Brilliant color, delicate filigree, unusual patterns--there is much to like in this close-up view of a soft coral tree. Soft coral is a colony of very simple animals called polyps, which cluster together to form a tree-like structure; this photo is a close-up of the "trunk" of that tree. The polyps feed by filtering plankton from the sea, thus the colony responds to the amount of current going by them. In strong currents, the soft coral will open up and the trunk will be solid. In weak current, the polyps will close, and the trunk will shrivel up to a dark dull blob amid the ocean floor.