Changing Colors is an interactive exhibit that shows how some high-tech nanomaterials mimic natural phenomena. Super-small, light-reflecting structures—instead of pigments—on the wings of some butterflies create intense, iridescent colors. Nanoscientists have replicated this effect with layered, super-thin films. Watch the colors change on butterfly wings and thin-film slides as you move them beneath a light source, and discover how nanoscale structures can manipulate light and create color. Butterfly specimens deteriorate with heavy use, and may need to be replaced periodically.