Wasps are building fluorescent nests

 Wasps are building fluorescent nests

A team of scientists say they have come across the first known case of animals building fluorescent houses. In a new study, they detail the finding of nests built by certain species of wasps that glow green under exposure to ultraviolet light. What's more, wasps of the same family in other parts of the world also appear capable of creating similarly creepy structures.

The discovery occurred during an expedition to northern Vietnam, but not intentionally, according to the scientists. Study author Bernd Schöllhorn, a professor of chemistry at the University of Paris, told Live Science that they traveled with ultraviolet lights in the hope of stumbling upon any fluorescent bugs after dark. Instead, they found wasp nests with cocoons (woven silk structures that cover the nest and keep the larvae safe) that emitted a bright mucus-green glow when exposed to ultraviolet light between 360 and 400 nanometers wavelength at night. Like any good researcher, they took some samples back to the lab for further study.

"We were very surprised to find such strongly fluorescent biomatter," Schöllhorn told Live Science. "As far as we know, this phenomenon has not been observed in the past, neither by scientific researchers nor by photographers."

All of the glowing nests they found belonged to species of the wasp genus Polistes, also commonly known as paper wasps. When they acquired nests from two other Polistes species living in the Amazon rainforest and in France and put them under ultraviolet light, they found that these nests also glowed, although all the nests were slightly different in intensity and color from each other. The team's findings were published this week in the Journal of the Royal Society Interface, and images of the various glowing nests can be seen here in their supplementary material.

Although glowing under a black light might be seen as an exotic trait, scientists have discovered a growing list of creatures from different branches of life that have this unexpected ability, including some mammals. But they are still trying to figure out the reasons why it would be worth evolving fluorescence in the first place. The fluorescent nest could help wasps navigate back home, for example, or allow them to distinguish one nest from another. It may also aid larval development, as the glow could act as a surrogate light source during the rainy season. It could even be an incidental or vestigial trait that never served any purpose, or has since lost its purpose, but remains present because it does not harm the wasps.

The researchers plan to continue studying these wasps and their glowing homes in order to unearth the chemicals that make them fluorescent. From there, they hope to find out if these ingredients could have any application for human use, such as a new fluorescent marker for research or medical imaging.