A small arachnid known as the peacock spider could help lead to more efficient technology, according to a recent paper published in the journal Nature Communications.
When a male peacock spiders wags its bottom at a potential mate, it diffracts intense iridescent light that shimmers with a range of different colors. Scientists call the unique display “nature’s smallest rainbow,” and it is the only known natural example of males using rainbow colors to entice females during courtship.
Though the mechanisms behind the unique display has been a mystery for some time, a team of international researchers now believe they have found how two species of miniature peacock spiders — Maratus robinsoni and Maratus chrysomelas — create the dazzling display: scales
“M. robinsoni and M. chrysomelas have two types of visually distinct abdominal scales: rainbow-iridescent scales and velvet black scales,” the researchers wrote in their new paper, according to Live Science. “These scales show strikingly different morphologies: The black scales are brush-like and randomly oriented, while the rainbow-iridescent scales are more orderly aligned, cling to the cuticle surface and have bulky 3D shapes.”
To get a closer look at the arachnids, the researchers used different imaging techniques to better understand the scales rainbow-scattering properties. That revealed each iridescent scale contains a series of three-dimensional, parallel grates that split different wavelengths of light at different angles. Such a configuration disperses the visible spectrum over a small angle, which then helps create a rainbow pattern.
These findings helped researchers create their own miniature rainbow-scattering surfaces. As a result, understanding the scales could help create better optics and color technology, including instruments on space missions or wearable chemical-detection systems.
Though more research has to be done before that point is reached, there is no doubt that a better look at the rainbow scales will come with many benefits down the line.
“As an engineer, what I found fascinating about these spider structural colors is how these long-evolved, complex structures can still outperform human engineering,” said study co-author Radwanul Hasan Siddique, a postdoctoral scholar at the California Institute of Technology, in a statement. “I wonder how the spiders assemble these fancy structural patterns in the first place.”