Diverse nanostructures underlie thin ultra-black scales in butterflies.

Published

Journal Article

Recently, it has been shown that animals such as jumping spiders, birds, and butterflies have evolved ultra-black coloration comparable to the blackest synthetic materials. Of these, certain papilionid butterflies have reflectances approaching 0.2%, resulting from a polydisperse honeycomb structure. It is unknown if other ultra-black butterflies use this mechanism. Here, we examine a phylogenetically diverse set of butterflies and demonstrate that other butterflies employ simpler nanostructures that achieve ultra-black coloration in scales thinner than synthetic alternatives. Using scanning electron microscopy, we find considerable interspecific variation in the geometry of the holes in the structures, and verify with finite-difference time-domain modeling that expanded trabeculae and ridges, found across ultra-black butterflies, reduce reflectance up to 16-fold. Our results demonstrate that butterflies produce ultra-black by creating a sparse material with high surface area to increase absorption and minimize surface reflection. We hypothesize that butterflies use ultra-black to increase the contrast of color signals.

Full Text

Duke Authors

Cited Authors

  • Davis, AL; Nijhout, HF; Johnsen, S

Published Date

  • March 10, 2020

Published In

Volume / Issue

  • 11 / 1

Start / End Page

  • 1294 -

PubMed ID

  • 32157090

Pubmed Central ID

  • 32157090

Electronic International Standard Serial Number (EISSN)

  • 2041-1723

International Standard Serial Number (ISSN)

  • 2041-1723

Digital Object Identifier (DOI)

  • 10.1038/s41467-020-15033-1

Language

  • eng