms. In the case of the cabbage white butterfly and other related butterflies, wing patterns vary seasonally. Previous research indicates that changes in daylength and temperature experienced during development cause variation in wing patterns. However, it is still unclear whether wing pattern variation strictly follows seasonal temperature averages, or whether butterflies captured at similar temperatures from different seasons would be phenotypically unique from one another. The difference in seasonal wing pattern variation between the sexes is also still unknown. Furthermore, it is still unclear how short-term unseasonal weather patterns affect wing pattern variation and if all wing pattern traits show the same seasonal variation. This study aims to quantify several wing pattern traits from several hundred butterflies captured in Marion and Hamilton counties over the past three years. We will examine sources of variation within seasons, such as warm and cold spells and create a detailed seasonal profile of wing pattern variation. Our results will provide a reference point for future collections that will examine wing pattern variation in response to climate change, and as a reference point for comparing populations from other regions.