Biofluorescence in Marine and Terrestrial Organisms

Biofluorescence is the phenomenon by which living organisms absorb incident light at high energy wavelengths and reemit it at longer, lower-energy wavelengths. This optical process has been documented across a broad spectrum of life, from cnidarians and fishes in the marine realm to amphibians, reptiles and even mammals on land. In marine ecosystems, biofluorescence contributes to species-specific signalling, camouflage and prey attraction under predominantly blue lighting conditions, while in terrestrial settings it may play roles in intra- and inter-specific communication, sexual selection and predator avoidance. Molecularly, biofluorescence often involves fluorescent proteins or organic compounds such as porphyrins, and is modulated by specialised cells or anatomical structures—chromatophores in fishes or thin cuticular windows in reptiles. Across taxa, biofluorescent patterns exhibit substantial phenotypic variability, reflecting diverse evolutionary origins and ecological functions. Recent advances have begun to reveal the visual adaptations that enable organisms to perceive fluorescence, including yellow long-pass filters in fish eyes and ultraviolet-sensitive receptors in amphibians. As methodological techniques improve, the global significance of biofluorescence is emerging not only for basic ecological and evolutionary research but also for potential applications in bioimaging and biodiversity monitoring.

Research from Nature Portfolio

Recent studies have revealed the first instance of biofluorescent sexual dimorphism in a salamander species, where males and females of a southern Appalachian endemic exhibit distinct green fluorescent patterns associated with ventral glands potentially used in chemosensory communication. In mammals, vivid biofluorescence has been documented in the springhare, marking the first report in an Old World placental species; fluorescence originates within the hair cuticle and is partly attributed to porphyrin compounds, with striking visual contrast under crepuscular illumination. In terrestrial reptiles, bone-based fluorescence has been shown to be widespread in chameleons, where bony tubercles protrude beneath a thin epidermal layer to emit blue fluorescence; the number and distribution of these tubercles are sexually dimorphic and correlate with habitat-specific ambient ultraviolet levels, suggesting a role in visual signalling and species recognition.

Biofluorescence in Marine and Terrestrial Organisms publication trend

The graph below shows the total number of articles in biofluorescence in marine and terrestrial organisms across all publications each year (not limited to Nature Index journals).

Technical terms

Biofluorescence: The absorption of light at one wavelength by an organism and its reemission at a longer wavelength.

Fluorescent Protein (FP): A protein that exhibits fluorescence, often used by organisms to produce coloured emissions under excitation light.

Excitation Wavelength: The specific light wavelength absorbed by a fluorophore, initiating the emission process.

Emission Wavelength: The longer wavelength at which a fluorophore reemits absorbed light.

Chromatophore: A pigment-containing or light-reflecting cell that can regulate the distribution of fluorescent or pigmented materials in the integument.

References

1. Biofluorescent sexual dimorphism revealed in a southern Appalachian endemic salamander, Plethodon metcalfi. Scientific Reports (2023).
2. Vivid biofluorescence discovered in the nocturnal Springhare (Pedetidae). Scientific Reports (2021).
3. Widespread bone-based fluorescence in chameleons. Scientific Reports (2018).
4. The Covert World of Fish Biofluorescence: A Phylogenetically Widespread and Phenotypically Variable Phenomenon. PLOS ONE (2014).
5. Fluorescent proteins function as a prey attractant: experimental evidence from the hydromedusa Olindias formosus and other marine organisms. Biology Open (2015).
6. A Fluorescent Chromatophore Changes the Level of Fluorescence in a Reef Fish. PLOS ONE (2012).