Why Deep In the Forests of Vietnam, Wasp Nests Glow Green
This recent discovery yields surprising new information on fluorescence use by insects
It sounds like something you might find in a science fiction story, but fluorescent creatures are out there. Researchers investigating fluorescence in Vietnam recently discovered that Asian paper wasps emit a green glow under ultraviolet light.
Their findings, recently reported in the Journal of the Royal Society Interface, show that the green light comes from silk fibers in the nests of the Asian paper wasp Polistes brunetus, return about 35% of the light they absorb. This means they can be seen from up to 20 meters away, even without a hand-held UV light in your pocket.
The silk threads the wasps use to build their nests are some of the brightest natural-occurring fluorescent materials found to date. Researchers think the wasps may benefit by using the nests to absorb UV radiation, protecting the larvae inside from harmful energy and dissipating the radiation as a soft green light.
Another hypothesis is that the wasps use glow of the sun’s ultraviolet light hitting the nests to find their way back home. Since the wasps forage for food during the day many hundreds of feet from their nest, they may use the light of the glowing nests as a beacon drawing them back to the hungry offspring.
While we don’t totally understand why wasps in these forests are able to build ultraviolet fluorescing nests, it’s still one of the coolest things to be found this year.
