A paper out in PLoS ONE last month announces the discovery that a lot more fish fluoresce than we thought. 180 species of fish biofluoresce, with emission colors ranging from greens to reds: eels and rays are in the greens while scorpionfish and gobys are fairly red and others are in between.

The authors consider several evolutionary advantages that biofluorescence might bestow on these species. Some fish may use it to blend in with fluorescent corals, others may use it to communicate. Certain deep sea fishes are thought to use fluorescence to lure prey.

What really gets me excited about this paper isn't the fish, though. It's the fluorophores.