Most diverse bioluminescent vertebrate group

No other discrete taxonomic group of vertebrate animals exhibits bioluminescence (the production of light by a living organism) among more of its species than the ray-finned fishes (class Actinopterygii), with up to 80% of open-water marine fish boasting the ability to some degree. Research has shown that bioluminescence has evolved independently 27 times among ray-finned fishes alone, with that number rising to 29 times if rays and sharks (class Chondrichthyes) are included. Ray-finned fish are a very diverse group comprising more than 430 families, and around 27,000 of the total ∼32,000 species of extant fish; bioluminescent examples from the group include anglerfish, hatchetfish, toadfish, gulper eels, lanternfish and dragonfish, all of which are either deep-sea dwellers or nocturnal species that use their self-made light for various purposes including luring prey, confusing predators and for courtship displays. The study that brought these findings to light was published in PLOS ONE on 8 June 2016.

Until recently, it was thought that bioluminescence had evolved no more than 40 times across the entire tree of life, but that now seems unlikely given the prevalence of convergent evolution among marine fish alone.

Other types of organism to exhibit bioluminescence are insects such as fireflies and glow-worms, jellyfish and even fungi.

The study was a collaboration between St Cloud State University, the American Museum of Natural History and University of Kansas (all USA), led by Dr Matthew Davis of St Cloud State University.