# Birds of Paradise: Nature’s Living Glowsticks
Birds of paradise are renowned for their lavish feathers and captivating courtship performances, but recent studies uncover an additional stunning feature they possess—biofluorescence. Researchers have identified that these birds, native to Papua New Guinea, Indonesia, and Eastern Australia, emit a glow when exposed to ultraviolet (UV) light, contributing another layer of intrigue to their already remarkable displays.
## The Glow Factor
Biofluorescence is an occurrence where living organisms absorb short-wavelength light (like UV or blue light) and re-radiate it at longer wavelengths, often appearing green, yellow, or red. Though this characteristic is common among marine species, amphibians, and some fungi, it has seldom been recorded in birds.
Biologist Rene Martin from the University of Nebraska-Lincoln and her team recently studied museum specimens of birds of paradise under UV light and found that 37 out of 45 recognized species displayed biofluorescence. The glowing feathers were particularly pronounced in males, especially on their heads, necks, chests, and abdomens. Even their feet and the interiors of their mouths glowed under UV light.
## Why Do They Glow?
The research team posits that biofluorescence is significant for mating displays. Males of various bird of paradise species already utilize their vivid colors and intricate dances to allure females, and the capacity to glow may provide them with an additional advantage in courtship.
Nonetheless, biofluorescence might have other functions as well. Some birds may employ it for communication, signaling to competitors or potential partners in ways that are undetectable to human observers. In specific circumstances, it could also offer camouflage, assisting birds in blending into the mottled light of the rainforest canopy.
## The Science Behind the Glow
The source of this glowing phenomenon lies in unique molecules known as fluorophores, which absorb high-energy UV light and re-emit it as lower-energy wavelengths. Birds of paradise have adapted specific filters in their eyes that boost their sensitivity to these fluorescent signals, enabling them to perceive colors that many other animals cannot.
## The Role of Habitat and Behavior
The degree of biofluorescence is affected by a bird’s habitat. Birds of paradise that inhabit the upper canopy, where more UV light reaches, generally exhibit stronger fluorescence than those residing nearer to the forest floor.
Behavior is also influential. The Western parotia (*Parotia sefilata*), for instance, prepares a clear section of the forest floor prior to showcasing its elaborate courtship dance. Researchers believe this action may help minimize background distractions, allowing the male’s glowing feathers to be more pronounced.
## Super Black Feathers: The Perfect Contrast
One of the most remarkable attributes of birds of paradise is their “super black” feathers that absorb nearly all light, generating a deep contrast against their vivid colors. Martin’s research team discovered that species with the darkest feathers also exhibited the most intense biofluorescence, indicating that these two attributes may have co-evolved to enhance visual displays.
## A Widespread Phenomenon?
While birds of paradise are the initial group of birds thoroughly examined for biofluorescence, researchers speculate that many other species might also exhibit glowing traits under UV light. Certain parrots, owls, nightjars, penguins, and puffins have already been recognized as biofluorescent, and scientists anticipate many more yet to be identified.
For instance, the Moluccan cockatoo (*Cacatua moluccensis*), a predominantly white parrot indigenous to Indonesia, coexists with some birds of paradise. Although its biofluorescence has not been investigated yet, it could offer valuable insights into the prevalence of this feature among birds.
## Conclusion
The revelation of biofluorescence in birds of paradise adds an intriguing new facet to our comprehension of these already amazing creatures. As scientists delve deeper into the unseen colors of the avian realm, we may discover that nature’s light display is even more astonishing than we ever envisioned.
For more information, refer to the complete study published in *Royal Society Open Science* (DOI: [10.1098/rsos.241905](https://doi.org/10.1098/rsos.241905)).
