Karen Osborn of the Scripps Institution of Oceanography in San Diego, Calif. and colleagues have identified seven species of creatures who make bioluminescing "bombs" -- sea worms. These tiny worms wiggle through the darkness thousands of meters below the sea and when a predator attacks, the worms release a glowing green sac throwing off its chasers. The worms are relatives of earthworms and leeches and belong to the annelid phylum. They have been given the group designation Swima. Researchers have dubbed the newly discovered critters "green bombers."
Team member Steven Haddock of the Monterey Bay Aquarium Research Institute in Moss Landing, California, first saw one of these annelids flit across the camera viewfinder of a remotely operated submersible in 2001. Since then he, Osborn, and others have come across dozens more individuals. Most were spotted in canyons off the coasts of California and Oregon, but a few lived in the Philippines. They ranged in size from 18 to 93 millimeters and were between 1863 meters and 3793 meters below the surface, sometimes along the sea floor and other times in mid-ocean.
About two millimeters across, the glowing bombs are actually modified gills that consist of four chambers, likely holding apart fluids that react when they come into contact with each other to create light. Each worm has eight appendages for holding the sacs. When released, the sacs glow green for about a minute, Osborn reports. "It's a different chemistry than has been found in other polychaete worms in the same phylum," she says. She presumes the worms drop the bombs as a way of distracting predators.
Although some worms drop appendages during reproduction and others use bio-luminescence, "these two features were never found in combination [in annelids] until now," says Struck. The find drives home that even "simple" worms have sophisticated behavior, he says. And given that the researchers have found these creatures on both sides of the Pacific Ocean, Struck says, there are probably many more varieties out there, lighting up the sea as they go. Source: Science Now
The discovery has proven that we know so little about the ocean and the marine life. The research was funded by the Scripps Institution, University of California President's Postdoctoral Fellowship, David and Lucile Packard Foundation, National Oceanic and Atmospheric Administration, Woods Hole Oceanographic Institute and the National Geographic Society.
Karen Osborn of the Scripps Institution of Oceanography in San Diego, Calif. and colleagues have identified seven species of creatures who make bioluminescing "bombs" -- sea worms. These tiny worms wiggle through the darkness thousands of meters below the sea and when a predator attacks, the worms release a glowing green sac throwing off its chasers. The worms are relatives of earthworms and leeches and belong to the annelid phylum. They have been given the group designation Swima. Researchers have dubbed the newly discovered critters "green bombers."