Before Deepwater Horizon, scientists didn't know that oil and marine snow had anything to do with each other. "Marine snow is like dust bunnies in the house," explained a research scientist who has studied the phenomenon for a long time. "All the gunk and little pieces in the ocean stick together, and underwater it looks like a snow-storm. The little particles aren't heavy enough to sink, but marine snow is big enough to sink very fast, 100 meters or more per day. It's the only way in which material that grows on the surface, where there is light, goes to depth....