Strange wasp nests glow neon green under UV light


Image on the left shows a wasp nest and wasps under white light; image on the right shows the same nest under UV light and parts of the nest are glowing bright green (Image credit: Bernd Schöllhorn and Serge Berthier)

While trekking through the tropical forests of northern Vietnam, scientists unexpectedly discovered wasp nests that glow fluorescent green under ultraviolet light.

The nests, which look like a cluster of hexagonal cells, were built by several species of paper wasp, all belonging to the genus Polistes. The wasps seal off the underside of the hexagonal cells with so-called cocoon caps made of silken fibers, which protect the growing larvae within the nest. And for reasons yet unknown, these cocoon caps emit a strong greenish-yellow glow when exposed to UV light between 360 and 400 nanometers in wavelength.