Many birds-of-paradise species emit light through their plumage

Most species of birds-of-paradise are biofluorescent — parts of their body and their feathers can absorb UV or blue light and emit it back out at different frequencies — which makes their colours more vibrant. Of the 45 species, researchers found that 37 showed biofluorescence, with glowing body parts differing between males and females. Researchers theorise that the phenomenon would enhance courtship displays in males, whereas it seems more likely to be a camouflage aid in females.