The two nature news that made headlines last week are the discovery of a fluorescent frog in Argentina and the glowing sea shores of Tasmania. While both these events had no direct relation to each other, according to biologists, they represent the two sides of a coin, namely, biofluorescence and bioluminescence.
Biofluorescence is the phenomenon where an organism absorbs low wavelength light (dim light) and emits high wavelength light that makes it glow against a dark background. On the contrary, bioluminescent organisms emit light form their body (parts) due to some specific chemical reactions. The chemistry behind both these phenomena has been explored in great detail since long. However, the exact ecological and evolutionary implications of emitting/reflecting light are more or less vague.
Over the years, biologists have discovered many fluorescent organisms on land and some even under the sea. Some of the most common examples of fluorescent organisms include corals, fishes, sharks, parrots, hawksbill turtle, scorpions and some insects. The most recent addition to this list is Hypsiboas punctatus, a polka dot tree frog collected near Santa Fe, Argentina, that glows bright green in black and ultraviolet (UV) light, Nature reported.
Meanwhile, scientists and naturalists flocked to the Tasmanian beach few days ago to witness and study it when it glowed bright blue at night. The glowing seashore phenomenon is considered as a nature's visual delight. It occurs due to the phytoplankton Noctiluca scintillans, which glows upon stimulation, most often by the waves, The Marshall Town reported.
The fact of the matter is, apart from these glowing seashores and a few terrestrial biofluorescent organisms like fireflies, most of the other glowing species are deep sea dwellers. The ability to produce light (mostly red light) is considered an adaptation for the survival of these fishes. Dragonfish is one such bioluminescent deep sea organism that produces red light. According to marine biologists, the Dragonfish uses its red light to spot its prey and communicate with others of its kind, Wildscreen Arkive reported.
According to Deep Sea News, biofluorescent organisms like parrots and red-eyed wrasse use fluorescence to attract mating partners. While others, like the frogfish, use it to attract preys. On the other hand, some scientists are of the opinion that biofluorescence, especially in marine organisms, is " a quirky side-effect of evolution that serves no real purpose."
The scientific community is still trying to comprehend the real-time advantages and disadvantages of "bioluminescence vs biofluorescence" in various organisms. Hopefully, mankind succeeds in understanding the reason behind these stunning beautiful phenomena.