Scripps Institution of Oceanography, UC San Diego
The parchment tube worm glows green under a black light. Its natural blue glow is difficult to capture on camera.
One Fish, Two fish, Red Fish, Shoe fish
Trash on the bottom of the ocean used to be out of sight and out of mind, but a project by the Monterey Bay Aquarium Research Institute (MBARI) brought images of deep sea dumps to the surface. The MBARI team observed more than 1,500 pieces of trash on the seafloor from Vancouver Island to the Gulf of California, and as far west as the Hawaiian Islands.
Oceanic life sometimes made the best of this bad situation by colonizing the garbage. For example, this young rockfish is a shoe-in for survival and adaptation at 472 meters (1,548 feet) deep in San Gabriel Canyon, off Southern California.
Seafloor Social Network
Other young rockfish swim around discarded fishing equipment on the floor of Monterey Canyon off the coast of California. Luckily for them, the net isn't working. While some marine life may be able to adapt to human garbage, oceanic trash can trap animals, release toxins, smother plants and have other negative effects.
Boxing Day for Crabs
An octopus coils and crabs crawl over a metal box 2,432 meters (7979 feet) deep in Monterey Canyon.
This shipping container was discovered by MBARI four months after it fell off the merchant vessel Med Taipei during a storm in February of 2004. The container was just one of the estimated 10,000 shipping containers lost overboard every year.
Drums in the Deep
A wanna-be Sebastian the Crab, from Disney's the Little Mermaid, may be planning to turn this drum into a percussion instrument for a calypso band under the sea. The 55-gallon drum lies 2,892 meters (9,488 feet) deep in outer Monterey Canyon.
Even fragile garbage like this old cardboard can become part of the ocean floor ecosystem if it isn't handled with care. However, the crabs may be grouchy that cardboard covers their habitat 3,950 meters deep, offshore of Point Conception, Santa Barbara County, California.
A sea anemone (top) and sea cucumber (right) gained traction on the surface of this tire submerged 868 meters (2,850 feet) beneath the waves in Monterey Canyon.
The ubiquitous Coca Cola logo can be found even 1,200 meters deep in Monterey Canyon.
Classic Fish Pun
This old shoe is in pretty bad shape, but it seems to still have its sole...or is that a flounder (upper left)?
It's in the Water
The slogan of Olympia beer, “It's the water,” can barely be read on this old can. In this case, lots and lots of water.
Someone didn't turn in this soda bottle for a deposit. Instead, deep in the sea, brittle stars creep around the bottle on Davidson Seamount, 60 miles offshore of California and 1,727 meters (5,666 feet) below the ocean surface. "The most frustrating thing for me is that most of the material we saw—glass, metal, paper, plastic—could be recycled," said Kyra Schlining, lead author of the MBARI study published in Deep-Sea Research, in a press release.
The Long Black Veil
A gorgonian coral wears a veil of black plastic 2,115 meters (almost 7,000 feet) deep in Astoria Canyon, off the coast of Oregon. The veil could become a death shroud if the plastic were to completely cover the coral and block coral polyps from feeding.
Dr. Pepper's slogan could be modified to, “Would you like to be a polluter too?” for this can submerged 1,529 meters deep on Axial Seamount, off the Pacific Northwest's coast. The nearby brittle stars probably can't tell the difference between Dr. Pepper detritus and Mr. Pibb pollution.
One common sea worm has a rather uncommon trick: Chaeteopterus variopedatus -- also known as the parchment tube worm for the paperlike tubes it builds for itself and lives within throughout its life -- secretes a bioluminescent mucus that makes it glow blue.
Now, scientists are a step closer to understanding the mechanisms behind the worm's glow.
The parchment tube worm can be found on shallow, sandy seafloors all around the world. Its glow sets it apart from other tube worms, most of which don't glow, and other shallow water organisms, which typically emit green light, not blue.
Green light is more typical of shallow-water bioluminescence because it travels farther than any other color on the light spectrum, a useful quality in the turbid near-shore environment. [Gallery: Glowing Aquatic Life]
"Shallow water is much more complex than deep water from a physical standpoint, and green is what organisms see best," Dimitri Deheyn, a biologist at the Scripps Institution of Oceanography involved in the research, told LiveScience's OurAmazingPlanet. "If you produce light and you want light to be associated with an ecological function, you want organisms to see it."
Researchers have known about the unusual blue-glowing worm for decades, but nobody has ever looked closely at its light-emitting properties. Now, Deheyn and his colleagues have conducted two new studies that help characterize it.
First, the team found that, unlike light-emitting mechanisms in many other organisms, the worm does not require oxygen.
Light production usually occurs when two chemicals react together with oxygen to produce a compound that then produces light, Deheyn said. In past studies, researchers have found that glowing stops in the absence of oxygen.
But when Deheyn's team removed oxygen from the tube worm, the worm continued glowing. They reported these findings last month in the journal Physiological and Biochemical Zoology.
"In our case, if you remove oxygen, you don't stop the light," said Deheyn. "So the biochemical pathway that eventually leads to light production does not follow conventional characteristics."
In a separate experiment, the team found that riboflavin -- also known as vitamin B2 -- plays an important role in the worm's light production, but its exact role remains unclear. However, since the worms do not produce riboflavin on their own, they must be acquiring their glowing properties from their diet or from symbiosis with bacteria, the researchers recently reported in the journal Photochemistry and Photobiology.
The team still has not determined why the animals emit blue light or, even more broadly, why they produce light at all. They think it could be used to lure prey or to ward off predators, but this remains unclear, they say.
Still, these discoveries bring the researchers closer to understanding the array of different bioluminescent pathways in the animal world, of which researchers estimate there could be 20 to 30 varieties, only about three of which have been studied in detail, Deheyn said.
More From Livescience:
Gallery: Eye-Catching Bioluminescent Wonders
Bioluminescent: A Glow in the Dark Gallery
Extreme Life on Earth: 8 Bizarre Creatures
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