The Purest White Ever Seen, Found in Beetles
When you think of the purest white, you likely picture obscure concepts such as truth, innocence, or even angels. If you're an entomologist, however, you could just as likely be thinking of beetles. Researchers have recently determined that two types of beetles have shells that reflect light so well, they appear whiter than the whitest paper.
According to a study recently published in the journal Scientific Reports, the chitinous scales of the Cyphochilus and Lepidiota stigma beetles are structured in such a way that they perfectly reflect light of all colors anisotropically - meaning that the reflected light all bounces in one direction. The result is that the human eye sees a remarkably brilliant white color.
"These scales have a structure that is truly complex, since it gives rise to something that is more than the sum of its parts," researcher Matteo Burresi of the Italian National Institute of Optics in Florence told New Scientist. "A randomly packed collection of its constituent elements by itself is not sufficient to achieve the degree of brightness that we observe."
The study details how both these beetles, which hail from Southeast Asia, could have been developing whiter shells to meet one or several of "an amazing range of optical strategies." Among insects, bright and reflective exoskeletons allow species to communicate, display for mating, and even blend in with their surroundings. It is theorized, for instance, that the while scales of the Cyphochilus may have developed its pure color to blend in with the white mushrooms that scatter their natural habitats. While they may look significantly brighter than the mushrooms to human eyes, the beetles' more natural predators may see things a little differently.
Lead researcher Silvia Vignolini told the Daily Mail that the perfect storm of mutation and natural selection that made these incredibly reflective scales may teach industry a thing or two.
"Current technology is not able to produce a coating as white as these beetles can in such a thin layer," she said.
The authors of the study now suspect that synthesizing the chitin structure seen in these beetles could help make papers, plastics and paints a brighter white. Light reflectors in television displays would also be made more efficient if adequately adapted.