10 brief facts on bioluminescence

We all get excited thinking about bioluminescence in nature. Ironically, that excitement is only one of the reasons animals glow like an elf in Middle Earth. Here are some ‘basics on bioluminescence’ you can share with your friends and family the next time you all ogle a firefly and wonder ‘why?’.

    1. Insects (e.g., fireflies, glow worms) and deep sea ocean animals (e.g., squid, hatchetfish) aren’t the only ones that emit light. Many plants (e.g., jack-o’-lantern mushroom, algae) also produce bioluminescence.
    2. Bioluminescence is light emitting from a living organism. Bioluminescence is produced through a chemical reaction, which is what sets is apart from fluorescence or phosphorescence.
    3. Luciferin and luciferase are the two chemicals that must be present for an organism to luminesce. Luciferin produces the light and luciferase is the catalyst. Life in the sea most often use coelenterazine, a type of luciferin.
    4. Sailors commonly saw waves glowing in the wake of ships. This was caused from dinoflagellates, a single-celled algae, which glows when its startled.
    5. Anglerfish use a long illuminated appendage, called a protuberance, to attract young and vulnerable prey. Luring prey is one way bioluminescence is used to an animal’s advantage. They may also use it to stun prey or to attract or recognize a mate.
    6. Conversely, many animals use bioluminescence as a defense mechanism. They’ll cleverly create smoke screens or burglar alarms, as well as counterilluminate or startle predators.
    7. Some animals that luminesce use it defensively and offensively.
    8. Sperm whales, the deepest divers of all the whales, depend on bioluminescence to help locate food. Echolocation is also key to locating food.
    9. The U.S. Navy tapped into the science community for help to develop products that monitor bioluminescence because bioluminescent algae have been known to endanger military missions.
    10. The pulsing light of creatures found in the deep sea is “perhaps the most common form of communication found on our planet”. That phrase was from a video (below) which takes us on a visual journey of what the first deep sea explorer, William Bebe, described in 1934 from his expedition off the coast of Bermuda. This video was produced by National Geographic.

What is bioluminescence?

Bioluminescence means light (as in ‘illuminate‘) from life (prefix ‘bio‘).

It is produced by a chemical reaction in many marine or terrestrial organisms. The reaction begins with a chemical called luciferase that catalyzes another chemical, luciferin, to then make oxyluciferin and light.

If you see bioluminescence from a boat it is most often tiny dinoflagellates near the surface of the water that begin this chemical reaction once they’re excited. A boat or a passing porpoise can trigger this excitement. On land we are familiar with bioluminescence in fireflies and a glowing fungus, called foxfire.

But, did you know bioluminescence is responsible for illuminating the majority of our habitable world? That’s right, the deep sea is the largest area of habitable space on our planet. A large number of species that utilize this adaptation live in that environment. Here are some images of the inhabitants of the deep sea that use bioluminescence:

Deep sea shrimp, Acanthephyra purpurea

Deep sea fish, Photostomias guernei

Blackdevil angler fish, Melanocetus johnsonii

All images (c) NOAA.