Deep-Sea Bioluminescence
Ventana’s regular voyages to the depths provide constant reminders that the great majority—perhaps 90 percent—of animals that inhabit the upper two kilometers (about 6,500 feet) or so of ocean waters are capable of producing light, and much of the detritus suspended in the water glows when it is disturbed.
MBARI
midwater scientists have observed a range of animals wielding light:
fragile shimmering comb jellies, medusae casting off glowing tentacles,
lanternfishes shining bioluminescent photophores, fang-toothed fish
dangling lures that harbor light-making bacteria, and many others. An
MBARI scientist published the first scientific paper to describe, from in
situ submersible observations, how the deep-sea animal Enypniastes
eximia, a swimming sea cucumber, produces and uses its light. Close
observations of the midwater squids Chiroteuthis (the swordfish
squid) and Galiteuthis (the cockatoo squid) have shown that they
use bioluminescence as camouflage.
Deep in the oxygen-minimum zone, MBARI researchers have discovered another manifestation of bioluminescence in a primitive relative of the octopus and the squid, Vampyroteuthis. Little was known of this elusive animal before it was filmed by Ventana’s cameras and live specimens were captured for studies at the institute’s chilled-seawater lab.
Just as MBARI’s extensive underwater surveys have demonstrated rich diversity in what was once thought to be a mostly lifeless realm, observations in the deep sea have also revealed surprisingly frequent illumination in a zone once thought to be devoid of light.