Jerome Mallefet/National Fund for Scientific Research, Catholic University of Louvain)
While bioluminescence — the ability to glow in the dark — is a fairly common occurrence in fish and squid that live in the ocean's darkest depths, its presence in sharks is not as well-documented or understood. Now, the discovery of the largest-known luminous vertebrate — the six-foot-long kitefin shark — and two other glowing shark species has enabled researchers to gain valuable insights into the luminescent abilities of the deep-sea creatures.