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FATHOMING THE GULF STREAM - Nature's Pharmacy and Eyes In The Sea MISSION DISPATCH 5 • 08/23/02 Today's Weather - images courtesy of NOAA & RSMAS Dispatch by Brian Cousin - HARBOR BRANCH Oceanographic Institution Johnson-Sea-Link II launched this morning into a beautiful, calm sea, the yellow-and-black of the sub striking in the intense blue of the water. Dr. Shirley Pomponi and pilot Don Liberatore are on the way to the bottom to collect samples for the Biomedical Marine Research team, and to retrieve Dr. Tammy Frank's benthic traps. Last night's Tucker trawl rendered a few more animals than the previous trawl, but nothing ideally suited for electrophysiological testing. In the glass dish of captured organisms, a curious looking, transparent bubble with short tentacles bobs about in the shallow water. It's a three-inch long cranchiid squid and it's ingeniously well-adapted for existence in the clear, open ocean waters. The only non-transparent parts of its body, the eyes and gut, are specially designed to escape detection by potential predators. The eyes have bioluminescent organs located directly beneath them. By activating the light, and matching the downwelling light in intensity, the shape shadow created by each eye is eliminated. 
This unusual ability is known as counter-illumination.
The gut looks like a short piece of tinsel hanging in the squid's body: it's small, silver-colored
for reflectivity and oriented ventrally to dorsally,
rendering it all but invisible to predators lurking in the depths below it.
Dr. Sonke Johnson from Duke University, is looking at the colored animals in the collection, measuring color to determine how important camouflage might be to these inhabitants of the open ocean. "It's like an evolutionary arms race where they're trying to find other prey without being found themselves." This game of hide and seek in the ocean has created extraordinary adaptations. Dr. Johnson is studying the role an animals' color plays in the game of survival. "Can you color yourself to look like the background? Are you still the right color from another angle? Since we know what the underwater light field is like, we can predict what color an animal needs to be to blend in." Of the dark colored terrapods, the small brown swimming snails in the dish with the cranchiid squid, Sonke had this to say: "Maybe they're not too successful at camouflaging. Or maybe they're anti-camouflaged. Some animals use the color in their bodies to lure other animals in, or if they are 
poisonous, to keep other
animals away. Some jellies have colored tentacles that might look like a tempting little swarm of copepods
on an otherwise transparent body. They'll
draw another animal in and then attack. Either way, it's all a matter of advertising and hiding at the same
time. It's a nasty game and they're good at it."
The JSL has returned from the morning's dive, with sample buckets filled with sponges and gorgonians. Dr. Frank's traps are stowed in the collection basket. As she removes one of them, a crab's claw is seen protruding from the door. While this is not the optimal result, it does confirm that the new traps are able to catch the animals for which they were designed. Dr. Frank is not disheartened that this sample will likely not provide a measurable response. This is new science with deep-sea crabs, and methods and protocols need to be established for their correct handling. She places the crab in the shallow bath of the physiological prep and begins the process of experimentation. Shirley Pomponi spent the morning exploring more of the upper reaches of the tall pinnacle that John Reed dove on yesterday, collecting samples for drug discovery. During this afternoon's dive, she will return to the same site, but she'll explore the feature's intriguing flat top, collecting more samples and completing the characterization of flora and fauna for this mission. 
"We could easily spend all eleven days of the mission and more in this one area," says Reed.
In addition to the collecting data during the sub dives, Reed and Craig Russell, a Geographer with NOAA's Ocean Service Special Projects Office, are weaving the results of the ship's nightly transects into a 3-dimensional visualization of the site, right aboard ship, almost as the data is coming in. Russell is using a Geographic Information System (GIS) software package called 'ArcView' to plot over 150,000 points-representing latitude, longitude, and depth coordinates. These data were recorded by Reed using the ship's fathometer and sub-tracker. Russell says the number of points is too few to generate a detailed bathymetric plot useful for analysis, but the representation gives a good idea of the extent of the bottom relief. With a humbling mouse click, Russell changes the display to show the representation relative to the coastline. Suddenly the rugged bottom that consumed the entire screen shows up as a tiny pixel off the coast of South Carolina. On this leg of NOAA's mission of Ocean Exploration with HARBOR BRANCH's scientists, R/V Seward Johnson and the Johnson-Sea-Link II, a wealth of new knowledge has been gathered about this very special area on the Blake Plateau. There's still a long way to go. 
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