This is the third talk in the series “Science and Aesthetics” and this time we examine the science and beauty of Lepidoptera, the order of insects that includes butterflies and moths. The striking colors of butterflies and moths have been crucial for their survival for more than 200 million years, and the design of the wing patterns serves as camouflage, warning and attracting mating partners. In many butterflies and moths, the wings’ color come from pigments. In other cases, coherent scattering and interference of light produce the wings’ color by the microstructure of the ribbon-like scales covering the moth's wings. In this talk, we will examine the physical principles that create the colorful wing patterns. We will also have close look at insect that are used to make dyes for several industries.