Arrangements of material at the nanometer scale produce a dazzling array of colors, ranging from

ultra violet to red, without pigments. These so-called structural colors are particularly distinctive in

birds, which can produce non-iridescent colors (such as the blues of blue tits) using matrices of

keratin and air, or iridescent colors (such as the flashy colors of hummingbirds) using arrays of

melanin-containing organelles called melanosomes. Several hypotheses on how these materials

grow during feather development have been proposed, but none has been tested. Moreover, these

materials have numerous potential uses in optical fibers, displays and replacements for

environmentally harmful pigments. We propose to test hypotheses on nanostructural development

using biomimetic approaches. First, we will produce synthetic melanosomes that closely mimic

those found in birds, including hollow and flattened morphologies unique to birds, and allow them

to self-assemble under various conditions. We predict that they will from 1-2 dimensionally

organized iridescent structures. Second, we will produce both natural and synthetic polymer blends

that, through well-known processes, self-assemble into non-iridescent semi-organized structures.

Finally, we will use nanoscale 3D printing to produce both iridescent and non-iridescent structures.

These results will improve our understanding of nanostructural self-assembly and may lead to novel

and useful low-cost optical materials.