Mad for Mud

Jill Bourque (left) and Amanda Demopoulos, scientists at the U.S Geological Survey, extract sediments from a coring device pushed into the seafloor by the manipulator arms of the deep-sea sub Alvin. The sediments were sampled during a research cruise to test the upgraded sub in the Gulf of Mexico near a thriving community of deep-sea corals, anemones, and fish. Demopoulos and Bourque are studying invertebrates living in the sediments—worms, small crustaceans, and molluscs that perform a variety of functions in the ecosystem, serving as food for fish, for example, or helping to decompose carbon.  The animals are also sensitive to—and therefore indicators of—disturbances in the ecosystem, ranging from mudslides to pollution.(Photo by Lonny Lippsett, Woods Hole Oceanographic Institution)