While diving near the Solomon Islands recently, biologist David Gruber saw a hawksbill sea turtle glowing neon red and green. This turtle, he told National Geographic, may be the first reptile ever observed exhibiting biofluorescence, a sometimes-fishy phenomenon in which light is absorbed, transformed, and re-emitted as a different color.
On Sept. 28, National Geographic posted exclusive video footage of the discovery.
Biofluorescence is distinct from bioluminescence, in which an organism simply produces light through a chemical reaction. Marine mammals are sometimes observed “glowing” underwater when they are surrounded by bioluminescent plankton.
Gruber, who is a City University of New York professor and a National Geographic “emerging explorer,” is currently co-producing a 3D IMAX film about bioluminescence.
After spotting the fluorescent hawksbill, Gruber spoke with local residents and was introduced to several captive turtles of the same species. All glowed red when he tested them for biofluorescence.
No one knows why these turtles have this ability. And unfortunately, since the hawksbill sea turtle is critically endangered, there may not be much opportunity to find out.