For most people, worms inspire images of garden pests or degradation tools for spoiled or discarded food. For University of California (UCSD) and Scripps Institution of Oceanography (SIO) researchers, worms are delicate, fluorescing buoyant creatures that swim in the deep sea above the sea floor. This frontier habitat for researchers at a depth of 3,280 to 13,120 feet is literally a new sea of research opportunity. “These [worms] are gorgeous with their transparent body, and their hundreds and hundreds of long, glass-like bristles that just glisten when you hit them with the lights of your camera,” said Karen Osborn, postdoctoral student and researcher in the lab of Prof. Greg Rouse at UCSD and SIO. “Recently, we discovered seven new species of swimming worms in the deep sea.” Five of these seven species have green bioluminescent appendages that are released from a worm in distress (nicknamed “green bombers”). These seven newly discovered species are described in the Aug. 21, 2009 issue of the journal Science. Osborn is given the primary credit for the discovery. Two of the seven species have gills in the same place where the green bombs exist on the bodies of the other five species. Aside from this difference, the seven worm species are very similar. Osborn and other evolutionary biologists use these similarities and differences as a model of the evolutionary process — a process that most likely began on the sea floor a million or so years ago. Based on her histology work with the worms, Osborn believes the bioluminescent, detachable appendages evolved from the traditional gills over time. As the worms moved their habitat up into the water column, the less-needed gills were replaced with the green bombs as a new sensory defense mechanism. After all, the water column presents more opportunities for a predator attack as compared with the sea floor with more hiding places and camouflage available. “[This is a]…great model to look at pelagic evolution,” Osborn stated. “One idea that I have is that once an animal moves into the water column, their food and mates are more diluted and it is harder to find these things. [Animals] need increased sensory ability to be able to seek these things out.” Up until recently, most sea life was only studied on the ocean floor. Aside from fish and other hard-bodied creatures, the animals in the upper water column are difficult, if not impossible to catch with a net. Gelatinous worms and other jelly-like creatures have eluded the analytical eyes of marine researchers for a long time. Now, with the help of modern technology, marine researchers are able to successfully collect animals from the water column and study them in captivity within their native marine habitat. Osborn and colleagues used remotely operated submersible structures only available at three institutions worldwide to collect and study their new specimens. On a typical dive, the scientists go out on a ship and sit in a control room with computer monitors. A pilot flies the submersible within the depth of the ocean that is requested by the scientists. There are usually several scientists giving directions to the pilot about where the submersible should go. “It is pretty chaotic sometimes!” Osborn said of the experience. Usually, the pilot flies the submersible for 12 hours while the scientists take turns running the underwater cameras. Then, they pull up the submersible and spend the evening analyzing and conducting experiments on their collected specimens. The next morning, they repeat the process again. Osborn stated that the newly discovered species of seven worms is usually pulled up in large numbers on these expeditions. Because of their large numbers, their existence has a significant impact on the ecology of the habitat. This collection process is so smooth that often the animals do not realize their capture. “With the submersible, the animals sometimes don’t even know they are being caught,” she said. “It’s a way to catch the animal in its surrounding water with its own environment.” She stated they had successfully captured a green bomber with all of its green bombs intact at the time of experimentation. There is so much work to be done in this region of the sea, and yet funding for exploratory work is harder and harder to win. Therefore, scientists do not pursue research on many of the species that they discover. “Every time we take the submersible down and work in the water column, we find new species,” Osborn said. “Generally, we ignore most of them — we don’t have the time to deal with them… there is a lot of work involved and very little scientific credit for doing that.” Their focus is generally on the most abundant species and those that have the most evolutionary significance. “[We] focus on evolutionary and ecologically important groups,” she said. This newly discovered group of seven worms fits both categories, evolutionary and ecologically significant. As more species are collected and analyzed, the chances of discovering new chemistries, new opportunities for medicinal therapy and new biological pathways increase. Oceanic food webs and climate change are better understood. Osborn and colleagues continue to reach toward these goals.