With the help of blue light and special long-pass filters, scientists have uncovered more of the undersea world's secrets. A study published Saturday describes more than 180 species of marine fishes that glow in different colors and patterns, via a process known as biofluorescence. The work was funded by the National Science Foundation.

 

Scientists already knew that some marine organisms fluoresce, including corals and jellyfish, but this is the first reported evidence of widespread biofluorescence among fishes.

 

The findings, published in PLOS ONE, will surely lead to new investigations of the function of biofluorescence as well as research related to the evolution and diversification of marine fishes. They could also lead to the discovery of new fluorescent proteins useful in cancer, brain and other biomedical research.

 

Biofluorescence is a natural process in which organisms absorb light at one intensity, or wavelength, and emit it at a different, usually lower, level--seen as a different color. In the ocean, the researchers found, fishes absorb the higher energy blue light around them and emit it in glowing greens, reds and oranges.

 

How did the scientists make the discovery? While taking and processing images of biofluorescent coral for an NSF-funded traveling museum exhibit: Creatures of Light: Nature's Bioluminescence, Sparks and AMNH research associate David Gruber (CUNY) were amazed to see, in the background of one image, an eel glowing bright green.

 

The researchers identified biofluorescence in 16 orders, 50 families, 105 genera and more than 180 species of fishes. These include the two main fish groups: cartilaginous (sharks and rays) and bony fishes (eels, lizardfishes, gobies, flatfishes).