The team also noted that many biofluorescent fishes have yellow filters in their eyes, possibly allowing them to see the otherwise hidden fluorescent displays taking place in the water. Although more research is needed, this finding indicates that biofluorescence could be used for interspecific communication while remaining camouflaged to predators. This ability might be especially important during full moons, when fishes have been shown to partake in mating rituals.
"The cryptically patterned gobies, flatfishes, eels, and scorpionfishesthese are animals that you'd never normally see during a dive," Sparks said. "To our eyes, they blend right into their environment. But to a fish that has a yellow intraocular filter, they must stick out like a sore thumb."
In addition, the research revealed that fish biofluorescence is extremely variable, ranging from simple eye rings to glowing green mucus secreted on the outside of fishes to complex fluorescent patterns throughout the body, including internally, suggesting that the ability to glow evolved a number of times in fishes. Further study on the mechanics of this phenomenon could uncover new florescent proteins for use in experimental biology.
"The discovery of green fluorescent protein in a hydrozoan jellyfish in the 1960s has provided a revolutionary tool for modern biologists, transforming our study of everything from the AIDS virus to the workings of the brain," Gruber said. "This study suggests that fish biofluorescence might be another rich reservoir of new fluorescent proteins."
|Contact: Kendra Snyder|
American Museum of Natural History