| The development and evolution of veins and color patterns found on the wings of the Lepidoptera are intimately related, but until recently there were no molecular tools available to study the relationships between these structures. Over the last ten years, reagents have been developed to study one type of lepidopteran color pattern element, the border ocellus. However, the many other color pattern elements have received relatively little attention. The development of one of these patterns, the discal spot, is intimately associated with the development of the discal crossvein, a structure that has an important role in determining the flexural stiffness of insect wings. For my dissertation research, I have studied the development of a homologue of the discal crossvein in a genetic model organism, the fruit fly Drosophila melanogaster . Using a variety of techniques that are available in Drosophila , I have developed a model for crossvein formation in this species and I have identified a number of loci, which may be useful for studying crossvein development in the Lepidoptera as well. Using this model for crossvein development, I have generated two hypotheses for how the development of crossveins and the color patterns that are associated with them may be related. Finally, I use this knowledge of crossvein formation to illuminate the examination of the unusual discal spots found in the lepidopteran family Saturniidae. Some of the moths in this family have discal spots, which resemble the border ocelli of other lepidopteran species. The developing discal spots in these species express molecular markers for border ocelli at the location of the developing discal spot, while other species in the same family which have more typical discal spot pigmentation do not express these markers. |
