The blue color of the fruit of viburnum eurolites has a structural origin. The researchers found that close to surface underlain by a layered structure with the lipid vesicles, which reflects light in the blue and ultraviolet part of the spectrum. Additional saturation of color gives a dark red pigment anthocyanin, it absorbs the light, which was able to bypass the reflective layer. As noted by the authors in an article for the journal Current Biology, lavalina Kalina, the first known plant with this type of structural coloration.
The fruit of many plants painted in bright colors, which serve as a is for animals — distributors of seeds. For example, eurolites drupe viburnum (Viburnum tinus), a popular ornamental shrub native to the Mediterranean, has an unusual dark blue shade with a metallic sheen. It attracts small passerine birds that feed on fruits of this species in the winter months and spread its seeds.