Glass sponge reefs are a marvel of underwater architecture--made of living animals. The internal structure of a glass sponge is an intricate network of silica-based spicules, allowing these sponges to build up into the water column, where they filter feed bacteria out of deep sea currents. Our team explored regions of a 9,000 year-old glass sponge reef off the coast of Galiano Island, British Columbia, during exploration with our partners at Ocean Networks Canada. | Nautilus Live