A long-spined sea urchin (Diadema antillarum) at Texas Rock in the Dry Tortugas National Park. This image is part of documentation collected during the Greenpeace expedition to the Gulf of Mexico. Several teams of independent scientists join Greenpeace to conduct a series of scientific research programs. This work will further understanding of the impacts of both oil and chemical dispersants on the Gulf ecosystem in the aftermath of the BP Deepwater oil spill.