Damselflies boost color saturation by using pigments and changing how light moves through materials

What is it about?

This study explores how damselflies produce very bright, saturated body colors using tiny, disordered structures in their skin known as photonic glasses. Photonic glasses are disordered assemblies of nanometric spheres (like tiny ball pits) that can produce colors. These natural structures normally have a built‑in limit on how intense their colors can be, but we show that damselflies get around this limit in two main ways. First, they load the spheres with pigments that selectively absorb certain wavelengths of light. Second, they subtly change the refractive index (how fast light travels) of the spheres by changing their density. We also find that the damselfly’s color change from green to blue happens when the spheres that make up the photonic glass shrink in size. The shrinking of the particles, along with changes in their material properties and pigment content, are all tuned together in a coordinated way. This coordination naturally produces very vivid colors without the need for a perfectly ordered, crystal‑like structure.

Featured Image

Photo by Jamie Frith on Unsplash

Photo by Jamie Frith on Unsplash

Why is it important?

Our work helps explain how insects evolve striking colors for communication and camouflage, and it could inspire new strategies for making bright, stable colors in materials and coatings without relying on traditional chemical dyes.

Perspectives