This video has Team Twilight Zone (TZ) member Marc Slattery explaining zonation. The community break was incredibly dramatic as you drift past an overhang at 190 ft to the undercut wall below. Large plating coral adapted to low light conditions (shallow-water species) extend to this transition, although their abundance decreases dramatically with depth. Below the rim of the overhand (below 200 feet) you see a greater diversity of sponges making the transition into a sponge dominated community. These sponges make their shallow-water relatives look very small as deep reef species that exceed 12 feet in diameter! Video courtesy of of the Twilight Zone Expedition Team 2007, NOAA-OE.