Bioluminescence: When nature glows in the dark
View(s):How Bioluminescence works:
You carry a torch to help you see in the dark, but some animals become their own torches. In luminescent animals, chemical compounds mix together to produce a glow. The process neither requires nor generates much heat, so it’s sometimes known as cold light.
Is it to help them mate, to find food or better camouflage them from predators?
We don’t fully understand why bioluminescence developed. For instance, why do mushrooms glow? It might be because insects are attracted to the plant and help it spread its spores. Some animals don’t create their own light instead they have a relationship with light
producing bacteria they keep in a ‘light organ’ in their own bodies.
The bacteria produce light all the time, so in order to turn their lights on and off, some animals can pull their light organs into their bodies. Others cover them with pieces of skin similar to eyelids.
Bioluminescence in the Natural World
l Hundreds of metres down, in deep, pitch-black ocean waters, monstrous-looking anglerfish wave about bioluminescent lures, called esca, to tempt prey into swimming within striking distance. Like fireflies, these common, deep water fish may use the
lighting effects in mate selection, as well.
l Tides, storms, swimming marine life and passing ships can cause large numbers of these plankton to produce light simultaneously. Dinoflagellates are responsible for the phenomenon known as the milky sea, which causes the ocean to glow. In some cases, this glow is so bright that it interferes with marine navigation.
l Last year, five previously unknown species of sea worm were discovered that launched liquid-filled, bioluminescent capsules that burst into green light for several seconds. Scientists think these “bombs” distract piscine predators; they have seen similar counter
measures deployed by both squid and brittle stars.
l Mushrooms gleam in forests all over the world, from the Mycena lucentipes species seen here, described in Brazil last year, to the honey and jack o’ lantern mushrooms that emit a greenish “fox fire” glow in woodlands Researchers have now documented more than
70 species of bioluminescent fungi, although the exact purpose of the ‘shrooms’ bioluminescence remains mysterious.
l Dozens of earthworm species from all over the world can secrete a glowing slime, thought to startle predators. This particular worm, Diplocardia longa, is found in sandy soils in southern Georgia in the U.S. and can stretch to over half a metre in length.
Though you’ll see glowing centipedes, worms, fireflies and glow worms on land, most of the world’s bioluminescence is in the ocean. The region about 660 feet to 3,300 feet deep in the ocean is known as the twilight zone.
Lots of bioluminescent animals live at this depth, including jellyfish, squid, shrimp, krill, marine worms and fish. In some parts of the ocean, these animals, not the sun, are the primary source of light.
Follow @timesonlinelk
comments powered by Disqus