Painting Wings - Evidence for a Role of Ca$^2$$^+$ in Butterfly Wing Phenotypic Plasticity

Abstract

Wing patterns in butterflies serve several functions such as mimicry, sexual dimorphism, camouflage, and temperature regulation. Based on temperature adaptations by butterflies involving change in brightness and calcium mediated temperature responses. Here, we investigate the role of calcium in mediating the expression of light and dark scales. Through utilization of the butterfly Vanessa cardui as a model, I investigated how fluctuations in cytosolic calcium levels can potentially influence the development of wing brightness. Specimen brightness was manipulated with tungstate and thapsigargin injections. Tungstate has been shown to modify butterfly wing patterns but its mechanism of action has yet to be identified. Thapsigargin is a well-studied drug known to result in increases of cytosolic calcium similar to that of natural heat responses. Through utilization of these compounds, my hope was to reach a better understanding of the specific ways in which wing patterns are regulated by calcium. The specimens manipulated with pharmacological injections of thapsigargin showed an increase in the number of light scales within the injected area. Alternatively, specimens injected with tungstate showed a larger proportion of dark scales. Overall, findings suggest that calcium potentially plays a significant role in organizing wing pattern development.