1830-1882

Scottish naturalist and marine biologist who was one of the first to describe deep-sea life. On deep-sea dredging expeditions to the north of Scotland, Thomson discovered a diversity of marine invertebrates, many of which had been believed to be extinct. His finding that deep-sea temperatures are not as constant as had been thought indicated the presence of oceanic circulation. On another of his expeditions, the crew conducted observations of the three great ocean basins.