Nature & Environment

Nature's smallest rainbow found on tiny spider

By T.K. Randall
January 4, 2018 ·  3 comments

Peacock spiders perform an elaborate dance to attract a mate. Image Credit: CC BY-SA 2.0 Jurgen Otto Native to Australia and measuring a mere 0.2 inches long, this unusual arachnid is unique in that it is the only creature on Earth to use all the colors of the rainbow to entice females during courtship.

The display involves shaking its glittering, iridescent posterior in the direction of any lady spiders that happen to be watching - a spectacle that has become known as "nature's smallest rainbow."

In a recent study, researchers from the United States, Belgium, the Netherlands and Australia attempted to determine exactly how these spiders manage to pull off such a colorful display.The answer, as it turns out, lies in the peacock spider's unique scales.

"M. robinsoni and M. chrysomelas ( two species of peacock spider ) have two types of visually distinct abdominal scales: rainbow-iridescent scales and velvet black scales," the researchers wrote.

"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."

"The unique grating configuration of each M. robinsoni scale disperses the visible spectrum over a small angle, such that at short distances, the entire visible spectrum is resolved, and that a static microscopic rainbow pattern distinctly emerges."


Source: Live Science | Comments (3)

Tags: Peacock Spider, Rainbow