Friday, May 21, 2010

Contaminating the dark

It is a sad irony that the journal Science arrives with a review article on bioluminescence in the ocean as billows of oil spew into the Gulf of Mexico.

Those dark, sunless depths where the goo gushes are full of delicate luminous beauty. The vast majority of bioluminescent organisms live in the oceans -- from bacteria to fish and everything in between. Diatoms, shrimp, jellyfish -- you name it, they glow with mysterious light, in every color of the spectrum.

Headlights for finding prey, or glowing lures to attract a meal.

Come-hither illuminations for attracting mates.

Light to deter predators, by signaling unpalatability, or by attracting secondary predators that will attack the first predator.

Even creatures where the sun don't shine have eyes, to see other creatures that decorate the dark with glowworm light.

At the top of the diagram (from Science, May 7, 2010) are four of the best known light-producing molecules, and below some of the organisms that use them. Nature has been endlessly inventive, contriving molecules that tease the senses. Light works particularly well below a kilometer deep in the sea were even bright sunshine is totally extinguished.

Which is where the sludge is presently issuing forth to blink out every light, one by one.