Wing Shape and Color Pattern Modifications in Giant Silk Moths Using Sulfated Polysaccharides: Understanding...

The tails and conspicuous eyespots of many saturniid moths are outstanding examples of anti-predator adaptations. These features vary intra- and interspecifically, and while there are hypotheses regarding the selective pressures that maintain these variations, there is little empirical information regarding the genetic and developmental mechanisms that control them. Exogenous chemical substances, like sulfated polysaccharides, can affect the expression of various genetic pathways, including those determining wing patterns. This study leveraged the effects of heparin and dextran sulfate, acting as agonist and antagonist of extracellular Wnt/wingless signaling, respectively, to consistently create aberrant wing shapes and patterns in Luna and Polyphemus Moths. Hindwing tails and eyespots were expanded and contracted by heparin and dextran sulfate, respectively, creating a framework for subsequent investigations into the genetic origins of hindwing tail shape and eyespots. This hidden variation could aid in fast adaptive evolution; revealing it provides a framework for investigating homologies and evolutionary development. Experimentally inducing changes to wing shape in a Lepidoptera species also opens the realm of morphological control: the creation of Luna Moth individuals with significantly wider or narrower hindwing tails may help in quantitative linking of wing shape and flight in future research.